CN114518016A - Carbon dioxide capturing, liquefying and recycling device and method - Google Patents

Carbon dioxide capturing, liquefying and recycling device and method Download PDF

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Publication number
CN114518016A
CN114518016A CN202011312939.3A CN202011312939A CN114518016A CN 114518016 A CN114518016 A CN 114518016A CN 202011312939 A CN202011312939 A CN 202011312939A CN 114518016 A CN114518016 A CN 114518016A
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pipeline
gas
carbon dioxide
outlet
inlet
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CN202011312939.3A
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Chinese (zh)
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杨晓东
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Nisa Xi'an Energy Technology Co ltd
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Nisa Xi'an Energy Technology Co ltd
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    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2260/00—Coupling of processes or apparatus to other units; Integrated schemes
    • F25J2260/02—Integration in an installation for exchanging heat, e.g. for waste heat recovery
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2260/00—Coupling of processes or apparatus to other units; Integrated schemes
    • F25J2260/80—Integration in an installation using carbon dioxide, e.g. for EOR, sequestration, refrigeration etc.
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/12—External refrigeration with liquid vaporising loop
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/90—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration

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  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Carbon And Carbon Compounds (AREA)
  • Separation By Low-Temperature Treatments (AREA)

Abstract

The invention discloses a carbon dioxide capturing, liquefying and recovering device which comprises a pretreatment unit, a compression unit, a drying unit and a liquefying and recovering unit, wherein the pretreatment unit is used for collecting carbon dioxide; the pretreatment unit comprises a desulfurizing tower and a precooling separator and is used for carrying out desulfurization and dehydration pretreatment on the acid gas from the LNG factory; the compression unit comprises a carbon dioxide compressor, an air cooler and a gas-liquid separator and is used for pressurizing the pretreated acid gas; the drying unit comprises a drying tower for deeply drying the compressed acid gas; the liquefaction recovery unit mainly comprises a heat exchange device for liquefying CO2. The invention also discloses CO based on the device2A method for recovering the trapped liquid. The invention depends on the components and CO of the acid gas discharged by the LNG factory2Physical and chemical properties of (1), design of CO2The capture liquefaction recovery device captures the originally emptied acid gas to prepare liquid CO2Thereby effectively recovering CO discharged from plants2In reducing greenhouse gasesThe economic benefit of the factory is improved while the body is discharged.

Description

Carbon dioxide capture liquefaction recovery device and method
Technical Field
The present invention relates to the field of Liquefied Natural Gas (LNG), and more particularly, to a method and an apparatus for preparing liquid carbon dioxide from acid gas (hereinafter, referred to as acid gas) discharged from an Acid Gas Removal Unit (AGRU) of an LNG plant.
Background
Typically, pipeline natural gas contains about 1% to 3% carbon dioxide gas. Since Liquefied Natural Gas (LNG) is a cryogenic liquid, CO, at about-162 deg.C2Even at very low partial pressures (typically within 50ppm of pretreatment requirements for LNG plants), freezing and plugging can occur at the low temperature section of the plant, and therefore LNG plants are equipped with an Acid Gas Removal Unit (AGRU) in the natural gas pretreatment section to remove acid gases such as carbon dioxide from the natural gas. The AGRU unitAlcohol amine solutions (currently, formulations mainly comprising Methyldiethanolamine (MDEA) are widely used in China) are generally used for reacting with acid gases such as carbon dioxide to remove the acid gases. The reaction is carried out in an absorption tower of the AGRU, then the rich solution is heated and regenerated in a stripping tower, and the gas at the top of the stripping tower is released to the atmosphere after being cooled.
This process of venting AGRU unit stripper overhead gases directly to the atmosphere results in wasted resources and greenhouse gas (GHG) emissions. Taking a certain 100-ten-thousand-square/day LNG device in Shaanxi of China as an example, the tower top gas of the stripping tower of the AGRU unit of the LNG plant is finally discharged through the separator. The material balance is adopted, and the acidic vent gas state of the plant stripping tower is as follows: temperature 55 deg.C, pressure 160 Kpa; the flow rate is 98.86kmol/hr, wherein, CO289.77%, water 9.96%, C10.2713％，C2 9.1ppm，C3 0.34ppm，N23.95 ppm. If the sour vent gas at the top of the stripper can be captured for recovery, there is 88.75kmol/hr of CO in total2Can be recycled, and the yield is 3904kg/hr, which is about 3.1 ten thousand tons/year. And CO2Is an important chemical raw material, and a large amount of CO is needed in the industries of food, light industry, metallurgy, chemical industry and the like2A gas; the group to which the plant belongs is a large-scale national oil exploitation enterprise, the oil and gas exploitation yield can be improved by applying liquid carbon dioxide to oil and gas field fracturing, and the yield increase and the efficiency increase of the oil and gas field are facilitated, namely the group has a large amount of liquid carbon dioxide demand, so that the prior process for directly emptying the acid gas of the AGRU unit has obvious defects.
Disclosure of Invention
One of the technical problems to be solved by the invention is to provide a device for capturing, liquefying and recovering carbon dioxide by acid gas discharged by an AGRU unit of an LNG plant, which can obviously improve the economic benefit and the social benefit of the LNG plant.
