Method and apparatus for producing acetylene, use of a heat pump device in such method or apparatus

Abstract

A method for producing acetylene and synthesis gas by partial oxidation comprises: in a reactor device (2), generating a quenched cracked gas (CG) comprising acetylene and further gas components, and collecting process water (PW) in the reactor device (2); performing a cooling process on the cracked gas (CG) for cooling the acetylene and the further gas components with an input coolant liquid, said cooling process being deployed in a cooling column (3); collecting heated coolant liquid from a sump (35) of the cooling column (3); performing a heat transfer process (HT) for transferring heat from the collected heated coolant liquid into a steam reservoir (6) thereby generating chilled coolant liquid, and / or performing a heat transfer process (HT) for transferring heat from the collected process liquid (PW); processing the generated chilled coolant liquid for generating input coolant liquid for the cooling column (3); and washing and stripping the cracked gas for obtaining acetylene.

Description

[0001] Method and apparatus for producing acetylene, use of a heat pump device in such method or apparatus

[0002] This disclosure relates to processes and apparatuses for producing acetylene deploying a heat transfer process to improve energy efficiency in industrial plants. Further, uses of heat pumps in industrial acetylene production processes are disclosed.

[0003] Acetylene is a primary material for many products from pharmaceuticals, sportswear, upholstery for car seats and personal care products to adhesives, electronic products and dishwashing detergents. Acetylene is found in a variety of goods and is required in many industrial processes, e.g. welding, coating, plastic production etc.

[0004] In industrial chemical plants, acetylene is produced by subjecting hydrocarbons from natural gas or other hydrocarbon containing feedstocks like LPG, Ethane etc.to high temperatures to achieve an incomplete combustion of the hydrocarbons with oxygen. After their exposure to the high temperatures, the cracked gas containing hydrocarbons must be cooled very rapidly which is usually effected by quenching the hot gases with a coolant liquid. Further energy intensive industrial processes are deployed to separate and purify the raw acetylene for subsequent use.

[0005] In conventional acetylene plants, energy is inevitably lost in the process due to reoccurring heating and cooling steps of process gases and liquids thereby reducing energy efficiency. Accordingly, a need exists for enhanced systems and methods of acetylene production whereby an amount of fuels, especially fossil fuels, burned to provide energy is reduced or eliminated.

[0006] Desirably, such systems and methods also provide for an increase in energy efficiency and / or a decrease in emissions, such as emissions of greenhouse gases, by the chemical synthesis plant.

[0007] It is therefore an object of the present disclosure to provide improved methods and apparatuses for producing acetylene with respect to energy efficiency.

[0008] According to a first aspect of this disclosure, a method for producing acetylene and synthesis gas by partial oxidation is disclosed, the method comprising: a reactor device, generating a cracked gas comprising acetylene and further gas components, and collecting process liquid from a quench of the reactor device; performing a cooling process on the cracked gas for cooling the acetylene and the further gas components, e.g. such as synthesis gas, with an input coolant liquid, said cooling process being deployed in a subsequent cooling column; collecting heated coolant liquid from a sump of the cooling column; performing a heat transfer process for transferring heat from the collected heated coolant liquid into a steam reservoir thereby generating chilled coolant liquid, and / or performing a heat transfer process for transferring heat from the collected process liquid into the steam reservoir; processing the generated chilled coolant liquid for generating input coolant liquid for the quench column; and washing and stripping the cracked gas for obtaining acetylene.

[0009] According to a further aspect, an apparatus or chemical plant for producing acetylene and synthesis gas by partial oxidation is disclosed, the apparatus comprising: a reactor device configured to generate a cracked gas comprising acetylene and further gas components, the reactor device further configured to quench the hot reaction gas and / or to collect process liquid; a cooling column configured to cool the acetylene and the further gas components with an input coolant liquid; and a heat pump device communicatively coupled to a sump of the quench column for collecting heated coolant liquid, and / or being communicatively coupled to the reactor device for collecting process liquid, the heat pump device being implemented to transfer heat from heated coolant liquid and / or the process liquid into a steam reservoir. The heat pump device may be provided downstream of the cooling column and / or the reactor device.

[0010] In embodiments, the apparatus is implemented to carry out the method and / or method steps according to the first aspect as disclosed above or below respect to embodiments or examples.

