CN114440552A - Method for extracting and liquefying high-purity methane by using liquefied natural gas - Google Patents
Method for extracting and liquefying high-purity methane by using liquefied natural gas Download PDFInfo
- Publication number
- CN114440552A CN114440552A CN202210108138.8A CN202210108138A CN114440552A CN 114440552 A CN114440552 A CN 114440552A CN 202210108138 A CN202210108138 A CN 202210108138A CN 114440552 A CN114440552 A CN 114440552A
- Authority
- CN
- China
- Prior art keywords
- tower
- rectifying tower
- heat exchanger
- channel
- refrigerant
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 124
- 239000003949 liquefied natural gas Substances 0.000 title claims abstract description 68
- 238000000034 method Methods 0.000 title claims abstract description 38
- 238000010992 reflux Methods 0.000 claims abstract description 61
- 239000007788 liquid Substances 0.000 claims abstract description 56
- 238000009833 condensation Methods 0.000 claims abstract description 51
- 230000005494 condensation Effects 0.000 claims abstract description 51
- 238000012546 transfer Methods 0.000 claims abstract description 13
- 238000000605 extraction Methods 0.000 claims abstract description 11
- 238000003860 storage Methods 0.000 claims abstract description 7
- 239000003507 refrigerant Substances 0.000 claims description 77
- 239000007789 gas Substances 0.000 claims description 41
- 238000010926 purge Methods 0.000 claims description 10
- 238000005057 refrigeration Methods 0.000 claims description 9
- 150000001335 aliphatic alkanes Chemical class 0.000 claims description 8
- 239000003345 natural gas Substances 0.000 claims description 7
- 229910052782 aluminium Inorganic materials 0.000 claims description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 6
- 230000001105 regulatory effect Effects 0.000 claims description 6
- 238000003303 reheating Methods 0.000 claims description 6
- 238000012856 packing Methods 0.000 claims description 4
- 230000001174 ascending effect Effects 0.000 claims description 3
- 230000006835 compression Effects 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 239000000284 extract Substances 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 abstract description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 2
- 238000007792 addition Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000000945 filler Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001294 propane Substances 0.000 description 2
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001312 dry etching Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- -1 microbial culture Substances 0.000 description 1
- 238000009629 microbiological culture Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000001020 plasma etching Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Images
Classifications
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/0204—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the feed stream
- F25J3/0209—Natural gas or substitute natural gas
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/0204—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the feed stream
- F25J3/0209—Natural gas or substitute natural gas
- F25J3/0214—Liquefied natural gas
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
- F25J3/0233—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of CnHm with 1 carbon atom or more
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
- F25J3/0238—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of CnHm with 2 carbon atoms or more
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
- F25J3/0257—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of nitrogen
-
- 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
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/08—Separating gaseous impurities from gases or gaseous mixtures or from liquefied gases or liquefied gaseous mixtures
-
- 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
- F25J2200/00—Processes or apparatus using separation by rectification
- F25J2200/04—Processes or apparatus using separation by rectification in a dual pressure main column system
-
- 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
- F25J2200/00—Processes or apparatus using separation by rectification
- F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
- F25J2200/54—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column in the low pressure column of a double pressure main column system
-
- 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
- F25J2200/00—Processes or apparatus using separation by rectification
- F25J2200/74—Refluxing the column with at least a part of the partially condensed overhead gas
-
- 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
- F25J2215/00—Processes characterised by the type or other details of the product stream
- F25J2215/04—Recovery of liquid products
-
- 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
- F25J2215/00—Processes characterised by the type or other details of the product stream
- F25J2215/60—Methane
-
- 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
- F25J2235/00—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams
- F25J2235/60—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams the fluid being (a mixture of) hydrocarbons
-
- 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
- F25J2270/42—Quasi-closed internal or closed external nitrogen refrigeration cycle
-
- 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
- F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
- F25J2290/34—Details about subcooling of liquids
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- 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)
- Separation By Low-Temperature Treatments (AREA)
Abstract
The invention relates to a method for extracting and liquefying high-purity methane by using liquefied natural gas, which is implemented by adopting a high-purity methane extraction and liquefaction system, wherein the high-purity methane extraction and liquefaction system comprises an LNG buffer tank, an LNG transfer pump, a lower rectifying tower, an upper rectifying tower bottom condensation evaporator, an upper rectifying tower top condensation heat exchanger, a lower rectifying tower top reflux tank, an upper rectifying tower top reflux tank and a heat exchanger. The method uses liquefied natural gas as a raw material, extracts, separates and liquefies methane to obtain high-purity liquid methane, adopts a low-temperature storage tank for storage and a low-temperature tank car for remote distribution, and meets the requirements of different customers.
Description
Technical Field
The invention relates to the technical field of high-purity gas preparation, in particular to a method for extracting and liquefying high-purity methane by utilizing liquefied natural gas.