In order to solve the above-described problems, the carbon dioxide capturing liquefaction recovery apparatus of the present invention includes: the device comprises a pretreatment unit, a compression unit, a drying unit and a liquefaction recovery unit; wherein the content of the first and second substances,
the pretreatment unit comprises a desulfurizing tower and a precooling separator; the inlet of the desulfurizing tower is connected with an acid gas outlet at the top of a stripping tower of an acid gas removal unit of an LNG factory through a pipeline, and the outlet of the desulfurizing tower is connected with the inlet of the precooling separator through a pipeline;
the compression unit is arranged behind the pretreatment unit and comprises a carbon dioxide compressor, an air cooler and a gas-liquid separator; the compression stage number of the carbon dioxide compressor is more than or equal to 1, the inlet of the first-stage compression is connected with the outlet of the precooling separator of the pretreatment unit through a pipeline, an air cooler and a gas-liquid separator are respectively and sequentially arranged after each stage of compression, the inlet of the air cooler is connected with the outlet of the first-stage compression through a pipeline, the outlet of the air cooler is connected with the inlet of the gas-liquid separator through a pipeline, the outlet of the gas-liquid separator is connected with the inlet of the next-stage compression through a pipeline, and the outlet of the last-stage gas-liquid separator is communicated with the drying unit through a pipeline;
the drying unit is arranged behind the compression unit and comprises more than one drying tower; a carbon dioxide inlet of the drying tower is connected with an outlet of the last stage of gas-liquid separator of the compression unit through a pipeline; a carbon dioxide outlet of the drying tower leads to the liquefaction recovery unit through a pipeline;
the liquefaction recovery unit is arranged behind the drying unit and comprises heat exchange equipment and a liquid carbon dioxide storage tank; a carbon dioxide inlet of the heat exchange equipment is connected with an outlet of the drying tower through a pipeline; a carbon dioxide outlet of the heat exchange device is communicated with an inlet of the liquid carbon dioxide storage tank; and a liquid carbon dioxide product pipeline is arranged at an outlet at the bottom of the liquid carbon dioxide storage tank.
The inlet of the desulfurizing tower is generally arranged at the bottom of the desulfurizing tower, and the outlet of the desulfurizing tower is generally arranged at the top of the desulfurizing tower; the inlet of the pre-cooling separator is generally disposed at the top of the pre-cooling separator, and the outlet is generally disposed at the upper portion of the pre-cooling separator.
Preferably, a pre-cooling heat exchanger is arranged on a pipeline between the desulfurizing tower and the pre-cooling separator and used for cooling the desulfurized acid gas.
Preferably, a flow meter can be arranged on the inlet pipeline of the desulfurization tower and used for measuring the flow of the acid gas from the tower top of the AGRU unit stripping tower of the LNG plant.
The carbon dioxide compressor may be a single-stage compressor or a multi-stage compression (the two-stage compression is also a multi-stage compression) machine, and preferably a three-stage compressor is used.
The inlet of the gas-liquid separator of the compression unit is generally disposed at the upper portion of the gas-liquid separator, and the outlet is generally disposed at the top of the gas-liquid separator.
The carbon dioxide inlet of the drying tower is generally arranged at the upper part of the drying tower, and the carbon dioxide outlet is generally arranged at the bottom of the drying tower. The regeneration gas inlet of the drying tower is generally arranged at the bottom of the drying tower, and the regeneration gas outlet is generally arranged at the upper part of the drying tower.
Preferably, the drying unit further comprises a regeneration gas cooler and a regeneration gas-liquid separator. The regeneration gas inlet of the drying tower is connected with a regeneration gas inlet pipeline from an LNG plant, the regeneration gas outlet of the drying tower is connected with the inlet of the regeneration gas cooler through a pipeline, the outlet of the regeneration gas cooler is connected with the inlet of the regeneration gas-liquid separator (generally arranged on the upper part of the regeneration gas-liquid separator) through a pipeline, and the outlet of the regeneration gas-liquid separator (generally arranged on the top of the regeneration gas-liquid separator) is connected with a regeneration gas return pipeline leading to a regeneration gas unit of the LNG plant through a pipeline.
The number of the drying towers is preferably 2, the 2 drying towers preferably adopt an alternate working mode, and when one tower works on line, the other tower is regenerated. The drying tower can be filled with molecular sieve drying agent.
Preferably, the liquefaction recovery unit further comprises a refrigerant compressor inlet separator, a refrigerant compressor and an air cooler; a refrigerant outlet of the heat exchange equipment is connected with an inlet of the refrigerant compressor inlet separator through a pipeline; the refrigerant compressor has the compression stage number more than or equal to 1, the inlet of the first-stage compression is connected with the outlet of the inlet separator of the refrigerant compressor through a pipeline, an air cooler is arranged after each stage of compression, the inlet of the air cooler is connected with the outlet of the first-stage compression through a pipeline, the outlet of the air cooler is connected with the inlet of the next-stage compression through a pipeline, and the outlet of the last-stage air cooler is connected with the refrigerant inlet of the heat exchange equipment through a pipeline.
The inlet of the refrigerant compressor inlet separator is generally disposed at an upper portion of the refrigerant compressor inlet separator, and the outlet is generally disposed at a top portion of the refrigerant compressor inlet separator. The inlet of the liquid carbon dioxide storage tank is generally arranged at the bottom of the liquid carbon dioxide storage tank, and a carbon dioxide throttle valve is generally arranged on a pipeline in front of the inlet and used for adjusting the flow of the liquid carbon dioxide to the storage pressure of the liquid carbon dioxide.
The refrigerant compressor preferably employs multi-stage compression for improved efficiency, such as a two-stage compressor.
The heat exchange equipment can be a carbon dioxide cooler or a cold box and the like.
A shell and tube heat exchanger may be employed in the carbon dioxide cooler. A refrigerant throttle valve is generally installed on a pipeline between a refrigerant inlet of the carbon dioxide cooler and an outlet of the last-stage air cooler of the liquefaction recovery unit and used for adjusting the flow of the refrigerant.
The cold box is usually an expanded perlite cold insulation cold box, and a multi-flow channel heat exchanger, preferably a plate-fin heat exchanger, is arranged in the cold box. The carbon dioxide inlet, the refrigerant inlet and the refrigerant outlet of the cold box are typically disposed at the top of the cold box. The carbon dioxide inlet of the cold box is typically located at the bottom of the cold box. In addition, the bottom of the cold box is also provided with a high-pressure refrigerant outlet and a low-pressure refrigerant return cold box inlet, the high-pressure refrigerant outlet and the low-pressure refrigerant return cold box inlet are connected through a pipeline, and a refrigerant throttle valve is arranged on the pipeline.
