Process for separating carbon dioxide product flow from flue gas flow

Abstract

A process for separating a carbon dioxide product flow from a flue gas flow is disclosed. This process involves passing a flow of carbon dioxide and oxygen through a regenerator to generate a catalyst flow, producing a flue gas flow containing carbon oxides and / or nitrogen oxides, catalyst fines, oxygen, and water. Heat is transferred from the flue gas flow to the water flow in a heat recovery unit, forming a cooled flue gas flow and a steam flow. Water is removed from the cooled flue gas flow in a dewatering unit to provide a dewatered flue gas flow. The dewatered flue gas flow is separated into an oxygen flow and a carbon dioxide product flow.

Description

[[Technical Field]]

[0001] The present technical field relates to a process and an apparatus for regenerating a catalyst from a fluid catalytic process. In particular, the field relates to a process for regenerating a catalyst from a fluid catalytic process using a carbon dioxide recycle stream. [[Background Art]]

[0002] Catalytic cracking can produce various products from larger hydrocarbons. A feedstock of heavy hydrocarbons such as vacuum gas oil is often supplied to a catalytic cracking reactor such as a fluid catalytic cracking reactor. Various products including gasoline products and / or light products such as propene and / or ethene can be produced from such a system.

[0003] Fluid catalytic cracking (FCC) is a hydrocarbon conversion process achieved by contacting hydrocarbons with a catalyst consisting of finely divided particulate matter in a fluid reaction zone. In contrast to hydrocracking, the reaction in catalytic cracking is carried out without substantial added hydrogen or without consumption of hydrogen. As the cracking reaction proceeds, a substantial amount of high carbonaceous material called coke deposits on the catalyst. A high-temperature regeneration operation in a regeneration zone burns the coke from the catalyst. The coke-containing catalyst, referred to herein as coked catalyst, is continuously removed from the reaction zone and replaced by essentially coke-free catalyst from the regeneration zone. Fluidization of catalyst particles by various gas streams facilitates transport of the catalyst between the reaction zone and the regeneration zone. Spent catalyst from the reaction zone can be fully or partially regenerated in the regeneration zone.

[0004] The common objective of these configurations is to maximize the product yield from the reactor while minimizing operating and equipment costs. Optimizing the raw material conversion rate usually requires essentially complete removal of coke from the catalyst. This essentially complete removal of coke from the catalyst is often called complete regeneration. Complete regeneration produces a catalyst with less than 0.1% by weight, preferably less than 0.05% by weight, of coke. To obtain complete regeneration, the catalyst must be exposed to oxygen at a high temperature for a residence time sufficient to allow complete combustion.

[0005] Conventional regenerators typically include a container having a coke catalyst inlet, a regenerated catalyst outlet, and a combustion gas distributor for supplying air or other oxygen-containing gas to the catalyst bed present in the container. A cyclone separator removes the catalyst that has been entrained into the flue gas before the flue gas leaves the regenerator.

[0006] Alternative processes are also used in the production of light olefins. In one approach, hydrocarbon oxygenates, more specifically methanol or dimethyl ether, are used as alternative feedstocks for producing light olefin products. Once the oxygenates are formed, this process involves catalytically converting the oxygenates, such as methanol, into the desired light olefin product in a methanol-to-olefin (MTO) process. In the MTO process, carbonaceous material, i.e., coke, is deposited on the catalyst as the catalyst moves through the reaction zone. The carbonaceous material is removed from the catalyst by oxidative regeneration in one or more regeneration zones, and the catalyst particles removed from the reaction zone are contacted with an oxygen-containing gas stream at a temperature and oxygen concentration sufficient to allow a desired amount of carbonaceous material to be burned from the catalyst. In some cases, it is advantageous to regenerate the catalyst only partially, for example, by removing about 30-80% by weight of the carbonaceous material.

[0007] Flue gas formed by burning coke in a regenerator is treated to remove particulate matter and convert carbon monoxide to carbon dioxide, possibly recovering power and / or heat, and then the flue gas is usually released into the atmosphere. Furthermore, incomplete combustion of carbon monoxide can result from insufficient fluidization or aeration of the coke catalyst in the regenerator, or from insufficient distribution of the coke catalyst within the regenerator. Generally, flue gas exiting a regenerator contains carbon monoxide, carbon dioxide, nitrogen, and water, along with small amounts of other chemical species. Flue gas treatment methods are effective, but they have high capital and operating costs.

[0008] Due to environmental concerns regarding greenhouse gas emissions, separating greenhouse gases before releasing flue gas into the atmosphere is becoming increasingly important. Carbon dioxide is the most important and longest-living greenhouse gas in the atmosphere. Carbon dioxide capture from flue gas remains expensive in terms of both capital expenditure and operational costs. In fluid catalytic processes, air is used to regenerate spent catalysts. As a result of this operation, carbon dioxide in FCC flue gas has a lower concentration, in contrast to the concentration of undesirable components that hinder carbon dioxide capture. Consequently, high capital expenditures are incurred for large volumes of flue gas, as well as significant operational utility costs such as high solvent circulation rates and solvent regeneration duties. Separately, flue gas requires extensive treatment before carbon capture to meet stringent specifications to avoid high solvent decomposition rates. High capital expenditures and operational utility costs are required by various long-term impurity removal operations.

[0009] An improved process is needed to remove impurities from carbon dioxide-containing flue gas and separate the carbon dioxide product stream to meet applicable specifications. Furthermore, processes and equipment are needed that reduce the capital expenditures and operating costs of the carbon dioxide capture section as part of the flue gas treatment, while improving energy efficiency and energy recovery. [Overview of the initiative]

[0010] This disclosure provides a process and apparatus for separating carbon dioxide product streams from flue gas streams. Synthetic air combustion processes aim to mitigate the harmful effects of emissions by burning carbonaceous or hydrocarbon fuels with an oxidizing medium containing oxygen and carbon dioxide, thereby producing net combustion product gases containing carbon dioxide and water vapor. Synthetic air is considered a method for decarburizing FCC units for future sustainability. Utilizing synthetic air combustion in fluid catalytic reaction units requires a unique carbon dioxide capture process to alter the flue gas composition and facilitate carbon dioxide capture. This disclosure provides a process for removing impurities from regenerator flue gas to target carbon dioxide product specifications. This makes it possible to separate a carbon dioxide product stream from an FCC unit that meets the required carbon dioxide specifications. The advantages of this process include minimizing equipment and costs while removing impurities from the flue gas. [Brief explanation of the drawing]

[0011] Various embodiments are described below with reference to the following drawings, where similar numbers indicate similar elements. [Figure 1] This is a schematic diagram of a process for separating a carbon dioxide product stream from a flue gas stream, according to an exemplary embodiment. [Figure 2] This is a schematic diagram of a process for separating a carbon dioxide product flow from a flue gas flow, according to another exemplary embodiment. [Figure 3] This is a schematic diagram of a process for separating a carbon dioxide product flow from a flue gas flow, according to yet another exemplary embodiment. [Figure 4] This is a schematic diagram of a process for separating a carbon dioxide product flow from a flue gas flow, according to yet another exemplary embodiment.

[0012] definition The term "communication" means that the flow of material between the listed components is functionally enabled.

[0013] The term "downstream communication" means that in downstream communication, at least a portion of the material flowing to the target component (subject) is functionally capable of flowing from the source component (object).