Background
The main component of the conventional type of liquefied natural gas is methane (CH)4) Ethane (C)2H6) And also a small amount of propane (C)3H8) Nitrogen (N)2) Oxygen (O)2) Etc. of which CH4The volume fraction of C is 86.0% -97.5%4 +Alkane volume fraction is less than or equal to 2 percent, CO2Volume fraction is less than or equal to 0.01 percent, N2Volume fraction of less than or equal to 1 percent and O2Volume fraction is less than or equal to 0.1 percent, H2The S content is less than or equal to 3.5mg/m3。
High purity methane is CH4Methane with volume fraction more than or equal to 99.999 percent. The high-purity methane is not only used for preparing and catalyzing standard mixed gasThe method is applied to the fields of agent evaluation, carburization and carbide generation of metals and alloys, microbial culture, refrigerants and the like, and is gradually used for manufacturing amorphous silicon solar cells, dry etching of large-scale integrated circuits or auxiliary gas addition of plasma etching gas.
At present, a system and a method for extracting high-purity methane from liquefied natural gas do not exist, and in order to meet the market demand for high-purity methane, it is necessary to develop a device and an extraction method for extracting high-purity methane from liquefied natural gas, so as to produce high-purity liquid methane, store the high-purity liquid methane by using a low-temperature storage tank and remotely distribute the high-purity liquid methane by using a low-temperature tank car, and meet different customer demands.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide a method for extracting and liquefying high-purity methane by using liquefied natural gas.
The technical scheme adopted by the invention for solving the problems is as follows: a method for extracting and liquefying high-purity methane by using liquefied natural gas is implemented by adopting a high-purity methane extraction and liquefaction system, wherein the high-purity methane extraction and liquefaction system comprises an LNG buffer tank, an LNG transfer pump, a lower rectifying tower, an upper rectifying tower bottom condensation evaporator, an upper rectifying tower top condensation heat exchanger, a lower rectifying tower top reflux tank, an upper rectifying tower top reflux tank and a heat exchanger, and the heat exchanger is provided with a channel A, a channel D and a channel E; the method is characterized in that: the method for extracting and liquefying high-purity methane by using liquefied natural gas comprises the following steps:
the method comprises the following steps: the liquefied natural gas enters an LNG buffer tank, the liquefied natural gas in the LNG buffer tank is pressurized through an LNG transfer pump, the pressurized liquefied natural gas enters a channel A of a heat exchanger to be heated and gasified, and the gasified gaseous natural gas comes out of the channel A;
step two: the gaseous natural gas from the channel A enters the bottom of the lower tower of the rectifying tower, steam stripping rectification is carried out in the lower tower of the rectifying tower, alkane heavy components are separated out, the separated alkane heavy components enter a channel E of the heat exchanger for rewarming after coming out from the bottom of the lower tower of the rectifying tower, and the rewarming gas is used as purge gas to be discharged outside;
step three: gas coming out of the upper part of the lower tower of the rectifying tower enters a condensing evaporator at the bottom of the upper tower of the rectifying tower, is cooled by the condensing evaporator at the bottom of the upper tower of the rectifying tower and then enters a reflux tank at the top of the lower tower of the rectifying tower, and liquid coming out of the bottom of the reflux tank at the top of the lower tower of the rectifying tower enters the top of the lower tower of the rectifying tower and serves as reflux liquid of the lower tower of the rectifying tower; gas coming out of the top of a reflux tank at the top of a lower tower of the rectifying tower enters from the middle of an upper tower of the rectifying tower after the pressure of the gas is controlled by a regulating valve, and is rectified and removed of light components in the upper tower of the rectifying tower;
step four: liquid from the bottom of the upper tower of the rectifying tower is high-purity liquid methane, and is subcooled by a channel D of the heat exchanger and then is stored in an external storage tank as a high-purity liquid methane product; gas coming out of the top of the upper tower of the rectifying tower enters a condensing heat exchanger at the top of the upper tower of the rectifying tower, is cooled by the condensing heat exchanger at the top of the upper tower of the rectifying tower and then enters a reflux tank at the top of the upper tower of the rectifying tower, and liquid coming out of the bottom of the reflux tank at the top of the upper tower of the rectifying tower enters from the top of the upper tower of the rectifying tower and participates in rectification as reflux liquid of the upper tower of the rectifying tower; and (3) gas coming out from the top of the reflux tank at the top of the upper tower of the rectifying tower enters a channel E of the heat exchanger for reheating, and is used as purge gas to go out after reheating.
Preferably, the high-purity methane extraction liquefaction system further comprises a refrigerant compressor, and the heat exchanger is further provided with a channel B and a channel C; the refrigerant outlet of the refrigerant compressor is communicated with the inlet end of the channel C through a first refrigerant circulation pipeline, the outlet end of the channel C is communicated with the refrigerant inlet of the condensation evaporator at the bottom of the rectifying tower upper tower through a second refrigerant circulation pipeline, the refrigerant outlet of the condensation evaporator at the bottom of the rectifying tower upper tower is communicated with the refrigerant inlet of the condensation heat exchanger at the top of the rectifying tower upper tower through a third refrigerant circulation pipeline, the refrigerant outlet of the condensation heat exchanger at the top of the rectifying tower upper tower is communicated with the inlet end of the channel B through a fourth refrigerant circulation pipeline, and the outlet end of the channel B is communicated with the refrigerant inlet of the refrigerant compressor through a fifth refrigerant circulation pipeline.
