Method for producing a deoxidized fluid stream and apparatus for deoxidizing a fluid stream.

Abstract

The present invention relates to a method for producing a deoxidized fluid stream, comprising a direct-contact cooler and one or more heat pumps. The present invention further relates to an apparatus for deoxidizing a fluid stream, comprising a direct-contact cooler and one or more heat pumps.

Description

Technical Field

[0001] The present invention relates to a method for producing a deacidified fluid stream, comprising a combination of a heat pump for transferring energy from a heat source to a regeneration process and a direct contact cooler (DCC).

[0002] In a second aspect, the present invention relates to an apparatus for producing a deacidified fluid stream, comprising a heat pump and a direct contact cooler (DCC).

Background Art

[0003] In view of the pressing climate change and the increasing indicators of its dramatic impact on the world's population, the United Nations Sustainable Development Goals have identified the need to take "climate action" as one of the 17 Sustainable Development Goals. One of the 17 goals is to integrate climate action into national policies, strategies and plans. The European Union has imposed a series of climate change policy initiatives with the goal of making the European Union climate neutral by 2050. Due to more immediate effects, the greenhouse gas emission reduction target has been raised to about 50% compared to the 1990 level, aiming to achieve net-zero greenhouse gas emissions by 2050. Similar initiatives and incentives for climate protection measures are being taken by other governments around the world.

[0004] Carbon dioxide is one of the most abundant greenhouse gases in the atmosphere. Greenhouse gases are gases that absorb and emit infrared radiation in the wavelength range emitted by the Earth, thereby contributing to global warming. The CO2 level in the atmosphere has increased from about 280 ppm in the pre-industrial era around 1750 to about 421 ppm in 2022. Approximately two-thirds of all carbon dioxide emissions are due to the combustion of fossil fuels.

[0005] Most climate change countermeasures require massive financial investment and take years or even decades to implement.

[0006] Carbon capture and storage (CCS) or carbon capture utilization and storage (CCUS) are readily available and advanced technologies that can be implemented on a large scale and in shorter timescales, and therefore have a more direct impact on climate change. Carbon dioxide can be captured from industrial sources such as cement production, natural gas processing, and ammonia and hydrogen production, or directly from fossil or biomass fuel power plants. Currently, carbon capture rates of 80-95% from carbon-based fuel exhaust gases are realistic.

[0007] The captured carbon dioxide can be removed from the atmosphere by carbon sequestration or carbon storage in suitable geological structures such as depleted oil and gas reservoirs, mines and saltwater aquifers, or rock structures. Before transporting the carbon dioxide to its final storage site and injecting it underground, it is typically compressed to a high pressure of about 100 bar. Other uses for captured carbon dioxide include enhanced oil recovery or conversion into fuels, cement, minerals, or chemicals.

[0008] Currently, amine gas treatment is one of the most mature methods for carbon recovery. Amine gas treatment refers to the process in which acidic gases (sour gases) such as carbon dioxide or hydrogen sulfide are removed from a feed gas stream by absorption in an amine solvent. A typical acid gas removal unit (AGRU) includes an absorber, a regenerator, and auxiliary equipment. In the absorber, the amine flowing downward absorbs the acidic components of the feed gas, yielding a sweetened gas or a sweetened gas stream and a partially loaded amine solution ("rich amine"). The rich amine solution is then fed to a regenerator or stripper, where it is heated to strip or flush the desorbed acidic gas at the top of the column and produce a regenerated amine solution ("lean amine") that can be recycled back into the absorber. The stripped CO2 is then compressed and dried, optionally cooled, and transported to its storage destination.

[0009] Amine gas treatment is a relatively energy-intensive process. It is estimated that up to 40 percent of the energy produced by the power plant is consumed by carbon capture and sequestration. This energy penalty is divided between approximately 60% for the amine gas treatment process and 30% for carbon dioxide compression. The energy-intensive part of amine gas treatment is the stripping of captured carbon dioxide in the stripper. The temperature inside the absorber is typically around 30-70°C, while the temperature required to strip the carbon dioxide is typically in the range of 100-150°C. The energy required to heat the rich amine is usually supplied by transferring heat from high-temperature process vapor to the rich amine in the regenerator.

[0010] Process steam can be produced in combined cycle gas power plants. In such cases, steam production from power generation can be integrated into the amine gas treatment process. However, steam integration with existing steam sources is not always possible for all AGRUs; therefore, the required steam must be supplied by an independent process steam generation process, such as a steam boiler.

[0011] Therefore, in many activities, the need to reduce the energy consumption of amine gas processing units is being addressed.

[0012] One possible strategy to reduce energy consumption is to improve the circulation capacity of the amine solvent and attempt to reduce the energy required to regenerate the amine solvent. However, solvent development is very costly and time-intensive, often requiring the use of specialized, expensive solvent systems, which leads to higher operating costs.

[0013] Another strategy employed to reduce the energy consumption of amine gas processing units is to transfer heat from a source with a higher temperature to a lower temperature area within the gas processing unit.

[0014] The most prominent example of such heat transfer measures is the so-called cross-flow heat exchanger between the regenerator and the absorber, where the high-temperature lean amines exiting the regenerator heat the lower-temperature rich amines from the absorber before the rich amines are supplied to the regenerator. However, indirect heat exchange by the cross-flow heat exchanger is usually insufficient to supply the large amount of energy required to operate the stripper.

[0015] U.S. Patent No. 3,823,222 teaches that the energy contained in the high-temperature feed gas being deoxidized in the AGRU is used to produce steam in a separate boiler that can be used for steam stripping in the regenerator, thereby heating the reboiler of the regenerator.

[0016] U.S. Patent No. 3,101,996 also teaches that a high-temperature fluid flow, such as synthesis gas or hydrogen gas, obtained in a water shift reaction can be used to produce steam in a separate boiler that can be used to heat an amine stripper.

[0017] International Publication No. 200712143 discloses two separate cooling stages for cooling high-temperature exhaust gas from a steam turbine before amine gas treatment. In the first stage, the exhaust gas is cooled in a heat exchanger by indirect heat exchange with a fluid used to heat a stripper. In the second stage, the exhaust gas is cooled by transferring thermal energy to a heat pump system used to heat the stripper. The heat pump system can be supplemented with heat regenerated from other heat sources, such as a CO2 compression stage.

[0018] The use of heat pumps to transfer energy from process units with higher thermal energy levels to process units with lower thermal energy levels is not limited to high-temperature supply gases. It has been proposed to utilize almost all heat sources in amine gas processing processes in conjunction with heat pumps.

[0019] In International Publication No. 2010097047 and International Publication No. 2011122525, the heat pump utilizes the heat absorbed by the absorber as a heat source for heating the rich amine solution.

[0020] Japanese Patent Publication No. 2015-131735 describes a heat pump that uses an intercooler loop in an absorber as a heat source for heating a stripper.

[0021] International Publication No. 200781214 and Chinese Patent No. 114405258 disclose the use of condensation energy generated in a stripper condenser as a heat source.

[0022] International Publication No. 201258558 describes the use of the thermal energy of stripper gas in a top condenser as a heat source for a heat pump. While this disclosure is limited to the removal of SO2 from a gaseous mixture, the principle can theoretically be adapted for CO2 removal.

[0023] Japanese Patent Publication No. 2010-088982 discloses the use of the heat of compression generated in a compressor, which was used to compress carbon dioxide to high pressure, for heating a rich amine solution.

[0024] Japanese Patent Publication No. 2015-131736 essentially teaches the replacement of a conventional cross-flow heat exchanger, which is used to transfer heat from a high-temperature lean amine solution exiting a stripper to a rich amine solution entering a stripper, with a heat pump.

[0025] French Patent No. 2968574 discloses the use of multiple heat sources for a heat pump, including a top condenser for a stripper, a lean amine solution coming out of an absorber, and a top condenser for an absorber used to remove water vapor from a sweetening gas.

[0026] Similarly, Chinese Patent No. 10289584 refers to the use of lean amine solution and stripper tower top condenser as heat sources for a heat pump.

[0027] It is also possible to use an external heat source for the amine gas treatment process.

[0028] Chinese Patent No. 112126477 discloses the use of blast furnace slag rinse water as a heat source for heating a stripper by a heat pump.

[0029] The energy contained in the various heat sources disclosed is usually not high enough to provide the complete energy required for the stripping process. Therefore, multiple heat sources must be utilized, necessitating the use of more than one heat pump. The use of several heat pumps increases the capital cost of the amine gas treatment unit.

[0030] Despite numerous disclosures focusing on thermal integration in gas processing, there remains a need for thermal integration solutions that can supply most or all of the energy required for regenerators without resulting in a dramatic increase in capital costs. [Overview of the project] [Problems that the invention aims to solve]

[0031] Therefore, the fundamental problem underlying the present invention was to provide a method for reducing the energy demand of a gas treatment unit using a liquid absorbent while moderately limiting additional investment in plant infrastructure. A further fundamental problem underlying the present invention was to reduce corrosion and fouling of equipment in contact with the fluid flow. Another fundamental problem underlying the present invention was to avoid the need for expensive equipment required to transport the gas flow. In addition, an object of the present invention was to electrify the steam production required for the regeneration of the rich absorbent solution, potentially eliminating the need to separate steam production from power production within a power plant or to provide a separate steam production facility. A further object of the present invention was to reduce the energy demand for steam production required for the regeneration process. Yet another object of the further invention was to provide a gas treatment method that is flexible and can adapt to fluctuations in the load of the supply gas flow supplied to the gas treatment unit. This problem is becoming increasingly important as the introduction of energy from renewable resources into power grids, which are subject to fluctuations due to the availability of wind and solar power, increases. Such fluctuations in energy supply must be balanced by one of the carbon-fuel-based power plants that increase output to compensate for energy shortages, and therefore they themselves generate fluctuating exhaust gas flows, which need to be treated by an acid gas removal process. [Means for solving the problem]

[0032] First aspect - Method for producing a deoxidized fluid flow by a heat transfer process including two or more heat pumps In a first aspect, the present invention relates to a method for producing a deoxidized fluid stream, a) A heat energy transfer step to transfer thermal energy from a fluid flow FS1 containing at least one type of acidic gas to a regeneration step c) to obtain a fluid flow FS2 having reduced thermal energy compared to the fluid flow FS1, b) An absorption step in which a cooled fluid flow FS2 is brought into contact with absorbent A1 in an absorber to obtain absorbent A2 to which an acidic gas and at least partially deoxidized fluid flow are loaded, c) A regeneration step in which at least a portion of the loaded absorbent A2 obtained from step b) is regenerated in a regenerator to obtain at least partially regenerated absorbent A3 and a gas flow GS containing at least one acidic gas, d) A recycling process that recycles at least the by-flow of the recycled absorbent A3 from process c) back into the absorption process b), Includes, The thermal energy transfer process a) includes a combination of a direct contact cooler DCC and one or more heat pumps. method.

[0033] Heat energy transfer process a): The method of the present invention includes a) a heat energy transfer step of transferring thermal energy from a fluid flow FS1 containing at least one acidic gas to a regeneration step c) to obtain a fluid flow FS2 having reduced thermal energy compared to the fluid flow FS1.

[0034] fluid flow FS1 The fluid flow FS1 that transfers thermal energy to regeneration step c) can be any fluid flow containing at least one type of acidic gas.

[0035] Preferably, the fluid flow FS1 contains CO2. In addition to CO2, other acidic gases such as H2S, CS2, or COS may be present. In addition, sulfur oxide SO2 x and nitrogen oxides NO x It is possible that such a thing exists.

[0036] The acidic gas content in the fluid flow FS1 is generally 0.01% to 40% by volume, preferably 2% to 30% by volume, and more preferably 3% to 25% by volume.

[0037] The fluid flow FS1 introduced into the process of the present invention may contain water. The water content in the fluid flow is generally in the range from more than 0 volume% to the content corresponding to the saturation concentration of water in the fluid flow under existing pressure and temperature conditions.

[0038] The pressure of the fluid flow FS1 typically depends on the source of the fluid flow FS1, as will be further explained below.

[0039] Preferably, the fluid flow FS1 is exhaust gas.

[0040] The exhaust gas is preferably obtained by burning fossil fuels such as coal, natural gas, and petroleum, or carbon-based fuels such as biomass raw materials from plants, algae, or animals.

[0041] Such combustion processes can occur in power plants or power plants. Preferably, the source of the exhaust gas is the combustion of coal, natural gas, petroleum, biofuels such as bioethanol or biodiesel, or biomass obtained from forestry, agriculture or aquaculture.

[0042] Preferably, the fluid flow FS1 is exhaust gas from a steam turbine in a steam power plant where a generator is driven by steam obtained from the combustion of a carbon-based fuel.

[0043] Most preferably, the fluid flow FS1 is exhaust gas from a steam turbine of a gas-fired power plant designed as a simple-cycle gas turbine or a combined-cycle power plant.

[0044] Before being used in the method of the present invention, the exhaust gas flow FS1 is optionally treated to remove particulate matter by filtration or electrostatic deposition.

[0045] In a preferred embodiment, the exhaust gas flow FS1 is desulfurized by removing sulfur dioxide. For an overview of the exhaust gas desulfurization method, please refer to the Wikipedia article "Flue-gas desulfurization" (https: / / en.wikipedia.org / wiki / Flue-gas_desulfurization).

[0046] The fluid exhaust gas flow FS1 is preferably, CO2: 1-25% by volume, preferably 5-20% by volume. H2O: 3-50% by volume, preferably 5-30% by volume, O2: Contains 0.1 to 16% by volume, preferably 1 to 10% by volume.

[0047] Furthermore, even after the exhaust gas desulfurization process, the exhaust gas still contains small amounts of other gases, particularly nitrogen oxides (NOx) and sulfur oxides (SOx).

[0048] The exhaust gas also contains nitrogen in such quantities that the sum of the volume fractions of each component present in the exhaust gas equals 1 (or 100 vol%). Typically, the nitrogen content ranges from 40 to 95 vol%.

[0049] The fluid flow FS1 is preferably in a gaseous state. Depending on the temperature and water content, the fluid flow FS1 may also contain condensed water and acid.

[0050] When the fluid flow is exhaust gas, the pressure of the fluid flow FS1 entering the cooling process is usually atmospheric pressure, preferably in the range of 0.7 to 1.5 bar, more preferably 0.8 to 1.3 bar, and more preferably 0.9 to 1.2 bar.

[0051] The temperature of the fluid exhaust gas flow FS1 is preferably in the range of 50 to 300°C, preferably 60 to 250°C, and most preferably 60 to 200°C.

[0052] The fluid flow FS1 may also be an off-gas flow from which CO2 has been released in an industrial process that releases CO2 through a chemical reaction. Examples of such industrial process flows include CO2 emissions from the thermal decomposition of limestone and dolomite in cement production, CO2 emissions from the use of carbon as a reducing agent in the commercial production of metals from ore (e.g., iron production in blast furnaces), or CO2 emissions from the fermentation of biomass (e.g., to convert sugar into alcohol).

[0053] In a preferred embodiment, the fluid flow FS1 is a combined flow of exhaust gas from a carbon fuel combustion process and CO2 emissions from industrial processes that generate CO2, such as cement production, metal production, or fermentation processes.

[0054] In a further preferred embodiment, the fluid flow FS1 is an exhaust gas flow coming from a cracker furnace where petroleum fractions, naphtha, natural gas liquids, and hydrocarbons such as methane, ethane, and propane are thermally or catalytically cracked to obtain shorter-chain molecules or recombined molecules having different structures. Preferably, the fluid flow FS1 is the exhaust gas from a steam cracker furnace.

[0055] Alternatively, the fluid flow FS1 may be crude synthesis gas. Such synthesis gas (or "syngas") can be obtained from the gasification of coal or mineral oil, steam reforming of mineral oil distillates, steam reforming of methane, or autothermal reforming of natural gas. Syngas typically contains at least hydrogen, carbon monoxide, and some carbon dioxide and water.

[0056] The preferred fluid flow FS1 is the fluid flow exiting the aqueous shift reactor in synthesis gas production. The aqueous shift reaction is preferably carried out as a high-temperature shift conversion (HTSC) at a temperature of about 300-450°C, a medium-temperature shift conversion (MTSC) at a temperature of about 150-350°C, a low-temperature shift conversion (LTSC) at a temperature of about 150-250°C, or a sour gas shift conversion (SGS) at a temperature of about 200-300°C.

[0057] When the fluid flow is synthesis gas, the total pressure is typically in the range of 5 to 120 bar, preferably 10 to 100 bar, and more preferably 10 to 60 bar.

[0058] According to the present invention, the thermal energy transfer process includes a combination of a direct contact cooler DCC and a heat pump HP1.

[0059] Direct contact cooler (DCC) In step a), thermal energy from the fluid flow FS1 is transferred to regeneration step c) in a configuration that includes a direct contact cooler.

[0060] In direct-contact coolers, the term "direct contact" means that the flow FS1 and the flow functioning as a cooling medium or heat transfer material are not spatially separated by a partition, but are in direct physical contact with each other (direct heat exchange).

[0061] Direct heat exchange has the advantage of increasing the exchange area between the two fluids, reducing thermal resistance, and maximizing thermal efficiency. In addition, direct heat exchangers have a high heat transfer coefficient per unit volume, and fouling and corrosion are usually not a problem, so their operating and capital costs are typically lower than those of indirect heat exchangers. In indirect heat exchangers, if residual sulfur oxides (SOx) are present in the fluid flow FS1, corrosion is a significant problem, and corrosion can cause dew point corrosion if the temperature of any metal in contact with FS1 is below the dew point of sulfuric acid, which is typically in the range of 110-170°C. Furthermore, the pressure drop of direct contact coolers is lower compared to indirect gas-liquid heat exchangers. Therefore, it is possible to reduce the size of expensive equipment such as fans or blowers required to compensate for the pressure drop and transport the fluid flow FS2 to the absorber, or even avoid such equipment altogether.

[0062] Direct contact is preferably performed in a direct contact cooler (DCC), where heat is transferred from the fluid flow FS1 to the liquid cooling medium flow CMS1, resulting in a cooling medium flow CMS2 and a cooled fluid flow FS2 having higher thermal energy than the cooling medium flow CMS2. In this invention, the terms "direct contact condenser" and "direct contact cooler" are used as synonyms. This is because the degree of condensation that occurs in a DCC depends on the water content of the supply gas.