[0014] The term "upstream connection" means that in an upstream connection, at least a portion of the material flowing from the target component can functionally flow to the component from which it is connected.

[0015] The terms "direct connection" or "direct" mean that the flow from the upstream components enters the downstream components without passing through fractionation or transformation units and undergoing compositional changes due to physical fractionation or chemical transformation.

[0016] The term “column” refers to a distillation column (singular or plural) for separating one or more different volatile components. Unless otherwise specified, each column includes a condenser at the top of the column to condense and reflux a portion of the top flow returning to the top of the column, and a reboiler at the bottom of the column to vaporize a portion of the bottom flow and return it to the bottom of the column. The feed into the column may be preheated. The top pressure is the pressure of the top vapor at the vapor outlet of the column. The bottom temperature is the liquid bottom outlet temperature. The top line and bottom line refer to the net lines from the column downstream of any reflux or reboil into the column. A stripper column omits the reboiler at the bottom of the column and instead may provide heating requirements and separation propulsion from a fluidized inert medium such as vapor. A stripper column typically feeds the feed into a top tray and collects the main product from the bottom.

[0017] As used herein, the term “separator” means a vessel having an inlet and at least a top vapor outlet and a bottom liquid outlet, and which may also have an aqueous outlet from the boot. A flash drum is a type of separator that can be downstream-communicated with a separator that can operate at higher pressures.

[0018] As used herein, the term “component-rich flow” means that a rich flow exiting a container has a higher concentration of components than the feed into the container.

[0019] As used herein, the term “concentrated” means more than 50%, preferably more than 75%, and more preferably more than 90%. [Modes for carrying out the invention]

[0020] In Figure 1, a process 101 for separating a carbon dioxide product stream from a flue gas stream is shown according to an exemplary embodiment. Process 101 includes a regenerator 125, a heat recovery section 121, a contaminant removal unit 190, and a carbon dioxide separation section 111. The feed stream in line 105 is sent to a fluid catalytic reactor 110, such as an FCC unit. Catalyst products are separated from the catalyst, and the product-containing stream in line 115 is sent for further processing. The spent catalyst stream in line 120 is sent to the regenerator 125, where the coke on the catalyst is burned to regenerate the catalyst. The regenerated catalyst stream in line 130 is taken out of the regenerator 125 and returned to the fluid catalytic reactor 110. The gas stream is also sent to the regenerator 125. In one aspect of this disclosure, the regenerator 125 may be an FCC regenerator.

[0021] According to this disclosure, the carbon dioxide and oxygen flow in line 135 is also sent to regenerator 125 to regenerate the catalyst flow taken in line 130, generating a flue gas flow in line 150 containing carbon oxides, nitrogen oxides, catalyst fines, oxygen, and water.

[0022] In a fluid catalyst process, catalyst particles are repeatedly circulated between a reaction zone and a catalyst regenerator unit. During regeneration, coke deposited on the catalyst particles during the reaction in the reaction zone is removed at a high temperature by oxidation in the regenerator 125. Removal of coke deposits restores the activity of the catalyst particles to a point where they can be reused in the reaction zone. The present disclosure is directed to handling flue gas streams from regenerators, including FCC regenerators. The regenerated catalyst is withdrawn from the regenerator unit 125 in line 130 and handled as known in the art.

[0023] In one embodiment, the flue gas flow in line 150 is a carbon dioxide-rich flue gas flow. The flue gas flow in line 150 is hot, and heat can be recovered from the flue gas flow in line 150 before further processing. The flue gas flow in line 150 may be sent to a heat recovery unit 121 to transfer heat from the flue gas flow in line 150, forming a cooled flue gas flow and a steam flow. In an exemplary embodiment, the heat recovery section 121 is a heat recovery steam generator (HRSG) 122. The HRSG 122 includes a superheated steam section 155 and a saturated steam section 165. The flue gas flow in line 150 is sent to the superheated steam section 155 of the HRSG 122 to transfer heat to the primary steam flow in line 161, generating a superheated steam flow in line 172 and a heat-exchanged flue gas flow in line 170. The heat-exchanged flue gas flow in line 170 is sent to the saturated steam section 165 of HRSG 122. In the saturated steam section 165, the boiler feedwater flow 175 is heated by the heat-exchanged flue gas flow in line 170 to produce a saturated steam flow in line 160 and a partially cooled flue gas flow in line 185. The condensed flow in line 180 is taken out of the saturated steam section 165. The primary steam flow in line 161 taken from the saturated steam flow 160 is sent to the superheated steam section 155 for superheating. The remaining steam flow in line 163 taken from the saturated steam flow in line 160 can be taken out as needed and sent to other parts of the plant for use. The partially cooled flue gas flow in line 185 may be taken out of the saturated steam section 165 and sent to the contaminant removal section 190.

[0024] According to an exemplary embodiment, the regenerator 125 may be a complete combustion regenerator or a complete incineration regenerator. In the case of a complete combustion regenerator, the heat recovery section 121 includes only the HRSG unit 122. A complete combustion regenerator does not require a CO combustor 151 for combusting carbon monoxide (CO) into carbon dioxide. Accordingly, within the complete combustion regenerator 125, the flue gas stream in line 150 is sent to the HRSG unit 122. The complete combustion or partial combustion regenerator may be operated at a temperature ranging from about 670°C to about 740°C, or from about 650°C to about 700°C. In the HRSG 122, the high-temperature flue gas indirectly exchanges heat with water to generate steam and a condensed stream, which are taken out from the HRSG 122. The partially cooled carbon dioxide-rich flue gas stream in line 185 is taken out from the heat recovery section 121. The partially cooled carbon dioxide-rich flue gas stream in line 185 is processed to remove impurities. The flue gas outlet temperature from the HRSG 122 for the partial combustion regenerator or complete combustion regenerator 125 may range from about 150°C to about 290°C.

[0025] In one aspect, the disclosed process may include a regenerator 125 operating under a partial combustion or partial incineration mode. In the case of a partial combustion regenerator, the heat recovery section 121 includes a CO combustor 151 upstream of the HRSG 122. When the regenerator unit 150 is operating under partial combustion, a portion of the flow of carbon dioxide and oxygen in line 135 may be taken into line 136 and passed to the CO combustor 151.

[0026] In partial combustion operation, the flue gas stream in line 150 is first sent to the CO combustor in the heat recovery section 121, where carbon monoxide present in the flue gas stream in line 150 is oxidized into carbon dioxide. Then, the completely combusted stream in line 152 from the carbon monoxide combustor is sent to the HRSG 122 in the heat recovery section 121. In an exemplary embodiment, the flue gas outlet temperature of the regenerator 125 for partial combustion or complete combustion operation may range from about 670°C to about 740°C, or from about 650°C to about 700°C. The temperature of the flue gas exiting the CO combustor may range from about 890°C to about 1040°C.

[0027] In the contaminant removal section 190, impurities present in the partially cooled flue gas flow in line 185 may be separated to provide a purified partially cooled flue gas flow. In one exemplary embodiment, the contaminant removal section 190 comprises a contaminant removal reactor 195 and a filtration section 200. The partially cooled flue gas flow in line 185 is sent to the contaminant removal reactor 195. The reactants in line 210 are also sent to the contaminant removal reactor 195. In one embodiment, the reactants in line 210 may include dry reactants or a solution / slurry flow of reactants. Depending on the hydraulic pressure of the system, a blower (not shown) may be added either upstream or downstream of the contaminant removal reactor 195 to increase the pressure of the flue gas flow.