According to the purity requirement of the liquid carbon dioxide product (such as food-grade carbon dioxide product) which needs to be prepared, a low-temperature rectifying tower can be further arranged on a pipeline between the cold box and the carbon dioxide throttling valve so as to rectify and purify the liquid carbon dioxide. At this time, carbon dioxide outlets may be provided at the middle and bottom of the cold box, respectively. The carbon dioxide outlet in the middle of the cold box is connected with the inlet in the middle of the low-temperature rectifying tower through a pipeline, and a throttle valve can be arranged on the pipeline to adjust the flow of the carbon dioxide. The carbon dioxide outlet at the bottom of the cold box is connected with the inlet at the top of the low-temperature rectifying tower through a pipeline. The top outlet of the low-temperature rectifying tower is provided with a non-condensable gas pipeline, and the bottom outlet of the low-temperature rectifying tower is communicated to a liquid carbon dioxide storage tank through a carbon dioxide throttle valve. The lower part of the low-temperature rectifying tower is provided with a reboiler for controlling the purity of the liquid carbon dioxide product. The heat source of the reboiler can be considered as being integrated with the LNG plant, the heat source from the LNG plant is received through the heat source conveying pipeline, and the used heat source is returned to the LNG plant through the heat source return LNG plant pipeline; the heat source may also be self-contained, such as by use of an electric heater.
The invention also provides a process method for capturing, liquefying and recovering carbon dioxide from acid gas discharged by an AGRU unit of an LNG plant by using the device and preparing liquid carbon dioxide products with different purities according to requirements.
In order to solve the above technical problems, the method for capturing, liquefying and recovering carbon dioxide of the present invention comprises the steps of:
1) pretreatment: carrying out desulfurization and dehydration pretreatment on acid gas from the top of a stripping tower of an acid gas removal unit of an LNG plant;
2) compression: the acid gas after pretreatment is compressed by more than one stage, and cooling and gas-liquid separation and dehydration are respectively carried out after each stage of compression;
3) and (3) drying: drying the compressed acid gas in a drying tower;
4) liquefaction and recovery: and (4) sending the acid gas dried in the step 3) into heat exchange equipment to exchange heat with a refrigerant, liquefying the acid gas into liquid carbon dioxide, and sending the liquid carbon dioxide into a liquid carbon dioxide storage tank to store.
Preferably, in the step 1), after the desulfurization and before the dehydration, the desulfurized sour gas is cooled to normal temperature.
Preferably, in the step 2), the acid gas after pretreatment is subjected to three-stage compression, the acid gas pressure is increased to medium pressure of 25-30 bar, and the temperature is cooled to normal temperature of 25-40 ℃.
In the step 3), the dried natural gas or the evaporated gas after the treatment of the LNG plant is preferably used as the source of the regenerated gas for the regeneration of the drying tower, and the heated regenerated gas is cooled and dehydrated and then returned to the LNG plant.
In the above step 4), the refrigerant circulation process is preferably: the refrigerant flows out of the heat exchange equipment, is subjected to gas-liquid separation, and is compressed and cooled by more than one stage, and then flows back to the heat exchanger. The compression of the refrigerant is preferably a multistage compression, and more preferably a two-stage compression.
Preferably, step 4) above, before the liquid carbon dioxide enters the liquid carbon dioxide storage tank for storage, a rectification step may be further included to further purify the liquid carbon dioxide. After the acid gas is cooled to an intermediate temperature in the heat exchange equipment, part of the acid gas can be pumped out from the middle part of the heat exchange equipment for low-temperature rectification and purification; and the other part of the acid gas is continuously cooled to a lower temperature, and leaves from the bottom of the heat exchange device to be used as a cold source for low-temperature rectification.
The method is characterized in that a carbon dioxide capturing and liquefying recovery device is designed according to the actual components (mainly carbon dioxide) of the acid gas discharged from the top of the AGRU stripping tower of the LNG plant and the physicochemical characteristics of the carbon dioxide, the acid gas at the top of the stripping tower is captured, purified by desulfurization, drying and the like, and then compressed, cooled and rectified (only used for food-grade high-purity CO)2Recovery), etc., to effectively capture and recover the carbon dioxide discharged by the LNG plant. Compared with the treatment technology of the top gas of the stripping tower of the acid gas removal unit of the existing LNG factory, the carbon dioxide capturing, liquefying and recovering device and the method have the following advantages and beneficial effects:
1. the invention can effectively recover CO in the exhaust gas of the liquefied gas stripping tower under the condition of not influencing the normal production of the original natural gas liquefaction device2And the liquid carbon dioxide is a byproduct, so that the economic benefit of a factory can be improved on one hand, the emission of greenhouse effect gases can be reduced on the other hand, and the method is green and environment-friendly and has obvious social benefit.
2. CO of the invention2The energy and material balance of the purification and liquefaction process can be integrally coupled with the original LNG factory, so that the preparation of high-purity CO can be obviously improved2Economy of (and overall energy utilization efficiency of) (comparable to conventional)High purity liquid CO of2The energy of the preparation process is saved by more than 10 percent), and the energy efficiency of the original LNG plant is improved.
3. The device of the invention adopts full-modular manufacturing and installation and is arranged nearby the AGRU unit in the original LNG device, thereby not only saving land but also having low investment (CO)2The investment of the gathering liquefaction recovery device can be recovered within 1 year), the field installation and the operation are simple, and the running economy and the CO of the existing LNG device can be obviously improved2The preparation is economical and has obvious economic benefit.
4. The invention can be based on liquid CO2The optimal process arrangement is selected for different downstream applications of the product, i.e. both high purity food grade CO can be arranged2Liquefaction purification process, or simplified common purity CO2(e.g., CO for oil and gas field flooding gas production2) And (4) a liquefaction and purification process. The invention prepares high-purity liquefied CO by an innovative rectification method2Simple and efficient process, and high purity liquid CO compared with conventional high purity liquid CO2The investment of the preparation process is saved by more than 20 percent.
Drawings
FIG. 1 is a schematic representation of an example 1 of the present invention for the production of liquid CO for an oil and gas field from LNG plant AGRU stripper overhead sour gas2Fractured CO2The device and process flow diagram of (1);
FIG. 2 is a schematic diagram of an example 2 of the present invention for producing high purity (food grade) liquid CO from LNG plant AGRU stripper overhead sour gas2The apparatus and process flow diagram of (rectification section using heat source from LNG plant);
FIG. 3 is a schematic representation of the preparation of high purity (food grade) liquid CO from LNG plant AGRU stripper overhead sour gas in accordance with example 2 of the present invention2The device and the process flow are shown schematically (the rectifying section adopts a self-heating mode).