Preferably, the cold energy required by the heat exchanger and the cold energy required by the condensing heat exchanger on the top of the upper tower of the rectifying tower are provided by closed cryogen first-stage throttling refrigeration; the circulating refrigeration method comprises the following steps: the method comprises the following steps that a refrigerant is pressurized by a refrigerant compressor and then enters a channel C of a heat exchanger for precooling, the refrigerant is precooled to a certain temperature and then comes out of the channel C, the refrigerant coming out enters a condensation evaporator at the bottom of an upper tower of a rectifying tower and is cooled and liquefied by the condensation evaporator at the bottom of the upper tower of the rectifying tower, and ascending steam stripping is provided for the upper tower of the rectifying tower; liquid refrigerant coming out of the condensation evaporator at the bottom of the upper tower of the rectifying tower enters the condensation heat exchanger at the top of the upper tower of the rectifying tower after the pressure of the liquid refrigerant is controlled by a regulating valve, so that a cold source is provided for the condensation heat exchanger at the top of the upper tower of the rectifying tower; and the gas refrigerant coming out of the condensing heat exchanger at the top of the upper tower of the rectifying tower enters a channel B of the heat exchanger to provide cold energy for the heat exchanger, and the gas refrigerant after being reheated by the heat exchanger enters a refrigerant compressor to realize the circulating compression throttling refrigeration of the refrigerant.
Preferably, the lower rectifying tower, the condensing evaporator at the bottom of the upper rectifying tower, the upper rectifying tower and the condensing heat exchanger at the top of the upper rectifying tower are arranged from bottom to top; the LNG buffer tank is used for storing liquefied natural gas, the LNG buffer tank is communicated with the inlet end of the channel A through a first pipeline, the LNG transfer pump is installed on the first pipeline, and the outlet end of the channel A is communicated with the middle gas inlet of the lower tower of the rectifying tower through a second pipeline; an air outlet at the upper part of the lower rectifying tower is communicated with an air inlet of a condensation evaporator at the bottom of the upper rectifying tower through a third pipeline; a liquid outlet of the condensation evaporator at the bottom of the upper tower of the rectifying tower is communicated with a liquid inlet of a reflux tank at the top of the lower tower of the rectifying tower through a fourth pipeline; a bottom liquid outlet of the reflux tank at the top of the lower rectifying tower is communicated with a reflux liquid inlet of the lower rectifying tower through a fifth pipeline, and a top gas outlet of the reflux tank at the top of the lower rectifying tower is communicated with a middle inlet of the upper rectifying tower through a sixth pipeline; a liquid outlet at the bottom of the upper tower of the rectifying tower is communicated with the inlet end of the channel D through a No. seven pipeline, and the outlet end of the channel D is communicated with a high-purity liquid methane product conveying pipeline; an air outlet at the upper part of the upper tower of the rectifying tower is communicated with an air inlet of a condensing heat exchanger at the top of the upper tower of the rectifying tower through an eighth pipeline; a liquid outlet of the condensation heat exchanger at the top of the upper tower of the rectifying tower is communicated with a liquid inlet of a reflux tank at the top of the upper tower of the rectifying tower through a ninth pipeline, a liquid outlet at the bottom of the reflux tank at the top of the upper tower of the rectifying tower is communicated with a reflux inlet of the upper tower of the rectifying tower through a tenth pipeline, a top gas outlet of the reflux tank at the top of the upper tower of the rectifying tower is communicated with an inlet end of a channel E through an eleventh pipeline, and an outlet end of the channel E is communicated with a purge gas output pipeline; and the bottom outlet of the lower tower of the rectifying tower is communicated with the inlet end of the channel E through a No. twelve pipeline.
Preferably, the LNG transfer pump is a centrifugal pump.
Preferably, the heat exchanger is an aluminum plate-fin heat exchanger.
Preferably, the condensation evaporator at the bottom of the upper tower part of the rectifying tower is a submerged plate-fin heat exchanger with two heat flows.
Preferably, the top condensing heat exchanger of the rectifying tower is a submerged plate-fin heat exchanger with a heat flow.
Preferably, the packing of the upper tower of the rectifying tower adopts aluminum corrugated regular packing.
Compared with the prior art, the invention has the following advantages and effects: the system utilizes liquefied natural gas as a raw material, extracts, separates and liquefies methane to obtain high-purity liquid methane, adopts the low-temperature storage tank to store methane and adopts the low-temperature tank car to remotely deliver methane, and meets the requirements of different customers.
Drawings
In order to illustrate the embodiments of the present invention or the solutions in the prior art more clearly, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive effort.
Fig. 1 is a schematic structural diagram of an embodiment of the present invention.