[0028] In some embodiments, NOx compounds are reacted in a NOx reaction section (not shown) before the contaminant removal reactor 190. The NOx reaction section is where the nitrogen oxide-containing compounds are at a lower concentration compared to the inflow. X A selective catalytic reduction (SCR) reactor may be included to form the reactor effluent flow. Any suitable SCR catalyst can be used, including, but is not limited to, ceramic support materials such as titanium oxide having an active catalytic component such as a base metal oxide including TiO2, WO3, and V2O5, or activated carbon-based catalysts. The ammonia flow and / or urea flow are NO X It is introduced into the reactor section, where NO present in the inflow. X It reacts with. If a NOx reaction section is included, the effluent from the NOx reaction section will contain a lower concentration of NOx compounds than the concentration of NOx compounds in the influent.

[0029] In some embodiments, the HRSG is included before the SOx reaction section and / or the NOx reaction section.

[0030] In one exemplary embodiment, the reactants in line 210 are in a dry form. In the case of a dry reactant, the partially cooled flue gas stream in line 185 from the heat recovery section 121 and the dry reactant flow in line 210 are sent to the contaminant removal reactor 195, where the reactants react with sulfur-containing compounds and / or nitrogen-containing compounds in the partially cooled flue gas stream in line 185 to form a reactor outflow flow containing reactant salts or reaction products. In one exemplary embodiment, the contaminant removal reactor 195 may operate at a temperature of about 200°C to about 600°C or about 300°C to about 600°C to react one or more sulfur-containing compounds or nitrogen-containing compounds, or both, in the partially cooled flue gas stream in line 185 with the dry reactant flow in line 210. In another exemplary embodiment, the reaction flow in line 210 includes one or more of sodium bicarbonate (NaHCO3), calcium hydroxide (Ca(OH)2), and trona salt (Na2CO3·NaHCO3·2H2O). In yet another exemplary embodiment, the reactant salt includes one or more of sodium sulfate (Na2SO4), sodium carbonate (Na2CO3), and sodium nitrate (NaNO3). The reactor outflow flow containing the reactant salt is sent to filter section 200 for particle removal.

[0031] The filter section 200 removes particulate matter, reactant salts, and catalyst fines from the reactor effluent. In an exemplary embodiment, SOx reaction products are filtered from the dry SOx reaction section flue gas flow within the filter section 200 to form a filtered material flow in line 215. If the filter section 200 includes an electrostatic precipitator, electricity may be supplied to the filter section 200. The filter section 200 may also include a bag filter. The filtered material from the filter section 200 may include reactant salts and catalyst fines that can be removed in the filter section 200. The filtered material can be removed from the process in line 215. Alternatively or additionally, the filtered material can be recycled to the contaminant removal reactor 195. The filtered, SOx and / or NOx-purified reactor effluent in line 220 is sent to the carbon dioxide separation section 111 to separate the carbon dioxide product flow from the filtered reactor effluent. The separation section 111 may include one or more heat exchangers, coolers, knock-out drums (KODs), heaters, and compressors.

[0032] Since the reactants are used in a dry form, the filtered reactor effluent in line 220 still has a fairly high temperature. Heat / energy can still be recovered from the filtered reactor effluent in line 220. The filtered reactor effluent in line 220 can pass through an optional first heat exchanger 225 to recover some heat from the filtered reactor effluent in line 220, and then be sent to the downstream separation section 111. The first heat-exchanged flue gas flow in line 230 is sent to a second heat exchanger 235, where it is heat-exchanged with the first carbon dioxide recirculation flow in line 344 to form a first preheated carbon dioxide recirculation flow in line 347 and a second cooled flue gas flow in line 250. The second cooled flue gas flow in line 250 can be cooled or optionally condensed in the third heat exchanger 251 to provide a final cooled flue gas flow in line 253. The final cooled flue gas flow in line 253 is separated to provide a carbon dioxide product flow, a carbon dioxide recirculation flow, and an oxygen-rich flow.

[0033] After heat exchange, the finally cooled flue gas flow in line 253 is sent to a knockout drum (KOD) 255 to remove the water flow in line 260 and form a partially dehydrated flue gas flow in line 265. From the top of the KOD, the partially dehydrated flue gas flow in line 265 is sent to a dewatering unit 280. The water flow in line 260 is removed from the bottom of the KOD 255. In one exemplary embodiment, the partially dehydrated flue gas flow in line 265 contains less than about 15 volume percent, or less than about 10 volume percent, or less than about 5 volume percent of water.

[0034] The partially dehydrated flue gas flow in line 265 can be compressed in compressor 270 before being sent to dewatering unit 280. Dewatering unit 280 dewaters the flow 285 to prevent hydrate (ice) formation under cryogenic conditions in cryogenic fractionation column 290. Both solid and liquid desiccants can be used for this purpose. In one exemplary embodiment, the partially dehydrated flue gas flow in line 265 can be compressed to a pressure of about 3,000 to about 6,000 kPa(a) in compressor 270. The compressed flue gas flow in line 275 is sent to dewatering unit 280. Dewatering unit 280 can be operated at a pressure of about 3,000 kPa(a)(60 psia) to about 6,000 kPa(a)(600 psia) and a temperature of about 10°C(50°F) to about 66°C(50°F). In the dewatering unit 280, water is removed from the compressed flue gas flow or the partially dewatered flue gas flow to generate a dewatered flue gas flow in line 285. In the outlet line 282, the water flow is removed from the dewatering unit 280.

[0035] In one embodiment, the dewatered flue gas flow in line 285 can be separated in a cryogenic fractionation unit. In one embodiment, the cryogenic fractionation unit comprises a cryogenic fractionation column 290 and a compressor 292. According to this disclosure, the cryogenic fractionation column 290 can be operated at a temperature of about -20°C to about -50°C and a pressure of about 3000 kPa(a) to 6000 kPa(a). A liquid CO2 flow is recovered from the cryogenic fractionation column. A mixed refrigerant flow is used in the cryogenic fractionation column to recover the liquid CO2 flow. The compressor 292 is used to compress the mixed refrigerant flow, which is then expanded to extract cooling capacity for the cryogenic fractionation unit. In one embodiment, the mixed refrigerant flow may contain hydrocarbon and non-hydrocarbon components that can be appropriately selected to provide the most efficient cooling capacity to the cryogenic fractionation column 290.

[0036] The dehydrated flue gas flow in line 285 can optionally be mixed with the compressed oxygen-rich flow in line 308 to provide a mixed dehydrated flue gas flow in line 286. The mixed dehydrated flue gas flow in line 286 is sent to the cryogenic fractionation column 290. In the cryogenic fractionation column 290, the mixed dehydrated flue gas flow in line 286, or the dehydrated flue gas flow in line 285 if there is no recirculation of the compressed oxygen-rich flow in line 308, is fractionated to separate oxygen from carbon dioxide. A mixed refrigerant flow is also used in the cryogenic fractionation column 290 to recover a liquid CO2 flow from the mixed dehydrated flue gas flow in line 286 or the dehydrated flue gas flow in line 285. The mixed refrigerant flow is compressed in a compressor 292 and then expanded to extract cooling capacity for the cryogenic fractionation unit. The oxygen-rich flow in line 300 is taken out of the cryogenic fractionation column 290. The carbon dioxide product stream is separated from the cryogenic fractionation column 290 in line 295. In one embodiment, the carbon dioxide stream in line 325, which has been removed from the carbon dioxide product stream in line 295, can be recycled to provide a flow of carbon dioxide and oxygen in line 135.