The reference numerals in the figures are illustrated as follows:
01：CO2raw material pipeline
02: flow meter
03: desulfurizing tower inlet pipeline
04: desulfurizing tower
05: outlet pipeline of desulfurizing tower
06: precooling heat exchanger
07: precooling heat exchanger outlet pipeline
08: precooling separator
09: precooling separator outlet pipeline
10：CO2Compressor one-stage compression
11：CO2Compressor first-stage compression outlet pipeline
12: first air cooler
13: first air cooler outlet pipeline
14: first-stage separator
15: first-stage separator outlet pipeline
16：CO2Two-stage compression of compressor
17：CO2Two-stage compression outlet pipeline of compressor
18: second air cooler
19: second air cooler outlet pipeline
20: two-stage separator
21: secondary separator outlet pipeline
22：CO2Three-stage compression of compressor
23：CO2Three-stage compression outlet pipeline of compressor
24: third air cooler
25: third air cooler outlet pipeline
26: three-stage separator
27: three-stage separator outlet pipeline
28: first drying tower
29: second drying tower
30: dry outlet pipe
31：CO2Cooling device
32: low temperature CO2Pipeline
33：CO2Throttle valve
34：CO2Throttling back pipeline
35: liquid CO2Storage tank
36: BOG pipeline
37: liquid CO2Product pipeline
38: refrigerant return pipeline
39: refrigerant compressor inlet separator
40: separator outlet pipe
41: one-stage compression of refrigerant compressor
42: first-stage compression outlet pipeline of refrigerant compressor
43: fourth air cooler
44: fourth air cooler outlet pipeline
45: two-stage compression of refrigerant compressor
46: secondary compression outlet pipeline of refrigerant compressor
47: fifth air cooler
48: fifth air cooler outlet pipe
49: refrigerant throttle valve
50: cryogen throttle back pipeline
51: regenerated gas pipeline
52: regenerated gas return pipeline
53: first program control valve
54: second program control valve
55: third program control valve
56: fourth program control valve
57: fifth program control valve
58: sixth program control valve
59: seventh program control valve
60: eighth program control valve
61: ninth program control valve
62: tenth program control valve
63: eleventh program control valve
64: twelfth program control valve
65: regenerated gas cooler
66: regeneration gas-liquid separator
67: cold box
68: refrigerant return pipeline
69: refrigerant throttle valve
70: high-pressure refrigerant outlet box pipeline
71：CO2Precooling pipeline
72: flow regulating valve
73: cold box CO2Outlet duct
74: low-temperature rectifying tower
75: high pressure liquid CO2Pipeline
76：CO2Throttle valve
77: low pressure liquid CO2Pipeline
78: noncondensable gas pipeline
79: heat source pipeline from LNG plant
80: temperature control valve
81: reboiler device
82: heat source pipeline returning to LNG plant
83: electric heater
84: thirteenth program control valve
Detailed Description
In order to more specifically understand the technical content, characteristics and effects of the present invention, the technical solution of the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.
Example 1 preparation of liquid CO for oil and gas field from LNG plant AGRU stripper overhead sour gas2Fractured CO2
The apparatus for capturing, liquefying and recovering carbon dioxide from acid gas removed from AGRU unit of LNG plant according to the present embodiment has a structure as shown in fig. 1, and mainly includes: the device comprises a pretreatment unit, a compression unit, a drying unit and a liquefaction recovery unit. Wherein:
the pretreatment unit mainly comprises a flowmeter 02, a desulfurizing tower 04, a precooling heat exchanger 06 and a precooling separator 08. The flowmeter 02 is mounted in the CO2Between the feed line 01 and the inlet line 03 of the desulfurization tower, the flow of the acid gas from the top of the stripping tower of the AGRU unit of the LNG plant is measured. The desulfurizing tower 04 is filled with a desulfurizing agent capable of reacting with hydrogen sulfide and used for removing trace H possibly contained in the acid gas2And (4) S gas. The precooling heat exchanger 06 is arranged on the outlet pipeline 05 of the desulfurizing tower and is used for desulfurizingCooling the acid gas to normal temperature. Precooling heat exchanger outlet conduit 07 is connected to the top inlet of precooling separator 08. Pre-cooling separator 08 is used to remove the free water condensed on the desulfurized and pre-cooled acid gas.
The compression unit is arranged after the pretreatment unit and comprises CO2Compressor, air cooler and vapour and liquid separator. CO 22Compressor for compressing CO2Gas, make CO2Pressurizing the gas; air cooler for reducing CO2The temperature of the gas; the gas-liquid separator is used for removing CO after compression and cooling2Free water condensed in the gas. CO 22The compression stages of the compressor can be selected from single-stage compression or multi-stage compression (for example, two-stage compression, three-stage compression, or even more stages of compression) according to specific situations, and after each stage of compression, an air cooler and a gas-liquid separator are respectively arranged (namely, the number of the air cooler and the gas-liquid separator corresponds to the number of the compression stages). CO used in this example2The compressor is three-stage compression. CO 22The inlet of the first-stage compression 10 of the compressor is connected with the outlet pipeline 09 of the precooling separator, CO2A first-stage compression outlet pipeline 11 of the compressor is connected with a first air cooler 12, an outlet pipeline 13 of the first air cooler is connected with an inlet of a first-stage separator 14, and an outlet pipeline 15 of the first-stage separator is connected with CO2The compressor has a two-stage compression 16 inlet. Two-stage and three-stage compression refer to one-stage compression, respectively at CO2After the compressor is compressed in two stages 16, a second air cooler 18 and a second separator 20 are arranged in sequence, and CO is treated2After the compressor three-stage compression 22, a third air cooler 24 and a three-stage separator 26 are sequentially arranged, as shown in fig. 1.