[0011] Generating a cracked gas may include performing partial oxidation on a (natural) gas comprising hydrocarbons along a conventional Sachsse-Bartholome process.

[0012] The process liquid from the quench of the reactor device and / or the heated coolant liquid from the sump of the cooling column occurs at temperatures that allow for an efficient heat transfer to another medium. For example, the process liquid collected from the reactor device has a temperature between 85 °C and 95 °C at a pressure between 1.0 and 1.5 bara. The heated coolant liquid collected from the sump of the cooling column may have a temperature between 75 °C and 85 °C at a pressure between 1.0 and 1.5 bara. In embodiments, the method includes conveying heated process liquid from the sump of the re- actor / cracking combustion device to the sump of the cooling column. Ducts or pipes may be used to conduct the respective liquid to the facilities implementing the heat transfer process.

[0013] In embodiments, the cooling process may involve a quench process and a quench column.

[0014] The steam reservoir may be a tank or a network implemented to provide process steam at a specific temperature and pressure. The heat transfer process may include generating steam and supplying the generated steam into the reservoir, tank, grid or network. In embodiments, the steam reservoir contains steam at temperatures between 125 °C and 200 °C at a pressure between 1.5 and 2.0 barg. In first alternative embodiments, the steam reservoir contains steam at temperatures between 150 °C and 200 °C and at pressures between 4.0 and 5.8 barg. In second alternative embodiments, the steam reservoir contains steam at temperatures between 185 °C and 250 °C and at pressures between 11.0 and 13.0 barg. In third alternative embodiments, the steam reservoir contains steam at temperatures between 200 °C and 250 °C and at pressures between 15.0 and 17.8 barg. In fourth alternative embodiments, the steam reservoir contains steam at temperatures between 260 °C and 350 °C and at pressures between 15.5 and 22.0 barg. One may also contemplate of temperatures between 250 °C and 450 °C at pressures between 40.0 and 420 barg for the steam in the steam reservoir.

[0015] One may contemplate of a steam temperature of 127 °C at 1.5 barg pressure for some embodiments.

[0016] In particular, the suggested method and apparatus provide heated steam in the steam reservoir by recovering energy from the process liquid or coolant liquid thereby increasing energy efficiency of acetylene production.

[0017] The steam from the steam reservoir may be used as process steam as a source of energy in a chemical plant, in particular the chemical plant for producing acetylene. Process steam is used in production, for example, to dry products, heat up reactors or for distilling. Recovering heat from production facilities as the reactor device and / or the cooling column reduces the CO2 imprint of the acetylene process and / or other chemical plants demanding process steam.

[0018] In embodiments, the steam from the reservoir including heated steam from the heat transfer process, is deployed downstream of the cooling column in the apparatus for producing acetylene, in particular for heating purposes. The process liquid and / or the coolant liquid is or comprises water in embodiments.

[0019] In embodiments, processing the generated chilled coolant liquid includes: passing the generated chilled coolant liquid through a heat exchanger for generating the input coolant liquid for the cooling column, said heat exchanger deploying a secondary coolant liquid. The secondary coolant liquid may be cool water at ambient temperatures, or below 40 °C.

[0020] Through the heat transfer process at the heated coolant liquid, the temperature of the respective coolant liquid is reduced to that the chilled coolant liquid is applicable as input coolant liquid. This may comprise a cooling step in terms of the heat exchanger and the secondary coolant liquid. For example, the secondary coolant liquid has a temperature between 25 °C and 35 °C at a pressure between 2.5 and 3.5 bara. In embodiments, the input coolant liquid for the cooling column has a temperature between 30 °C and 35 °C at a pressure between 2.8 and 3.2 bara.

[0021] In embodiments, the heat transfer process is deployed in a heat pump device, in particular an open loop heat pump. In this disclosure, an open loop heat pump is considered a thermodynamic device that implements a process to evaporate and pressurize feed water into process steam using heat or thermal energy from the process liquid and / or the coolant liquid. In embodiments, the heat pump device is implemented to generate more than 30 t / h in steam mass, preferably more than 50 t / h, and more preferred between 80 t / h and 130 t / h.

[0022] In embodiments, the amount of generated steam exceeds the amount of steam required to execute the acetylene production process. For example, conventional acetylene plants may use 25 t / h process steam, and the heat transfer process results in 60 t / h process steam through the recovery of waste heat from the reactor and / or the cooling column.