[0063] Direct contact cooling can be performed using the following devices: a) spray columns, b) baffled tray columns, c) sieve tray or bubble tray columns, d) packed columns, e) pipeline contactors, and f) mechanically agitated contactors.

[0064] For further details on the design of direct-contact condensers, please refer to the review article by Madejski et al. (Madejski, P.; Kus, T.; Michalak, P.; Karch, M.; Subramanian, N. Direct Contact Condensers: A Comprehensive Review of Experimental and Numerical Investigations on Direct-Contact Condensation. Energies 2022, 15, 9312. https: / / doi.org / 10.3390 / en15249312) and in Kreith, Frank & Boehm, Robert. (1987). Direct-Contact Heat Transfer. 10.1615 / AtoZ.d.DIRCONHEATRA, Chapter 19, pages 1359-1399.

[0065] Preferably, the direct-contact cooler operates in counterflow mode. This means that the heat flow FS1 typically enters the inlet opposite to the inlet of the cooling medium flow CMS1 or heat transfer material flow HTMS1. However, it is also possible to operate the direct-contact cooler in parallel flow mode, where the CMS1 or HTMS1 and FS1 enter the heat exchanger from the same direction. A parallel-flow direct-contact cooler is described in U.S. Patent No. 9034081.

[0066] The most preferred direct-contact coolers are spray columns, baffled tray columns, sieve trays or bubble tray columns, and packed columns. More preferably, the cooler operates in countercurrent mode.

[0067] In a direct-contact cooler, the heat flow FS1 preferably comes into direct contact with the cooling medium flow CMS1 or the heat transfer material flow HTM1, and thermal energy is transferred from the heat flow FS1 to obtain a cooled fluid flow FS2 and a heated cooling medium flow CMS2 or a heated heat transfer material flow HTMS2 or HTMS2a (see below).

[0068] Cooling medium streams CMS1 and CMS2 are flows of the cooling medium CM. The cooling medium CM is preferably one or more cooling media selected from the group consisting of ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol and their corresponding polyglycols, such as diethylene glycol, triethylene glycol, 1,2-dipropylene glycol, 1,2-tripropylene glycol, 1,3-dipropylene glycol, and 1,3-tripropylene glycol, their corresponding methyl or dimethyl ether, and water. Preferably, the cooling medium CM is ethylene glycol or water, or a mixture of ethylene glycol and water. Most preferably, the cooling medium CM consists essentially of water. The use of pure water has the advantage of not requiring an additional separation step. An additional separation step is preferable when the cooling medium stream CMS1 contains components other than water. This is because the water contained in the heat stream FS1 results in a dilution of the concentration of other non-aqueous components. To restore the original concentration, an additional separation step is preferred to separate the water introduced into the cooling medium flow CMS1 or CMS2 together with the heat flow FS1.

[0069] Direct-contact coolers are preferably designed in a manner that satisfies the following requirements: - Temperature T CMS1 The temperature range is 25 to 100°C, preferably 25 to 70°C, and more preferably 30 to 50°C. - Temperature T CMS2 is, T CMS1 It is approximately 5-100K higher than, preferably 10-80K, and more preferably 15-50K higher. - Temperature T FS2 The temperature is preferably in the range of 20 to 80°C, more preferably 25 to 70°C, and most preferably in the range of 30 to 60°C.

[0070] Direct contact coolers are also typically operated so that the cooling medium flow CMS2 remains in a liquid state, and thus the cooling medium flow CMS2 can be easily separated from the gaseous fluid flow FS2.

[0071] A portion of the cooling medium flow CMS2 can be purged from the cooling medium flow cycle if it contains additional moisture in the fluid flow FS1. The amount of cooling medium flow to be purged is selected so that the cooling medium flow rate remains essentially constant.

[0072] In a preferred embodiment, the direct-contact cooler is designed to deliver more energy than is required to supply to the regeneration process. In this case, the excess energy may preferably be used to supply excess steam, which can then be transferred to the on-site steam network and distributed to other processes or process steps where such energy may be needed.

[0073] Alternatively, it is possible to design a direct-contact cooler so that less energy is transferred than is required for the regeneration process. In this case, it is preferable to supply additional energy, preferably steam, to the regeneration process from another source, such as a site steam network that distributes steam from another steam production source.

[0074] The direct-contact cooler is preferably designed so that the thermal energy transferred is just enough to supply the thermal energy required in regeneration step c). If the heat flow FS1 contains more thermal energy or heat than needs to be transported to regeneration step c) by the heat pump, then only the energy required in regeneration step c) is transferred by the direct-contact cooler. If, after transferring the heat or thermal energy required for regeneration step c), the fluid flow FS2 becomes too hot to enter the absorber, it is preferable that the fluid flow FS2 be cooled by one or more additional heat exchangers so that the fluid flow FS2 has a temperature in the range of 20-80°C, more preferably 25-70°C, and most preferably 30-60°C at the inlet of the absorber before it enters the absorber. Such additional heat exchangers are air coolers or water coolers such as cooling towers. For an overview of cooling towers that may be used to further cool the fluid flow FS2, see the Wikipedia article "Cooling towers" (https: / / en.wikipedia.org / wiki / Cooling_tower#). This embodiment has the advantage that the temperature of the fluid flow FS2 at the absorber inlet can be adjusted independently of the operation of the heat pump HP1, as described below.

[0075] heat pump According to the present invention, the transfer of thermal energy from the heat flow FS1 to the regeneration process c)) also includes one or more heat pumps.

[0076] Within the scope of the present invention, a heat pump is a device for transferring heat from a heat source at a certain temperature to a heat sink at a higher temperature.

[0077] The heat pump may be a conventional heat pump used in the process according to Embodiment A described below, or two or more conventional heat pumps connected in series and capable of operating according to Embodiment B described below. The heat pump may also be a so-called modified heat pump that operates according to the process described below in Embodiment C. The so-called modified heat pump differs from a conventional heat pump in that the evaporator of the heat pump is replaced with a heat exchanger in which the working fluid does not undergo a phase transition, followed by a separate evaporation means for evaporating the heat transfer material. In other words, the heat transfer and evaporation that are affected in the evaporator of a conventional heat pump are carried out in two separate process steps as described below in Embodiment C.

[0078] Conventional heat pumps Conventional heat pumps, - A heat exchanger HE1 transfers thermal energy from the cooling medium flow CMS2 to the heat transfer medium flow HTMS1 of the heat pump HP1, and obtains a heat transfer material flow HTMS2 having increased thermal energy compared to the heat transfer medium flow HTMS1. - One or more compressors for compressing a heat transfer material flow HTMS2 in one or more compression steps to obtain a heat transfer material flow HTMS3 having increased pressure compared to the heat transfer material flow HTMS2, - A heat exchanger HE-R for transferring thermal energy from the heat transfer material flow HTMS3 to the regeneration process, - Heat transfer material HTM1, Includes.

[0079] A heat transfer process a) including a combination of a direct contact cooler and a conventional heat pump is further described in Embodiment A below.

[0080] Series-connected heat pumps A series-connected heat pump means that the compressed heat transfer medium of heat pump HP1 acts as the heat source for the heat transfer medium flow of heat pump HP2, which acts as the heat sink for heat pump HP1, and the thermal energy from the heat transfer medium flow HTMS of heat pump HP1 to the heat transfer medium flow of heat pump HP2 is affected via a common heat exchanger HE2. In other words, the heat exchanger HE2 acts as the condenser for the heat transfer material HTM1 of heat pump HP1 and the evaporator for the heat transfer material HTM2 of heat pump HP2. Therefore, a series-connected heat pump is, - A heat exchanger HE1 transfers thermal energy from the cooling medium flow CMS2 to the heat transfer medium flow HTMS1 of the heat pump HP1, and obtains a heat transfer material flow HTMS2 having increased thermal energy compared to the heat transfer medium flow HTMS1. - One or more compressors for compressing a heat transfer material flow HTMS2 in one or more compression steps to obtain a heat transfer material flow HTMS3 having increased pressure compared to the heat transfer material flow HTMS2, - A heat exchanger HE2 for transferring thermal energy from the heat transfer medium flow HTMS3 to the second heat transfer medium flow SHTMS1 of the heat pump HP2, and obtaining a second heat transfer medium flow SHTMS2 having increased thermal energy compared to the heat transfer medium flow SHTMS1, - One or more compressors for compressing a second heat transfer material flow SHTMS2 in one or more compression steps to obtain a heat transfer material flow SHTMS3 having increased pressure compared to the heat transfer material flow SHTMS2, - A heat exchanger HE-R for transferring thermal energy from the heat transfer material flow HTMS3 of the first heat pump HP1 to the regeneration process, - Heat transfer material HTM1 and heat transfer material HTM2 Includes.

[0081] The use of two heat pumps connected in series has the advantage that the thermal energy from the heat flow HS1 can be increased to a level in heat pump HP2 that is capable of effectively generating steam, which can then be used to transfer heat to the regeneration process c). Thus, the flow generated in heat pump HP2 can effectively replace the process steam that is normally required as a heat source in the regeneration process c). Therefore, the use of two heat pumps connected in series can replace the need to install a separate process steam production process at the location of the acid gas removal unit, or the need for a steam turbine such as a back pressure turbine or extraction condensate turbine, and can generate process steam in a power plant that is to be decarbonized. Thus, the present invention is particularly useful when process steam is not readily available at the location of the acid gas removal unit. However, in locations where steam is readily available, the method according to the present invention may also be useful as an alternative method for generating process steam, as it allows potentially limited process steam resources to be used for other purposes, or as it allows for a reduction in power plant power losses associated with process steam production. In addition, the method of the present invention is an interesting alternative in the design of a new power plant coupled with an acid gas removal unit for carbon capture. This is because it reduces the need to divert energy used for steam production to power the recycling process. In addition, the method of the present invention is a useful method for electrifying steam production so that the steam required for the amine gas treatment process can be supplied by "green" electricity from renewable resources.

[0082] A heat transfer process a) including a combination of a direct-contact cooler and a heat pump connected in series is further described in Embodiment B below.

[0083] Modified heat pump The heat pump of the present invention can also be designed as a modified heat pump.

[0084] In the modified heat pump, the heat exchanger HE1 is a heat exchanger, not an evaporator, and is configured so that a phase transition from a liquid heat transfer material flow HTMS1 to a gaseous heat transfer material flow HTMS2 does not substantially occur, but rather a liquid heat transfer material flow HTMS2a is obtained, and the phase transition from the liquid heat transfer material flow HTMS2a to obtain a gaseous heat transfer material flow HTMS2b proceeds by supplying the heat transfer material flow HTMS2a to the evaporation means. The evaporation means is usually a combination of an expansion valve and an expansion vessel. Expansion is preferably p HTMS2a This is carried out as flash evaporation of the heat transfer material flow HTMS2a via an expansion valve or throttle valve into a vessel having a lower pressure. Thus, in the modified heat pump, the heat transfer process and the evaporation process are carried out as separate process steps. Therefore, the modified heat pump includes a heat exchanger HE1 and further means for the expansion or evaporation of the liquid heat transfer material flow HTMS2a.

[0085] The use of a modified heat pump in which the heat transfer process and the evaporation process are two distinct processes also has the advantage that the thermal energy from the heat flow HS1, particularly FS1, can be increased to a level in the heat pump HP1 that is capable of generating steam, which can then be used to transfer heat to the regeneration process c). This embodiment has similar advantages to a series-connected heat pump.

[0086] A heat transfer process a) including a combination of a direct contact cooler and a modified heat pump is further described in Embodiment C below.

[0087] Heat transfer material Heat pumps typically contain heat transfer materials.

[0088] The heat transfer material HTM1 is the working fluid used in the HP1 heat pump.

[0089] The heat transfer material HTM2 is the working fluid used in the second serial heat pump HP2.

[0090] If more than two heat pumps are connected, additional heat transfer materials HTM3 to HTMx may be used in heat pumps HP3 to HPx.

[0091] The heat transfer material HTM1 is a working fluid used in the heat pump HP1 to transport thermal energy from heat exchanger HE1 to heat exchanger HE2 or heat exchanger HE-R, depending on the embodiment and design of the heat pump HP1.

[0092] Preferably, the heat transfer material HTM1 can undergo at least a partial phase transition from liquid to gaseous state during the transfer of thermal energy in the heat exchanger HE1 (in the case of a conventional heat pump) and during the subsequent expansion step (in the case of a modified heat pump).

[0093] Preferably, the heat transfer material HTM1 may also undergo at least a partial phase transition from a gaseous to a liquid state when transferring thermal energy in the heat exchanger HE2 (in the case of a series-connected heat pump) or the heat exchanger HE-R (in the case of a single conventional heat pump or a single modified heat pump).

[0094] Therefore, the heat transfer substance HTM1 is preferably selected from the group of refrigerants consisting of ammonia, butane, R1233zd(e), R1224yd(z), air, CO2, water, chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, hydrofluoroolefins, hydrochlorofluoroolefins, hydrocarbons, perfluoro(2-methyl-3-pentanone), and mixtures of two or more thereof. Suitable refrigerants are well known to those skilled in the art and are disclosed, for example, in C. Arpagaus et al. (Energy 152 (2018), pages 985 to 1010).

[0095] In the case of a single conventional heat pump or a single modified heat pump, the heat transfer material HTM1 is most preferably water. When the heat transfer material HTM1 is water, it can be used directly, particularly in the reboiler HE-R or other plants at the integrated site, for the steam production required in the regeneration process c). In addition, water is an environmentally friendly heat transfer material that can be released into the environment either directly or after being fed into a wastewater treatment plant. Water is also readily available in many plants or facilities and can provide the required amount without the need for water reuse. Water has the further advantage that if the regeneration process requires more steam than is produced using the heat pump, steam can be supplemented from other sources in some cases, or if an excess amount of steam is produced, the steam can be distributed to other consumers, such as the on-site steam network. This makes the process of the present invention very flexible.

[0096] Similarly, the second heat transfer material HTM2 of heat pump HP in two series-connected heat pumps HP1 and HP2 is also most preferably water. This choice of water as the preferred heat transfer material generally applies to the last heat pump in a series of connected heat pumps.

[0097] In the case of two heat pumps connected in series, the HTM1 of heat pump HP1 is typically a heat transfer material having a lower boiling point than water in the condenser state of heat pump HP, most preferably ammonia, butane, R1233zd(e), R1224yd(z), air, CO2, water, chlorofluorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, hydrofluoroolefin, hydrochlorofluoroolefin, hydrocarbon, perfluoro(2-methyl-3-pentanone), and mixtures of two or more thereof. Using a heat transfer material HTM1 with a lower boiling point in the first heat pump HP1 allows for a higher flow of heat from the fluid flow FS1, especially when the temperature of the fluid flow FS1 or the cooling material CMS2 is not high enough to directly generate steam. In the case of two heat pumps connected in series, the heat transfer material HTM1 of heat pump HP1 is preferably ammonia or butane, most preferably ammonia.

[0098] Open-loop heat pumps and closed-loop heat pumps The conventional or series-connected heat pumps described above may be designed as open-loop or closed-loop heat pumps.

[0099] Open-loop heat pumps are typically, - Typically designed as an evaporator for at least a portion of the heat transfer material in a heat pump, the process involves transferring thermal energy from a heat source to a heat transfer material, usually by a heat exchanger. - A process of compressing a partially gasified heat transfer material in one or more compression steps, usually including one or more compressors, to raise the temperature of the heat transfer material, - Typically, the process involves transferring thermal energy from the compressed heat transfer material to the heat sink by another heat exchanger that functions at least partially as a condenser for the gaseous heat transfer material in the heat pump, Includes.

[0100] Open-loop heat pumps have the advantage of being able to utilize media from various sources, particularly water that is usually already present in the amine gas treatment process.

[0101] A closed-loop heat pump typically contains a heat transfer medium within a closed loop between the heat source and the heat sink. This is usually achieved by an additional recycling process for the heat transfer medium, such as a recycling process R1 or R2 for the heat pump HP1 or HP2, as will be further described below.

[0102] The modified heat pump described above is preferably designed as an open-loop heat pump. Open-loop heat pumps have the advantage of being able to utilize media from various sources, particularly water that is usually already present in the amine gas treatment process. In addition, open-loop heat pumps do not require the recycling of heat transfer materials, which simplifies the heat pump design and potentially makes them more cost-effective.

[0103] Embodiment configured for thermal integration including a direct contact cooler and a heat pump in energy transfer process a): The combination of a direct-contact cooler and a heat pump enables an efficient and flexible method for utilizing the fluid flow FS1 as a heat source to provide heat for the acid gas removal and regeneration process c).

[0104] Fluid flow FS1 often has low temperatures that make it unsuitable for direct steam generation. Furthermore, fluid flow FS1 can induce corrosion in downstream equipment.

[0105] Large fluid flows, such as FS1, are often difficult to handle and transport, resulting in a significant pressure drop in the equipment, which needs to be overcome by additional pumps or fans to transport the large volume of gas flow.

[0106] The use of a direct contact cooler has the advantage of mitigating the aforementioned drawbacks, making it feasible to use fluid vapor FS1 as a heat source.

[0107] Direct-contact coolers have the advantage of a large exchange area between the fluid flow FS1 and the cooling medium flow CMS1, reducing thermal resistance and maximizing thermal efficiency. In addition, direct-contact coolers have a high heat transfer coefficient per unit volume, and fouling and corrosion are usually not a problem, resulting in lower operating and capital costs than indirect heat exchangers. In indirect heat exchangers, if residual sulfur oxides (SOx) are present in the fluid flow FS1, corrosion is a significant problem, and corrosion can cause dew point corrosion if the temperature of any metal in contact with FS1 is below the dew point of sulfuric acid, which is typically in the range of 110-170°C. Furthermore, the pressure drop of direct-contact coolers is lower compared to indirect gas-liquid heat exchangers. Therefore, it is possible to reduce the size of expensive equipment such as fans or blowers required to compensate for the pressure drop and transport the fluid flow FS2 to the absorber, or even avoid such equipment altogether.

[0108] By using a heat pump in combination with a direct contact cooler, it becomes possible to use electricity to bring the heat contained in the fluid flow FS1 to the level required for the regeneration process. In particular, if the heat transfer material such as HTM1 or HTM2 of the (final) heat pump is water, the steam required for regeneration process c) can be produced directly with a relatively low energy input.