[0037] The oxygen-rich flow in line 300 may be further processed to provide a purified oxygen flow. According to this disclosure, the oxygen-rich flow in line 300 contains at least about 50 mol% oxygen and at least about 10 mol% carbon dioxide. In one embodiment, the oxygen-rich flow in line 300 contains about 50 to about 90 mol% oxygen and about 10 to about 50 mol% carbon dioxide. In one exemplary embodiment, the oxygen-rich flow in line 300 is separated into a first oxygen-rich flow in line 302 and a second oxygen-rich flow in line 304. In one embodiment, the second oxygen-rich flow in line 304 can be expanded to extract energy. The first oxygen-rich flow in line 302 is compressed in a compressor 307 to provide a compressed oxygen-rich flow in line 308. The compressed oxygen-rich flow in line 308 is recycled to a cryogenic fractionation column 290 from which carbon dioxide is recovered. The second oxygen-rich flow in line 304 can pass through the expander 305, compressor 305, or JT valve 305 to provide a purified oxygen flow in line 310. The purified oxygen flow in line 310 may be further used in process 101 as a supplement oxygen supply gas to regenerator 125, or it may be purged into the atmosphere. Alternatively, the purified oxygen flow in line 310 can be used as a supplement oxygen supply gas to the process.

[0038] Upon returning to the cryogenic fractionation column 290, the carbon dioxide product stream in line 295 may optionally be separated into a recirculated carbon dioxide product stream in line 325 and a net carbon dioxide product stream in line 296. The net carbon dioxide product stream in line 296 may be removed. Optionally, the recirculated carbon dioxide product stream in line 325 may be recycled to the regenerator 125. In one exemplary embodiment, the recirculated carbon dioxide product stream in line 325 may constitute about 10% to about 60% of the carbon dioxide product stream in line 295.

[0039] Referring back to KOD255, the partially dehydrated flue gas flow in line 265 may be separated to provide a carbon dioxide recirculation flow before proceeding to the downstream cryogenic fractional distillation column 290. In one exemplary embodiment, the partially dehydrated flue gas flow in line 265 may be separated into a first partially dehydrated flue gas flow in line 266 and a second partially dehydrated flue gas flow in line 330. The first partially dehydrated flue gas flow in line 266 may be sent to the dehydration unit 280 and processed as described above.

[0040] The second partially dehydrated flue gas flow in line 330 can be recirculated to the regenerator 125. In one embodiment, the second partially dehydrated flue gas flow in line 330 can be compressed in compressor 335 to provide a carbon dioxide recirculation flow in line 140, which can be sent to the regenerator 125. In another exemplary embodiment, the second partially dehydrated flue gas flow in line 330 can be separated into a first carbon dioxide recirculation flow in line 340 and a second carbon dioxide recirculation flow in line 341. The first carbon dioxide recirculation flow in line 340 can be sent to a second heat exchanger 235 to exchange heat with the first heat-exchanged flue gas flow in line 230. In one exemplary embodiment, the first carbon dioxide recirculation flow in line 340 can be mixed with the recirculated carbon dioxide product flow in line 325 to provide a mixed carbon dioxide recirculation flow in line 344. The mixed carbon dioxide recirculation flow in line 344 can exchange heat with the first heat-exchanged flue gas flow in line 230 in the second heat exchanger 235. Optionally, the recirculated carbon dioxide product flow in line 325 can be sent to the expansion valve 327 to provide an expanded recirculated carbon dioxide product flow in line 328. The expanded recirculated carbon dioxide product flow in line 328 can be mixed with the first carbon dioxide recirculation flow in line 340. Optionally, the net carbon dioxide product flow in line 296 may be used as a coolant flow (not shown) in the third heat exchanger 251 before being sent to the product destination. Alternatively, the net carbon dioxide product flow in line 296 can be used as a coolant flow (not shown) to maintain the compressed flue gas flow in line 275 at an optimal temperature before being sent to the dewatering unit 280.

[0041] After heat exchange in the second heat exchanger 235, a first preheated carbon dioxide recirculation flow is provided into line 347. The second carbon dioxide recirculation flow in line 341 may be mixed with the first preheated carbon dioxide recirculation flow in line 347 to provide a mixed carbon dioxide recirculation flow in line 342. The mixed carbon dioxide recirculation flow in line 342 may be compressed in compressor 335 to provide a compressed carbon dioxide recirculation flow in line 346. The compressed carbon dioxide recirculation flow in line 346 may pass through heat exchanger 345 to recover some heat and provide a heat-exchanged carbon dioxide recirculation flow in line 140, which can be sent to regenerator 125. In one embodiment, the compressed carbon dioxide recirculation flow in line 346 is cooled by heat exchange in heat exchanger 345. In another embodiment, the heat-exchanged carbon dioxide recirculation flow in line 140 is a preheated carbon dioxide recirculation flow. According to one exemplary embodiment of the present disclosure, the carbon dioxide product flow in line 296 may constitute about 10% to about 70% of the heat-exchanged carbon dioxide recirculation flow in line 140.

[0042] In one embodiment, the second partially dehydrated flue gas flow in line 330 is optionally separated into a first carbon dioxide recirculation flow in line 340 and a second carbon dioxide recirculation flow in line 341. In one embodiment, the entirety of the second partially dehydrated flue gas flow in line 330 may be sent to a regenerator 125 in line 341.

[0043] The heat-exchanged carbon dioxide recirculation flow in line 140 can be mixed with the oxygen flow in line 145 to provide a flow of carbon dioxide and oxygen in line 135. The oxygen flow in line 145 can be taken from an oxygen source 141. In one embodiment, the oxygen source 141 for providing the oxygen flow 145 can be selected from an air separation unit (ASU) or an electrolytic cell. In an exemplary embodiment, the oxygen source 141 is an electrolytic cell.

[0044] Various types of electrolytic cells can be used as the electrolytic cell 141, including, but are not limited to, polymer electrolyte membrane / proton exchange membrane (PEM / PEMEC), alkaline electrolysis cell (AEC), anion exchange membrane (AEM), and solid oxide electrolysis cell (SOE / SOEC). According to this disclosure, useful materials produced in the fluid catalyst process may be used in the electrolytic section of the electrolytic cell 141. In PEM, AEC, AEM, and SOEC electrolytic cells, electricity generated in the power recovery section may be used. In addition, in the SOEC electrolytic cell, heat in the form of vapor may be used in the SOEC to reduce the need for utilities that are generated and delivered to the process and apparatus 101. In the SOEC electrolytic cell, about 25% to about 30% of the total energy requirement may be supplied by heat. In one exemplary embodiment, heat generated from a regenerator in the flue gas may be supplied to the SOEC electrolytic cell. Apart from extracting heat from the flue gas of the regenerator, other heat sources, such as heat extracted from the top of the main column of the FCC unit, are also envisioned for integration. Furthermore, apart from using electricity to split water, the electricity generated in the process unit as disclosed above may also be used for compression in electrolytic cells such as AEC, AEM, and PEM electrolytic cells. In one embodiment, the electrolytic cell 141 may use thermal energy or steam generated in the catalyst regeneration process.