[0023] In embodiments, the heat transfer process comprises evaporating feed water in a vacuum atmosphere for generating steam. Feed water is, for example demineralized and degassed water.

[0024] In particular, the step of feeding process water and / or heated coolant water into the heat transfer process is carried out.

[0025] Evaporating may be implemented in a flash tank. Feed water at temperatures and pressures between 65 °C and 85 °C, and 2.0 and 5.0 bara, respectively, can be deployed and preheated by a further heat exchanger. In embodiments, between 1 wt.% and 4 wt.% of the process water fed into the heat transfer process, flash tank or flash loop is evaporated and transferred into process team for the steam reservoir.

[0026] In embodiments, consequently, the heat transfer process comprises the steps of: transferring heat from the collected heated coolant liquid and / or the collected process water into a flash loop containing feed water, said feed water acquiring a flash loop temperature; in the flash loop, circulating the feed water under a flash loop pressure such that the flash loop temperature is lower than the boiling temperature of the feed water; in a flash tank coupled to the flash loop, evaporating feed water by decreasing a pressure in the flash tank such that flash loop temperature is at least boiling temperature of the feed water in the flash tank thereby generating steam.

[0027] On embodiments, the generated steam has a temperature between 85°C and 95.

[0028] In the flash tank, pressures are, for example, between 0.1 bara and 1.5 bara.

[0029] In embodiments, the method further comprises compressing the generated steam through one or more compressor devices to a predetermined steam pressure.

[0030] One may contemplate of cascaded steam compressor devices for step-wise increasing the steam pressure same or similar or compatible with the process steam temperatures and pressures as depicted above. For example, the output pressurized steam may have temperatures between 190 °C and 200° at pressures between 6.5 and 7.5 bara, or temperatures and pressures between 185 °C and 195 °C, and between 6.5 and 7.5 bara, respectively.

[0031] In embodiments, at least one of the following steps is carried out: degassing demineralized water for generating feed water, in particular deploying a membrane degassing device, a thermal and / or a vacuum degassing device; preheating the feed water deploying a heat exchanger; and feeding the flash loop with preheated feed water.

[0032] In particular, the feed water is preheated using waste heat from the collected process water and / or heated coolant water.

[0033] In embodiments, a temperature of the collected heated coolant liquid and / or the collected process water (PW) is between 70 °C and 90 °C, preferably between 75 °C and 85 °C, even more preferred between 78 °C and 80 °C. In embodiments, the method further comprises: stripping an acetylene-containing solvent in a reverse flow with a strip gas, for obtaining acetylene and enriched solvent; and heating the enriched solvent deploying vapor retrieved from the steam reservoir.

[0034] In embodiments, the method includes operating a plurality of reactor devices and / or quenching or cooling devices in parallel, wherein the heat transfer process for transferring heat from the collected heated coolant liquid and / or for transferring heat from the collected process water is deployed in one single heat pump device for generating steam for a steam reservoir, in particular for an industrial steam network.

[0035] For example, the heated coolant liquid is collected from a plurality of cooling columns and conveyed to the heat transfer process, e.g. a heat pump arrangement. Additionally, or alternatively process liquid from a plurality of reactor devices implemented to perform partial oxidation on a hydrocarbons-containing gas to generate cracked gas is collected and conveyed to the heat transfer process.

[0036] In embodiments, the method further comprises at least one of the steps of: compressing the cracked gas; cooling the compressed cracked gas; washing the cooled and compressed cracked gas with a solvent for generating acetylene- containing solvent and synthesis gas, wherein, in particular, washing comprises pre-washing and main washing with the solvent; and washing the cracked gas with a solvent for generating acetylene-containing solvent and synthesis gas.

[0037] In embodiments, the method includes the steps of: operating a plurality of reactor devices and / or quenching devices in parallel for executing the method steps according to the above or below aspects in parallel; and deploying the heat transfer process for transferring heat from the collected heated coolant liquid and / or for transferring heat from the collected process liquid in one single heat pump device for generating steam for a steam reservoir, in particular for an industrial steam network.

[0038] In embodiments, the disclosed apparatus further comprises a heat exchanger having an input and an output, the input being coupled to a sump of the cooling column and the output being coupled to a head of the cooling column, wherein the heat exchanger is implemented to cool heated coolant liquid from the sump and / or process water from the reactor device deploying a secondary coolant liquid, and the heat pump device is provided upstream of the heat exchanger.