The drying unit is arranged behind the compression unit and mainly comprises a drying tower, a regeneration gas cooler 65, a regeneration gas-liquid separator 66 and a plurality of program control valves. The present embodiment is configured with double drying towers, i.e., a first drying tower 28 and a second drying tower 29. The carbon dioxide inlets of the two drying towers are arranged at the top of the drying towers and are respectively connected with the outlet pipelines 27 of the three-stage separators of the compression unit; the carbon dioxide outlet is arranged at the bottom of the drying tower and is respectively connected with a drying outlet pipeline 30; the regeneration gas inlet is arranged at the bottom of the drying tower and is respectively connected with a regeneration gas inlet pipeline 51; the regenerated gas outlet is arranged atThe top of the drying tower is connected with the inlet of the regeneration gas cooler 65. Program control valves are arranged on the inlet pipeline and the outlet pipeline of the drying tower. The drying tower is filled with molecular sieve drying agent for treating CO treated by the compression unit2The gas is deeply dried. The two drying towers work in a mode of switching one-tower work and one-tower regeneration, work in a staggered time period with a molecular sieve dryer of an LNG plant, and share a regenerated gas heater. A regeneration gas cooler 65 and a regeneration gas-liquid separator 66 are arranged in front of the regeneration gas return pipeline 52, an outlet of the regeneration gas cooler 65 is connected with an inlet of the regeneration gas-liquid separator 66, and an outlet of the regeneration gas-liquid separator 66 is connected with the regeneration gas return pipeline 52. The regeneration gas cooler 65 is used to cool the regeneration gas. The regeneration gas-liquid separator 66 is used to remove free water from the regeneration gas cooled by the regeneration gas cooler 65.
The liquefaction recovery unit is arranged after the drying unit and mainly comprises CO2Chiller 31, refrigerant compressor inlet separator 39, refrigerant compressor, air cooler, refrigerant throttle 49, and liquid CO2A storage tank 35. In this example, CO2The cooler 31 is a shell-and-tube heat exchanger. CO 22CO of cooler 312The inlet is connected with a dry outlet pipeline 30, and the outlet is connected with liquid CO2An inlet of the storage tank 35 for cooling and liquefying CO from the top of the first drying tower 28 and the second drying tower 292A gas. CO 22A refrigerant return line 38 at the bottom of the cooler 31 connects to the inlet of a refrigerant compressor inlet separator 39. Refrigerant compressor inlet separator 39 for separation of CO2The refrigerant flowing back from the cooler 31, which is harmless to the environment, removes a small amount of liquid impurities that may exist in the returned refrigerant (under normal working conditions, the refrigerant should be in a full gas phase, but in order to ensure that the refrigerant entering the refrigerant compressor is in a full gas phase and does not contain liquid impurities, a gas-liquid separator is arranged at the inlet of the refrigerant compressor). The refrigerant compressor is used for compressing refrigerant, and the embodiment adopts two-stage compression, and comprises a refrigerant compressor one-stage compression 41 and a refrigerant compressor two-stage compression 45, each stage of compression is provided with an air cooler for reducing the temperature of the refrigerant, and the air coolers are a fourth air cooler 43 and a fifth air cooler 47 respectively, as shown in fig. 1The inlet of the first-stage compression 41 of the refrigerant compressor is connected with the outlet pipeline 40 of the separator, and the outlet of the first-stage compression 41 of the refrigerant compressor is connected with the inlet of the fourth air cooler 43; the inlet of the secondary compression 45 of the refrigerant compressor is connected with the outlet pipeline 44 of the fourth air cooler, and the outlet of the secondary compression 45 of the refrigerant compressor is connected with the inlet of the fifth air cooler 47. The fifth air cooler outlet pipe 48 is connected to the CO via a refrigerant throttle 492A refrigerant inlet of the cooler 31. The refrigerant throttle valve 49 is used to adjust the refrigerant flow rate. Liquid CO2The storage tank 35 is used for storing liquefied CO2And (5) producing the product. Liquid CO2The inlet of the storage tank 35 is connected with CO2CO of cooler 312And (7) an outlet. Liquid CO2Storage tank 35 and CO2CO is installed in the connection line between the coolers 312A throttle valve 33 for liquefying and subcooling the CO2Throttling to liquid CO2The pressure is stored. Liquid CO2The bottom outlet of the storage tank 35 is connected with liquid CO2A product line 37 and a top outlet connected to the BOG line 36.
The acid gas removed from the tower top of the LNG plant AGRU stripping tower by using the device is captured, liquefied and recycled for the liquid CO in the oil and gas field2Fractured CO2The specific process flow of (A) is described in detail.
As shown in FIG. 1, sour gas from the overhead of the AGRU stripper of the LNG plant is subjected to CO2The raw material enters a desulfurizing tower 04 after passing through a raw material pipeline 01 and a flowmeter 02, and trace H possibly contained in the acid gas is removed2And (4) S gas. The desulfurized sour gas enters a precooling heat exchanger 06 to be cooled to normal temperature (the sour gas discharged from the top of the AGRU stripping tower is generally higher in temperature and therefore needs precooling), and then enters a precooling separator 08 to remove the condensed free water.
Pre-purified CO from the upper end of pre-cooling separator 082The acid gas as the main component is subjected to three-stage compression and temperature reduction by a carbon dioxide compressor, condensed free water is removed (at the moment, the gas pressure is increased to about 25-30 bar at the medium pressure, the temperature is cooled to the normal temperature of 25-40 ℃), and the acid gas enters a first drying tower 28 or a second drying tower 29 through an outlet pipeline 27 of a three-stage separator for deep drying. Two drying towers adopt a switching mode of one-tower operation and one-tower regeneration, and the two drying towers and a regeneration gas unit of an LNG factory integrally consider energy and substancesThe material matching, working with the molecular sieve dryer of the LNG plant in 'wrong time period', sharing the regeneration Gas heater, namely using the processed dry natural Gas or Boil Off Gas (BOG) of the LNG plant as the regeneration Gas source, the regeneration period is as follows: when the molecular sieve of the LNG plant is heated, the molecular sieve is cold-blown to the first drying tower 28 or the second drying tower 29; when the LNG plant molecular sieve is cold blown, the first drying tower 28 or the second drying tower 29 is heated. Taking the first drying tower 28 working on line and the second drying tower 29 regenerating as an example, the high-pressure CO is compressed by a carbon dioxide compressor, cooled and separated into gas and liquid2Enters the first drying tower 28 from the top of the first drying tower 28 through the program control valve 59, is deeply dried, then exits the drying tower from the bottom of the first drying tower 28, and leaves the drying unit through the program control valve 62 and the drying outlet pipeline 30; meanwhile, the molecular sieve desiccant in the second drying tower 29 is regenerated, and the regeneration gas from the regeneration gas unit of the LNG plant enters the second drying tower 29 from the bottom of the second drying tower 29 through the program control valve 63 and then enters the regeneration gas cooler 65 through the program control valve 58. (programmable valves 53-56 are bypass valves arranged for equalizing pressure of the drying towers; the programmable valve 84 is a bypass valve, and when the regeneration gas does not flow into any drying tower, the regeneration gas bypasses the programmable valve 84 and enters a downstream pipeline of the regeneration gas.)