[0045] Referring to Figure 1, the oxygen source 141 may be an electrolytic cell 141. The electrolytic cell 141 may be selected from one or more electrolytic cells, including but not limited to polymer electrolyte membranes / proton exchange membranes (PEM / PEMEC), alkaline electrolytic cells (AEC), anion exchange membranes (AEM), and solid oxide electrolytic cells (SOE / SOEC), as described above. Airflow in line 142 and waterflow in line 144 are supplied to the electrolytic cell 141. Heat 143 is also supplied to the electrolytic cell 141 from any suitable heat source. In one exemplary embodiment, the heat 143 to the electrolytic cell 141 is supplied from any suitable process unit of the fluid catalyst unit. However, the heat to the electrolytic cell 141 can be supplied from any other heat source. Various utilities generated in the fluid catalyst unit can be used in the electrolytic cell 141. In one embodiment, electricity from the expander 305, a superheated steam flow in line 172 from the superheated steam section 155 of HRSG 121, and a saturated steam flow in line 163 from the saturated steam section 165 of HRSG 122 may also be supplied to the electrolytic cell 141. The oxygen flow is taken out of the electrolytic cell 141 in line 145 and mixed with the heat-exchanged carbon dioxide recirculation flow in line 140 to provide a flow of carbon dioxide and oxygen in line 135, which is supplied to the regenerator 125.

[0046] Referring here to Figure 2, another exemplary embodiment of a process for separating carbon dioxide products from a flue gas stream is discussed with reference to process and apparatus 201. The elements of Figure 2 may have the same configuration as those in Figure 1, each having the same reference numerals, and similar operating conditions. Process 201 for separating a carbon dioxide product stream from a flue gas stream includes a contaminant removal section operating under humid conditions to remove one or more of sulfur-containing compounds, nitrogen-containing compounds, or both from the flue gas stream.

[0047] The partially cooled flue gas flow in line 185 is processed in a decontamination section 190' to remove contaminants. In one exemplary embodiment, the partially cooled flue gas flow in line 185 is heat-exchanged with a carbon dioxide recirculation flow in a first heat exchanger 225' to provide a heat-exchanged and cooled flue gas flow in line 186. After heat exchange, the heat-exchanged and cooled flue gas flow in line 186 is sent to a decontamination section 190', which includes a decontamination reactor 195'. In one embodiment, the first heat exchanger 225' is optional, and the partially cooled flue gas flow in line 185 may be sent directly to the decontamination reactor 195'. In the embodiment shown in process 201, the decontamination reactor 195' includes a wet SOx reaction section for removing SOx compounds from the flue gas flow in line 186. A flow containing an alkaline solution in line 210' is sent to the decontamination reactor 195'. Optionally, the ozone stream in line 192 may also be sent to the contaminant removal reactor 195'. In the wet SOx reaction section, the alkaline solution reacts with SOx compounds in the heat-exchanged and cooled flue gas stream in line 186, and optional ozone reacts with NOx compounds in the heat-exchanged and cooled flue gas stream in line 186. Washing with water removes particulate matter from the heat-exchanged and cooled flue gas stream in line 186, forming the reactor outflow stream. The liquid slurry stream is separated from the reactor outflow stream and taken out into line 215'. The reactor outflow gas stream in line 220' is sent to the carbon dioxide separation section 111 to separate the carbon dioxide product stream.

[0048] The reactor effluent gas flow in line 220' is sent to a second heat exchanger 235, where it exchanges heat with the first carbon dioxide recirculation flow in line 340 to provide a first partially preheated carbon dioxide recirculation flow in line 347' and a second cooled flue gas flow in line 250'. The second cooled flue gas flow in line 250' can be cooled in a third heat exchanger 251 or optionally condensed to provide a finally cooled flue gas flow in line 253'. The finally cooled flue gas flow in line 253' is sent to KOD 255. The first partially preheated carbon dioxide recirculation flow in line 347' may exchange heat with the partially cooled flue gas flow in line 185 in a first heat exchanger 225' to provide a first preheated carbon dioxide recirculation flow in line 348. A first preheated carbon dioxide recirculation flow in line 348 may be mixed with a second preheated carbon dioxide recirculation flow in line 341 to provide a heat-exchanged carbon dioxide recirculation flow in line 140, which is then sent to the regenerator 125 via line 135. In one embodiment, a first partially preheated carbon dioxide recirculation flow in line 347' may be mixed with a second preheated carbon dioxide recirculation flow in line 346 to provide a heat-exchanged carbon dioxide recirculation flow in line 140. The remainder of the process is the same as described in Figure 1.

[0049] Another exemplary embodiment of a process and apparatus for separating a carbon dioxide product flow from a flue gas flow is discussed with reference to a process and apparatus 301 shown in Figure 3. The elements of Figure 3 may have the same configuration as those of Figure 1, and each may have the same reference numerals and similar operating conditions. The process and apparatus for regenerating a catalyst from a fluid catalyst process shown in Figure 3 includes a pressure swing absorption (PSA) unit 311 in addition to the elements shown in Figure 1.

[0050] The oxygen-rich flow in line 300 may contain contaminants that can be separated from the oxygen. These contaminants may include carbon dioxide, carbon monoxide (trace amounts), nitrogen, and argon. The oxygen-rich flow in line 300 may also contain carbon dioxide, which can be further separated to increase the yield of carbon dioxide in the carbon dioxide product flow. In the embodiment shown in process 301, the oxygen-rich flow in line 300 may be sent to a PSA unit 311. In the PSA unit 311, carbon dioxide is separated from the oxygen in the PSA tail gas flow in line 312.

[0051] The oxygen-rich flow in line 300 is supplied to a PSA unit containing multiple beds of adsorbents such as alumina, silica gel, zeolite, activated carbon, metal-organic framework (MOF), or a combination thereof. At high pressures such as 3000 kPa(a) to 6000 kPa(a), carbon dioxide and heavy components are adsorbed into the pores of the adsorbents, while oxygen and light molecules pass through the beds to generate a purified oxygen flow in line 310''. The adsorption process continues until the mass transfer zone of the components that are preferentially adsorbed reaches the outlet end of the bed without substantially penetrating the bed and reaching the purified oxygen flow in line 310''. The pressure in the PSA unit is then reduced to desorb the adsorbed carbon dioxide and other components into a low-pressure tail gas flow in line 312. The PSA tail gas flow in line 312 may be recycled to a cryogenic fractionation column 290 to recover additional carbon dioxide in the carbon dioxide product flow 295. The PSA tail gas flow in line 312 may be a low-pressure carbon dioxide-containing flow. The PSA tail gas flow in line 312 may be compressed in a compressor and recirculated to the cryogenic fractional distillation column 290. In one exemplary embodiment, the PSA tail gas flow in line 312 may be mixed with a first partially dehydrated flue gas flow in line 266 to provide a mixed partially dehydrated flue gas flow in line 267. The mixed partially dehydrated flue gas flow in line 267 can be compressed in a compressor 270 to provide a compressed partially dehydrated flue gas flow in line 275. The compressed partially dehydrated flue gas flow in line 275 can be dehydrated in a dehydration unit 280 to provide a dehydrated flue gas flow in line 285.

[0052] Returning to the PSA unit 311, the purified oxygen stream in line 310'' is taken out from the top of the PSA unit 311. The purified oxygen stream in line 310'' is the high-pressure top stream from the PSA unit 311. The rest of the process is the same as described in Figure 1.

[0053] Another exemplary embodiment of a process and apparatus for separating a carbon dioxide product stream from a flue gas stream is discussed with reference to process and apparatus 401, as shown in Figure 4. The elements of Figure 4 may have the same configuration as those in Figure 1, have the same reference numerals, and have similar operating conditions.

[0054] In the embodiment shown in process 401, the contaminant removal section 190 is located downstream and possibly in direct communication with the cryogenic fractionation column 290. As shown in Figure 4, the contaminant removal section 190 comprises a contaminant removal reactor 195. In this embodiment, a filtration section 200''' is located upstream of the contaminant removal section 190 to remove or filter particulate matter upstream of the contaminant removal section 190, and the inlet flow to the contaminant removal reactor 195 may contain filtered effluent.

[0055] The partially cooled flue gas flow in line 185 may pass through the filtration section 200''' to remove particulate matter, reactant salts, and catalyst fines from the partially cooled flue gas flow in line 185. One or more of the particulate matter, reactant salts, and catalyst fines are removed from the filtration section 200''' into the filter material flow in line 215'''. If the filter section 200''' includes an electrostatic precipitator, electricity may be supplied to the filter section 200'''. The filter section 200''' may also include a bag filter. The filtered flue gas flow is taken out of the filter section 200''' in line 220'''. The filtered flue gas flow in line 220''' may pass through an optional first heat exchanger 225''' to recover some heat before being sent to the downstream separation section 111'''. The first heat-exchanged filtration flue gas flow in line 230''' is sent to the second heat exchanger 235''', where it is heat-exchanged with the first carbon dioxide recirculation flow in line 344''' to form the first preheated carbon dioxide recirculation flow in line 347''' and the second cooled filtration flue gas flow in line 250'''. The second cooled filtration flue gas flow in line 250''' can be cooled or optionally condensed in the third heat exchanger 251''' to provide the final cooled filtration flue gas flow in line 253'''. The final cooled filtration flue gas flow in line 253''' is separated to provide the carbon dioxide product flow, the carbon dioxide recirculation flow, and the oxygen-rich flow.

[0056] After heat exchange, the cooled filtered flue gas flow in line 253''' is sent to the knockout drum (KOD) 255''' to remove the water flow in line 260 and form a partially dehydrated flue gas flow in line 265'''. The partially dehydrated flue gas flow in line 265''' is sent from the top of the KOD to the dewatering unit 280'''. The water flow in line 260 is removed from the KOD 255'''.

[0057] The partially dewatered flue gas flow in line 265''' may be compressed in compressor 270 before being sent to dewatering unit 280'''. The compressed flue gas flow in line 275''' is sent to dewatering unit 280'''. In dewatering unit 280''', water is removed from the compressed flue gas flow or the partially dewatered flue gas flow to generate a dewatered flue gas flow in line 285'''. The water flow in line 282 is removed from dewatering unit 280'''.

[0058] In one embodiment, the dehydrated flue gas flow in line 285''' may be separated in a cryogenic fractionation column 290'''. In one embodiment, the cryogenic fractionation column comprises a cryogenic fractionation column 290''' and a compressor 292'''. The dehydrated flue gas flow in line 285''' may optionally be mixed with a compressed oxygen-rich flow in line 308''' to provide a mixed dehydrated flue gas flow in line 286'''. The mixed product water flow in line 286''' is sent to the cryogenic fractionation column 290'''. In the cryogenic fractionation column 290''', the mixed dehydrated flue gas flow in line 286''' or the dehydrated flue gas flow in line 285''' is fractionated to separate the bottom flow, which includes oxygen in the top line 300''', possibly carbon dioxide in the intermediate flow 295''' from the side of the column, and a heavier liquid flow in line 297. The oxygen-rich flow in line 300''' is removed from cryogenic fractionation column 290'''. The carbon dioxide product flow is separated from cryogenic fractionation column 290''' in line 295'''.

[0059] The heavy liquid stream in line 297 is also withdrawn from the bottom of the cryogenic fractionation column 290'''. The heavy liquid stream in line 297 contains sulfur oxides and / or nitrous oxide. The heavy liquid stream in line 297 may be treated to recover the sulfur oxides and / or nitrous oxide. In the embodiment shown in process 401, the heavy liquid stream in line 297 is sent to a contaminant removal section 190''' to remove contaminants, providing an outflow stream into line 299 with substantially less contaminants, including sulfur oxides and / or nitrous oxide, compared to the heavy liquid stream in line 297. The contaminant removal section 190''' comprises a contaminant removal reactor 195'''.

[0060] In one exemplary embodiment, the heavy liquid stream in line 297 may be brought into contact with reactants in a contaminant removal reactor 195''' and treated with the reactants. Reactants (not shown) may be sent to the contaminant removal reactor 195'''. In the contaminant removal reactor 195''', the reactants react with sulfur-containing compounds and / or nitrogen-containing compounds in the heavier liquid stream in line 297. The reacted compounds may be separated, and the effluent in line 299 is removed from the contaminant removal reactor 195'''.

[0061] Returning to KOD255''', the partially dehydrated flue gas flow in line 265''' may be separated to provide a carbon dioxide recirculation flow before being sent to the downstream cryogenic fractional distillation column 290. In one exemplary embodiment, the partially dehydrated flue gas flow in line 265''' may be separated into a first partially dehydrated flue gas flow in line 266''' and a second partially dehydrated flue gas flow in line 330'''. The first partially dehydrated flue gas flow in line 266''' may be sent to the dehydration unit 280''' and processed as described above.

[0062] The second partially dehydrated flue gas flow in line 330''' can be recirculated to the regenerator 125. In one embodiment, the second partially dehydrated flue gas flow in line 330''' can be compressed in compressor 335''' to provide a carbon dioxide recirculation flow in line 140''', which can be sent to the regenerator 125. In an exemplary embodiment, the second partially dehydrated flue gas flow in line 330''' can be separated into an optional first carbon dioxide recirculation flow in line 340''' and a second carbon dioxide recirculation flow in line 341'''. The first carbon dioxide recirculation flow in line 340''' can be sent to a second heat exchanger 235''' to exchange heat with the first heat-exchanged filtered flue gas flow in line 230'''. In one exemplary embodiment, the first carbon dioxide recirculation flow in line 340''' can be mixed with the recirculated carbon dioxide product flow in line 325''' to provide a mixed carbon dioxide recirculation flow in line 344'''. In one embodiment, the recirculated carbon dioxide product flow in line 325''' can be sent to an expansion valve to provide an expanded recirculated carbon dioxide product flow in line 328'''. This can be mixed with the first carbon dioxide recirculation flow in line 340'''. The mixed carbon dioxide recirculation flow in line 344''' can be heat-exchanged with the first heat-exchanged filtered flue gas flow in line 230''' in a second heat exchanger 235'''. After heat exchange in the second heat exchanger 235''', a first preheated carbon dioxide recirculation flow is provided in line 347'''. The second carbon dioxide recirculation flow in line 341'' may be mixed with the first preheated carbon dioxide recirculation flow in line 347'' to provide a mixed carbon dioxide recirculation flow in line 342''. The mixed carbon dioxide recirculation flow in line 342'' may be compressed in compressor 335'' to provide a compressed carbon dioxide recirculation flow in line 346''. The compressed carbon dioxide recirculation flow in line 346'' may pass through heat exchanger 345'' to recover some heat and provide a heat-exchanged carbon dioxide recirculation flow in line 140'', which may be sent to regenerator 125. In one embodiment, the compressed carbon dioxide recirculation flow in line 346''' is cooled by heat exchange in heat exchanger 345''.In another embodiment, the heat-exchanged carbon dioxide recirculation flow in line 140''' is a preheated carbon dioxide recirculation flow. The remainder of the process and the remainder of the description are the same as those described in Figure 1.

[0063] Any of the lines, conduits, units, devices, containers, surrounding environments, zones, or similar entities described above may comprise one or more monitoring components, including sensors, measuring devices, data acquisition devices, or data transmission devices. Signals, process, or state measurements, and data from the monitoring components can be used to monitor conditions within, around, and on process equipment. Signals, measurements, and / or data generated or recorded by the monitoring components may be collected, processed, and / or transmitted via one or more networks or connections, which may be private or public, general or specific, direct or indirect, wired or wireless, encrypted or unencrypted, and / or a combination thereof. This specification is not intended to limit it in this respect. Furthermore, the figures may include one or more exemplary sensors placed on one or more conduits. Nevertheless, sensors may be present on each flow so that corresponding parameters can be controlled accordingly.

[0064] Signals, measurements, and / or data generated or recorded by monitoring components may be transmitted to one or more computing devices or systems. A computing device or system may include at least one processor and memory for storing computer-readable instructions that, when executed by at least one processor, cause one or more computing devices to perform a process that may include one or more steps. For example, one or more computing devices may be configured to receive data from one or more monitoring components relating to at least one part of equipment associated with a process. One or more computing devices or systems may be configured to analyze the data. Based on the analysis of the data, one or more computing devices or systems may be configured to determine one or more recommended adjustments to one or more parameters of one or more processes described herein. One or more computing devices or systems may be configured to transmit encrypted or unencrypted data containing one or more recommended adjustments to one or more parameters of one or more processes described herein.

[0065] Specific Embodiments The following will be explained in conjunction with specific embodiments, but it should be understood that this explanation is intended to illustrate the scope of the preceding explanation and the attached claims, and is not intended to limit them.

[0066] A first embodiment of the present disclosure is a process for separating a carbon dioxide product stream from a flue gas stream, the process comprising: regenerating a catalyst stream by passing a stream of carbon dioxide and oxygen through a regenerator to generate a flue gas stream containing carbon oxides, sulfur oxides and / or nitrogen oxides, catalyst particles, oxygen, and water; transferring heat from the flue gas stream to a water stream in a heat recovery unit to form a steam stream; removing at least one of sulfur oxides, nitrogen oxides, and catalyst particles from the flue gas stream in a contaminant removal unit; removing water from the flue gas stream in a dewatering unit; and separating the flue gas stream into an oxygen-rich stream and a carbon dioxide product stream. One embodiment of the present disclosure is one or all of the prior embodiments of this paragraph, including the first embodiment of this paragraph, further comprising reacting sulfur oxides with reactants in a contaminant removal unit to remove sulfur oxides from the flue gas stream. Embodiments of the present disclosure are one or all of the prior embodiments of this paragraph, including the first embodiment of this paragraph, and include: sending a flue gas stream to a contaminant removal unit before a dewatering unit; sending a partially cooled flue gas stream from a heat recovery unit to a contaminant removal unit; reacting one or more sulfur-containing compounds, nitrogen-containing compounds, or both in the partially cooled flue gas stream with reactants in a contaminant removal reactor to form a reactor effluent flue gas stream and a contaminant stream; and sending the reactor effluent flue gas stream to a dewatering unit. One embodiment of the present disclosure is one or all of the prior embodiments of this paragraph, including the first embodiment of this paragraph, and further includes: transferring heat from the reactor effluent flue gas stream to provide a cooled flue gas stream; separating water from the cooled flue gas stream in a knockout drum to provide a partially dewatered flue gas stream; and removing water from the partially dewatered flue gas stream in a dewatering unit to provide a dewatered flue gas stream. One embodiment of the present disclosure is one, any, or all of the prior embodiments of this paragraph, including the first embodiment of this paragraph, further comprising taking a carbon dioxide recirculation flow from a partially dehydrated flue gas flow and sending the carbon dioxide recirculation flow to a regenerator.One embodiment of the present disclosure is one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, further comprising fractional distillation of a dehydrated flue gas stream in a cryogenic fractional distillation column to provide an oxygen-rich stream and a carbon dioxide product stream. One embodiment of the present invention is one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, further comprising dividing an oxygen-rich stream into a first oxygen-rich stream and a second oxygen-rich stream, compressing the first oxygen-rich stream to provide a compressed oxygen-rich stream, separating the compressed oxygen-rich stream together with the flue gas stream in a cryogenic fractional distillation column to provide a carbon dioxide product stream, and expanding the second oxygen-rich stream to provide a purified oxygen stream. One embodiment of the present disclosure is one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, further comprising separating a heavy liquid stream containing nitrogen oxides and / or sulfur oxides in a cryogenic fractionation column, and reacting one or more sulfur-containing compounds, nitrogen-containing compounds, or both in the heavy liquid stream with reactants in a contaminant removal reactor to form a reactor effluent flue gas stream and a contaminant stream, wherein the reactor effluent flue gas stream has a concentration of sulfur-containing compounds, nitrogen-containing compounds, or both that is less than the concentration of sulfur-containing compounds, nitrogen-containing compounds, or both in the heavy liquid stream. One embodiment of the present disclosure is one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, further comprising sending an oxygen-rich stream to a pressure swing absorption (PSA) unit, separating the oxygen-rich stream into a purified oxygen stream and a PSA tail gas stream, and recirculating the PSA tail gas stream to a cryogenic fractionation column. Embodiments of the present disclosure are one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, wherein the regenerator is operating under complete combustion conditions. Embodiments of the present disclosure are one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, wherein removing water from a partially dehydrated flue gas flow includes passing a first partially dehydrated flue gas flow taken from the partially dehydrated flue gas flow through a dehydration unit to separate the water and provide a dehydrated flue gas flow.One embodiment of the present disclosure is one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, and further includes taking a second partially dehydrated flue gas flow from a partially dehydrated flue gas flow to provide a carbon dioxide recirculation flow; separating the carbon dioxide recirculation flow into a first carbon dioxide recirculation flow and a second carbon dioxide recirculation flow; heating the first carbon dioxide recirculation flow to generate a preheated first carbon dioxide recirculation flow; mixing the preheated first carbon dioxide recirculation flow and the second carbon dioxide recirculation flow to provide a carbon dioxide recirculation flow; and sending the carbon dioxide recirculation flow to a regenerator. One embodiment of the present disclosure is one or all of the prior embodiments of this paragraph, including up to the first embodiment of this paragraph, and further includes mixing the carbon dioxide recirculation flow with a concentrated oxygen flow taken from an electrolytic cell or air separation unit to provide a carbon dioxide and oxygen flow. One embodiment of the present disclosure is one, any, or all of the prior embodiments of this paragraph, including the first embodiment of this paragraph, wherein the carbon dioxide product flow constitutes about 10% to about 60% of the carbon dioxide recirculation flow. Embodiments of the present disclosure are one or all of the prior embodiments of this paragraph, including the first embodiment of this paragraph, and include reacting one or more sulfur-containing compounds, nitrogen-containing compounds, or both in a partially cooled flue gas stream with a reactant in a contaminant removal reactor, reacting the partially cooled flue gas stream with a dry reactant comprising at least one of NaHCO3, NaHCO3·Na2CO3·2(H2O), CaCO3, Ca(OH)2, and Mg(OH)2 in the dry SOx reaction section of the contaminant removal reactor to form a dry SOx reaction section flue gas stream, and filtering the dry SOx reaction section flue gas stream to remove Na2SO4, CaSO4, MgSO4, and catalyst particles to provide a reactor effluent flue gas stream and a filter material stream. One embodiment of the present disclosure is one or all of the embodiments described in the preceding paragraphs to the first embodiment described in this paragraph, wherein the removal of nitrogen oxides from a flue gas stream includes reacting the nitrogen oxides with ozone to produce oxygen in a pollutant removal unit.Embodiments of the present disclosure are any or all of the embodiments described in the preceding paragraphs to the first embodiment described in this paragraph, and include reacting one or more sulfur-containing compounds, nitrogen-containing compounds, or both in a partially cooled flue gas stream with reactants in a contaminant removal reactor, which includes supplying a partially cooled flue gas stream, an alkaline solution, and optionally ozone gas to the contaminant removal reactor, and reacting the alkaline solution with the partially cooled flue gas stream in the wet SOx reaction section of the contaminant removal reactor to form a reactor effluent flue gas stream and a liquid stream containing at least one of H2O, CO2, CO, N2, O2, Na2SO3, Na2SO4, NaHSO3, Na2CO3, (NH4)2SO4 and catalyst particles. One embodiment of the present disclosure is one or all of the embodiments described in the preceding paragraphs to the first embodiment described in this paragraph, further comprising sending a flue gas flow to a carbon monoxide combustor to convert carbon monoxide into carbon dioxide and provide a carbon dioxide-rich flue gas flow, and sending the carbon dioxide-rich flue gas flow to a heat recovery unit.