[0039] In embodiments, the heat pump device implementing the heat transfer process comprises at least one of: an input for receiving heated coolant liquid from the sump of the cooling column and / or process water from the reactor device; a conduit implementing a flash loop for feed water, wherein the flash loop includes a flash tank for generating steam from the feed water under a vacuum; a heat exchanger coupled to the input for transferring heat from the heated coolant liquid and / or the process water from the reactor device to the feed water in the flash loop; a degassing device for receiving demineralized water and generating degassed feed water; a further heat exchanger coupled to the input for transferring heat from the heated coolant liquid and / or the process water from the reactor device to the degassed feed water; at least one compressor device coupled to the flash tank for generating pressurized steam.

[0040] According to a third aspect, a use of a heat pump device for generating steam for heating purposes in an apparatus implemented to produce acetylene and synthesis gas by partial oxidation, wherein the heat pump device transfers excess heat from a reactor device and / or a cooling column to a steam generator, a steam reservoir and / or a steam grid of an industrial site.

[0041] The disclosed aspects of an acetylene production method and plant improves its energy efficiency and reduces the required energy for heating processes in acetylene production. Further, process steam is generated using waste heat recovered from the partial combustion and / or quenching process in acetylene production. The process steam can be employed during subsequent acetylene production steps as well as in other independent industrial chemical processes demanding steam.

[0042] Further possible implementations or alternative solutions of the invention also encompass combinations - that are not explicitly mentioned herein - of features described above or below in regard to the embodiments. The person skilled in the art may also add individual or isolated aspects and features to the most basic form of the invention. Further embodiments, features and advantages of the present invention will become apparent from the subsequent description and dependent claims, taken in conjunction with the accompanying drawings, in which:

[0043] Fig. 1 shows a schematic diagram of aspects of an acetylene plant relating to a cracked gas generation section,

[0044] Fig. 2 shows a schematic diagram of a first embodiment of a heat pump device; and

[0045] Fig. 3 shows a schematic diagram of a second embodiment of a heat pump device.

[0046] In the Figures, like reference numerals designate like or functionally equivalent elements, unless otherwise indicated.

[0047] Fig. 1 shows a part of an apparatus for producing acetylene, hence a section of a cracked gas generation of an acetylene plant 1. The acetylene plant 1 implements a Sachsse-Bartholome process where a hydrocarbon-containing gas, e.g. natural gas, LPG or ethane, is partially oxidized, and cracked gas with acetylene and synthesis gas is obtained and further processed.

[0048] The natural gas is partially oxidized by pure oxygen to carbon monoxide and hydrogen. The hydrogen produced is also partially oxidized to water. This provides the energy to build acetylene at temperatures of around 1 ,500 °C to 1 ,600 °C. Acetylene is a metastable molecule and continues to react quantitatively to produce soot at high temperatures. Hence, the cracked gas stream needs to be cooled down (quenched) rapidly in a quench process after the partial oxidation process.

[0049] In the diagram of Fig. 1 a reactor device 2 has an oxygen inlet 21 and a natural gas input 22 in the upper part or head. The lower part of the reactor device 2 comprises a reactor sump 27 with an output for coke 24 at the lowest position and process water output 25 above. The oxygen OX and the natural gas NG is preheated to temperatures about 600 °C and fed into the reactor device 2 through the inlet 21 and 22, respectively. The gas mixture runs downwards through a burner section 28 and is partially oxidized in a fireroom at temperatures above 1 ,500°C and pressures above ambient pressure (below 500 mbarg or about 1 ,2 bara). The resulting cracked gas contains mainly acetylene, hydrogen, carbon monoxide, and water, however also smaller amounts of carbon dioxide, remaining oxygen, nitrogen, methane, ethane, ethylene, allylene, vinyl acetylene, diacetylene and soot is contained.

[0050] Process water as quench water is injected below the fireroom through coolant input 23 at the upper of the lower part of the reactor device 2 in order to quench the cracked gas immediately within the reactor device 2. This quenching process occurs within 5 to 10 ms after partial oxidation using process water (or quench water) with a temperature of about 78 °C at 6 bara.

[0051] At the reactor sump 27 of the reactor device 2 coke and process or quench water accumulate. Coke is removed through the coke output 24. Separately, process or quench water PW at a temperature of about 90 °C is collected in the lower part of the reactor device 2 and removed at process water output 25.