Description of reference numerals: an LNG buffer tank 1; an LNG transfer pump 2; a lower rectifying tower 3; the evaporator 4 is condensed at the bottom of the upper tower of the rectifying tower; a reflux tank 5 is arranged at the top of the lower tower of the rectifying tower; the rectifying tower is arranged on the tower 6; a condensing heat exchanger 7 is arranged at the top of the upper tower of the rectifying tower; a reflux tank 8 is arranged at the top of the rectifying tower; a refrigerant compressor 9; a heat exchanger 10; a first pipeline 11; a second pipeline 12; a third pipeline 13; line number four 14; a fifth pipeline 15; line number six 16; a seventh pipe 17; a high purity liquid methane product delivery line 18; line eight 19; line No. nine, 20; a tenth pipe 21; line number eleven 22; a purge gas output line 23; a twelfth pipeline 24; a first refrigerant circulation line 25; a second refrigerant circulation line 26; a third refrigerant circulation line 27; a fourth refrigerant circulation line 28; and a fifth refrigerant circulation line 29.
Detailed Description
The present invention will be described in further detail below by way of examples with reference to the accompanying drawings, which are illustrative of the present invention and are not to be construed as limiting the present invention.
Examples are given.
See fig. 1.
The embodiment of the invention discloses a high-purity methane extraction and liquefaction system, which is a system device for extracting and liquefying high-purity methane by utilizing liquefied natural gas, and comprises an LNG buffer tank 1, an LNG transfer pump 2, a rectifying tower lower tower 3, a rectifying tower upper tower bottom condensation evaporator 4, a rectifying tower upper tower 6, a rectifying tower upper tower top condensation heat exchanger 7, a rectifying tower lower tower top reflux tank 5, a rectifying tower upper tower top reflux tank 8, a refrigerant compressor 9 and a heat exchanger 10. The heat exchanger 10 is provided with a channel A, a channel B, a channel C, a channel D and a channel E, the LNG conveying pump 2 adopts a centrifugal pump, the heat exchanger 10 adopts an aluminum plate-fin heat exchanger, the condensing evaporator 4 at the bottom of the upper tower part of the rectifying tower is an immersed plate-fin heat exchanger with two heat flows, the condensing heat exchanger 7 at the top of the upper tower part of the rectifying tower is an immersed plate-fin heat exchanger with one heat flow, and the filler of the upper tower 6 of the rectifying tower adopts aluminum corrugated regular filler.
In this embodiment, the lower rectifying tower 3, the upper rectifying tower bottom condensation evaporator 4, the upper rectifying tower 6 and the upper rectifying tower top condensation heat exchanger 7 are arranged from bottom to top. The whole rectifying tower system is composed of a lower rectifying tower 3, an upper rectifying tower bottom condensation evaporator 4, an upper rectifying tower 6, an upper rectifying tower top condensation heat exchanger 7, a lower rectifying tower top reflux tank 5, an upper rectifying tower top reflux tank 8, and pipelines and valves matched with the reflux tanks.
In this embodiment, LNG buffer tank 1 is used for storing liquefied natural gas, and LNG buffer tank 1 and passageway a's entrance point are through No. 11 switch-ons of a pipeline to LNG transfer pump 2 installs on No. 11 pipelines, and passageway a's exit end and rectifying column lower tower 3's middle part air inlet are through No. 12 switch-ons of No. two pipelines. The channel A has the function of warming, and the liquefied natural gas is gasified into gaseous natural gas.
In the embodiment, an air outlet at the upper part of the lower rectifying tower 3 is communicated with an air inlet of the condensation evaporator 4 at the bottom of the upper rectifying tower through a third pipeline 13; the liquid outlet of the upper tower bottom condensation evaporator 4 of the rectifying tower is communicated with the liquid inlet of the lower tower top reflux tank 5 of the rectifying tower through a fourth pipeline 14.
In this embodiment, the bottom liquid outlet of the reflux drum 5 at the top of the lower tower of the rectifying tower is communicated with the reflux inlet of the lower tower 3 of the rectifying tower through a fifth pipeline 15, and the top gas outlet of the reflux drum 5 at the top of the lower tower of the rectifying tower is communicated with the middle inlet of the upper tower 6 of the rectifying tower through a sixth pipeline 16.
In this embodiment, a liquid outlet at the bottom of the upper column 6 of the rectifying column is communicated with an inlet end of the channel D through a seventh pipeline 17, and an outlet end of the channel D is communicated with a high-purity liquid methane product conveying pipeline 18. An air outlet at the upper part of the upper tower 6 of the rectifying tower is communicated with an air inlet of a condensation heat exchanger 7 at the top of the upper tower of the rectifying tower through an eighth pipeline 19.
In this embodiment, a liquid outlet of the condensing heat exchanger 7 at the top of the upper tower of the rectifying tower is communicated with a liquid inlet of the reflux tank 8 at the top of the upper tower of the rectifying tower through a ninth pipeline 20, a liquid outlet at the bottom of the reflux tank 8 at the top of the upper tower of the rectifying tower is communicated with a reflux inlet of the upper tower 6 of the rectifying tower through a tenth pipeline 21, a top gas outlet of the reflux tank 8 at the top of the upper tower of the rectifying tower is communicated with an inlet end of a channel E through an eleventh pipeline 22, and an outlet end of the channel E is communicated with a purge gas output pipeline 23; the bottom outlet of the lower rectifying tower 3 is communicated with the inlet end of the channel E through a No. twelve pipeline 24.