[0109] Thermal integration, including DCC and a heat pump, enables the transfer of thermal energy from a fluid flow FS1 having a relatively low temperature. Furthermore, the thermal integration of the present invention results in a process in which corrosion is significantly reduced. Thus, the method of the present invention enables improved thermal integration in acid gas treatment. Operational and capital expenditures for operating and constructing the process according to the present invention are favorable, and the method of the present invention is highly flexible and can compensate for load fluctuations of the fluid flow FS1.

[0110] The integration of the direct contact cooler and the heat pump of the present invention can be demonstrated by one of the embodiments A, B, and C described later in the heat transfer step a).

[0111] Embodiment A demonstrates the integration of a direct-contact cooler with a conventional heat pump.

[0112] Embodiment B demonstrates the integration of a direct-contact cooler with two series-connected heat pumps.

[0113] Embodiment C demonstrates the integration of a direct-contact cooler with a so-called modified heat pump.

[0114] The embodiments of the present invention are not intended to be exhaustive and should not be construed as being limited to the embodiments disclosed. Rather, the embodiments are selected and described to illustrate the principles and practices of the present invention.

[0115] Embodiment A: Conventional heat pump The transfer of thermal energy from the fluid flow FS1 to the regeneration process c) of process a) preferably includes a combination of a direct contact cooler and a so-called conventional heat pump.

[0116] The transmission step a) of Embodiment A is, (i) A step of transferring thermal energy from the fluid flow FS1 to the cooling material flow CMS1 in a direct contact type cooler, and obtaining a fluid flow FS2 having reduced thermal energy compared to the cooling material flow CMS2 and the fluid flow FS1, (ii) A step of transferring thermal energy from the cooling material flow CMS2 to the heat transfer material flow HTMS1 in the heat exchanger HE1, and obtaining a heat transfer material flow HTMS2 having higher thermal energy than the heat transfer material flow HTMS1, (iii) A step of compressing the heat transfer material flow HTMS2 in one or more compression steps to obtain a gaseous heat transfer material flow HTMS3 having a higher pressure than the heat transfer material flow HTMS2, (iv) A step of transferring thermal energy from the heat transfer material flow HTMS3 to the regeneration step c) to obtain the heat transfer material flow HTMS4, It is preferable to include it.

[0117] Figure 1 shows the process configuration according to Embodiment A.

[0118] Step i) In step i) of Embodiment A, the thermal energy from the fluid stream FS1 is transferred to the coolant stream CMS1 in the direct contact cooler to obtain a coolant stream CMS2 and a cooled fluid stream FS2.

[0119] The principle and design of the direct contact cooler in step i) are described in the above appropriate paragraph "Direct Contact Cooler".

[0120] Step ii) In step ii) of Embodiment A, the thermal energy from the coolant stream CMS2 is preferably transferred to the heat transfer medium stream HTMS1 in the heat exchanger HE1 to obtain a gaseous heat transfer medium stream HTMS2 having a higher thermal energy than the heat transfer medium stream HTMS1 and a coolant medium stream CMS3 having a lower thermal energy than the coolant stream CMS2.

[0121] The heat exchanger HE1 preferably - an inlet for the coolant stream CMS2 having a pressure p CMS2 and a temperature T CMS2 at the inlet end of the inlet, and - an outlet for the coolant stream CMS3 having a pressure p CMS3 and a temperature T CMS3 at the outlet end of the outlet, and - an inlet for the heat transfer medium stream HTMS1 having a pressure p HTMS1 and a temperature T HTMS1 at the inlet end of the inlet, and - an outlet for the coolant stream HTMS2 having a pressure p HTMS2 and a temperature T HTMS2 at the outlet end of the outlet, and includes.

[0122] The heat exchanger HE1 is preferably an indirect heat exchanger such as an evaporator, and in particular, HE1 is preferably a tube-type heat exchanger, preferably a shell-tube type heat exchanger, a double-tube heat exchanger, a drip-type heat exchanger, or a plate-type heat exchanger. Most preferably, the heat exchanger HE1 is a shell-tube type heat exchanger or a plate-type heat exchanger.

[0123] In the case of indirect heat transfer via an intercooling cycle, the heat exchanger HE1 is preferably designed to satisfy the following requirements: - Temperature T CMS2 The temperature range is 25 to 120°C, preferably 30 to 100°C, and more preferably 40 to 70°C. - Temperature T HTMS2 is, T HTMS1 It is approximately 0.1 to 50K higher, preferably 0.5 to 25K, and more preferably 1 to 10K higher than the given temperature. - The heat transfer material HTM1 in the heat transfer material flow HTMS1 undergoes at least a partial phase transition from liquid to gaseous state.

[0124] Step ii) of Embodiment A preferably yields substantially a gaseous heat transfer material flow HTMS2 and a cooled cooling medium flow CMS3, the cooled cooling medium flow CMS3 being recycled back to step i) as cooling medium flow CMS1. To impart the properties of cooling medium flow CMS1 to cooling medium flow CMS3, an additional cooling step may be performed by the cooling medium CMS3 in a heat exchanger HE-CMS, which is preferably a cooler, more preferably an air or water cooler. Preferably, cooling medium flow CMS3 is cooled to the temperature at which cooling medium flow CMS1 is introduced into a direct contact cooler HE-C.

[0125] Process iii) After thermal energy is transferred to the heat transfer medium flow HTMS2, the thermal energy is further transferred, preferably in step iii) of Embodiment A, by compressing the heat transfer medium flow HTMS2 in the heat pump HP1 to obtain a heat transfer medium flow HTMS3 having a higher pressure than the heat transfer medium flow HTMS2.

[0126] It is preferable that the compression is affected in the compressor.

[0127] A compressor is a device for increasing the pressure of a gaseous fluid, at least partially.

[0128] Compressors are typically positive displacement compressors or power compressors. Positive displacement compressors include reciprocating compressors that use a piston driven by a crankshaft to deliver fluid at higher pressure. Reciprocating compressors can be single-stage or multi-stage. Positive displacement compressors also include rotary screw compressors, conical screw compressors, rotary vane compressors, rolling piston compressors, or scroll compressors.

[0129] The compressor may also be a powered compressor, such as a centrifugal compressor or an axial flow compressor.

[0130] Preferably, the compressor is a rotary screw compressor, a centrifugal compressor, a piston compressor, or an axial flow compressor.

[0131] Compression can be carried out by one compressor or a series of compressors, depending on the desired pressure increase of the heat transfer material HTM1.

[0132] The heat transfer material HTM1 flows through the heat transfer material flow HTMS2 at pressure p HTMS2 and temperature T HTSM2 Then the compression process begins, and the heat transfer material HTMS3 is subjected to pressure p HTMS3 and temperature T HTMS3 Then it exits the compression process.

[0133] Pressure rise Δp(p HTMS3 -p HTMS2 Typically, the temperature of the heat transfer medium flow HTMS3 is selected to rise to the temperature required in regeneration step c), as described below.

[0134] In a preferred embodiment, the compression process is carried out in a series of two or more compressors, and the heat transfer material HTM1 is water. In this embodiment, an additional flow of heat transfer material HTM1 is supplied after each of the series compressors, increasing the amount of gaseous heat transfer material HTM1 produced at the expense of lowering the flow temperature. In this way, sufficient steam generation for the regeneration process c) can be achieved. In addition, the addition of further heat transfer material HTM1 is energetically preferable compared to a scenario in which the same amount of gaseous heat transfer material HTM1 is produced without the additional heat transfer material HTM1 being introduced after the compression process. Preferably, saturated steam is produced and used for heating the reboiler HE-R. Injecting water between the compressor compartments helps to reduce steam superheating. In addition, the injection of additional heat transfer material HTM1 results in a reduction in volumetric flow rate and a reduction in the power required of subsequent compressors in the continuous compression stage.

[0135] Step iii) of Embodiment A results in a compressed heat transfer material flow HTMS3.

[0136] Process iv) In Embodiment A, in step iv), thermal energy is transferred from the heat transfer medium flow HTMS3 to the regeneration step c), thereby obtaining a heat transfer medium flow HTMS4 having a reduced thermal energy content compared to HTMS3.

[0137] The transfer of thermal energy from the heat transfer material flow HTMS3 to the regeneration process c) may occur indirectly or directly, as described below.

[0138] Indirect heat transfer to regeneration process c) In a preferred variant of step iv), the transfer of thermal energy from the heat transfer material flow HTMS3 to the regeneration step c) takes place in the heat exchanger HE-R, where the loaded absorbent A2 obtained in step b) is heated before entering the regeneration step c).

[0139] The heat exchanger HE-R may be replaced with a cross-flow heat exchanger used to transfer heat from the regenerated absorbent A3 to the loaded absorbent A2 before entering the regeneration process c), or an additional cross-flow heat exchanger may be added to it.

[0140] The heat exchanger HE-R is preferably an indirect heat exchanger.

[0141] If the heat exchanger HE-R is an indirect heat exchanger, HE-R is preferably, - The inlet for the loaded absorbent A2, - At the inlet of the heat exchanger HE-R, the outlet of the loaded absorbent A2 has increased thermal energy compared to the loaded absorbent A2, - Pressure p at the inlet end of the inlet SHTMS1 and temperature T SHTMS1 The inlet of the second heat transfer medium flow HTMS1 having, - Pressure p at the outlet end of the outlet SHTMS2 and temperature T SHTMS2 The outlet of the second heat transfer medium flow HTMS2 having, Includes.

[0142] More preferably, the heat exchanger HE-R is a shell-and-tube type exchanger or a plate type exchanger.

[0143] This embodiment may be particularly useful when the fluid flow FS1 is exhaust gas and when an intermediate evaporation or flushing process is performed after the cross-flow heat exchanger HE-CF (see below). In this case, at least the partially loaded absorbent flow A2 can be reheated before entering the regenerator.

[0144] Direct heat transfer to regeneration process c) In the most preferred embodiment of step iv), thermal energy is directly transferred in the heat exchanger HE-R from the heat transfer medium flow HTMS3 to the absorbent flow AS1 drawn from the regenerator in step c), thereby obtaining an absorbent flow AS2 having increased thermal energy compared to the absorbent flow AS1, and supplying AS2 to the regenerator in step c).

[0145] More preferably, the transfer of thermal energy is influenced through a heat exchanger HE-R connected to the bottom of the regenerator, and the heat exchange proceeds indirectly. Most preferably, the indirect heat exchanger HE-R is a reboiler.

[0146] The reboiler typically includes an inlet connected to the bottom of the regenerator, through which the absorbent flow AS1 enters the reboiler, and an outlet connected to an inlet at the bottom of the regenerator, through which the absorbent flow AS2 exits the reboiler and re-enters the regenerator.

[0147] The reboiler also includes an inlet through which a second heat transfer material flow HTMS3 enters and an outlet through which a second heat transfer material flow HTMS4 exits the reboiler.

[0148] The HE-R is preferably a reboiler selected from the group consisting of a kettle-type reboiler, a thermosiphon reboiler, and a forced-circulation reboiler.

[0149] Heating of the absorbent flow AS2 typically causes acidic gases, particularly CO2, to be desorbed, and the water contained in the absorbent evaporates at least partially to form a flow, promoting a stripping effect that leads to further release of acidic gases from the loaded absorbent.

[0150] Further details regarding the regeneration process c) and the recycling process d) are specified in later paragraphs of this specification.

[0151] recycling In a preferred embodiment, Embodiment A includes an additional recycling step R1) to expand the heat transfer material flow HTMS4 obtained in step iv) to obtain a heat transfer medium flow HTMS5 having a reduced pressure compared to the heat transfer material flow HTMS4 and being at least partially recycled back to step i) as a heat transfer material flow HTMS1.

[0152] Expansion is preferably caused by the pressure p of the heat transfer medium flow HTMS4. HTMS4 The pressure p of the heat transfer medium flow HTMS5 HTMS5It is affected in order to lower it.

[0153] Expansion is preferably influenced by a thermal expansion valve. Thermal expansion valves that can be used in the recycling process R1) are described in the Wikipedia article "Thermal Expansion Valve," https: / / en.wikipedia.org / wiki / Thermal_expansion_valve. HTMS4 from p HTMS5 A pressure reduction Δp typically results in adiabatic flash evaporation of a portion of the heat transfer medium flow HTMS4, and the self-cooling effect of this adiabatic flash evaporation causes the temperature of the heat transfer medium flow HTMS4 to decrease.

[0154] The expansion valve is configured such that the heat transfer material flow HTMS5 can preferably be recycled to step 1 as the heat transfer material flow HTMS1, HTMS5 ga p HTMS1 Equivalent to, T HTMS5 is T HTMS1 It is preferable that it be operated and designed to be equal to [a certain value].

[0155] The execution of an additional recycling process R1) has the advantage of allowing the heat transfer material HTM1 to be reused in a closed-cycle heat pump in order to save material costs and resources, or to prevent environmental pollution associated with the loss of the heat transfer material HTM1 when an environmentally harmful heat transfer material HTM1 is selected.

[0156] If the heat transfer material HTM1 is water / steam, it is not essential to expand the heat transfer material flow HHTM4 to recycle the water, since the water may be discarded into the environment or used to transfer heat to other processes. Therefore, in one embodiment of the present invention, it is preferable not to directly recycle the heat transfer material flow HTMS4 into the heat exchanger HE1.

[0157] Heat transfer material In Embodiment A, the heat transfer material HTM1 may be any of the heat transfer materials described above. Most preferably, the heat transfer material HTM used in Embodiment A is water.

[0158] In Embodiment A, the heat transfer material flows HTMS1 to 5 are the flows of heat transfer material 1 at different stages of the heat pump HP1. - The heat transfer material flow HTMS1 is the flow of the heat transfer material HTM1 entering process i), - The heat transfer material flow HTMS2 is the flow of the heat transfer material HTM1 that exits process 1) and enters compression process ii). - The heat transfer material flow HTMS3 is the flow of the heat transfer material HTM1 that exits compression step 2) and enters step iii). - The heat transfer material flow HTMS4 is the flow of the heat transfer material HTM1 that exits process iv) and can optionally enter the recycling process R1). - The heat transfer material flow HTMS5 is the flow of the heat transfer material HTM1 exiting the recycling process R1).

[0159] Embodiment B: Serial heat pump In a preferred embodiment B, the transfer of thermal energy from the fluid flow FS1 to the regeneration process c) is carried out by two or more heat pumps connected in series.

[0160] The heat transfer step a) according to Embodiment B is preferably, i) A step of transferring thermal energy from the heat flow HS1 to the heat transfer medium flow HTMS1 of the heat transfer material HTM1 in the heat exchanger HE1 of the first heat pump HP1, and obtaining a heat transfer medium flow HTMS2 having increased thermal energy compared to the heat transfer medium flow HTMS1, ii) A step of compressing the heat transfer medium flow HTMS2 in the first heat pump HP1 to obtain a heat transfer medium flow HTMS3 having a higher pressure than the heat transfer medium flow HTMS2, iii) A step of transferring thermal energy from the heat transfer medium flow HTMS3 of the first heat pump HP1 in the heat exchanger HP2 of the second heat pump HP2 to the second heat transfer medium flow SHTMS1 of the second heat transfer material HTM2, thereby obtaining a second heat transfer medium flow SHTMS2 having increased thermal energy compared to the second heat transfer medium flow SHTMS1, and a heat transfer medium flow HTMS4 having a decreased thermal energy content compared to the heat transfer medium flow HTMS3, iv) A step of compressing the second heat transfer medium flow SHTMS2 in the second heat pump HP2 to obtain a second heat transfer medium flow SHTMS3 having a higher pressure than the second heat transfer medium flow SHTMS2, v) A step of transferring thermal energy from the second heat transfer medium flow SHTMS3 of the second heat pump HP2 to the regeneration step c) to obtain a second heat transfer medium flow SHTMS4 having a reduced thermal energy content compared to SHTMS3, Methods that include...

[0161] Figure 2 shows the process configuration for implementing Embodiment B.

[0162] Process i) Step i) of Embodiment B is preferably carried out substantially in the same manner as step i) of Embodiment A.

[0163] Process ii) Step ii) of Embodiment B is preferably carried out substantially in the same manner as step ii) of Embodiment B.

[0164] Process iii) After increasing the pressure to obtain the heat transfer medium flow HTMS3, in step iii), thermal energy is further transferred from the heat pump HP1 to the heat pump HP2 by transferring thermal energy from the heat transfer medium flow HTMS3 of the first heat pump HP1 to the second heat transfer medium flow SHTMS1 of the second heat pump HP2, thereby obtaining the second heat transfer medium flow SHTMS2 having increased thermal energy compared to the second heat transfer medium flow SHTMS1, and the heat transfer medium flow HTMS4 having decreased thermal energy content compared to the heat transfer medium flow HTMS3.

[0165] The transfer of heat from the heat transfer material flow HTMS3 to the second heat transfer material flow HTMS1 is preferably influenced by the heat exchanger HE2.

[0166] The heat exchanger HE2 is a device used to transfer thermal energy in the form of heat between a heat transfer material flow HTMS3 and a second heat transfer medium flow SHTMS1, in order to obtain a second heat transfer medium flow SHTMS2 having increased thermal energy compared to the heat transfer medium SHTMS1, and a heat transfer material flow HTMS4 having decreased thermal energy compared to the heat transfer material flow HTMS3.

[0167] The heat exchanger HE2 is preferably an indirect heat exchanger.

[0168] If the heat exchanger HE2 is an indirect heat exchanger, HE2 is preferably, - Pressure p at the inlet end of the inlet HTMS3 and temperature T HTMS3 The inlet of the heat transfer medium flow HTMS3 having, - Pressure p at the outlet end of the outlet HTMS3 and temperature T HTMS3 The outlet of the heat transfer medium flow HTMS3 having, - Pressure p at the inlet end of the inlet SHTMS1 and temperature T SHTMS1 The inlet of the second heat transfer medium flow SHTMS1 having, - Pressure p at the outlet of the outlet SHTMS2 and temperature T SHTMS2 The outlet of the second heat transfer medium flow SHTMS2 having, Includes.

[0169] More preferably, the heat exchanger HE2 is a shell-and-tube type exchanger or a plate type exchanger.