[0052] The cracked gas CG from the reactor device 2 needs to be further cooled down though a cooling process. To this end, a cooling column 3 is provided. The cooling column 3, from bottom to top, has a cooling column sump 36 with a sump output 35, and a sump input 34. Above the cooling column sump 36 is cracked gas input 31 for receiving the cracked gas from the output 26 of the reactor device 2. The cracked gas CG has a temperature of about 90 °C at a pressure of 1.2 bara. In the head 37 of the cooling column 3, a coolant input 32 for coolant water CW at 33 °C and about 3 bara is provided. Further, above the coolant input 32, a cracked gas output 33 for the cracked gas cooled to about 30 °C to 35 °C at 1.2 bara is provided.

[0053] Hence, a cooling process on the cracked gas CG is performed for cooling the acetylene and the further gas components with cold process water CW as an input coolant liquid, wherein the cooling process is deployed in the cooling column 3. In the cooling process, the cracked gas CG from the reactor device 2 enters the cooling column 3 above the sump 36 and is in direct contact with the cool process water CW fed into the head 37 of the cooling column 3 through coolant input 32. At cracked gas output 33 the cooled acetylene and further gas components are provided for further processing steps.

[0054] In particular, a step of washing and stripping the cracked gas with its acetylene and other components is performed to obtain acetylene. A stripping process, is for example, performed in a stripping apparatus, e.g. a strip column (not shown), where an acetylene-containing solvent is conducted in a reverse flow with a strip gas. One obtains acetylene and an enriched solvent. N- Methyl-2-pyrrolidone (NMP) is used as solvent and is eventually heated using process stream of the plant 1. Heating the enriched NMP involves deploying vapor 61 retrieved from a steam reservoir 6.

[0055] A heat pump device 5 is configured to perform a heat transfer process HT for transferring heat from the collected heated coolant liquid from the quench column sump 36 into the steam reservoir 6 thereby generating chilled coolant liquid. The heat pump device 5 has an input 51 coupled to the sump output 35 for receiving the heated coolant liquid from the sump 36 of the cooling column 3. An output 52 of the heat pump device 5 is coupled to an input 41 of a heat exchanger 4.

[0056] The heat exchanger 4 has an input 41 and an output 42 and is coupled to a cooling water SCL circuit serving as a secondary cooling liquid. The cooling water SCL has a temperature of 28 °C at 2.8 bara. The input 41 of the heat exchanger 4 receives chilled coolant liquid, i.e. the process water from the cooling column sump 36 being subjected to the heat transfer process HT by the heat pump device 5. Through the heat pump device 5 waste heat is recovered and transferred to a steam reservoir 6 as explained below.

[0057] The steam reservoir 6 is a process steam network or grid 61 operating at various pressure and temperature levels. The steam network 61 may provide thermal energy to a plurality of technical facilities, even if not expressly depicted, in the acetylene plant 1. Additionally, or alternatively, the steam network 61 may supply heat to other technical devices at a chemical industrial site.

[0058] The output 42 of the heat exchanger is coupled to coolant input 32 of the cooling column 3. Thus, the generated chilled coolant liquid is processed by the heat exchanger 4 for generating input coolant liquid for the cooling column 3. A part of the water output from the heat exchanger 4 is discarded as wastewater WW.

[0059] Next, embodiments of heat pump devices implementing the heat transfer process HT indicated in Fig. 1 are described with reference to Figs. 2 and 3. In Fig. 2, a first embodiment of a heat pump device 5 is shown. The heat pump device 5 has a first input 51 and a first output 52. The first input 51 and output 51 are coupled to a medium from which heat is retrieved, e,g. the water accumulated in the cooling column sump 34. The input 51 and output 52 are coupled to a heat exchanger 53 of the heat pump device 5.

[0060] A flash loop 54 including a flash tank 56 is also coupled to the heat exchanger 53. Liquid circulating in the flash loop 54 is over-pressurized and receives heat through the heat exchanger 53. The flash tank 56 is operated to maintain a pressure such that the boiling temperature of the circulating liquid (pressurized water) in the flash loop 56 is lower, and the water evaporates in the flash tank 56 under expansion. Investigations of the applicant indicate that at least 1 to 3 wt% of the circulating water can be transferred into steam. Thus, process steam PS is generated that can be deployed by other devices in the acetylene plant 1 or elsewhere.