In this embodiment, the refrigerant outlet of the refrigerant compressor 9 is connected to the inlet end of the channel C through a first refrigerant circulation pipeline 25, the outlet end of the channel C is connected to the refrigerant inlet of the upper tower bottom condensation evaporator 4 of the rectifying tower through a second refrigerant circulation pipeline 26, the refrigerant outlet of the upper tower bottom condensation evaporator 4 of the rectifying tower is connected to the refrigerant inlet of the upper tower top condensation heat exchanger 7 of the rectifying tower through a third refrigerant circulation pipeline 27, the refrigerant outlet of the upper tower top condensation heat exchanger 7 of the rectifying tower is connected to the inlet end of the channel B through a fourth refrigerant circulation pipeline 28, and the outlet end of the channel B is connected to the refrigerant inlet of the refrigerant compressor 9 through a fifth refrigerant circulation pipeline 29.
In this embodiment, the method for extracting and liquefying high-purity methane from liquefied natural gas by using the high-purity methane extraction and liquefaction system includes the steps of:
the method comprises the following steps: liquefied natural gas enters an LNG buffer tank 1, the liquefied natural gas in the LNG buffer tank 1 is pressurized through an LNG transfer pump 2, the pressurized liquefied natural gas enters a channel A of a heat exchanger 10 to be heated and gasified, and gasified gaseous natural gas comes out from the channel A;
step two: the gaseous natural gas from the channel A enters the bottom of a lower tower 3 of the rectifying tower, and is subjected to steam stripping rectification in the lower tower 3 of the rectifying tower to separate carbon dioxide and H2S, ethane, propane, C4And the alkane heavy components are separated, the separated alkane heavy components come out from the bottom of a lower tower 3 of the rectifying tower and enter a channel E of a heat exchanger 10 for rewarming, and the rewarming gas is used as purge gas to be discharged outside;
step three: gas coming out of the upper part of the lower rectifying tower 3 enters a condensing evaporator 4 at the bottom of the upper rectifying tower, is cooled by the condensing evaporator 4 at the bottom of the upper rectifying tower and then enters a reflux tank 5 at the top of the lower rectifying tower, and liquid coming out of the bottom of the reflux tank 5 at the top of the lower rectifying tower enters the top of the lower rectifying tower 3 and serves as reflux liquid of the lower rectifying tower 3; gas coming out of the top of a reflux tank 5 at the top of a lower tower of the rectifying tower enters from the middle of an upper tower 6 of the rectifying tower after the pressure is controlled by a regulating valve, and light components such as nitrogen, oxygen, hydrogen and the like are removed by rectification in the upper tower 6 of the rectifying tower;
step four: liquid discharged from the bottom of the upper tower 6 of the rectifying tower is high-purity liquid methane, and is subcooled by a channel D of the heat exchanger 10 and then is stored in an external storage tank as a high-purity liquid methane product; gas coming out of the top of the upper tower 6 of the rectifying tower enters a condensing heat exchanger 7 at the top of the upper tower of the rectifying tower, is cooled by the condensing heat exchanger 7 at the top of the upper tower of the rectifying tower and then enters a reflux tank 8 at the top of the upper tower of the rectifying tower, and liquid coming out of the bottom of the reflux tank 8 at the top of the upper tower of the rectifying tower enters from the top of the upper tower 6 of the rectifying tower and participates in rectification as reflux liquid of the upper tower 6 of the rectifying tower; and the gas coming out of the top of the reflux tank 8 at the top of the upper tower of the rectifying tower enters a channel E of a heat exchanger 10 for reheating, and is used as purge gas to go out after reheating.
In the embodiment, the cold quantity required by the heat exchanger 10 and the cold quantity required by the condensing heat exchanger 7 on the top of the upper tower of the rectifying tower are provided by closed-type cryogen first-stage throttling refrigeration; the circulating refrigeration method comprises the following steps: the refrigerant is pressurized by a refrigerant compressor 9 and then enters a channel C of a heat exchanger 10 for precooling, the refrigerant is precooled to a certain temperature and then comes out of the channel C, the refrigerant coming out enters a condensation evaporator 4 at the bottom of the upper tower of the rectifying tower and is cooled and liquefied by the condensation evaporator 4 at the bottom of the upper tower of the rectifying tower, and ascending steam stripping is provided for the upper tower 6 of the rectifying tower; liquid refrigerant coming out of the condensation evaporator 4 at the bottom of the upper tower of the rectifying tower enters the condensation heat exchanger 7 at the top of the upper tower of the rectifying tower after the pressure is controlled by a regulating valve, so that a cold source is provided for the condensation heat exchanger 7 at the top of the upper tower of the rectifying tower; gas refrigerant coming out of the condensing heat exchanger 7 at the top of the rectifying tower enters a channel B of the heat exchanger 10 to provide cooling capacity for the heat exchanger 10, and the gas refrigerant after being reheated by the heat exchanger 10 enters a refrigerant compressor 9 to realize the circulating compression throttling refrigeration of the refrigerant.