[0170] The heat exchanger HE2 is preferably designed in such a way that the following requirements are met: - Temperature T HTMS3 This is substantially higher than the boiling point of the heat transfer material HTM2 in the heat pump HP2 at the regulated pressure, and pressure pSHTMS1 The boiling point of the heat transfer material SHTM1 is preferably 5 to 200 K or higher, preferably 5 to 50 K or higher, and most preferably 5 to 25 K or higher. - Temperature T SHTMS2 is, T SHTMS1 It is approximately 0.1 to 50 K higher than, preferably 0.3 to 15 K, and more preferably 1 to 5 K higher. - The heat transfer material HTM2 in the heat pump HP2 within the second heat transfer material flow SHTMS1 undergoes at least a partial phase transition from liquid to gaseous state. - Pressure p SHTMS1 The pressure p is preferably in the range of about 1 bar. SHTMS1 The pressure can be less than atmospheric pressure, such as 0.1 to 1 bar, but in a preferred embodiment, the pressure p on the side of the second heat transfer material HTM2 is preferable. SHTMS1 The pressure is above atmospheric pressure, preferably in the range of 0.7 to 2 bar, more preferably 0.8 to 1.5 bar, and more preferably 0.9 to 1.2 bar.

[0171] Process iv) In a preferred embodiment, the transfer of heat from the heat pump HP1 to the heat pump HP2, specifically to the second heat transfer medium flow SHTMS2, is preferably followed by a compression step iv) to compress the second heat transfer medium flow SHTMS2 in the second heat pump HP2 to obtain a second heat transfer medium flow SHTMS3 having a higher pressure than the second heat transfer medium flow SHTMS2.

[0172] It is preferable that the compression is affected in the compressor.

[0173] A compressor is a device for increasing the pressure of a gaseous fluid, at least partially.

[0174] Compressors are typically positive displacement compressors or power compressors. Positive displacement compressors include reciprocating compressors that use a piston driven by a crankshaft to deliver fluid at higher pressure. Reciprocating compressors can be single-stage or multi-stage. Positive displacement compressors also include rotary screw compressors, conical screw compressors, rotary vane compressors, rolling piston compressors, or scroll compressors.

[0175] The compressor may also be a powered compressor, such as a centrifugal compressor or an axial flow compressor.

[0176] Preferably, the compressor is a rotary screw compressor, a centrifugal compressor, a piston compressor, or an axial flow compressor.

[0177] Compression can be carried out in one compressor or a series of compressors, depending on the desired pressure increase of the heat transfer material HTM2.

[0178] The heat transfer material HTM2 is subjected to pressure p as the heat transfer material flow SHTMS2. SHTMS2 and temperature T SHTSM2 Then the compression process begins, and the heat transfer material SHTMS3 is subjected to pressure p SHTMS3 and temperature T SHTMS3 Then it exits the compression process.

[0179] Pressure rise Δp(p SHTMS3 -p SHTMS2 The pressure is typically 1 to 20 bar, preferably 1.2 to 10 bar, more preferably 1.5 to 3 bar, and the accompanying temperature rise is preferably 20 to 2000 K, more preferably 25 to 6 K, and most preferably 30 to 50 K.

[0180] In a preferred embodiment, the compression step is performed in a series of two or more compressors, and the heat transfer material HTM2 is water. In this embodiment, an additional flow of heat transfer material HTM2 is supplied after each of the series compressors, increasing the amount of gaseous heat transfer material HTM2 produced at the expense of lowering the flow temperature. In this way, sufficient steam generation for the regeneration step c) can be achieved. In addition, the addition of further heat transfer material HTM2 is energetically preferable compared to a scenario in which the same amount of gaseous heat transfer material HTM2 is produced without the additional heat transfer material HTM2 being introduced after the compression step. Preferably, saturated steam is produced and used for heating the reboiler HE-R. Injecting water between the compressor compartments helps to reduce steam superheating.

[0181] In addition, the injection of the additional heat transfer material HTM2 results in a reduction in volumetric flow rate and a decrease in the power required for subsequent compressors in the continuous compression stage.

[0182] Process v) Transfer of thermal energy from SHTSM3 to regeneration process c) According to a preferred embodiment of the present invention, in step v), thermal energy is transferred from the second heat transfer medium flow SHTMS3 of the second heat pump HP2 to the regeneration step c), thereby obtaining a second heat transfer medium flow SHTMS4 having a reduced thermal energy content compared to SHTMS3.

[0183] The transfer of thermal energy from the second heat transfer material flow SHTMS3 to the regeneration process c) can be carried out indirectly or directly in substantially the same manner as the transfer of thermal energy from the heat transfer material flow HTMS3 to the regeneration process c) in step iv) of Embodiment A.

[0184] Open-loop heat pump In a preferred embodiment of Embodiment B, the last heat pump in a series-connected heat pump is designed as an open-loop heat pump in which the heat transfer material flow leaving heat exchanger HE-R is not recycled to heat exchanger HE-2. This is even more preferred when the heat transfer material used last in the series-connected heat pump is water. Open-loop heat pumps have the aforementioned advantages.

[0185] Recycling process In a further preferred embodiment, Embodiment B includes an additional recycling step R1) to expand the heat transfer medium flow HTMS4 obtained in step iii) of Embodiment B to obtain a heat transfer medium flow HTMS5 having a reduced pressure compared to the heat transfer medium flow HTMS4 and being at least partially recycled to step i) of Embodiment B as a heat transfer medium flow HTMS1.

[0186] The recycling process R1 is carried out substantially in the same manner as the recycling process R1 performed in Embodiment A.

[0187] In a further preferred embodiment, Embodiment B includes an additional recycling step R2) to expand the second heat transfer medium flow SHTMS4 obtained in step v) of Embodiment B to obtain a second heat transfer medium flow SHTMS5 having a reduced pressure compared to the second heat transfer medium flow SHTMS4 and being at least partially recycled in step 3) as a second heat transfer medium flow SHTMS1.

[0188] Expansion is preferably caused by the pressure p of the heat transfer medium flow SHTMS4. SHTMS4 The pressure p of the heat transfer medium flow SHTMS1 SHTMS1 It is affected in order to lower it.

[0189] Expansion is preferably influenced by a thermal expansion valve. Thermal expansion valves that can be used in step 4) are described in the Wikipedia article "Thermal Expansion Valve" at https: / / en.wikipedia.org / wiki / Thermal_expansion_valve.

[0190] p SHTMS4 from p SHTMS5 The reduced pressure Δp causes adiabatic flash evaporation of a portion of the heat transfer medium flow SHTMS4, and the self-cooling effect of adiabatic flash evaporation lowers the temperature of the heat transfer medium flow SHTMS4.

[0191] The expansion valve is p SHTMS5 ga p SHTMS1 Equivalent to, T SHTMS5 is T SHTMS1 It is preferable that it be operated and designed to be equal to [a certain value].

[0192] The heat transfer medium stream SHTMS5 is preferably recycled as the heat transfer material stream SHTMS1 to step 1) of the evaporation process.

[0193] The execution of at least one of the additional recycling steps R1 and R2 in Embodiment B has the advantage of allowing the heat transfer materials HTM1 and HTM2 to be reused in a closed-cycle heat pump in order to save material costs or to prevent environmental pollution associated with the loss of heat transfer materials HTM1 or HTM2 when environmentally harmful heat transfer materials HTM1 or HTM2 are selected.

[0194] If the heat transfer material HTM2 is water / steam, it is not essential to expand the second heat transfer material flow SHTM4 to recycle the water, since the water may be discarded into the environment or used to transfer heat to other processes. However, preferably, the method of the present invention also includes a recycling step R2 if the heat transfer material HTM2 is water or another heat transfer material HTM2, which is particularly preferable in areas where water is a scarce resource.

[0195] Heat transfer material The heat transfer material HTM2 is the working fluid used in the HP2 embodiment B of the heat pump to transport thermal energy from heat exchanger HE2 to heat exchanger HE-R.

[0196] Preferably, the heat transfer material HTM2 can undergo at least a partial phase transition from liquid to gaseous state when transferring thermal energy in the heat exchanger HE2.

[0197] Preferably, the heat transfer material HTM2 can also undergo at least a partial phase transition from gas to liquid state when transferring thermal energy in the heat exchanger HE-R.

[0198] The heat transfer material HTM2 is p SHTMS1 The boiling point at p HTMS3 T in HTMS3 It is preferable that the substance is lower than the temperature at which the regenerator operates.

[0199] Therefore, in addition to water, pressure p SHTMS1 Any other substance having a boiling point of less than 150°C, preferably less than 140°C, and more preferably less than 130°C is preferred.

[0200] Since water can undergo at least a partial phase transition to steam in the heat exchanger HE2, water is the most preferred heat transfer material HTM2.

[0201] The heat transfer material HTM1 used in the heat pump HP1 of Embodiment B preferably has a lower boiling point than the heat transfer material HTM2 under the conditions of the heat pump HP1. Preferably, HTM1 can be selected from the group consisting of ammonia, butane, R123zd(e), R1224yd(z), air, CO2, water, chlorofluorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, hydrofluoroolefin, hydrochlorofluoroolefin, hydrocarbon, and perfluoro(2-methyl-3-pentanone).

[0202] In Embodiment B, it is preferable that the heat transfer material HTM1 be either ammonia or butane, and the heat transfer material HTM2 be a combination of water.

[0203] In Embodiment B, the heat transfer material flows HTMS1 to 5 are the flows of heat transfer material 1 at different stages of the heat pump HP1. - The heat transfer material flow HTMS1 is the flow of the heat transfer material HTM1 entering process i), - The heat transfer material flow HTMS2 is the flow of the heat transfer material HTM1 that exits process 1) and enters compression process ii). - The heat transfer material flow HTMS3 is the flow of the heat transfer material HTM1 that exits compression step 2) and enters step iii). - The heat transfer material flow HTMS4 is the flow of the heat transfer material HTM1 that exits process iv) and can optionally enter the recycling process R1). - The heat transfer material flow HTMS5 is the flow of the heat transfer material HTM1 exiting the recycling process R1). - The second heat transfer material flow SHTMS1 is the flow of the heat transfer material HTM2 entering step 3), - The second heat transfer material flow SHTMS2 is the flow of heat transfer material HTM2 that exits process 3) and enters the compression process 4). - The second heat transfer material flow SHTMS3 is the flow of heat transfer material HTM2 that exits compression step 4) and enters step 5). - The second heat transfer material flow SHTMS4 is a flow of heat transfer material HTM2 that exits process 5) and can optionally enter the recycling process R2). - The second heat transfer material flow SHTMS5 is a flow of heat transfer material HTM2 that exits cycle process R2) and can be recycled back to process 3) as the second heat transfer material flow SHTMS1.

[0204] Embodiment C): Modified heat pump Embodiment C utilizes a so-called modified heat pump in which heat transfer from the fluid flow FS1 to the heat transfer medium flow HTMS1 is affected within the heat exchanger HE1 in order to obtain the liquid heat transfer medium flow HTMS2a, and the evaporation of HTMS2a is carried out by a separate evaporation means as described below.

[0205] Embodiment C has the advantage of also being able to produce steam directly from the fluid flow FS1. This enables thermal integration of flows that cannot directly produce steam. In addition, the process including the modified heat pump can be designed to have relatively low operating and capital costs.

[0206] The heat transfer step a) of Embodiment C is preferably, (i) A step of transferring thermal energy from the fluid flow FS1 to the liquid heat transfer material flow HTMS1 of the heat transfer material HTM1 in a direct contact type cooler to obtain the liquid heat transfer material flow HTMS2a, (ii) A step of expanding the heat transfer medium flow HTMS2a in one or more expansion steps to obtain a gaseous heat transfer material flow HTMS2b(g) having a pressure lower than that of the heat transfer material flow HTMS2a, (iii) A step of compressing the heat transfer material flow HTMS2b(g) in one or more compression steps to obtain a gaseous heat transfer material flow HTMS3b having a higher pressure than the heat transfer material flow HTMS2(g), (iv) A step of transferring thermal energy from the heat transfer material flow HTMS3 to the regeneration step c) to obtain the heat transfer material flow HTMS4, Includes.

[0207] Process i) In step i) of Embodiment C, the transfer of thermal energy from the fluid flow FS1 to the heat transfer material flow HTMS1 in the modified heat pump can be carried out directly or indirectly.

[0208] Figure 3 shows the process configuration of Embodiment C, in which heat transfer occurs directly from the fluid flow FS1 to the heat transfer material flow.

[0209] Figure 4 shows the process configuration of Embodiment C, which involves indirect heat transfer via a cooling medium cycle including cooling medium flows CMS1, CMS2, and CMS3.

[0210] Direct heat transfer can be carried out substantially in the same manner as in step i) of Embodiment A, provided that the cooling material CM1 used in the direct contact cooler is the heat transfer material HTM1 of the modified heat pump.

[0211] Therefore, direct contact cooling includes the transfer of thermal energy from the fluid flow FS1 to the heat transfer material flow HTMS1 in order to obtain a heat transfer material flow HTMS2a having higher thermal energy than the heat transfer material flow HTMS1. Thus, the heat transfer material flow HTMS1 and the heat transfer material flow HTMS2a correspond to the cooling medium flow CMS1 and the cooling medium flow CMS2 in step i) of Embodiment A.

[0212] Heat transfer from the fluid flow FS1 can also occur indirectly. Indirect heat transfer can be carried out substantially in the same manner as steps i) and ii) in Embodiment A, provided that a phase transition of the heat transfer material HTM1 in the heat exchanger HE1 does not occur in step i) and a liquid heat transfer material flow HTMS2a is obtained.

[0213] Step i) of Embodiment C brings forth a liquid heat transfer material flow HTMS2a.

[0214] Process ii) After transferring thermal energy to the heat transfer material flow HTMS2a, the liquid heat transfer material flow HTMS2a is expanded in one or more expansion steps to obtain a gaseous heat transfer material flow HTMS2b(g) having a lower pressure than the heat transfer material flow HTMS2a.

[0215] The expansion process is preferably carried out by means suitable for influencing such expansion. The expansion is preferably p HTMS2a This is carried out as flash evaporation of the heat transfer material flow HTMS2a via an expansion valve or throttle valve into a container having a pressure lower than that. The container preferably has a liquid outlet and a vapor outlet. More preferably, the container is a flash drum. The flow of heat transfer material HTMS2a, HTMS2a(l), which remains in liquid form after evaporation, is preferably recycled to step i) as heat transfer material flow HTMS1, as will be further described below.

[0216] In evaporation step ii), the pressure is preferably reduced to a value of 10 to 900 mbar, preferably 30 to 700 mbar, and more preferably 50 to 300 mbar.

[0217] Pressure drop can be affected in one or more evaporation processes.

[0218] The pressure drop typically results in a temperature drop of preferably 2-30K, more preferably 3-20K, and most preferably 5-15K, and partial evaporation of the heat transfer material flow HTMS2a, yielding a gaseous heat transfer material flow HTMS2b(g), while the remaining portion of the heat transfer material flow HTMS2a remains in a liquid state, yielding a liquid heat transfer material flow HTMS2b(l). Due to the pressure drop, typically about 0.5-10, preferably 1-8, and more preferably 2-5 weight percent of the original mass of the heat transfer material flow HTMS2a undergoes a phase transition to a gaseous state. The liquid portion of the heat transfer material flow HTMS2b(l) is preferably recycled to the heat exchanger HE1 as the heat transfer material flow HTMS1 in step i) or step ia), respectively. It may be necessary to perform one or more compression or cooling steps to impart the characteristics of the heat transfer material flow HTMS1 to the liquid portion of the heat transfer material flow HTMS2b(l). Preferably, the heat transfer material flow HTMS2b(l) is cooled by a heat exchanger HE-RS, which is preferably a water or air cooler.

[0219] Process iii) After expanding the heat transfer medium flow HTMS2a to obtain the heat transfer material flow HTMS2b(g), the thermal energy is further transferred, preferably in step iii), by compressing the heat transfer medium flow HTMS2b(g) in the heat pump HP1 to obtain a heat transfer medium flow HTMS3 having a higher pressure than the heat transfer medium flow HTMS2b(g).

[0220] It is preferable that the compression is affected in the compressor.

[0221] A compressor is a device for increasing the pressure of a gaseous fluid, at least partially.

[0222] The compressor is typically a positive displacement compressor or a dynamic compressor. Positive displacement compressors include reciprocating compressors that use a piston driven by a crankshaft to deliver a fluid at a higher pressure. Reciprocating compressors can be single-stage or multi-stage. Positive displacement compressors also include rotary screw compressors, conical screw compressors, rotary vane compressors, rolling piston compressors, or scroll compressors.

[0223] The compressor can also be a dynamic compressor such as a centrifugal compressor or an axial flow compressor.

[0224] Preferably, the compressor is a rotary screw compressor, a centrifugal compressor, a piston compressor or an axial flow compressor.

[0225] Compression can be carried out with one compressor or a series of compressors in response to the desired pressure increase of the heat transfer medium HTM1.

[0226] The heat transfer medium HTM1 enters the compression process as the heat transfer medium flow HTMS2b(g) at a pressure p HTMS2b and a temperature T HTSM2b and exits the compression process as the heat transfer medium HTMS3 at a pressure p HTMS3 and a temperature T HTMS3

[0227] The pressure increase Δp (pHTMS3 - pHTMS2b) in the compression process is typically selected such that the temperature of the heat transfer medium flow rises to the temperature required in the regeneration process b). Preferably, the pressure increase Δp is selected such that in the heat exchanger HE-R, which is the reboiler of the regenerator in process b), it reaches a temperature of 100 to 150 °C, preferably 105 to 140 °C, most preferably 110 to 130 °C.

[0228] ​In a preferred embodiment, the compression step iii) is carried out in a series of two or more compressors, and the heat transfer medium HTM1 is water. In this embodiment, an additional flow of the heat transfer medium HTM1 is additionally supplied after each of the compressors in series, sacrificing a reduction in the temperature of the flow to increase the amount of gaseous heat transfer medium HTM1 produced. In this way, sufficient steam generation for the regeneration step c) can be achieved. In addition, the addition of further heat transfer medium HTM1 is energetically preferred compared to a scenario where the same amount of gaseous heat transfer medium HMT1 is produced without the additional heat transfer medium HMT1 being introduced after the compression step. Preferably, saturated steam is produced and used for heating the reboiler HE-R. Injecting water between the compressor sections helps to reduce the superheat of the steam. In addition, the injection of additional heat transfer medium HTM1 results in a reduction in the volumetric flow rate and the required power of the subsequent compressors in the continuous compression stage.

[0229] Step iv): In Embodiment C, in step iv), heat energy is transferred to the regeneration step c) by transferring heat energy from the heat transfer medium flow HTMS3 to the regeneration step c), obtaining a heat transfer medium flow HTMS4 having a reduced heat energy content compared to HTMS3.