[0061] The heat pump device 5 has a second input 55 for feed water and a second output 57 for the generated steam PS. The feed water coupled to the feed water input 55 is demineralized water, and the steam PS withdrawn at the steam output 57 is suitable for use in an industrial process steam network.

[0062] In order to enhance the performance of the heat pump device 5, devices to implement the following process steps can be included: degassing demineralized water for generating feed water, e.g. deploying a membrane degassing device, a thermal and / or a vacuum degassing device; preheating the feed water, e.g. deploying a heat exchanger; and feeding the flash loop 54 with preheated feed water; compressing the generated steam to a predetermined steam pressure, e.g. by one or more compressor devices.

[0063] Fig. 3 shows a second embodiment of a heat pump device 50 comprising features and functions in addition to the first embodiment. Elements already depicted with respect to Fig. 2, i.e. the conduit implementing the flash loop 54 for feed water, the flash tank 56 in the flash loop 54 for generating steam from the feed water under a vacuum, and the heat exchanger 53 coupled to the input 51 for transferring heat from the heated coolant liquid to the feed water in the flash loop 54 have the same functions as in Fig. 2 and are not further elaborated on.

[0064] In the second embodiment the flash loop 54 comprises a flash loop pump 65 for circulating the water through the heat exchanger 53 and the flash tank 56.

[0065] The second embodiment of a heat pump device 50 further comprises a degassing device 66 for receiving demineralized water and generating degassed feed water, a further heat exchanger 67 coupled to the input 51 for transferring heat from the heated coolant liquid to the degassed feed water and obtaining preheated degassed feed water. Preheating the feed water can lead to a higher efficiency of the heat transfer process. A feed water tank 68 is provided for the preheated and degassed feed water, and a plurality of steam compressor devices 59, 60 are coupled to the flash tank 56 for generating pressurized steam and a vacuum in the flash tank 56. Vacuum is understood as a pressure level reducing the boiling temperature of the water in the flash tank below its input temperature after the heat exchanger 53.

[0066] In alternative configurations, one can dispense with degassing device 66 and combine the degassing process with feed water tank 68. The feed water received at the feed water input 55 is conducted though the degassing device 66 and the heat exchanger 67, wherein the heat exchanger 67 receives (hot) process water from the sump 36 of the quench column 3 (or alternatively, from the sump 27 of the reactor 2, not shown) and increases the temperature of the feed water to about 70 °C at 2.2 bara, which is collected in the feed water tank 68. A feed water pump 69 is provided to supply the feed water through appropriate conduits 58 to valves 62, 63, 64 acting as injection points into the flash loop (valve 64) and downstream of respective steam compressors 59, 60 (valves 62, 63). The injection point 64 for the flash loop 54 is located upstream of the flash pump 65 and downstream of the flash tank 56. Evaporated water, i.e. steam, is provided at a steam output of the flash tank 56. The steam has a temperature of 90 °C at 1 .5 bara.

[0067] One may contemplate of additional or alternative injection point, e.g. between heat exchanger 53 and flash tank 56.

[0068] In order to further pressurize the steam from the flash tank 56 a sequence of two steam compressors 59, 60 is provided downstream of the flash tank steam output 70 to stepwise increase the steam pressure. In order to obtain the desired pressure, a plurality of compressors can be deployed. The first compressor 59 raises the steam pressure from 1 .5 bara at its input to 3.4 bara at its output. The second compressor 60 raises the steam pressure further from 3.3 bara at its input to 7.0 bara at its output. Through the injection points 62 and 63 and controlled injection of feed water the desired steam pressure of the process steam PS available at the steam output 57 can be adjusted. The steam output 57 is coupled to an industrial steam network or grid (6, 61 , see Fig. 1).

[0069] According to the requirements of the industrial steam network, the number of compression stages and / or injection points can be set. For example, a third compressor may increase the steam pressure up to 14 bara, which is a widely used pressure level for process steam in acetylene plants.

[0070] Including a heat transfer process, as explained above, into an acetylene process flow and withdrawing heat at the specific locations for recovery lead to an improved acetylene production and improve energy efficiency. A carbon footprint of acetylene as primary material and of subsequent goods and materials requiring acetylene in their manufacture is reduced.