In addition, it should be noted that the specific embodiments described in the present specification may be different in the components, the shapes of the components, the names of the components, and the like, and the above described contents are merely illustrative of the structures of the present invention. All equivalent or simple changes in the structure, characteristics and principles of the invention are included in the protection scope of the patent. Various modifications, additions and substitutions for the specific embodiments described may be made by those skilled in the art without departing from the scope of the invention as defined in the accompanying claims.
Claims (9)
1. A method for extracting and liquefying high-purity methane by using liquefied natural gas is implemented by adopting a high-purity methane extraction and liquefaction system, wherein the high-purity methane extraction and liquefaction system comprises an LNG buffer tank (1), an LNG transfer pump (2), a lower rectifying tower (3), an upper rectifying tower bottom condensation evaporator (4), an upper rectifying tower (6), an upper rectifying tower top condensation heat exchanger (7), a lower rectifying tower top reflux tank (5), an upper rectifying tower top reflux tank (8) and a heat exchanger (10), and the heat exchanger (10) is provided with a channel A, a channel D and a channel E; the method is characterized in that: the method for extracting and liquefying high-purity methane by using liquefied natural gas comprises the following steps:
the method comprises the following steps: liquefied natural gas enters an LNG buffer tank (1), the liquefied natural gas in the LNG buffer tank (1) is pressurized through an LNG transfer pump (2), the pressurized liquefied natural gas enters a channel A of a heat exchanger (10) to be heated and gasified, and gasified gaseous natural gas comes out from the channel A;
step two: the gaseous natural gas from the channel A enters the bottom of a lower tower (3) of the rectifying tower, steam stripping rectification is carried out in the lower tower (3) of the rectifying tower, alkane heavy components are separated out, the separated alkane heavy components enter a channel E of a heat exchanger (10) after coming out from the bottom of the lower tower (3) of the rectifying tower for rewarming, and the reheated alkane heavy components are taken as purge gas to be discharged out of the world;
step three: gas coming out of the upper part of the lower rectifying tower (3) enters an upper rectifying tower bottom condensation evaporator (4), is cooled by the upper rectifying tower bottom condensation evaporator (4) and then enters a lower rectifying tower top reflux tank (5), and liquid coming out of the bottom of the lower rectifying tower top reflux tank (5) enters the top of the lower rectifying tower (3) and serves as reflux liquid of the lower rectifying tower (3); gas coming out of the top of a reflux tank (5) at the top of the lower tower of the rectifying tower enters from the middle of an upper tower (6) of the rectifying tower after the pressure is controlled by a regulating valve, and is rectified and removed of light components inside the upper tower (6) of the rectifying tower;
step four: liquid discharged from the bottom of the upper tower (6) of the rectifying tower is high-purity liquid methane, and is subcooled by a channel D of the heat exchanger (10) and then is stored in an external storage tank as a high-purity liquid methane product; gas coming out of the top of the upper tower (6) of the rectifying tower enters a condensing heat exchanger (7) at the top of the upper tower of the rectifying tower, is cooled by the condensing heat exchanger (7) at the top of the upper tower of the rectifying tower and then enters a reflux tank (8) at the top of the upper tower of the rectifying tower, and liquid coming out of the bottom of the reflux tank (8) at the top of the upper tower of the rectifying tower enters the top of the upper tower (6) of the rectifying tower and participates in rectification as reflux liquid of the upper tower (6) of the rectifying tower; and the gas coming out from the top of the reflux tank (8) at the top of the upper tower of the rectifying tower enters a channel E of a heat exchanger (10) for reheating, and is used as purge gas to be discharged outside after reheating.
2. The method for extracting and liquefying high-purity methane by using liquefied natural gas according to claim 1, wherein the method comprises the following steps: the high-purity methane extraction and liquefaction system further comprises a refrigerant compressor (9), and the heat exchanger (10) is also provided with a channel B and a channel C; the refrigerant outlet of the refrigerant compressor (9) is communicated with the inlet end of the channel C through a first refrigerant circulating pipeline (25), the outlet end of the channel C is communicated with the refrigerant inlet of the condensation evaporator (4) at the bottom of the rectifying tower upper tower through a second refrigerant circulating pipeline (26), the refrigerant outlet of the condensation evaporator (4) at the bottom of the rectifying tower upper tower is communicated with the refrigerant inlet of the condensation heat exchanger (7) at the top of the rectifying tower upper tower through a third refrigerant circulating pipeline (27), the refrigerant outlet of the condensation heat exchanger (7) at the top of the rectifying tower upper tower is communicated with the inlet end of the channel B through a fourth refrigerant circulating pipeline (28), and the outlet end of the channel B is communicated with the refrigerant inlet of the refrigerant compressor (9) through a fifth refrigerant circulating pipeline (29).