The regeneration gas is cooled by a regeneration gas cooler 65, enters a regeneration gas-liquid separator 66 to separate free water, and then is discharged out of the device through a regeneration gas return pipeline 52 to be used as CO2Fuel gas from the liquefaction recovery unit (if the unit is equipped with self-generating electricity) or returned to the LNG plant fuel gas main.
CO in acid gas after desulfurization, dehydration and deep drying2The purity is generally over 99 percent, and the purity completely reaches the CO in the oil and gas field2Purity requirement of fracturing. The gas thus enters the CO via the dry outlet duct 302Cooling to-25-30 deg.C in cooler 31, liquefying and supercooling, and passing through CO2Throttle valve 33 throttles to liquid CO2After storing the pressure, the liquid CO is introduced2The storage tank 35 stores. Liquid CO for external delivery2Passing through liquid CO2Product line 37 is bottled or loaded and a small amount of flash gas is returned to the acid gas inlet via BOG line 36.
For CO2The refrigerant circulation flow of the cooler 31 is: from CO2The environment-friendly refrigerant (such as R507) flowing back from the cooler 31 enters the inlet separator 39 of the refrigerant compressor through the refrigerant return pipeline 38 at about normal temperature, is subjected to gas-liquid separation to remove a small amount of liquid impurities possibly existing in the refrigerant, enters the primary compression 41 of the refrigerant compressor through the separator outlet pipeline 40 at the top of the inlet separator 39 of the refrigerant compressor, enters the fourth air cooler 43 to be cooled to normal temperature after the primary compression, enters the secondary compression 45 of the refrigerant compressor to be subjected to secondary compression, enters the fifth air cooler 47 to be cooled to normal temperature, is throttled to lower pressure and temperature of about-30 ℃ to-38 ℃ through the refrigerant throttle valve 49, enters the CO after the CO is throttled to the lower pressure and the temperature of about-30 ℃ to-38 DEG C2The cooler 31 is CO to be liquefied2Providing cold. The refrigerant with the supplied cold energy flows back through the refrigerant return pipe 38, and the next refrigerant cycle is performed.
Example 2 preparation of high purity (food grade) liquid CO from LNG plant AGRU stripper overhead sour gas2
Liquid CO2In addition to fracturing oil and gas fields, it is also widely used in other industries, such as the food industry. But CO for food2To CO2The purity of (b) has a high demand, for which this example, based on example 1, captures and purifies liquefied CO for LNG plants2The process technology is further improved, and a low-temperature rectification purification process is added to prepare high-purity liquid CO2。
As shown in FIG. 2, CO of the present embodiment2The capture liquefaction recovery apparatus, the pretreatment unit, the compression unit, and the drying unit thereof were the same as those of example 1, and unlike example 1, in this example, the cold box 67 was used in the liquefaction recovery unit instead of CO2A cooler 31 and a cryogenic rectification column 74 added after the cold box 67.
The cold box 67 is used for cooling and liquefying CO from the tops of the first drying tower 28 and the second drying tower 292A gas. In this embodiment, the cold box 67 is an expanded perlite cold insulation cold box, and a plate-fin heat exchanger is installed in the cold box 67 (in other embodiments, other forms of multi-channel heat exchangers may be used). At the top of the cold box 67CO2The inlet is connected with a dry outlet pipeline 30, and the bottom part is provided with a cold box CO2An outlet pipe 73 is connected to the top inlet of the cryogenic rectification column 74. The middle part of the cold box 67 is provided with CO2The precooling pipeline 71 is connected with the middle inlet of the low-temperature rectifying tower 74, and CO2The flow rate control valve 72 is mounted on the pre-cooling pipe 71. The refrigerant outlet at the top of the cold box 67 is connected to a refrigerant return line 68. A refrigerant return line 68 connects the inlet of the refrigerant compressor inlet separator 39. The refrigerant inlet at the top of the cold box 67 is connected to the fifth air cooler outlet duct 48. The bottom of the cold box 67 is provided with a high-pressure refrigerant outlet cold box pipeline 70 which is connected with a refrigerant inlet and outlet cold box flow passage in the cold box 67. A refrigerant throttle 69 is installed on the high-pressure refrigerant outlet tank pipe 70.
The cryogenic rectification tower 74 is used for purifying the CO cooled and liquefied by the cold box 67 by a cryogenic rectification method2. The top outlet of the low-temperature rectifying tower 74 is provided with a non-condensable gas pipeline 78, and the bottom outlet is provided with high-pressure liquid CO2Pipe 75 connects CO2Inlet of throttle valve 76, CO2The outlet of the throttle valve 76 is passed through low pressure liquid CO2Pipe 77 for connecting liquid CO2An inlet of the reservoir 35. The bottom of the low temperature rectifying tower 74 is provided with a reboiler 81 for controlling CO at the bottom of the low temperature rectifying tower 742The purity of (2). The reboiler 81 is provided with a heat source line 79 from the LNG plant and a heat source line 82 returning to the LNG plant, and the heat source line 79 from the LNG plant is provided with a temperature control valve 80 for controlling the heat load of the reboiler 81.
Other equipment of the liquefaction recovery unit (refrigerant compressor inlet separator 39, refrigerant compressor first stage compression 41, fourth air cooler 43, refrigerant compressor second stage compression 45, fifth air cooler 47 and liquid CO2Reservoir 35, etc.) and the connection are the same as in example 1.
The device of the embodiment is used for capturing, liquefying and recovering high-purity and high-purity (food grade) liquid CO from the acid gas removed from the overhead of the AGRU stripping tower of the LNG plant2The specific process flow is as follows:
as shown in fig. 2, the sour gas from the AGRU stripping tower of the LNG plant is sequentially subjected to desulfurization, dehydration pretreatment, three-stage compression, temperature reduction, dehydration, and deep drying,i.e. sour gas is derived from CO2The process flow of the raw material pipeline 01 entering the drying tower and entering the drying outlet pipeline 30 is the same as the process flow of the embodiment 1.
Crude CO desulfurized, dehydrated and deeply dried2CO which exits the drying tower and enters the plate-fin heat exchanger in the cold box 67 through the drying outlet pipe 302The channel, after being cooled to an intermediate temperature, has a portion of CO2CO from the middle of the cold box 672The pre-cooling pipeline 71 is pumped out, and the flow is adjusted by a flow adjusting valve 72 to be used as a feed to enter a low-temperature rectifying tower 74; and another part of CO2It continues to be cooled to a lower temperature in the lower half of the same tunnel, passing through the cold box CO at the bottom of the cold box 672The outlet pipe 73 enters the top of the low-temperature rectifying tower 74 to be used as a top cold source of the low-temperature rectifying tower 74.
Cooled CO2After purification in the low temperature rectification column 74, high purity liquid CO2The product passes through high-pressure liquid CO at the bottom of the low-temperature rectifying tower 742 Line 75 and through CO2Throttle valve 76 throttles to liquid CO2After storage pressure of (2), into liquid CO2The storage tank 35 stores. Liquid CO for external transportation2Passing through liquid CO2Product line 37 is bottled or loaded and a small amount of flash gas is returned to the acid gas inlet via BOG line 36. A small amount of non-condensable gases are discharged from a non-condensable gas line 78 at the top of the cryogenic rectification column 74.
The heat source of the reboiler 81 at the bottom of the cryogenic rectification column 74 is integrated with the LNG plant, i.e. the LNG plant is used to process dry qualified natural gas as the heat source of the reboiler 81, and the heat load is controlled by the bottom temperature control valve 80 to ensure the bottom liquid CO2The purity of the product.
The circulation flow of the refrigerant for the cold box 67 is: the environment-friendly refrigerating medium which flows back from the cold box 67 enters the inlet separator 39 of the refrigerant compressor through the refrigerant return pipeline 68 at about normal temperature, liquid impurities in the refrigerant are removed through gas-liquid separation, the refrigerant enters the primary compression 41 of the refrigerant compressor through the outlet pipeline 40 of the separator (at the moment, the temperature of the refrigerant is about 20 ℃, the pressure is about 2.0bar or lower), and the refrigerant enters the fourth air cooler 43 for cooling after the primary compressionCooling to normal temperature, performing secondary compression in a secondary compression 45 of a refrigerant compressor, cooling to normal temperature in a fifth air cooler 47, entering a cold box 67, discharging high-pressure refrigerant out of the cold box 67, throttling to lower pressure and temperature of about-30 ℃ to-38 ℃ through a refrigerant throttle valve 69, and entering the cold box 67 again to obtain CO to be liquefied2Providing cold energy. The refrigerant after providing the cooling capacity is returned through the refrigerant return pipe 68 to perform the next refrigerant cycle.
In this embodiment, after the cryogenic rectification purification process is added, the acid gas CO removed from the AGRU stripping tower of the LNG plant can be removed2The purification is carried out to the high purity of 99.99 percent, and meanwhile, a small part of natural gas of the LNG factory can be precooled by a low-temperature rectifying tower reboiler, so that the overall energy efficiency of the LNG factory can be improved.
Some LNG plants desire CO for real-world problems or regulatory needs2The capture liquefaction recovery apparatus has its own heat source and does not use a heat source from the LNG plant, and in this case, the heat source of the reboiler 81 may be changed to electric heating, that is, the reboiler 81 may be supplied with heat by using an electric heater 83, as shown in fig. 3.

Claims (13)

1. The carbon dioxide capture liquefaction recovery device is characterized by comprising: the device comprises a pretreatment unit, a compression unit, a drying unit and a liquefaction recovery unit; wherein the content of the first and second substances,
the pretreatment unit comprises a desulfurizing tower and a precooling separator; the inlet of the desulfurizing tower is connected with an acid gas outlet at the top of a stripping tower of an acid gas removal unit of an LNG factory through a pipeline, and the outlet of the desulfurizing tower is connected with the inlet of the precooling separator through a pipeline;
the compression unit is arranged behind the pretreatment unit and comprises a carbon dioxide compressor, an air cooler and a gas-liquid separator; the compression stage number of the carbon dioxide compressor is more than or equal to 1, the inlet of the first-stage compression is connected with the outlet of the precooling separator of the pretreatment unit through a pipeline, an air cooler and a gas-liquid separator are respectively and sequentially arranged after each stage of compression, the inlet of the air cooler is connected with the outlet of the first-stage compression through a pipeline, the outlet of the air cooler is connected with the inlet of the gas-liquid separator through a pipeline, the outlet of the gas-liquid separator is connected with the inlet of the next-stage compression through a pipeline, and the outlet of the last-stage gas-liquid separator is communicated with the drying unit through a pipeline;
the drying unit is arranged behind the compression unit and comprises more than one drying tower; a carbon dioxide inlet of the drying tower is connected with an outlet of the last stage of gas-liquid separator of the compression unit through a pipeline; a carbon dioxide outlet of the drying tower leads to the liquefaction recovery unit through a pipeline;
the liquefaction recovery unit is arranged behind the drying unit and comprises heat exchange equipment and a liquid carbon dioxide storage tank; a carbon dioxide inlet of the heat exchange equipment is connected with an outlet of the drying tower through a pipeline; a carbon dioxide outlet of the heat exchange device is communicated with an inlet of the liquid carbon dioxide storage tank; and a liquid carbon dioxide product pipeline is arranged at an outlet at the bottom of the liquid carbon dioxide storage tank.
2. The device of claim 1, wherein a regeneration gas inlet of the drying tower is connected with a regeneration gas inlet pipeline from an LNG plant, the drying unit further comprises a regeneration gas cooler and a regeneration gas-liquid separator, an inlet of the regeneration gas cooler is connected with a regeneration gas outlet of the drying tower through a pipeline, an outlet of the regeneration gas cooler is connected with an inlet of the regeneration gas-liquid separator through a pipeline, and an outlet of the regeneration gas-liquid separator is connected with a regeneration gas return pipeline leading to the LNG plant through a pipeline.
3. The apparatus of claim 1, wherein the liquefaction recovery unit further comprises a refrigerant compressor inlet separator, a refrigerant compressor, and an air cooler; a refrigerant outlet of the heat exchange equipment is connected with an inlet of the refrigerant compressor inlet separator through a pipeline; the refrigerant compressor has the compression stage number more than or equal to 1, the inlet of the first-stage compression is connected with the outlet of the inlet separator of the refrigerant compressor through a pipeline, an air cooler is arranged after each stage of compression, the inlet of the air cooler is connected with the outlet of the first-stage compression through a pipeline, the outlet of the air cooler is connected with the inlet of the next-stage compression through a pipeline, and the outlet of the last-stage air cooler is connected with the refrigerant inlet of the heat exchange equipment through a pipeline.
4. The device according to claim 3, wherein the heat exchange equipment is a carbon dioxide cooler, the carbon dioxide cooler is a shell-and-tube heat exchanger, and a refrigerant throttle valve is arranged on a pipeline between a refrigerant inlet of the carbon dioxide cooler and an outlet of the last stage air cooler.
5. The device according to claim 3, wherein the heat exchange equipment is a cold box, a multi-flow-channel heat exchanger is arranged in the cold box, and a low-temperature rectifying tower is arranged on a pipeline between the cold box and the liquid carbon dioxide storage tank.
6. The device according to claim 5, wherein the middle part and the bottom part of the cold box are respectively provided with a carbon dioxide outlet, the carbon dioxide outlet in the middle part of the cold box is connected with the middle inlet of the low-temperature rectifying tower through a pipeline, and the carbon dioxide outlet in the bottom part of the cold box is connected with the top inlet of the low-temperature rectifying tower through a pipeline; a non-condensable gas pipeline is arranged at an outlet at the top of the low-temperature rectifying tower, and an outlet at the bottom of the low-temperature rectifying tower is connected with the liquid carbon dioxide storage tank through a pipeline; and a reboiler is arranged at the lower part of the low-temperature rectifying tower.
7. The apparatus of claim 6, wherein a heat source transfer line and a heat source return LNG plant line are provided between the reboiler and the LNG plant, and wherein the heat source transfer line has a temperature control valve mounted thereon.
8. The apparatus of claim 6, wherein the reboiler is an electric heater.
9. The carbon dioxide capture liquefaction recovery method based on any one of claims 1 to 8, characterized by comprising the steps of:
1) pretreatment: carrying out desulfurization and dehydration pretreatment on acid gas from the top of a stripping tower of an acid gas removal unit of an LNG plant;
2) compression: the acid gas after pretreatment is compressed by more than one stage, and cooling and gas-liquid separation and dehydration are respectively carried out after each stage of compression;
3) and (3) drying: drying the compressed acid gas in a drying tower;
4) liquefaction and recovery: and (3) sending the acid gas dried in the step 3) into heat exchange equipment to exchange heat with refrigerant, liquefying the acid gas into liquid carbon dioxide, and sending the liquid carbon dioxide into a liquid carbon dioxide storage tank to be stored.
10. The method of claim 9, wherein the regeneration of the drying tower in step 3) uses the treated dry natural gas or boil-off gas of the LNG plant as a source of the regeneration gas, and the heated regeneration gas is cooled and dehydrated and returned to the LNG plant.
11. The method according to claim 9, wherein in step 4), the refrigerant circulation process is as follows: the refrigerant flows out of the heat exchange equipment, is subjected to gas-liquid separation, and is compressed and cooled by more than one stage, and then flows back to the heat exchanger.
12. The method of claim 9, wherein step 4) further comprises a rectification step before the liquid carbon dioxide enters the liquid carbon dioxide storage tank for storage.
13. The method according to claim 12, wherein in step 4), after the acid gas is cooled to an intermediate temperature in the heat exchange device, a part of the acid gas is extracted from the middle part of the heat exchange device to be purified by cryogenic rectification; and the other part of the acid gas is continuously cooled to a lower temperature, and leaves from the bottom of the heat exchange device to be used as a cold source for low-temperature rectification.
CN202011312939.3A 2020-11-20 2020-11-20 Carbon dioxide capturing, liquefying and recycling device and method Pending CN114518016A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115121083A (en) * 2022-07-13 2022-09-30 中国科学院过程工程研究所 Device and method for purifying and separating ammonia-containing tail gas in production process of carbonylation intermediate
CN115388616A (en) * 2022-08-25 2022-11-25 北京航天试验技术研究所 Mars surface carbon dioxide continuous capturing system adopting pressurization liquefaction and method thereof

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115121083A (en) * 2022-07-13 2022-09-30 中国科学院过程工程研究所 Device and method for purifying and separating ammonia-containing tail gas in production process of carbonylation intermediate
CN115121083B (en) * 2022-07-13 2024-03-01 中国科学院过程工程研究所 Device and method for purifying and separating ammonia-containing tail gas in carbonylation intermediate production process
CN115388616A (en) * 2022-08-25 2022-11-25 北京航天试验技术研究所 Mars surface carbon dioxide continuous capturing system adopting pressurization liquefaction and method thereof
CN115388616B (en) * 2022-08-25 2023-06-16 北京航天试验技术研究所 Mars surface carbon dioxide continuous capturing system adopting pressurizing liquefaction and method thereof

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