[0071] Although the present invention is explained in terms of specific embodiments, one may contemplate of modifications. It is understood that the heat pump devices may implement a heat transfer from process water collected from the sump of the reactor instead of the sump of the cooling column. The generated steam can be used directly within the acetylene production plant for heating purposes, e.g. in evaporators or reactors. In order to increase the efficiency of the heat transfer process, one may retrieve the hot process water from a plurality of reactors and / or cooling columns in an acetylene plant deploying multiple acetylene trains thereby increasing the mass and / or volume flow rate of hot medium provided to the heat exchanger in the heat pump arrangement. One may bend the process steam generated by the heat pump with conventionally generated process steam still improving the energy efficiency and carbon footprint of the acetylene process. The piping and instrumentation diagrams shown in the drawings are considered schematic and further engineering devices may be included to implement the desired acetylene and heat transfer processes. Further gas components in the cracked gas can be considered synthesis gas, i.e. a mixture of hydrogen and carbon monoxide in various ratios.

[0072] The depicted methods and apparatuses deploy an open-loop heat pump device. However, one may alternatively or additionally deploy heat pump devices with a specific heat-transfer medium.

[0073] Reference signs:

[0074] 1 apparatus for producing acetylene

[0075] 2 reactor device

[0076] 21 oxygen input

[0077] 22 natural gas input

[0078] 23 coolant input

[0079] 24 coke output for coke removal

[0080] 25 process water output

[0081] 26 cracked gas output

[0082] 27 reactor sump

[0083] 28 burner section

[0084] 3 cracked gas cooling column

[0085] 31 cracked gas input

[0086] 32 coolant input

[0087] 33 cracked gas output

[0088] 34 sump

[0089] 35 sump output

[0090] 36 cooling column sump

[0091] 37 cooling column head

[0092] 4 heat exchanger

[0093] 41 input 42 output

[0094] 5, 50 heat pump device

[0095] 51 input

[0096] 52 output

[0097] 53 heat exchanger

[0098] 54 flash loop (over pressurized)

[0099] 55 feed water input

[0100] 56 flash tank / steam generator

[0101] 57 steam output

[0102] 58 feed water

[0103] 59, 60 steam compressor

[0104] 6 steam reservoir

[0105] 61 steam grid

[0106] 62, 63, 64 feed water injection points

[0107] 65 flash loop pump

[0108] 66 degassing device

[0109] 67 heat exchanger

[0110] 68 feed water tank

[0111] 69 feed water pump

[0112] 70 steam output

[0113] CG cracked gas

[0114] CW coolant water

[0115] HT heat transfer

[0116] NG natural gas

[0117] OX oxygen

[0118] PS process steam

[0119] PW process water

[0120] SCL secondary cooling liquid

[0121] SW sump liquid

[0122] WW waste water

Claims

Claims1. A method for producing acetylene and synthesis gas by partial oxidation comprising: in a reactor device (2), generating a quenched cracked gas (CG) comprising acetylene and further gas components, and collecting process water (PW) used for the quench process in the reactor device (2); performing a cooling process on the cracked gas (CG) for cooling the acetylene and the further gas components with an input coolant liquid, said cooling process being deployed in a cooling column (3); collecting heated coolant liquid from a sump (35) of the cooling column (3); performing a heat transfer process (HT) for transferring heat from the collected heated coolant liquid into a steam reservoir (6) thereby generating chilled coolant liquid, and / or performing a heat transfer process (HT) for transferring heat from the collected process liquid (PW) into the steam reservoir (6); processing the generated chilled coolant liquid for generating input coolant liquid for the cooling column (3); and washing and stripping the cracked gas for obtaining acetylene.

2. The method of claim 1 , wherein processing the generated chilled coolant liquid includes: passing the generated chilled coolant liquid through a heat exchanger (4) for generating the input coolant liquid for the cooling column (3), said heat exchanger (4) deploying a secondary coolant liquid (SOL).

3. The method of claim 1 or 2, wherein the heat transfer process (HT) is deployed in a heat pump device (5), in particular an open loop heat pump.

4. The method of any one of claims 1 - 3, wherein the heat transfer process (HT) comprises: evaporating feed water in a vacuum atmosphere for generating steam.

5. The method of any one of claims 1 - 4, wherein the heat transfer process (HT) comprises the steps of: transferring heat from the collected heated coolant liquid and / or the collected process liquid (PW) into a flash loop (54) containing feed water, said feed water acquiring a flash loop temperature; in the flash loop (54), circulating the feed water under a flash loop pressure such that the flash loop temperature is lower than the boiling temperature of the feed water;in a flash tank (56) coupled to the flash loop (54), evaporating feed water by decreasing a pressure in the flash tank (56) such that flash loop temperature is at least boiling temperature of the feed water in the flash tank (56) thereby generating steam.

6. The method of claim 4 or 5, further comprising: compressing the generated steam through one or more compressor devices (59, 60) to a predetermined steam pressure.

7. The method of any one of claims 4 - 6, further comprising at least one of the steps of: degassing demineralized water for generating feed water, in particular deploying a membrane degassing device, a thermal and / or a vacuum degassing device; preheating the feed water deploying a heat exchanger (67); and feeding the flash loop (54) with preheated feed water.

8. The method of any one of claims 1 - 7, wherein a temperature of the collected heated coolant liquid and / or the collected process liquid (PW) is between 70 °C and 90 °C, preferably between 75 °C and 85 °C, even more preferred between 78 °C and 80 °C.

9. The method of any one of claims 1 - 8, further comprising: stripping an acetylene-containing solvent in a reverse flow with a strip gas, for obtaining acetylene and enriched solvent; and heating the enriched solvent deploying vapor retrieved from the steam reservoir (6).

10. The method of any one of claims 1 - 9, operating a plurality of reactor devices and / or quenching devices in parallel for executing the method steps of any one of claims 1 - 9 in parallel, wherein the heat transfer process (HT) for transferring heat from the collected heated coolant liquid and / or for transferring heat from the collected process liquid (PW) is deployed in one single heat pump device for generating steam for a steam reservoir (6), in particular for an industrial steam network.

11. An apparatus (1) for producing acetylene and synthesis gas by partial oxidation comprising: a reactor device (2) configured to generate a cracked gas (CG) comprising acetylene and further gas components, the reactor device (2) further configured to quench the hot cracked gas and to collect process liquid (PW) from the quench process; a cooling column (3) configured to cool the acetylene and the further gas components with an input coolant liquid; and17 a heat pump device (5) communicatively coupled to a sump of the cooling column (3) for collecting heated coolant liquid, and / or being communicatively coupled to the reactor device (2) for collecting process liquid (PW), the heat pump device (5) being implemented to transfer heat (HT) from heated coolant liquid and / or the process liquid (PW) into a steam reservoir (6), wherein the heat pump device (5) is provided downstream of the cooling column (3) and / or the reactor device (2).

12. The apparatus of claim 11 , further comprising a heat exchanger (4) having an input (41) and an output (42), the input (41) being coupled to a sump (35) of the cooling column (3) and the output (42) being coupled to a head (32) of the cooling column (3), wherein the heat exchanger (4) is implemented to cool heated coolant liquid from the sump (35) and / or process liquid (PW) from the reactor device (2) deploying a secondary coolant liquid (SCL), and the heat pump device (5, 50) is provided upstream of the heat exchanger (4).

13. The apparatus of claim 12, wherein the heat pump device (5, 50) comprises at least one of: an input (51) for receiving heated coolant liquid from the sump of the cooling column (3) and / or process liquid (PW) from the reactor device (2); a conduit implementing a flash loop (54) for feed water, wherein the flash loop (54) includes a flash tank (56) for generating steam from the feed water under a vacuum; a heat exchanger (53) coupled to the input (51) for transferring heat from the heated coolant liquid and / or the process liquid (PW) from the reactor device (2) to the feed water in the flash loop (54); a degassing device (66) for receiving demineralized water and generating degassed feed water; a further heat exchanger (67) coupled to the input (51) for transferring heat from the heated coolant liquid and / or the process liquid (PW) from the reactor device (2) to the degassed feed water; at least one compressor device (59, 60) coupled to the flash tank (56) for generating pressurized steam.

14. The apparatus of any one of claims 1 - 13, wherein the apparatus is configured to carry out the method of any one of claims 1 - 10.

15. Use of a heat pump device (5, 50) for generating steam for heating purposes in an apparatus (1) implemented to produce acetylene and synthesis gas by partial oxidation, wherein the18 heat pump device (5) transfers excess heat from a reactor device (2) and / or a cooling column(3) to a steam generator (56), a steam reservoir (6) and / or a steam grid (61) of an industrial site.

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