3. The method for extracting and liquefying high-purity methane by using liquefied natural gas as claimed in claim 2, wherein the method comprises the following steps: the cold energy required by the heat exchanger (10) and the cold energy required by the condensing heat exchanger (7) on the top of the upper tower of the rectifying tower are provided by closed cryogen first-stage throttling refrigeration;
the circulating refrigeration method comprises the following steps: the refrigerant is pressurized by a refrigerant compressor (9) and then enters a channel C of a heat exchanger (10) for precooling, the refrigerant is precooled to a certain temperature and then comes out of the channel C, the refrigerant coming out enters a condensation evaporator (4) at the bottom of the upper tower of the rectifying tower, and is cooled and liquefied by the condensation evaporator (4) at the bottom of the upper tower of the rectifying tower, so that ascending steam stripping is provided for the upper tower (6) of the rectifying tower; liquid refrigerant coming out of the condensation evaporator (4) at the bottom of the upper tower of the rectifying tower enters a condensation heat exchanger (7) at the top of the upper tower of the rectifying tower after the pressure is controlled by a regulating valve, so that a cold source is provided for the condensation heat exchanger (7) at the top of the upper tower of the rectifying tower; gas refrigerant coming out of the condensing heat exchanger (7) at the top of the upper tower of the rectifying tower enters a channel B of the heat exchanger (10) to provide cold energy for the heat exchanger (10), and the gas refrigerant after being reheated by the heat exchanger (10) enters a refrigerant compressor (9) to realize the circulating compression throttling refrigeration of the refrigerant.
4. The method for extracting and liquefying high-purity methane by using liquefied natural gas according to claim 1, wherein the method comprises the following steps: the lower rectifying tower (3), the condensing evaporator (4) at the bottom of the upper rectifying tower, the upper rectifying tower (6) and the condensing heat exchanger (7) at the top of the upper rectifying tower are arranged from bottom to top;
the LNG buffer tank (1) is used for storing liquefied natural gas, the LNG buffer tank (1) is communicated with the inlet end of the channel A through a first pipeline (11), the LNG transfer pump (2) is installed on the first pipeline (11), and the outlet end of the channel A is communicated with the middle air inlet of the lower tower (3) of the rectifying tower through a second pipeline (12);
an air outlet at the upper part of the lower rectifying tower (3) is communicated with an air inlet of a condensation evaporator (4) at the bottom of the upper rectifying tower through a third pipeline (13); a liquid outlet of the condensation evaporator (4) at the bottom of the upper tower of the rectifying tower is communicated with a liquid inlet of the reflux tank (5) at the top of the lower tower of the rectifying tower through a fourth pipeline (14);
a liquid outlet at the bottom of the reflux tank (5) at the top of the lower rectifying tower is communicated with a reflux inlet of the lower rectifying tower (3) through a fifth pipeline (15), and a gas outlet at the top of the reflux tank (5) at the top of the lower rectifying tower is communicated with a middle inlet of the upper rectifying tower (6) through a sixth pipeline (16);
a liquid outlet at the bottom of the upper tower (6) of the rectifying tower is communicated with the inlet end of the channel D through a No. seven pipeline (17), and the outlet end of the channel D is communicated with a high-purity liquid methane product conveying pipeline (18); an air outlet at the upper part of the upper tower (6) of the rectifying tower is communicated with an air inlet of a condensing heat exchanger (7) at the top of the upper tower of the rectifying tower through an eighth pipeline (19);
a liquid outlet of the condensation heat exchanger (7) at the top of the upper tower of the rectifying tower is communicated with a liquid inlet of a reflux tank (8) at the top of the upper tower of the rectifying tower through a ninth pipeline (20), a liquid outlet at the bottom of the reflux tank (8) at the top of the upper tower of the rectifying tower is communicated with a reflux inlet of an upper tower (6) of the rectifying tower through a tenth pipeline (21), a top gas outlet of the reflux tank (8) at the top of the upper tower of the rectifying tower is communicated with an inlet end of a channel E through an eleventh pipeline (22), and an outlet end of the channel E is communicated with a purge gas output pipeline (23); the bottom outlet of the lower rectifying tower (3) is communicated with the inlet end of the channel E through a No. twelve pipeline (24).
5. The method for extracting and liquefying high-purity methane by using liquefied natural gas according to claim 1, wherein the method comprises the following steps: the LNG transfer pump (2) adopts a centrifugal pump.
6. The method for extracting and liquefying high-purity methane by using liquefied natural gas according to claim 1, wherein the method comprises the following steps: the heat exchanger (10) adopts an aluminum plate-fin heat exchanger.
7. The method for extracting and liquefying high-purity methane by using liquefied natural gas according to claim 1, wherein the method comprises the following steps: the condensing evaporator (4) at the bottom of the upper tower part of the rectifying tower is an immersed plate-fin heat exchanger with two heat flows.
8. The method for extracting and liquefying high-purity methane by using liquefied natural gas according to claim 1, wherein the method comprises the following steps: the condensing heat exchanger (7) at the top of the rectifying tower is an immersed plate-fin heat exchanger with a strand of heat flow.