[0230] The transfer of heat energy from the heat transfer medium flow HTMS3 to the regeneration step c) can be carried out indirectly or directly, as described in step iv) of Embodiment A.

[0231] Open-loop heat pump In a preferred embodiment of Embodiment C, the modified heat pump is designed as an open-loop heat pump in which the heat transfer medium flow HTM4 exiting the heat exchanger HE-R is not recycled to the heat exchanger HE1. This is even more preferably applicable when the heat transfer medium used last among the heat pumps connected in series is water. The open-loop heat pump has the advantages described above.

[0232] Use of HTMS4 The heat transfer material HTM4 in Embodiment C can also be recycled or reused to provide heat to other parts of the process or other heat consumers.

[0233] Recycling may require an additional cooling step to cool the heat transfer material flow HTMS4 obtained at the outlet of the heat exchanger HE-R before recycling it as a heat transfer material flow HTMS1 or a cooling medium flow CMS1. The cooling step preferably includes heat transfer to a part of the process that requires additional heat. For example, the heat transfer material flow HTMS4 may be additionally used to heat the loaded absorbent flow A2 before its introduction into the regeneration step c).

[0234] Alternatively, the heat transfer material flow HTMS4 may be used in other processes at the AGRU or other heat consumer location to provide heat.

[0235] In a more preferred embodiment, the heat transfer material flow HTMS4 may be mixed with the heat transfer material flow HTMS2a. In this case, the heat transfer material flow HTMS2 or the cooling medium flow CMS1 may need to be supplemented with fresh heat transfer material HTM1 or fresh cooling medium CM1.

[0236] Heat transfer material HTM1 In the modified heat pump, the heat transfer material HTM1 used is preferably water, especially when the cooling medium CM1 of the direct-contact cooler is also the heat transfer material HTM1 of the modified heat pump HP1. In this case, steam can be produced directly from the cooling medium flow CMS1 by steps ii) and iii) of Embodiment C. This embodiment requires relatively little investment and can be easily implemented.

[0237] Acid gas absorption process - Absorption step b) According to the present invention, the fluid flow FS2 obtained in energy transfer step a) is deoxidized in absorption step b) by bringing the cooled fluid flow FS2 into contact with absorbent A1 in the absorber to obtain absorbent A2 loaded with an acidic gas and at least partially deoxidized fluid flow.

[0238] Absorbent: The absorbent contains at least one amine. The following amines are preferred: i) Amine of formula I: NR 1 (R 2 )2(I) In the formula, R 1 is selected from a C2-C6-hydroxyalkyl group, a C1-C6-alkoxy-C2-C6-alkyl group, a hydroxy-C1-C6-alkoxy-C2-C6-alkyl group, and a 1-piperazinyl-C2-C6-alkyl group, and R 2 is independently selected from H, a C1-C6-alkyl group, and a C2-C6-hydroxyalkyl group; ii) Amine of formula II: R 3 R 4 N-X-NR 5 R 6 (II) In the formula, R 3 , R 4 , R 5 and R 6 are independently selected from H, a C1-C6-alkyl group, a C2-C6-hydroxyalkyl group, a C1-C6-alkoxy-C2-C6-alkyl group, and a C2-C6-aminoalkyl group, X is a C2-C6-alkylene group, -X 1 -NR 7 -X 2 - or -X 1 -O-X 2 -, where X 1 and X 2 are independently a C2-C6-alkylene group, and R 7 is H, a C1-C6-alkyl group, a C2-C6-hydroxyalkyl group, or a C2-C6-aminoalkyl group; iii) A 5- to 7-membered saturated heterocyclic ring having at least one nitrogen atom in the ring and optionally containing one or two further heteroatoms selected from nitrogen and oxygen in the ring, and iv) mixtures thereof.

[0239] Specific examples of amines that can be preferably used are as follows: i) 2-aminoethanol (monoethanolamine), 2-(methylamino)ethanol, 2-(ethylamino)ethanol, 2-(n-butylamino)ethanol, 2-amino-2-methylpropanol, N-(2-aminoethyl)piperazine, methyldiethanolamine, ethyldiethanolamine, dimethylaminopropanol, t-butylaminoethoxyethanol (TBAEE), 2-amino-2-methylpropanol, diisoproanolamine (DIPA), ii) 3-methylaminopropylamine, ethylenediamine, diethylenetriamine, triethylenetetramine, 2,2-dimethyl-1,3-diaminopropane, hexamethylenediamine, 1,4-diaminobutane, 3,3-iminobispropylamine, tris(2-aminoethyl)amine, bis(3-dimethylaminopropyl)amine, tetramethylhexamethylenediamine, iii) Piperazine, 2-methylpiperazine, N-methylpiperazine, 1-hydroxyethylpiperazine, 1,4-bishydroxyethylpiperazine, 4-hydroxyethylpiperidine, homopiperazine, piperidine, 2-hydroxyethylpiperidine, triethylenediamine (TEDA) and morpholine, and iv) A mixture of those.

[0240] In preferred embodiments, the absorbent comprises at least one of amine monoethanolamine (MEA), methylaminopropylamine (MAPA), piperazine (PIP), diethanolamine (DEA), triethanolamine (TEA), diethylethanolamine (DEEA), diisopropanol (DIPA), aminoethoxyethanol (AEE), tert-butylaminoethoxyethanol (TBAEE), dimethylaminopropanol (DIMAP), and methyldiethanolamine (MDEA), triethylenediamine (TEDA), or a mixture thereof.

[0241] Further amines that can be introduced into this process are tert-butylaminopropanediol, tert-butylaminoethoxyethylmorpholine, tert-butylaminoethylmorpholine, methoxyethoxyethoxyethyl-tert-butylamine, and tert-butylaminoethylpyrrolidone.

[0242] The amine is preferably a sterically hindered amine or a tertiary amine. A sterically hindered amine is a secondary amine in which the amine nitrogen is bonded to at least one secondary carbon atom and / or at least one tertiary carbon atom, or a primary amine in which the amine nitrogen is bonded to a tertiary carbon atom. A preferred sterically hindered amine is t-butylaminoethoxyethanol. Preferred tertiary amines are methyldiethanolamine and triethylenediamine (TEDA).

[0243] When the objective is to completely or substantially completely remove CO2 present in a fluid flow, the absorbent preferably further contains an activator when the amine present in the absorbent is a sterically hindered amine or a tertiary amine. The activator is generally a sterically unhindered primary or secondary amine. In these sterically unhindered amines, at least one amine nitrogen of an amino group is bonded only to primary carbon and hydrogen atoms. When the objective is simply to remove a portion of the gas present in a fluid flow, for example, to selectively remove H2S from a fluid flow containing H2S and CO2, the absorbent preferably contains no activator.

[0244] Sterically unhindered primary or secondary amines that can be used as activators include, for example, alkanolamines such as monoethanolamine (MEA), diethanolamine (DEA), ethylaminoethanol, 1-amino-2-methyl-propan-2-ol, 2-amino-1-butanol, 2-(2-aminoethoxy)ethanol, and 2-(2-aminoethoxy)ethaneamine, polyamines such as hexamethylenediamine, 1,4-diaminobutane, 1,3-diaminopropane, 3-(methylamino)propylamine (MAPA), N-(2-hydroxyethyl)ethylenediamine, 3-(dimethylamino)propylamine (DMAPA), 3-(diethylamino)propylamine, N,N'-bis(2-hydroxyethyl)ethylenediamine, 5-membered, 6-membered or 7-membered saturated heterocycles having at least one NH group in the ring and optionally containing one or two additional heteroatoms selected from nitrogen and oxygen, such as piperazine, 2-methylpiperazine, N-methylpiperazine, N-ethylpiperazine, N-(2-hydroxyethyl)piperazine, N-(2-aminoethyl)piperazine, homopiperazine, piperidine and morpholine.

[0245] Particularly preferred are 5-membered, 6-membered or 7-membered saturated heterocycles having at least one NH group in the ring and optionally containing one or two additional heteroatoms selected from nitrogen and oxygen. Most particularly preferred is piperazine.

[0246] The molar ratio of the activator to the sterically hindered amine or tertiary amine is preferably in the range of 0.05 to 1.0, more preferably in the range of 0.05 to 0.7.

[0247] The absorbent generally contains 10% to 60% by weight of the amine.

[0248] In one embodiment, the absorbent contains methyldiethanolamine, which is a tertiary amine, and piperazine, which is an activator.

[0249] In a preferred embodiment, the absorbent is A) At least one cyclic amine compound having only tertiary amine groups, and B) comprising at least one cyclic amine compound having at least one sterically unhindered secondary amine group, The total concentration of A) + B) is 10-60% by weight.

[0250] Such absorbents are disclosed in European Patent No. 2391435. Most preferably, amine A) is triethylenediamine (TEDA) and activator amine B) is piperazine.

[0251] The absorbent may further contain a physical solvent. Suitable physical solvents include, for example, N-methylpyrrolidone, tetramethylene sulfone, oligoethylene glycol dialkyl ethers, such as oligoethylene glycol methyl isopropyl ether (SEPASOLV MPE) and oligoethylene glycol dimethyl ether (SELEXOL). The physical solvent is generally present in the absorbent in an amount of 1% to 60% by weight, preferably 10% to 50% by weight, and particularly 20% to 40% by weight.

[0252] In preferred embodiments, the absorbent contains less than 10% by weight, for example, less than 5% by weight, and particularly less than 2% by weight, of an inorganic basic salt such as potassium carbonate.

[0253] The absorbent may also contain additives such as corrosion inhibitors, antioxidants, enzymes, and defoamers. Generally, the amount of such additives is in the range of approximately 0.01 to 3% by weight of the absorbent.

[0254] The absorber may be supplied with fresh absorbent material, or it may be supplied with recycled absorbent material from recycling process c). Supplying fresh absorbent material means that the components of the absorbent material have not yet passed through processes b) to d). Supplying recycled absorbent material requires that at least some of the components of the absorbent material have passed through processes b) to d).

[0255] The absorbent is preferably aqueous. This means that a variety of different components of the absorbent, such as amines, methanol, physical solvents, and additives, can be mixed with water in the amounts mentioned above.

[0256] Absorber: It is preferable to bring the fluid flow FS2 into contact with the absorbent in the absorber in step b).

[0257] The absorber is preferably an absorption tower or absorption column, for example, a column having random packing or structured packing, or a tray column.

[0258] Absorbers generally include an absorption zone and optionally a rewashing zone.

[0259] The absorption zone is considered to be the section of the absorption column where the fluid flow comes into mass transfer contact with the absorbent.

[0260] It is preferable that the fluid flow contacts the absorbent in a countercurrent direction within the absorption zone.

[0261] To improve contact with the absorbent and provide a large mass transfer interface, the absorbent zone generally includes an internal structure, such as random packing, structured packing, and / or a tray, such as a valve tray, bubble cap tray, Souman tray, or sieve tray.

[0262] If the absorption zone includes random packing or structured packing, the height of the random packing / structured packing in the absorption zone is preferably in the range of 5 to 20 m, more preferably in the range of 6 to 15 m, and most preferably in the range of 8 to 14 m.

[0263] If the absorption zone includes trays, the number of trays in the absorption zone is preferably in the range of 8 to 30, more preferably 12 to 25, and most preferably 15 to 23.

[0264] For columns with random or structured packing, the absorption zone may be divided into one or more compartments, preferably two to four. Support and retention trays and / or distribution trays may be placed between the individual compartments of the absorption zone, which improve the distribution of the absorbent across the entire cross-section of the column.

[0265] The temperature of the absorbent introduced into the absorption zone is generally about 0 to 60°C, preferably 10 to 50°C, and more preferably 25 to 50°C.

[0266] The pressure inside the absorber depends on the pressure and type of the fluid flow FS2 entering the absorber.

[0267] When the fluid flow FS2 is synthesis gas, the pressure inside the absorber is typically in the range of 5 to 120 bar, more preferably 10 to 100 bar, and most preferably 10 to 60 bar.

[0268] When the fluid flow FS2 is exhaust gas, the pressure inside the absorber is typically in the range of 0.7 to 1.5 bar, more preferably 0.8 to 1.3 bar, and more preferably 0.9 to 1.2 bar. Most preferably, the absorber operates at atmospheric pressure when the fluid flow FS2 is exhaust gas.

[0269] The supply point of the introduced fluid flow is preferably below or within the lower region of the absorption zone. The supply is preferably distributed uniformly across the cross-section of the absorber via a gas distributor.

[0270] The absorber may include one or more supply points for the absorbent to be introduced. For example, the absorber may include a supply point for fresh absorbent A1 and a supply point for regenerated absorbent A3. Alternatively, the fresh and regenerated absorbent may be supplied together to the absorber through a single supply point. The one or more supply points are preferably above or within the upper region of the absorption zone. Individual components of the absorbent, such as makeup water, may also be supplied through the supply point for the fresh absorbent.

[0271] If the absorber has an optional rewashing zone, the supply unit is preferably located between the absorber zone and the rewashing zone.

[0272] In the absorption zone, the fluid flow and the absorbent come into contact, providing at least partially deoxidized fluid flow FS3 and an absorbent loaded with an acidic gas.

[0273] Generally, the upper region of the absorber has an extraction point for the deoxidized fluid flow FS3. A demister may be installed within the extraction point region to separate any liquid residue of the absorbent or detergent from the outgoing fluid flow.

[0274] Generally, the extraction point for the loaded absorbent FS2 is located in the lower region of the absorber, preferably at the bottom.

[0275] The fluid stream FS3, which has been at least partially deoxidized, may optionally come into contact with a cleaning liquid in one or more re-cleaning zones (collectively referred to as “re-cleaning zones”).

[0276] The cleaning liquid is more preferably an aqueous liquid. The cleaning liquid may be a process-specific liquid, i.e., an aqueous liquid obtained elsewhere in the process, or an aqueous liquid supplied from an external source. Preferably, the cleaning liquid contains condensate (referred to as absorber upper condensate) and / or fresh water formed in a cooling operation downstream of the deacidified fluid flow.

[0277] The re-washing zone is generally the section of the absorber above the absorbent supply point.

[0278] The rewashing zone preferably has random packing, structured packing, and / or trays to enhance contact between the fluid flow and the cleaning liquid. The rewashing zone may, in particular, have trays, especially valve trays, bubble cap trays, Souman trays, or sieve trays.

[0279] The rewashing zone preferably includes 1 to 7 trays, more preferably 2 to 6, most preferably 3 to 5 trays, or a packing height of preferably 1 to 6 m, more preferably 2 to 5, most preferably 2 to 3 m (random packing / structured packing).

[0280] The cleaning fluid is generally introduced above the re-cleaning zone or into the upper region of the re-cleaning zone. The cleaning fluid used may be the cleaning fluid described above.

[0281] The cleaning fluid can be recycled through a re-cleaning zone. This is achieved by collecting the cleaning fluid below the re-cleaning zone, for example, by a suitable collection tray, and pumping it to the upper end of the re-cleaning zone. The recycled cleaning fluid can be cooled to a temperature of preferably 20°C to 70°C, particularly 30°C to 60°C. This is advantageously achieved by circulating the cleaning fluid through a cooler. To avoid any accumulation of the absorbent components removed during cleaning in the cleaning fluid, it is preferable that the by-flow of the cleaning fluid be discharged from the re-cleaning zone.

[0282] Contact between the at least partially deoxidized fluid stream FS3 and the cleaning liquid makes it possible to wash away entrained absorbent components such as amines. Contact with an aqueous cleaning liquid can further improve the water balance of the process when more water is discharged by the outflow than is introduced by the inflow.

[0283] The deoxidized fluid flow FS3 described above is preferably withdrawn through the withdrawal point at the top of the absorber.

[0284] Optionally, the deoxidized fluid flow FS3 can be guided through a condenser.

[0285] The condensers used may be, for example, condensers having cooling coils or helical tubes, plate heat exchangers, jacketed tube condensers, and shell-and-tube heat exchangers.

[0286] The condenser is generally operated at a temperature in the range of 10 to 60°C, preferably 20 to 50°C, and more preferably 20 to 30°C.

[0287] The water content of a deoxidized fluid stream is generally 80-100% of the saturation concentration of water in the fluid stream under existing temperature and pressure conditions.

[0288] Step b) provides an absorbent A2 that is at least partially loaded with an acidic gas.

[0289] The loaded absorbent A2 can be supplied directly to the regeneration process c).

[0290] Expansion process (optional): In a particular embodiment of the process of the present invention, the expansion step is performed first on the loaded absorbent A2 before it is introduced into the regeneration step c).

[0291] In the expansion process, the loaded adsorbent A2 is generally guided into one or more expansion containers.

[0292] If the pressure inside the absorber is higher than the pressure inside the regenerator, the loaded absorbent can be expanded into the expansion container through the throttle valve.

[0293] If the fluid flow FS2 is syngas, the loaded adsorbent is preferably expanded to a pressure of 3 to 15 bar, preferably 4 to 12, and more preferably 5 to 10 bar.

[0294] Expansion generally leads to the desorption of so-called flash gas. This flash gas can be absorbed back into the compressor, incinerated for energy generation, or flared in place.

[0295] If the fluid flow FS2 is exhaust gas, the loaded absorbent is preferably pumped to an expansion vessel located downstream of the cross-flow heat exchanger HE-CF. In this case, the pump can typically increase the pressure of the fluid flow FS2 by about 2-8 barg, and expand it into the expansion vessel, which preferably operates at a pressure slightly above the regenerator pressure. The effect of the expansion step is usually enhanced by the temperature increase of the fluid flow FS2 as it passes through the cross-flow heat exchanger HE-CF. Performing the additional expansion step has the advantage that at least some of the oxygen contained in the fluid flow FS2, which would adversely affect the required CO2 purity, can be flash-removed.

[0296] A flash container is generally a container that does not contain any specific internal structure. A flash container is preferably a so-called flash drum. Alternative flash containers include columns having internal structures, such as random packing, structured packing, or trays.

[0297] The upper region of the flash vessel generally contains a gas extraction section for the gas converted to the gas phase. Furthermore, it is preferable that a demister be positioned in the gas extraction region. If necessary, any existing acidic gases may be separated from the flash gas in an additional absorption column. Typically, for this purpose, a sidestream of regenerated solvent is supplied to the additional absorption column.

[0298] Generally, absorbent A2, which is at least partially loaded with an acidic gas that has not yet been converted to the gas phase, is withdrawn at the base of the flash container and generally guided to regeneration step c).

[0299] Regeneration process c): According to the present invention, the adsorbent A2, which has been at least partially loaded with an acidic gas, is supplied to a regeneration step C) in which at least a portion of the loaded absorbent A2 obtained from step b) is regenerated in a regenerator to obtain at least partially regenerated absorbent A3 and a gas flow GS containing at least one acidic gas.

[0300] The gaseous flow GS may contain residual moisture that was not separated in the rewashing zone.

[0301] Before being introduced into regeneration step c), it is preferable that the adsorbent A2, which has been at least partially loaded with acidic gas, be guided through the cross-flow heat exchanger HE-CF.

[0302] In the cross-flow heat exchanger HE-CF, the absorbent A2, which is at least partially loaded with an acidic gas, is heated to a temperature preferably in the range of 50 to 150°C, more preferably 70 to 130°C, and most preferably 80 to 110°C. In certain embodiments, the regenerated absorbent A3, which is extracted from the bottom of the regenerator, is used as a heat transfer medium in the heat exchanger HE-CF. This embodiment has the advantage that the thermal energy of the regenerated absorbent A3 from step c) can be used to heat the loaded absorbent A2 from step b) in the heat exchanger HE-CF. In this way, it is possible to further reduce the overall process energy cost and the energy requirement in the reboiler of regeneration step c).

[0303] In a more preferred embodiment, as described in more detail above, the second heat transfer material flow SHTMS3 is used as a heat transfer medium in the heat exchanger HE-R in addition to or instead of the cross-flow heat exchanger HE-CF.

[0304] Regenerator: According to the present invention, the regeneration process is performed in a regenerator.

[0305] The regenerator is generally configured as a stripping column.

[0306] The regenerator preferably includes a regeneration zone and a reboiler.

[0307] The regenerator is preferably operated at a top pressure in the range of 0.5 to 5 bar, preferably 0.7 to 4 bar, and more preferably 0.9 to 2.5 bar.

[0308] Generally, a liquid extraction port for the regenerated absorbent A3 is located at the bottom of the regenerator.

[0309] Generally, the top of the regenerator has a gas extraction port for the gas flow GS. It is preferable that the demister is attached to the area of ​​the gas extraction port.

[0310] A regenerator generally has a regeneration zone located above the bottom and below the rewashing zone. In this context, the regeneration zone is considered to be the area of ​​the regenerator where the loaded absorbent comes into contact with the steam produced in the reboiler.

[0311] To improve contact and provide a large mass transfer interface, the regeneration zone generally includes internal structures such as random packing, structured packing, and / or trays such as valve trays, bubble cap trays, Souman trays, or sieve trays.

[0312] If the regeneration zone includes structured or random fillers, the height of the structured / random fillers in the regeneration zone is preferably in the range of 5 to 15 m, more preferably in the range of 6 to 12 m, and most preferably in the range of 8 to 12 m.

[0313] If the regeneration zone includes trays, the number of trays in the regeneration zone is preferably in the range of 10 to 30, more preferably 15 to 25, and most preferably 17 to 23.

[0314] In the case of columns with random or structured packing, the regeneration zone may be further divided into, preferably, two to four, compartments. Support and retention trays and / or distribution trays may be placed between the compartments of the regeneration zone, which improve the distribution of liquid across the entire cross-section of the regenerator.

[0315] Generally, it is preferable that the loaded absorbent A2 is introduced into the regenerator in the upper region, or above the regeneration zone and below the rewashing zone.

[0316] In the regeneration zone, the vapor generated in the evaporator is generally acted against the absorbent flowing downward through the regeneration zone.

[0317] The regenerator zone located below the regeneration zone is generally referred to as the bottom.

[0318] In this region, the absorbent is typically collected and (i) supplied to the reboiler HE-R via a pipeline through the liquid extraction section in the lower region of the regenerator as absorbent stream AS1, and / or (ii) partially recycled back into the absorber as regenerated absorbent A3.

[0319] The bottom section may be divided by a collection tray positioned between the bottom extraction section and the supply point for the steam produced in the evaporator.

[0320] Generally, at least a portion of the regenerated absorbent A3 is guided as absorbent stream AS1 from the bottom outlet of the regenerator to the reboiler.

[0321] Preferably, the bottom discharge portion from the regenerator is completely guided to the reboiler as an absorbent flow AS1.

[0322] Reboilers (HE-R) are typically kettle-type reboilers, natural circulation reboilers, thermal siphon reboilers, or forced circulation reboilers.

[0323] The reboiler HE-R of the regenerator is preferably located outside the regenerator and connected to the bottom extraction section via a pipeline.

[0324] The reboiler HE-R is generally operated at temperatures in the range of 100-150°C, preferably 105-140°C, and most preferably 110-130°C.

[0325] In a reboiler HE-R, generally, at least a portion of the bottom extraction section evaporates and is returned to the regenerator as an absorbent stream AS2. The absorbent stream AS2 is preferably supplied to the regenerator located below the regeneration zone, and preferably to the bottom of the regenerator.

[0326] If an additional collection tray is located at the bottom, it is preferable that the steam produced in the reboiler be supplied below the collection tray.

[0327] Re-cleaning zone: In a preferred embodiment, the regenerator has a rewashing zone above the regeneration zone, and particularly preferably above the supply point of the loaded absorbent A2.

[0328] The re-cleaning zone generally takes the form of a compartment in the regenerator located above the regeneration zone.

[0329] The re-cleaning zone preferably has internal structures, in particular random packing, structured packing, and / or trays, to enhance contact between the fluid flow and the cleaning liquid. Particularly preferably, the cleaning compartment has trays, in particular valve trays or bubble cap trays.

[0330] In a preferred embodiment, the internal structure is random filler and / or structured filler. The filler height (random filler / structured filler) is preferably in the range of 1 to 10, more preferably 2 to 8, and most preferably 3 to 6 m.

[0331] In a particularly highly preferred embodiment, the rewashing zone has trays, especially valve trays or bubble cap trays, and the number of trays is preferably in the range of 2 to 10, more preferably 2 to 8, and most preferably 2 to 6 trays.

[0332] The cleaning fluid may be introduced into the upper area of ​​the re-cleaning zone or above the re-cleaning zone.

[0333] The cleaning liquid used is generally aqueous or slightly acidic aqueous solution, especially water. The temperature of the cleaning liquid is generally in the range of 10 to 60°C, preferably 20 to 55°C, and more preferably 30 to 40°C.

[0334] In the rewashing zone, the amount of entrained residual amines can be washed away from the absorbent so that the acidic off-gas GS exiting the regenerator is essentially free of amines. In the rewashing zone, some condensation of water vapor may occur due to contact with a lower-temperature cleaning agent, which can further reduce the water content of the gas stream obtained at the top of the regenerator.

[0335] Condensation process: In a preferred embodiment of the present invention, the acidic gas stream GS from the regenerator is introduced into the condensation process.

[0336] In the condensation process, the condensate containing water is condensed from the gas flow (condensate outlet). The uncondensed gas phase is preferably discharged into the compression process, as will be further explained below.

[0337] The condensation process is preferably carried out so that the gas flow GS from stage c) is guided through one or more condensers (regenerator top condensers). The top condenser generally includes a heat exchanger and a vessel (phase separation vessel) in which the liquid phase can be separated from the gas phase. However, the heat exchanger and the vessel may also be integrated into a single component.

[0338] The top condenser of a regenerator is generally operated so that acidic gases remain primarily in the gas phase while water condenses.

[0339] The regenerator top condenser used may be, for example, a condenser having a cooling coil or helical tube, a jacketed tube condenser, or a shell-and-tube heat exchanger.

[0340] The regenerator top condenser is generally operated at a temperature in the range of 10 to 60°C, preferably 20 to 55°C, and more preferably 30 to 40°C.

[0341] In a preferred embodiment, the gas flow GS from stage c) is guided through one regenerator top condenser.

[0342] Optionally, the cleaning liquid described above can be additionally introduced into the regenerator along with the condensate from the condensation process. This introduction can be done through the same supply point. Alternatively, the cleaning liquid can be introduced through a separate supply point.

[0343] Compression and / or liquefaction process: The fluid flow GS preferably contains CO2.

[0344] To prevent such CO2 from being released into the atmosphere, it is preferable that the CO2 be isolated in a suitable storage location.

[0345] For isolation, it is generally necessary to compress the gaseous CO2 flow GS and optionally cool it to a fluid, which can then be transported through a pipeline to its destination, or transported as a chemical to a destination where the fluid will be used for further applications. Typical CO2 pressures in transport pipelines are 70–200 bar, preferably 90–150 bar. Typical CO2 pressures for transport by ship, truck, or train are 5–50 bar, preferably 6–40, more preferably 7–35 bar.

[0346] Compression is typically affected by one or more compressors. A compressor is typically configured to receive CO2 containing a gaseous flow GS and compress the gaseous flow to produce a compressed fluid flow CFS.

[0347] Compressors are typically positive displacement compressors or power compressors. Positive displacement compressors include reciprocating compressors that use a piston driven by a crankshaft to deliver fluid at higher pressure. Reciprocating compressors can be single-stage or multi-stage. Positive displacement compressors also include rotary screw compressors, conical screw compressors, rotary vane compressors, rolling piston compressors, or scroll compressors.

[0348] The compressor may also be a powered compressor, such as a centrifugal compressor or an axial flow compressor.

[0349] Preferably, the compressor is a rotary screw compressor, a centrifugal compressor, a piston compressor, or an axial flow compressor.

[0350] After compression in the compressor or after each compression step, it is preferable to pass the fluid flow CFS through one or more heat exchangers to dissipate heat from the compressed fluid or to utilize the heat of compression as a heat source for heating other processes or steps in the gas processing process.

[0351] Alternatively, compression may be supplemented by one or more additional cooling steps to liquefy the CO2. The CO2 can be cooled in a heat exchanger, which is an evaporator for a heat transfer material, preferably liquid ammonia. The evaporated heat transfer material is then compressed, cooled, and expanded in a conventional cooling circuit. Two or more cooling circuits can also be combined in series, thereby reducing the energy consumption for cooling.

[0352] Furthermore, the CO2 may be compressed and cooled by external water, expanded to transport temperature, and then compressed. Non-liquefied CO2 is preferably separated and recycled in the compression process. Energy consumption can be reduced by carrying out compression and depressurization (evaporation) in several steps.

[0353] Drying and other purification processes Generally, it is preferable to dry the CO2-containing flow GS. Drying can be performed before, after, or after one or more of the compression or cooling steps.

[0354] Drying is preferably carried out in the form of pressure fluctuation adsorption (PSA), more preferably in the form of temperature swing adsorption (TSA), or in the form of a glycol drying operation.

[0355] PSA or TSA can be performed by methods well known to those skilled in the art. Different standard procedures are described, for example, in Nag, Ashis, “Distillation and Hydrocarbon Processing Practices”, PennWell 2016, ISBN 978-1-59370-343-1, or in A. Terrigeol, GPA Europe, Annual Conference, Berlin, Germany, 23rd-25th May, 2012 (https: / / www.cecachemicals.com / export / sites / ceca / .content / medias / downloads / products / dtm / molecular-sieves-contaminants-effects-consequences-and-mitigation.pdf).

[0356] In PSA or TSA, it is preferable to use zeolite, activated carbon, or molecular sieves.

[0357] In PSA or TSA, it is preferable to use molecular sieves as solid adsorbents.

[0358] In glycol drying operations, it is preferable to use liquid absorbents such as monoethylene glycol (MEG), diethylene glycol (DEG), triethylene glycol (TEG), or tetraethylene glycol (TREG). TEG is particularly preferred as the liquid absorbent.

[0359] Glycol drying operations can be carried out by process modifications well known to those skilled in the art. For examples of glycol drying, see, for example, Nag, Ashis, “Distillation and Hydrocarbon Processing Practices”, PennWell 2016, ISBN 978-1-59370-343-1.

[0360] Similarly, other components such as carbonyl sulfide (COS) and hydrogen sulfide may be removed by installing additional filters and adsorbents.

[0361] Transportation, storage, and utilization: The fluid-flow CFS is preferably transported to its storage location or its final use. CO2 can be transported via pipelines or by carriers such as trucks, trains, and ships.

[0362] Suitable storage sites are depleted oil and gas reservoirs, mines and saltwater aquifers, or suitable geological structures such as rock formations.

[0363] CO2 can also be used by the food industry, the petroleum industry, and the chemical industry.

[0364] A preferred use of CO2 in the food industry is the carbonation of beverages.

[0365] Other uses of recovered carbon dioxide include enhancing petroleum recovery, or converting it into fuel, cement, minerals, or chemicals, or using it as a material for fire extinguishers, a solvent, an inert gas, or a refrigerant.

[0366] Recycling process d): According to the present invention, the regenerated absorbent A3 obtained at the bottom of the regenerator from step c) is returned to the absorption step b).

[0367] The recycled absorbent material is preferably recycled to one of the supply points for absorbers designed for recycled absorbent material, as described above.

[0368] overview: The method of the present invention enables the utilization of thermal energy inherent in the heat flow HS1, particularly the fluid flow FS1, to provide energy for the energy-intensive regeneration process c).

[0369] The use of two heat pumps connected in series has the advantage that the thermal energy from the heat flow HS1, particularly FS1, can be increased to a level in heat pump HP2 that allows for the generation of steam, which can then be used to transfer heat to the regeneration process c). Thus, the flow generated in heat pump HP2 can effectively replace the process steam that is normally required as a heat source in the regeneration process c). Therefore, the use of two heat pumps connected in series can generate process steam by replacing the need to install a separate process steam production process at the location of the acid gas removal unit, or the need for a steam turbine such as a back pressure turbine or extraction condensate turbine. Thus, the present invention is particularly useful when process steam is not readily available at the location of the acid gas removal unit. However, where process steam is readily available, the method according to the present invention may also be useful as an alternative method for generating process steam, as it allows for the use of potentially limited process steam resources for other purposes, or reduces power losses in the power plant associated with process steam production. In addition, the method according to the present invention is an interesting alternative in the design of a new power plant coupled with an acid gas removal unit for carbon capture. This is because it reduces the need to divert energy used for steam production to power the recycling process. In addition, the method of the present invention is a useful method for electrifying steam production so that the steam required for the amine gas treatment process can be supplied by "green" electricity from renewable resources.

[0370] In a preferred embodiment of the present invention, thermal energy from a gaseous heat flow HS1, particularly a fluid flow FS1, is transferred to a regeneration process via an intermediate cooling loop including a direct-contact cooler DCC and a coolant CM. Direct heat exchange has the advantage of increasing the exchange area between the two fluid flows HS1 and CMS1, reducing thermal resistance, and maximizing thermal efficiency. In addition, direct heat exchangers typically have lower operating and capital costs than indirect heat exchangers because they have a high heat transfer coefficient per unit volume and fouling and corrosion are usually not a problem. Furthermore, because direct heat exchangers have a lower pressure drop compared to indirect heat exchangers, expensive equipment such as blowers or fans required to transport fluid flows FS1 and FS2 in indirect gas-liquid heat exchangers can be reduced or even eliminated in direct heat exchangers.

[0371] The method of the present invention is - When water is used as the cooling medium in the cooling medium flow CMS1 and cooling medium flow CMS2, - When using ammonia, butane, or R1233zd(e) as the heat transfer material HTM1, - When using water as the heat transfer material HTM2, It is particularly efficient.

[0372] When using this combination of cooling material and heat transfer material, a particularly high coefficient of performance (COMS) can be achieved for the heat pump.

[0373] In a preferred embodiment of the present invention, the method of the present invention can be combined with an additional heat pump designed to transfer thermal energy from other heat sources present in the gas processing process.

[0374] Other such heat sources include, but are not limited to, the heat source HS described above. - In an intercooler, or by incorporating a heat exchanger into the absorber, the absorbed heat generated within the absorber can be utilized. - If the rewashing zone is equipped with a pump and cooler, the heat absorbed in the rewashing zone located above the absorber, - The heat of condensation of condensates at the top of the absorber or regenerator, - Compression heat generated when the gas flow GS is compressed into a supercritical fluid during the compression process. This includes, but is not limited to, these.

[0375] By using these additional measures, the energy requirements for carbon capture and storage can be further reduced, and as a result, the diversion of electricity from power plants to gas processing units can be reduced.

[0376] Second aspect - Apparatus for producing deoxidized fluid flow In a second aspect, the present invention relates to an apparatus for deoxidizing a fluid flow. [Brief explanation of the drawing]

[0377] [Figure 1] This shows an apparatus for deoxidizing a fluid flow useful for carrying out the process according to Embodiment A of the present invention. [Figure 2] This shows an apparatus for deoxidizing a fluid flow useful for carrying out the process according to Embodiment B of the present invention. [Figure 3] This shows an apparatus useful for carrying out the process according to Embodiment C of the present invention, which involves direct heat transfer in step i). [Figure 4] This shows an apparatus useful for carrying out the process of the present invention according to Embodiment C, which involves indirect heat transfer in step i). [Modes for carrying out the invention]

[0378] Figure 1 shows an apparatus for deoxidizing a fluid flow useful for carrying out the process according to Embodiment A of the present invention, and the apparatus is a) A direct contact cooler, a. The inlet of the fluid flow FS1, b. Outlet of fluid flow FS2, c. The inlet of the cooling medium flow CMS1, d. Outlet of the cooling medium flow CMS2, Including a direct contact type cooler, b) an absorber, a. The inlet of the fluid flow FS2, b. The outlet of the deoxidized fluid flow FS3, c. Inlet of absorbent flow A1, d. Inlet for recycled absorbent flow A3, e. Outlet of loaded absorbent flow A2, An absorber having, c) A regenerator, a. The inlet of the loaded absorbent flow A2, b. Outlet of recycled absorbent stream A3 and / or AS1, c. The inlet of the absorbent flow AS2, d. The outlet of the acidic gas flow GS, A regenerator having, d) Heat pump HP1, a. Heat exchanger HE1, i. The inlet of the heat transfer material flow HTMS1, ii. The outlet of the heat transfer material flow HTMS2, A heat exchanger HE1 has, b. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow HTMS2, and the last compressor in series has an outlet for a heat transfer material flow HTMS3, c. Heat exchanger HE-R, i. The inlet of the heat transfer material flow HTMS3, ii. The outlet of the heat transfer material flow HTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, This includes the heat exchanger HE-R, This includes the HP1 heat pump, Includes.

[0379] Figure 2 shows an apparatus for deoxidizing a fluid flow useful for carrying out the process according to Embodiment B of the present invention, and the apparatus is e) Heat pump HP2, a. Heat exchanger HE2, i. The inlet of the heat transfer material flow SHTMS1, ii. The outlet of the heat transfer material flow SHTMS2, iii. The inlet of the heat transfer material flow HTMS3, iv. The outlet of the heat transfer material flow HTMS4, A heat exchanger HE2 has, b. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow SHTMS2, and the last compressor in series has an outlet for a heat transfer material flow SHTMS3, c. A heat exchanger HE-R that replaces the heat exchanger HE-R described in claim 16, i. The inlet of the heat transfer material flow SHTMS3, ii. The outlet of the heat transfer material flow SHTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, This includes the heat exchanger HE-R, Includes, and further includes, the HP2 heat pump.

[0380] Figure 3 shows an apparatus useful for carrying out the process according to Embodiment C of the present invention, which involves direct heat transfer in step i), and the apparatus is a) an absorber, a. The inlet of the fluid flow FS2, b. The outlet of the deoxidized fluid flow FS3, c. Inlet of absorbent flow A1, d. Inlet for recycled absorbent flow A3, e. Outlet of loaded absorbent flow A2, An absorber having, b) A regenerator, a. The inlet of the loaded absorbent flow A2, b. Outlet of recycled absorbent stream A3 and / or AS1, c. The inlet of the absorbent flow AS2, d. The outlet of the acidic gas flow GS, A regenerator having, c) Heat pump HP1, a. A heat exchanger HE1 which is a direct contact type cooler, i. The inlet of the heat transfer material flow HTMS1, ii. The outlet of the heat transfer material flow HTMS2a, A heat exchanger HE1 is a direct contact type cooler, and b. One or more evaporation means for expanding the heat transfer material HTMS2a, i. The inlet of the heat transfer material flow HTMS2a, ii. Outlet of heat transfer material flow HTMS2b(g) and Having one or more evaporation means, c. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow HTMS2b(g), and the last compressor in series has an outlet for a heat transfer material flow HTMS3, d. Heat exchanger HE-R, i. The inlet of the heat transfer material flow HTMS3, ii. The outlet of the heat transfer material flow HTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, This includes the heat exchanger HE-R, This includes the HP1 heat pump, Includes.

[0381] Figure 4 shows an apparatus useful for carrying out the process of the present invention according to Embodiment C, which involves indirect heat transfer in step i), and the apparatus is a) A direct contact cooler, a. The inlet of the fluid flow FS1, b. Outlet of fluid flow FS2, c. The inlet of the cooling medium flow CMS1, d. Outlet of the cooling medium flow CMS2, Including a direct contact type cooler, b) an absorber, a. The inlet of the fluid flow FS2, b. The outlet of the deoxidized fluid flow FS3, c. Inlet of absorbent flow A1, d. Inlet for recycled absorbent flow A3, e. Outlet of loaded absorbent flow A2, An absorber having, c) A regenerator, a. The inlet of the loaded absorbent flow A2, b. Outlet of recycled absorbent stream A3 and / or AS1, c. The inlet of the absorbent flow AS2, d. The outlet of the acidic gas flow GS, A regenerator having, d) Heat pump HP1, a. Heat exchanger HE1, i. The inlet of the heat transfer material flow HTMS1, ii. The outlet of the heat transfer material flow HTMS2a, A heat exchanger HE1 has, b. One or more evaporation means for expanding the heat transfer material HTMS2a, i. The inlet of the heat transfer material flow HTMS2a, ii. Outlet of heat transfer material flow HTMS2b(g) and Having one or more evaporation means, c. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow HTMS2b(g), and the last compressor in series has an outlet for a heat transfer material flow HTMS3, d. Heat exchanger HE-R, i. The inlet of the heat transfer material flow HTMS3, ii. The outlet of the heat transfer material flow HTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, This includes the heat exchanger HE-R, This includes the HP1 heat pump, Includes.

[0382] In all diagrams, the absorber is configured as an absorption column.

[0383] The absorption column preferably has an absorption zone. In the context of the present invention, the absorption zone is considered to be a section of the absorption column where the fluid flow makes mass transfer contact with the absorbent. To improve contact and provide a large mass transfer interface, the absorption zone preferably includes an internal structure, preferably random packing, structured packing, and / or a tray.

[0384] In a column having random or structured packing, the absorption zones are preferably divided into 2 to 4 packing compartments that are stacked on top of each other and separated from each other by support and retention trays and / or distribution trays.

[0385] If the absorption zone includes random or structured fillers, the height of the structured / random fillers in the absorption zone is preferably in the range of 5 to 20 m, more preferably in the range of 6 to 15 m, and most preferably in the range of 8 to 14 m.

[0386] If the absorption zone includes trays, the number of trays in the absorption zone is preferably in the range of 8 to 30, more preferably 12 to 25, and most preferably 15 to 23.

[0387] Preferably, the inlet for the fluid flow FS2 to be deoxidized is located below or within the lower region of the absorption zone.

[0388] Fresh absorbent A1 may be supplied through an inlet located above or in the upper region of the absorption zone. Supply of fresh absorbent may also include supplying individual components of the absorbent, such as supplemental water.

[0389] Regenerated absorbent A3 may be supplied through the same inlet or similarly through an inlet in the upper region of the absorption zone or above the absorption zone.

[0390] Preferably above the absorption zone, and preferably at the top of the absorption column, there is an outlet for the deoxidized fluid stream FS3.

[0391] It is preferable that a demister (not shown) is installed within the region of the extraction point for the deoxidized fluid flow.

[0392] In a particularly preferred embodiment, the supply point for the detergent is located in the upper region of the absorption zone or above the absorption zone (not shown).

[0393] In very specific embodiments, the absorber includes an additional rewashing zone above the absorption zone (not shown). The rewashing zone is generally configured as a compartment of the absorber in the form of a rectification compartment located above the supply point for the absorbent. The rewashing zone preferably has random packing, structured packing, and / or trays to enhance contact between the fluid flow and the washing liquid. The rewashing zone particularly has trays, especially valve trays, bubble cap trays, Souman trays, or sieve trays.

[0394] Preferably, a supply point for the cleaning agent (not shown) is located above the rewashing zone. The rewashing zone preferably includes 1 to 7 trays, more preferably 2 to 6, most preferably 3 to 5 trays, or a packing height (random packing or structured packing) of preferably 1 to 6 m, more preferably 2 to 5, most preferably 2 to 3 m.

[0395] A collection tray (not shown) may be located below the rewashing zone and can collect and recycle the cleaning fluid. Recycling is generally affected here by a pump (not shown) that pressurizes the cleaning fluid from the collection tray to a supply point. In the case of recycling, the cleaning fluid may be cooled by a heat exchanger (not shown).

[0396] Preferably, the lower region of the absorber has a liquid extraction section for the loaded absorbent A2.

[0397] In a preferred embodiment, a heat exchanger HE-CF is located between the liquid extraction section of the loaded absorbent in the absorber and the supply section of the loaded absorbent in the regenerator. The heat transfer medium used in this heat exchanger is preferably the recycled flow of regenerated absorbent A3 from the bottom of the regenerator to the absorber. In this preferred embodiment, the overall energy demand of the process can be reduced.

[0398] The heat exchanger HE-CF can be configured as a plate heat exchanger or a shell-and-tube heat exchanger. The heat transfer medium used in the heat exchanger is preferably a bottom flow from a regenerator.

[0399] In the diagram, it is preferable that the outlet of the loaded absorbent A2 from the absorber is connected to the regenerator via a pipeline and a heat exchanger.

[0400] The regenerators in all figures preferably include a regeneration zone, an evaporator, a supply inlet for the loaded absorbent A2, a liquid extraction section (outlet) at the bottom of the regenerator for the absorbent A3 to be at least partially regenerated, a rewashing zone (not shown), and an outlet for extracting the acidic gas flow GS from the top region of the regenerator.

[0401] In this context, the regeneration zone is considered to be the area of ​​the regenerator where the loaded absorbent comes into contact with the steam produced by the reboiler.

[0402] To improve contact and provide a large mass transfer interface, the regeneration zone preferably includes an internal structure, preferably random packing, structured packing, and / or a tray.

[0403] In a column having random or structured packing, the regeneration zone is preferably divided into 2 to 4 packing compartments that are stacked on top of each other and separated from each other by support and retention trays and / or distribution trays.

[0404] If the regeneration zone includes random fillers or structured fillers, the height of the random fillers / structured fillers in the regeneration zone is preferably in the range of 5 to 15 m, more preferably in the range of 6 to 12 m, and most preferably in the range of 8 to 12 m.

[0405] If the regeneration zone includes trays, the number of trays in the regeneration zone is preferably in the range of 10 to 30, more preferably 15 to 25, and most preferably 17 to 23.

[0406] The supply inlet for the loaded absorbent A2 is preferably above or located in the upper region of the regeneration zone.

[0407] The regenerators in Figures 1 and 2 further include a reboiler HE-R.

[0408] The reboiler is preferably a kettle-type reboiler, a natural circulation evaporator, or a forced circulation evaporator.

[0409] The reboiler HE-R is preferably connected via a pipeline to the liquid extraction section at the bottom of the regenerator in order to introduce the absorbent flow AS1 into the reboiler HE-R. The bottom generally refers to the area below the regeneration zone.

[0410] Typically, the absorbent flow AS2, which is a vapor-liquid mixture generated in the reboiler, is preferably introduced into the lower region of the regenerator through a supply point that is above the liquid extraction section at the bottom but below the regeneration zone.

[0411] In a further preferred embodiment, the bottom of the regenerator is divided by a collection tray (not shown). The absorbent collected in the collection tray is supplied to a cross-flow heat exchanger HE-CF. The flow AS2 is preferably recycled to the regenerator located below the collection tray.

[0412] In all figures, the regenerator preferably includes an extraction point for the gas flow GS formed during regeneration. The extraction point for the gas flow GS formed during regeneration is preferably located in the top region of the regenerator. A demister (not shown) is preferably located in the extraction point region.

[0413] The regenerator in the figure preferably includes a rewashing zone (not shown) having an internal structure. The internal structure present in the rewashing zone is preferably structured packing or random packing, and the packing height (random packing / structured packing) is preferably in the range of 1 to 10 m, more preferably 2 to 8 m, and most preferably 3 to 6 m. Alternatively, the internal structure present in the rewashing zone is a tray. More specifically, the number of trays is preferably in the range of 3 to 20, more preferably 4 to 16, and preferably 6 to 12. The trays in the washing section may be, for example, valve trays, bubble cap trays, Souman trays, or sieve trays.

[0414] In the diagram, a separate supply of cleaning fluid may be located above or within the upper region of the rewashing zone (not shown). If additional cleaning fluid, such as fresh water, is supplied, it is preferable to guide this cleaning fluid into the regenerator together with the condensate from an additional condensation process at the top of the regenerator. Preferably, the extraction point of the gas flow GS formed in the regenerator is connected to a top condenser (not shown). The top condenser preferably includes a heat exchanger, a phase separation vessel (phase separation vessel), a gas extraction section, and a condensate outlet. The condenser used may be, for example, a cooling coil or helical tube, a jacketed tube condenser, and a shell-and-tube heat exchanger condenser.

[0415] The present invention will be explained by the following examples. [Examples]

[0416] Example 1 is based on calculations performed using a process simulation model. The phase equilibrium of the carbon recovery portion was described using (KSPitzer, Activity Coefficients in Electrolyte Solutions 2nd ed., CRC Press, 1991, Chapter 3, Ion Interaction Approach: Theory). The absorption process simulation was described by a mass transfer-based approach, the details of which are described in Asprion (Asprion, N.: Nonequilibrium Rate Based Simulation of Reactive Systems: Simulation Model, Heat Transfer, and Influence of Film Discretization, Ind.Eng.Chem.Res. (2006) 45(6), 2054-2069).

[0417] Regarding heat pumps, the necessary thermodynamic data is provided by PC SAFT(NH3) (Gross, J.; Sadowksi, G.: Industrial & Engineering Chemistry Research, 2002, 41(22)5510), and regarding water, the NBS tables (NBS / NCR Steam Tables by L. Haar, et al., New York: Hemisphere Publishing, 1984) are provided.

[0418] Example 2 is based on calculations using a further simulation tool called EBSILON® Professional (www.ebsilon.com), which utilizes the thermodynamic package REFPROP (https: / / refprop-docs.readthedocs.io / en / latest / DLL / index.html). This tool is typically applied to simulations of power plants, but is generally applicable to any type of thermodynamic cycle.

[0419] Example 1: Using the cooling medium flow CMS2 from a direct contact cooler (DCC) as the heat flow HS1 of a serial heat pump. Example 1 is based on the process scheme shown in Figure 2, which includes a direct-contact cooler and two series-connected heat pumps HP1 and HP2, with heat pump HP2 configured as an open-loop heat pump, with some modifications as further described below.

[0420] A fluid flow FS1 with the composition shown in Table A below, a temperature of 70°C, and a pressure of 1.01 bar, at a rate of 1389 t / h, is supplied to the bottom of a heat exchanger HE-C configured as a direct contact cooler (DCC). In HE-C, FS1 is brought into contact with water, which is a cooling medium flow CMS1, in a counterflow manner to obtain a fluid flow FS2 with a flow rate of 124.1 t / h, a temperature of 35°C, and a pressure of 0.99 bar. The fluid flow FS2 is slightly compressed to a pressure of 1.07 bar and a temperature of 43.4°C before being introduced into absorption step b). CMS1 is introduced to the top of HE-C at a flow rate of 3233.3 t / h, a temperature of 40°C, and a pressure of 2.25 bar. Thermal energy is transferred from the fluid flow FS1 to the cooling medium flow CMS1, obtaining the cooling medium flow CMS2 at the bottom of HE-C. A small portion of CMS2 (150.7 t / h) is purged from the process. A 3275 t / h CMS2 with a temperature of 61.4°C and a pressure of 1.01 bar is used as the heat flow HS1 for a serial heat pump that includes a first heat pump HP1 with ammonia as the heat transfer material HTM1 and a second heat pump HP2 with water as the heat transfer material HTM2. Heat pump HP1 is designed as a closed-loop heat pump including a regeneration process. Heat pump HP2 is designed as an open-loop heat pump. The thermal energy (CMS2) from the heat flow HS1 is transferred through the evaporator HE1 of heat pump HP1 to a heat transfer material flow HTMS1 with a flow rate of 408.19 t / h, a temperature of 37.7°C and a pressure of 14.54 bar, resulting in a gaseous heat transfer material flow HTMS2 with a flow rate of 408.19 t / h, a temperature of 37.6°C and a pressure of 14.49 bar. Furthermore, the cooled refrigerant flow CMS3 is further cooled to a temperature of 32°C in an additional cooler and pumped to the heat exchanger HE-C at a pressure of 4.5 bar. The heat transfer material flow HTMS2 is compressed in a compressor to obtain a heat transfer material flow HTMS3 at a pressure of 75.48 bar and a temperature of 197.6°C. The heat transfer material flow HTMS3 is supplied to the heat exchanger HE2, which is the condenser of heat pump HP1 and the evaporator of heat pump HP2, to obtain a cooled liquid heat transfer material flow HTMS4 at a temperature of 109.6°C and a pressure of 75.43 bar.To close the loop and recycle the heat transfer material flow HTMS4 to the heat exchanger HE1, the heat transfer material flow HTMS4 is expanded to obtain a cooled heat transfer material flow HTMS5 having a temperature of 37.7°C and a pressure of 14.54 bar. The cooled heat transfer material flow HTMS5 is partially liquid (246.8 t / h) and gaseous (161.4 t / h) and is recycled as heat transfer material flow HTMS1 to the heat exchanger HE1. In the heat exchanger HE2, thermal energy is transferred from the heat transfer material flow HTMS3 to a second heat transfer material flow SHTMS1 having a flow rate of 174.3 t / h, a temperature of 99.6°C, and a pressure of 5 bar, to obtain a second heat transfer material flow SHTMS2 having a flow rate of 174.3 t / h, a pressure of 1 bar, and a temperature of 99.6°C. The second heat transfer material flow SHTMS2 is compressed in three stages, each stage containing one compressor. In the first compressor, the pressure is increased to 1.5 bar and the temperature to 146.1°C. After the first compressor, an additional flow of water with a flow rate of 3.8 t / h, a temperature of 99.6°C, and a pressure of 5 bar is added to obtain a second heat transfer material flow SHTSM3* with a temperature of 121.4°C, a pressure of 1.5 bar, and a flow rate of 178.1 t / h. In the second compressor, the second heat transfer material flow STMS3* is further compressed to a pressure of 2.3 bar and a temperature of 134.1°C. Another flow of water with a temperature of 99.6°C and a pressure of 5 bar is added at a flow rate of 5.8 t / h to obtain a second heat transfer material flow SHTM3** with a temperature of 134.1°C, a pressure of 2.3 bar, and a flow rate of 183.9 t / h. In the third compressor, the second heat transfer material flow SHTMS** is further compressed to obtain a second heat transfer material flow SHTMS*** with a pressure of 3.4 bar and a temperature of 184.3°C. A further flow of water having a temperature of 99.6°C, a pressure of 5 bar and a flow rate of 6.1 t / h is added to the second heat transfer material flow SHTMS*** to obtain a second heat transfer material flow SHTMS3 having a temperature of 147.8°C, a pressure of 3.4 bar and a flow rate of 190.0 t / h. The thermal energy from the second heat transfer material flow SHTMS3 is transferred to the absorber's reboiler to maintain a temperature of 127.3°C at the bottom of the absorber. A lower temperature second heat transfer material flow SHTMS4 is obtained, having a temperature of 137.3°C and a pressure of 3.34 bar.

[0421] The coefficient of performance (COP), an indicator of the performance of a heat pump system, is 2.34.

[0422] The heat pump HP2 was operated as an open-loop heat pump, meaning the second heat transfer material flow SHTMS4 was not recycled to the heat exchanger HE2. Alternatively, the heat pump HP2 could be operated as a closed-loop heat pump, and after adjusting the pressure and temperature through additional expansion, cooling, or compression processes to tune the characteristics of the flow HTMS4 to each input flow, at least a portion of the second heat transfer material flow SHTMS4 could be recycled to the heat exchanger HE2, for example, as flow SHTMS1, or as an additional flow of heat transfer material HTM2 in the compression process.

[0423] This embodiment demonstrates that the regeneration process c) can be heated by effectively utilizing the energy contained in the low-temperature fluid flow FS1.

[0424] To achieve this with conventional heat pumps, it is necessary to find a heat transfer material that can undergo a phase transition at the temperature and pressure of the heat exchanger HE1, compress it, and obtain the high temperature required in the regeneration process c), especially in the reboiler. Ammonia is not suitable because it needs to be compressed to a supercritical pressure in the heat exchanger HE2.

[0425] In Example 1, only the amount of steam required in regeneration step c) is produced. Since the process of the present invention produces steam, it can be supplemented by other steam sources, or excess steam can be provided to other consumers. Alternatively, excess steam can be released into the environment.

[0426] [Table 1]

[0427] Example 2: Example 2 is based on the process scheme shown in Figure 4, which includes a combination of a direct-contact cooler and a modified heat pump, with several modifications as described below.

[0428] In a direct-contact cooler (DCC or HE-C), heat is transferred from the fluid gas flow FS2 to the cooling medium flow CMS1, resulting in a cooling medium flow CMS2 with a pressure of 1.2 bar and a temperature of 62°C at a flow rate of 5500 t / h. The cooling medium flow CMS2 is supplied to the heat exchanger HE1 of the modified heat pump HP1 to obtain a cooled cooling medium flow CMS3 with a temperature of 50°C and a pressure of 1.2 bar. The flow CMS3 is further cooled in a water cooler to obtain a cooling medium flow CMS4 with a temperature of 42°C, which is recycled to the direct-contact cooler as the cooling medium flow CMS1. In the heat exchanger HE1, heat is transferred from the cooling medium flow CMS1 to a heat transfer material flow HTMS1 with a flow rate of 5500 t / h, a pressure of 1.2 bar, and a temperature of 46°C, resulting in a heat transfer material flow HTMS2 with a temperature of 57°C and a pressure of 1.15 bar. The heat transfer material flows HTMS1 and HTMS2a are flows of the heat transfer material HTM1, which is water. The heat transfer material flow HTMS2a is expanded at a pressure of 0.1 bar to obtain the heat transfer material flow HTMS2b, which has a temperature of 46°C and a pressure of 0.1 bar. The heat transfer material flow HTMS2b consists of a liquid flow HTMS2a(l) with a flow rate of 5500 t / h and a gaseous flow HTMS2a(g) with a flow rate of 113.6 t / h. After the liquid heat transfer material flow HTMS2b(l) is compressed to a pressure of 1.2 bar, it is recycled to the heat exchanger HE1 as the heat transfer material flow HTMS1, obtaining a heat transfer material flow with a flow rate of 5500 t / h, a pressure of 1.2 bar, and a temperature of 45.8°C. The gaseous heat transfer material flow HTMS2b(g) is supplied to the compression process. Prior to expansion, an additional flow of heat transfer material HTM1 is added to the heat transfer material flow HTMS2a at a flow rate of 1.15 bar, a temperature of 75°C, and a flow rate of 113.6 t / h to compensate for the gaseous portion of the heat transfer material flow HTMS2b supplied to the compression process and maintain the mass balance of the recycling loop with the liquid flow HTMS1 and the liquid flow HTMS2a.

[0429] The compression process for obtaining the heat transfer mass flow HTMS3 includes five compression stages, each stage including a compressor.

[0430] As described above, the gaseous portion of the heat transfer material flow HTMS2b with a flow rate of 113.6 t / h, a temperature of 45.8°C, and a pressure of 0.1 bar is supplied to the first compression stage to obtain a heat transfer material flow HTMS3* with a pressure of 0.2 bar and a temperature of 114.61°C. Before supplying flow HTMS3* to the second compression stage, an additional flow of heat transfer material HTM1 with a temperature of 75°C and a pressure of 5 bar is added to flow HTMS3* with a flow rate of 3.7 t / h to obtain a heat transfer material flow HTMS3* with a flow rate of 117.3 t / h, a pressure of 0.2 bar, and a temperature of 75°C.

[0431] The heat transfer material flow HTMS3* is supplied to the second compression stage to obtain a heat transfer material flow HTMS3** with a pressure of 0.4 bar and a temperature of 149.6°C. Before supplying the flow HTMS3** to the third compression stage, an additional flow of heat transfer material HTM1 with a temperature of 75°C and a pressure of 5 bar is added to the flow HTMS3** at a flow rate of 6.3 t / h to obtain a heat transfer material flow HTMS3** with a flow rate of 123.62 t / h, a pressure of 0.4 bar, and a temperature of 85°C.

[0432] The heat transfer material flow HTMS3** is supplied to the third compression stage to obtain a heat transfer material flow HTMS3*** with a pressure of 0.8 bar and a temperature of 161.1°C. Before supplying the flow HTMS3*** to the fourth compression stage, an additional flow of heat transfer material HTM1 with a temperature of 75°C and a pressure of 5 bar is added to the flow HTMS3** at a flow rate of 6.0 t / h to obtain a heat transfer material flow HTMS3*** with a flow rate of 129.6 t / h, a pressure of 0.8 bar, and a temperature of 103°C.

[0433] The heat transfer material flow HTMS3*** is supplied to the fourth compression stage to obtain a heat transfer material flow HTMS3**** with a pressure of 1.6 bar and a temperature of 182.1°C. Before supplying the flow HTMS3**** to the fifth and final compression stages, an additional flow of heat transfer material HTM1 with a temperature of 75°C and a pressure of 5 bar is added to the flow HTMS3** at a flow rate of 6.5 t / h to obtain a heat transfer material flow HTMS3**** with a flow rate of 136.1 t / h, a pressure of 1.6 bar and a temperature of 123°C.

[0434] The heat transfer material flow HTMS3**** is supplied to the fifth compression stage to obtain a heat transfer material flow HTMS3 with a pressure of 3.2 bar and a temperature of 205.2°C. Before supplying the flow HTMS3 to the heat exchanger HE-R to transfer heat to regeneration step c), an additional flow of heat transfer material HTM1 with a temperature of 75°C and a pressure of 5 bar is added to the flow HTMS3 at a flow rate of 7.4 t / h to obtain a heat transfer material flow HTMS3 with a flow rate of 143.5 t / h, a pressure of 3.2 bar and a temperature of 143°C.

[0435] In order to maintain a temperature of 127°C at the bottom of the regenerator, heat is transferred from the heat transfer material flow HTMS3 to the regeneration process c) in the reboiler of the regenerator.

[0436] The coefficient of performance for the heat pump is 3.57.

[0437] The heat pump operates as an open-loop heat pump without recycling the heat transfer material water to the evaporation process. However, at least a portion of the heat transfer material flow HTMS4 can be recycled to, for example, the evaporation or compression process after the pressure and temperature have been finally adjusted by additional expansion, cooling, or compression processes to match the characteristics of the flow HTMS4 to each input flow such as the heat transfer material flow HTMS1 or the heat transfer material flow HTMS2a.

Claims

1. A method for producing a deoxidized fluid flow from a fluid flow containing at least one acidic gas, a) A heat energy transfer step to transfer thermal energy from a fluid flow FS1 containing at least one type of acidic gas to a regeneration step c) to obtain a fluid flow FS2 having reduced thermal energy compared to the fluid flow FS1, b) An absorption step in which the cooled fluid flow FS2 is brought into contact with the absorbent A1 in the absorber to obtain an absorbent A2 to which an acidic gas and at least partially deoxidized fluid flow are loaded, c) A regeneration step in which at least a portion of the loaded absorbent A2 obtained in step b) is regenerated in a regenerator to obtain at least partially regenerated absorbent A3 and a gas flow GS containing at least one acidic gas, d) A recycling step in which at least the by-flow of the recycled absorbent A3 from step c) is recycled back to the absorption step b), Includes, The heat energy transfer step a) is a method comprising a combination of a direct contact cooler (DCC) and one or more heat pumps.

2. The heat energy transfer step a) is, (i) Transferring thermal energy from the fluid flow FS1 to the cooling material flow CMS1 within a direct contact cooler, and obtaining a fluid flow FS2 having reduced thermal energy compared to the cooling material flow CMS2 and the fluid flow FS1, (ii) To transfer thermal energy from the cooling material flow CMS2 to the heat transfer material flow HTMS1 in the heat exchanger HE1, and to obtain a heat transfer material flow HTMS2 having higher thermal energy than the heat transfer material flow HTMS1, (iii) Compressing the heat transfer material flow HTMS2 in one or more compression steps to obtain a heat transfer material flow HTMS3 having a higher pressure than the heat transfer material flow HTMS2, (iv) Transferring thermal energy from the heat transfer material flow HTMS3 to the regeneration step c) to obtain the heat transfer material flow HTMS4, The method according to claim 1, including the method described in claim 1.

3. The heat energy transfer step a) is, (i) Transferring thermal energy from the fluid flow FS1 to the liquid heat transfer material flow HTMS1 of the heat transfer material HTM1 within a direct contact cooler to obtain the liquid heat transfer material flow HTMS2a, (ii) Expanding the heat transfer medium flow HTMS2a in one or more expansion steps to obtain a gaseous heat transfer material flow HTMS2b(g) having a pressure lower than that of the heat transfer material flow HTMS2a, (iii) Compressing the heat transfer material flow HTMS2b(g) in one or more compression steps to obtain a gaseous heat transfer material flow HTMS3 having a higher pressure than the heat transfer material flow HTMS2b(g), (iv) Transferring thermal energy from the heat transfer material flow HTMS3 to the regeneration step c) to obtain the heat transfer material flow HTMS4, The method according to claim 1, including the method described in claim 1.

4. The method according to any one of claims 2 or 3, comprising an additional recycling step R1) in which the heat transfer material flow HTMS4 obtained in step iv) is recycled to step i) or step (ii).

5. The method according to any one of claims 2 or 3, wherein the heat transfer material flow HTMS4 is not recycled to the heat exchanger HE1.

6. The heat energy transfer process is as follows: i) Transferring thermal energy from the heat flow HS1 to the heat transfer medium flow HTMS1 of the heat transfer material HTM1 within the heat exchanger HE1 of the first heat pump HP1, thereby obtaining a heat transfer medium flow HTMS2 having increased thermal energy compared to the heat transfer medium flow HTMS1, ii) Compressing the heat transfer medium flow HTMS2 within the first heat pump HP1 to obtain a heat transfer medium flow HTMS3 having a higher pressure than the heat transfer medium flow HTMS2, iii) Transferring thermal energy from the heat transfer medium flow HTMS3 of the first heat pump HP1 to the second heat transfer medium flow SHTMS1 of the second heat transfer material HTM2 within the heat exchanger HE2 of the second heat pump HP2, thereby obtaining a second heat transfer medium flow SHTMS2 having increased thermal energy compared to the second heat transfer medium flow SHTMS1, and a heat transfer medium flow HTMS4 having a decreased thermal energy content compared to the heat transfer medium flow HTMS3. iv) Compressing the second heat transfer medium flow SHTMS2 within the second heat pump HP2 to obtain a second heat transfer medium flow SHTMS3 having a higher pressure than the second heat transfer medium flow SHTMS2, v) Transferring thermal energy from the second heat transfer medium flow SHTMS3 of the second heat pump HP2 to the regeneration step c) to obtain a second heat transfer medium flow SHTMS4 having a reduced thermal energy content compared to SHTMS3, The method according to claim 1, including the method described in claim 1.

7. The method according to claim 2, 3, or 6, wherein step iv) of claim 2 or 3 or step v) of claim 6 is performed in a heat exchanger HE-R by transferring thermal energy from the second heat transfer medium flow SHTMS4 to the absorbent flow AS1 drawn from the regenerator in step c), obtaining an absorbent flow AS2 having increased thermal energy compared to the absorbent flow AS1, and supplying AS2 to the regenerator in step c).

8. The method according to claim 7, wherein the heat exchanger HE-R is a reboiler of the regenerator.

9. - An additional recycling step R1) and / or to expand the heat transfer medium flow HTMS4 obtained in step 3) to obtain a heat transfer medium flow HTMS5 having a reduced pressure compared to the heat transfer medium flow HTMS4 and being at least partially recycled back to step 1) as a heat transfer medium flow HTMS1. - The method according to any one of claims 6 to 8, comprising an additional recycling step R2) to expand the second heat transfer medium flow SHTMS4 obtained in step 5) to obtain a second heat transfer medium flow SHTMS5 having a reduced pressure compared to the second heat transfer medium flow SHTMS4 and being at least partially recycled to step 3) as the second heat transfer medium flow SHTMS1, or the method according to any one of claims 6 to 8, wherein the second heat transfer medium flow SHTMS4 is not recycled to the heat exchanger HE2.

10. The method according to any one of claims 6 to 9, wherein the heat transfer material HTM1 is selected from the group consisting of ammonia, butane, and RZ123zd(e), and the second heat transfer material HTM2 is water, or the method according to any one of claims 2 to 5, wherein the heat transfer material flow HTMS1 to 4 is a flow of heat transfer material HTM1, and the heat transfer material HTM1 is selected from the group consisting of ammonia, butane, R1233zd(e), R1224yd(z), air, CO2, water, chlorofluorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, hydrofluoroolefin, hydrochlorofluoroolefin, hydrocarbon, perfluoro(2-methyl-3-pentanone), and mixtures of two or more thereof.

11. a) A direct contact type cooler, a. The inlet of the fluid flow FS1, b. Outlet of fluid flow FS2, c. The inlet of the cooling medium flow CMS1, d. The outlet of the cooling medium flow CMS2, Including a direct contact type cooler, b) An absorber, a. The inlet of the fluid flow FS2, b. The outlet of the deoxidized fluid flow FS3, c. The inlet of the absorbent flow A1, d. The inlet of the recycled absorbent flow A3, e. Outlet of loaded absorbent flow A2, An absorber having, c) A regenerator, a. The inlet of the loaded absorbent flow A2, b. Outlet of recycled absorbent stream A3 and / or AS1, c. The inlet of the absorbent flow AS2, d. The outlet of the acidic gas flow GS, A regenerator having, d) Heat pump HP1, a. Heat exchanger HE1, i. The inlet of the heat transfer material flow HTMS1, ii. The outlet of the heat transfer material flow HTMS2, A heat exchanger HE1 has, b. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow HTMS2, and the last compressor in series has an outlet for a heat transfer material flow HTMS3, c. Heat exchanger HE-R, i. The inlet of the heat transfer material flow HTMS3, ii. The outlet of the heat transfer material flow HTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, This includes the heat exchanger HE-R, This includes the HP1 heat pump, A device including a device.

12. e) Heat pump HP2, a. Heat exchanger HE2, i. The inlet of the heat transfer material flow SHTMS1, ii. The outlet of the heat transfer material flow SHTMS2, iii. The inlet of the heat transfer material flow HTMS3, iv. The outlet of the heat transfer material flow HTMS4, A heat exchanger HE2 has, b. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow SHTMS2, and the last compressor in series has an outlet for a heat transfer material flow SHTMS3, c. A heat exchanger HE-R that replaces the heat exchanger HE-R described in claim 11, i. The inlet of the heat transfer material flow SHTMS3, ii. The outlet of the heat transfer material flow SHTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, Heat exchanger HE-R Heat pump HP2 The apparatus according to claim 11, further comprising:

13. a) An absorber, a. The inlet of the fluid flow FS2, b. The outlet of the deoxidized fluid flow FS3, c. The inlet of the absorbent flow A1, d. The inlet of the recycled absorbent flow A3, e. Outlet of loaded absorbent flow A2, An absorber having, b) A regenerator, a. The inlet of the loaded absorbent flow A2, b. Outlet of recycled absorbent stream A3 and / or AS1, c. The inlet of the absorbent flow AS2, d. The outlet of the acidic gas flow GS, A regenerator having, c) Heat pump HP1, a. Heat exchanger HE1 is a direct contact type cooler, i. The inlet of the heat transfer material flow HTMS1, ii. The outlet of the heat transfer material flow HTMS2a, A heat exchanger HE1 is a direct contact type cooler, and b. One or more evaporation means for expanding the heat transfer material HTMS2a, i. The inlet of the heat transfer material flow HTMS2a, ii. The outlet of the heat transfer material flow HTMS2b, Having one or more evaporation means, c. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow HTMS2b, and the last compressor in series has an outlet for a heat transfer material flow HTMS3, d. Heat exchanger HE-R, i. The inlet of the heat transfer material flow HTMS3, ii. The outlet of the heat transfer material flow HTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, This includes the heat exchanger HE-R, This includes the HP1 heat pump, A device including a device.

14. a) A direct contact type cooler, a. The inlet of the fluid flow FS1, b. Outlet of fluid flow FS2, c. The inlet of the cooling medium flow CMS1, d. The outlet of the cooling medium flow CMS2, Including a direct contact type cooler, b) An absorber, a. The inlet of the fluid flow FS2, b. The outlet of the deoxidized fluid flow FS3, c. The inlet of the absorbent flow A1, d. The inlet of the recycled absorbent flow A3, e. Outlet of loaded absorbent flow A2, An absorber having, c) A regenerator, a. The inlet of the loaded absorbent flow A2, b. Outlet of recycled absorbent stream A3 and / or AS1, c. The inlet of the absorbent flow AS2, d. The outlet of the acidic gas flow GS, A regenerator having, d) Heat pump HP1, a. Heat exchanger HE1, i. The inlet of the heat transfer material flow HTMS1, ii. The outlet of the heat transfer material flow HTMS2a, A heat exchanger HE1 has, b. One or more evaporation means for expanding the heat transfer material HTMS2a, i. The inlet of the heat transfer material flow HTMS2a, ii. The outlet of the heat transfer material flow HTMS2b, Having one or more evaporation means, c. One or more compressors in series, wherein the first compressor in series has an inlet for a heat transfer material flow HTMS2b, and the last compressor in series has an outlet for a heat transfer material flow HTMS3, d. Heat exchanger HE-R, i. The inlet of the heat transfer material flow HTMS3, ii. The outlet of the heat transfer material flow HTMS4, iii. The second inlet of the absorbent flow AS1, iv. The second outlet of the absorbent flow AS2, This includes the heat exchanger HE-R, This includes the HP1 heat pump, A device including a device.

15. The fluid flow containing at least one acidic gas is CO ２ The method according to any one of claims 1 to 10, wherein the exhaust gas contains, and the absorbent comprises at least one amine and water.

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