[0067] A second embodiment of the present disclosure is a process for separating a carbon dioxide product stream from a flue gas stream, the process comprising: regenerating a catalyst stream by passing a stream of carbon dioxide and oxygen through a regenerator to generate a flue gas stream containing carbon oxides, sulfur oxides and / or nitrogen oxides, catalyst particles, oxygen, and water; transferring heat from the flue gas stream to a water stream in a heat recovery unit to form a steam stream; removing water from the flue gas stream in a separator to provide a partially dehydrated flue gas stream; taking a carbon dioxide recirculation stream from the partially dehydrated flue gas stream; removing water from the partially dehydrated flue gas stream to provide a dehydrated flue gas stream; and separating the dehydrated flue gas stream into an oxygen-rich stream and a carbon dioxide product stream.

[0068] A third embodiment of the present disclosure is a process for separating a carbon dioxide product stream from a flue gas stream, comprising: passing a stream of carbon dioxide and oxygen through a regenerator to regenerate a catalyst stream in complete combustion mode to generate a flue gas stream containing carbon oxides, sulfur oxides and / or nitrogen oxides, catalyst particles, oxygen, and water; transferring heat from the flue gas stream to a water stream in a heat recovery unit to form a steam stream; removing water from the flue gas stream in a dewatering unit; and separating the flue gas stream into an oxygen-rich stream and a carbon dioxide product stream.

[0069] Without further detail, it is expected that a person skilled in the art can use the foregoing description to the fullest extent without departing from the spirit and scope of the disclosure, and can easily identify the essential characteristics of the disclosure, and can make various changes and modifications to the disclosure to suit various uses and conditions. Accordingly, the prior preferred specific embodiments should be interpreted as merely illustrative examples and not in any way limiting the remainder of the disclosure, but are intended to cover various modifications and equivalent configurations included in the appended claims.

[0070] In the above, all temperatures are given in degrees Celsius, and all parts and percentages are based on weight unless otherwise indicated.

Claims

1. A process for separating the carbon dioxide product flow from the flue gas flow, The catalyst flow is regenerated by passing a flow of carbon dioxide and oxygen through a regenerator, generating a flue gas flow containing carbon oxides, sulfur oxides and / or nitrogen oxides, catalyst particles, oxygen, and water. In the heat recovery unit, heat is transferred from the flue gas flow to the water flow to form a steam flow, In the contaminant removal unit, at least one of the sulfur oxides, nitrogen oxides, and catalyst fine particles is removed from the flue gas flow. The dewatering unit removes water from the flue gas flow, The flue gas flow is separated into an oxygen-rich flow and a carbon dioxide product flow, A process that includes this.

2. The process according to claim 1, further comprising reacting the sulfur oxide with a reactant in the contaminant removal unit in order to remove the sulfur oxide from the flue gas flow.

3. The flue gas flow is sent to the contaminant removal unit before the dewatering unit. The partially cooled flue gas flow is sent from the heat recovery unit to the contaminant removal unit, The process involves reacting one or more of the sulfur-containing compounds, nitrogen-containing compounds, or both in the partially cooled flue gas stream with reactants in a contaminant removal reactor to form a reactor effluent flue gas stream and a contaminant stream. The reactor effluent flue gas flow is sent to the dewatering unit, The process according to claim 1, including the process described in claim 1.

4. To transfer heat from the reactor effluent flue gas flow and provide a cooled flue gas flow, To separate water from the cooled flue gas flow within the knockout drum and provide a partially dehydrated flue gas flow, To remove water from the partially dewatered flue gas flow within the dewatering unit and provide a dewatered flue gas flow, The process according to claim 3, further comprising:

5. The process involves extracting a carbon dioxide recirculation flow from the aforementioned partially dehydrated flue gas flow, Sending the aforementioned carbon dioxide recirculation flow to the regenerator, The process according to claim 4, further comprising:

6. The process according to claim 4, further comprising fractional distillation of the dehydrated flue gas flow in a cryogenic fractional distillation column to provide the oxygen-rich flow and the carbon dioxide product flow.

7. The oxygen-rich flow is separated into a first oxygen-rich flow and a second oxygen-rich flow. The first oxygen-rich flow is compressed to provide a compressed oxygen-rich flow. The compressed oxygen-rich flow is separated together with the flue gas flow in a cryogenic fractional distillation column to provide the carbon dioxide product flow. The objective is to expand the second oxygen-rich flow to provide a purified oxygen flow, The process according to claim 1, further comprising:

8. Separating a heavy liquid stream containing nitrogen oxides and / or sulfur oxides in the cryogenic fractional distillation column, The process according to claim 7, further comprising reacting one or more of the sulfur-containing compound, the nitrogen-containing compound, or both of the heavy liquid stream with reactants in a contaminant removal reactor to form a reactor effluent flue gas stream and a contaminant stream, wherein the reactor effluent flue gas stream has a concentration of the sulfur-containing compound, the nitrogen-containing compound, or both of the heavy liquid stream that is less than the concentration of the sulfur-containing compound, the nitrogen-containing compound, or both of the heavy liquid stream.

9. The oxygen-rich flow is sent to a pressure swing absorption (PSA) unit, The oxygen-rich flow is separated into a purified oxygen flow and a PSA tail gas flow. The PSA tail gas flow is recirculated to the cryogenic fractional distillation column, The process according to claim 1, further comprising:

10. The process according to claim 1, wherein the regenerator is operating under complete combustion conditions.

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