9. The method for extracting and liquefying high-purity methane by using liquefied natural gas according to claim 1, wherein the method comprises the following steps: the packing of the upper tower (6) of the rectifying tower adopts aluminum corrugated regular packing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210108138.8A CN114440552B (en) | 2022-01-28 | 2022-01-28 | Method for extracting and liquefying high-purity methane by using liquefied natural gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210108138.8A CN114440552B (en) | 2022-01-28 | 2022-01-28 | Method for extracting and liquefying high-purity methane by using liquefied natural gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114440552A true CN114440552A (en) | 2022-05-06 |
| CN114440552B CN114440552B (en) | 2024-04-19 |
Family
ID=81372255
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210108138.8A Active CN114440552B (en) | 2022-01-28 | 2022-01-28 | Method for extracting and liquefying high-purity methane by using liquefied natural gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114440552B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110230915A (en) * | 2019-06-17 | 2019-09-13 | 合肥万豪能源设备有限责任公司 | A kind of liquefied natural gas ice chest pre-cooler |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19906602A1 (en) * | 1999-02-17 | 2000-08-24 | Linde Ag | Production of pure methane comprises rectifying liquefied methane from a natural gas storage tank |
| RU2296922C1 (en) * | 2006-03-31 | 2007-04-10 | ООО Производственный кооператив Научно-производственная фирма "ЭКИП" | Method for producing pure methane |
| CN203949442U (en) * | 2014-07-09 | 2014-11-19 | 吴启 | Methane gas recovery device of liquefied |
| CN106979666A (en) * | 2017-04-19 | 2017-07-25 | 苏州市兴鲁空分设备科技发展有限公司 | Methane purifying plant |
-
2022
- 2022-01-28 CN CN202210108138.8A patent/CN114440552B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19906602A1 (en) * | 1999-02-17 | 2000-08-24 | Linde Ag | Production of pure methane comprises rectifying liquefied methane from a natural gas storage tank |
| RU2296922C1 (en) * | 2006-03-31 | 2007-04-10 | ООО Производственный кооператив Научно-производственная фирма "ЭКИП" | Method for producing pure methane |
| CN203949442U (en) * | 2014-07-09 | 2014-11-19 | 吴启 | Methane gas recovery device of liquefied |
| CN106979666A (en) * | 2017-04-19 | 2017-07-25 | 苏州市兴鲁空分设备科技发展有限公司 | Methane purifying plant |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110230915A (en) * | 2019-06-17 | 2019-09-13 | 合肥万豪能源设备有限责任公司 | A kind of liquefied natural gas ice chest pre-cooler |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114440552B (en) | 2024-04-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10578354B2 (en) | Systems and methods for the production of liquefied nitrogen using liquefied natural gas | |
| CN107014151B (en) | Device and method for liquefying hydrogen | |
| US9506690B2 (en) | Process for the production of a subcooled liquefied natural gas stream from a natural gas feed stream, and associated installation | |
| CN113776275B (en) | Hydrogen liquefaction method under LNG cold energy precooling | |
| MX2010010706A (en) | Methods and configuration of boil-off gas handling in lng regasification terminals. | |
| CN112361712A (en) | Hydrogen liquefaction equipment adopting helium refrigeration cycle system | |
| US20090249829A1 (en) | Method for selective extraction of natural gas liquids from "rich" natural gas | |
| US8671715B2 (en) | He-3 recovery from natural helium by distillation | |
| CN114440552B (en) | Method for extracting and liquefying high-purity methane by using liquefied natural gas | |
| CN103542692B (en) | Based on the Unconventional forage liquefaction system of wrap-round tubular heat exchanger | |
| CN104807287A (en) | Small natural gas liquefaction and refrigeration system and small natural gas liquefaction and refrigeration method | |
| CN202813975U (en) | Unconventional natural gas liquefaction system based on winding tubular heat exchanger | |
| CN102628634B (en) | Ternary-cycle cascade refrigeration natural gas liquefaction system and method thereof | |
| CN214095167U (en) | Hydrogen liquefaction equipment adopting helium refrigeration cycle system | |
| CN216845327U (en) | System for utilize liquefied natural gas to carry out high-purity methane and draw liquefaction | |
| CN103322769A (en) | Cascade connecting type liquidizing system of base load type natural gas liquefaction factories | |
| JP2019094950A (en) | Bog re-condensation device and lng storage system provided with the same | |
| CN205090721U (en) | Four component cryogens high pressure throttle refrigerating fluid ization natural gas system | |
| US8991208B2 (en) | Liquefaction process producing subcooled LNG | |
| CN208520082U (en) | A kind of air liquefaction plant | |
| CN101625191B (en) | Low-temperature gas liquefaction and separation system applying effect of segregation | |
| CN205593289U (en) | Liquefied natural gas's device | |
| CN211977383U (en) | Helium liquefying and helium cold source supply device with different temperature grades | |
| US8683825B2 (en) | He-3 recovery from natural helium by distillation | |
| CN205718201U (en) | The natural gas liquefaction system of mix refrigerant pre-cooling nitrogen expansion |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |