A natural gas component separation system

Abstract

The utility model relates to natural gas component separation technical field, specifically disclose a kind of natural gas component separation system, including normal temperature compressor, the normal temperature compressor is oil-free centrifugal compressor, normal temperature compressor uses gas bearing support, the outlet end of normal temperature compressor is connected cooler inlet by pipeline, the cooler connection outlet is connected with No. 1 gas-liquid separator inlet, the liquid outlet of No. 1 gas-liquid separator is connected with heavy hydrocarbon storage tank, the gas outlet of No. 1 gas-liquid separator is connected with the inlet of No. 1 three-way valve.This natural gas component separation system sets multiple gas-liquid separators, can be separated heavy hydrocarbon, light hydrocarbon, LNG, liquid neon, liquid hydrogen, liquid helium and other multiple components in turn according to the different boiling point of gas, and store them in corresponding storage tank respectively, realize the efficient separation and recycling of multiple valuable components in natural gas.

Description

Technical Field

[0001] This utility model relates to the field of natural gas component separation technology, specifically a natural gas component separation system. Background Technology

[0002] Natural gas is a clean and efficient energy source, mainly composed of hydrocarbons such as methane, ethane, and propane, as well as non-hydrocarbon gases such as nitrogen and carbon dioxide. Different applications have different requirements for the purity of natural gas components. For example, as a city gas source, it is necessary to precisely control the methane content and impurity ratio to ensure combustion efficiency and safety. In chemical production, such as when natural gas is used as a raw material to synthesize chemicals, the purity of specific hydrocarbon components directly affects product quality and production efficiency. Therefore, separating the components of natural gas can enhance its utilization value and meet diverse industrial needs.

[0003] Traditional cryogenic distillation technology utilizes the differences in boiling points of various components to gradually condense and fractionate natural gas in a low-temperature environment. However, it involves large equipment, high construction costs, requires maintaining extremely low temperatures during operation, consumes a huge amount of energy, and has stringent requirements for the insulation performance and cryogenic materials of the equipment. Therefore, it suffers from problems such as low separation efficiency, high energy consumption, complex equipment, and poor adaptability. Utility Model Content

[0004] The purpose of this invention is to provide a natural gas component separation system. This system is equipped with multiple gas-liquid separators to separate various components in natural gas, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a natural gas component separation system, comprising an ambient temperature compressor, wherein the ambient temperature compressor is an oil-free centrifugal compressor supported by a gas bearing, the outlet end of the ambient temperature compressor is connected to the inlet of a cooler via a pipeline, the outlet of the cooler is connected to the inlet of a first gas-liquid separator, the liquid outlet of the first gas-liquid separator is connected to a heavy hydrocarbon storage tank, the gas outlet of the first gas-liquid separator is connected to the inlet of a first three-way valve, one outlet of the first three-way valve is connected to one inlet of a first turboexpander, one outlet of the first turboexpander is connected to one side inlet of a fifth heat exchanger, the other side inlet of the first turboexpander is connected to the other outlet of the first three-way valve, and the other outlet of the first turboexpander is connected to the inlet of a second gas-liquid separator.

[0006] Preferably, the liquid outlet of the No. 2 gas-liquid separator is connected to a light hydrocarbon storage tank; the gas outlet of the No. 2 gas-liquid separator is connected to the inlet of a throttle valve; the outlet of the throttle valve is connected to the inlet of the No. 3 gas-liquid separator; the liquid outlet of the No. 3 gas-liquid separator is connected to an LNG storage tank; the LNG storage tank is connected to a No. 4 gas buffer tank; the No. 4 gas buffer tank is connected to the No. 2 heat exchanger and then to the other inlet of the No. 5 heat exchanger; both outlets of the No. 5 heat exchanger are connected to the inlet pipes of the first turbine expander; the gas outlet of the No. 3 gas-liquid separator is connected to the inlet of the No. 2 three-way valve; the gas in the No. 4 gas buffer tank is the BOG flash vapor from the LNG storage tank; and the cooling source for the No. 2 and No. 5 heat exchangers is the BOG flash vapor from the No. 4 gas buffer tank.

[0007] Using the above technical solution, the LNG components in natural gas can be separated through the No. 3 gas-liquid separator.

[0008] Preferably, one outlet of the No. 2 three-way valve is connected to the No. 1 gas buffer tank, the other outlet of the No. 2 three-way valve is connected to the inlet of the No. 2 gas buffer tank, the outlet of the No. 2 gas buffer tank is connected to the No. 1 gas buffer tank, and the No. 1 gas buffer tank is connected to the inlet of the No. 3 three-way valve.

[0009] By adopting the above technical solution, the pressure fluctuations within the system can be balanced through the No. 1 gas buffer tank and the No. 2 gas buffer tank.

[0010] Preferably, one outlet of the No. 3 three-way valve is connected to the inlet of the automatic control valve, the other outlet of the No. 3 three-way valve is connected to one side inlet of the No. 1 heat exchanger, one side outlet of the No. 1 heat exchanger is connected to the automatic control valve, the outlet of the automatic control valve is connected to the inlet of the cryogenic compressor, the outlet of the cryogenic compressor is connected to the other side inlet of the No. 1 heat exchanger, the other side outlet of the No. 1 heat exchanger is connected to one side inlet of the No. 2 heat exchanger, and one side outlet of the No. 2 heat exchanger is connected to the inlet of the No. 4 gas-liquid separator.

[0011] By adopting the above technical solution, the flow rate can be adjusted in real time according to the fluctuation of the raw gas composition through the automatic control valve, so as to maintain the stable operation of the system.

[0012] Preferably, the liquid outlet of the fourth gas-liquid separator is connected to a liquid neon storage tank; the gas outlet of the fourth gas-liquid separator is connected to one side inlet of the third heat exchanger; one side outlet of the third heat exchanger is connected to the inlet of the fifth gas-liquid separator; the liquid outlet of the fifth gas-liquid separator is connected to a liquid hydrogen storage tank; the gas outlet of the fifth gas-liquid separator is connected to one side inlet of the fourth heat exchanger; one side outlet of the fourth heat exchanger is connected to the inlet of the sixth gas-liquid separator; the liquid outlet of the sixth gas-liquid separator is connected to a liquid helium storage tank; the gas outlet of the sixth gas-liquid separator is connected to the inlet of the second turbine expander; and the outlet of the second turbine expander is connected sequentially to the fourth, third, and second heat exchangers before being connected to the third gas buffer tank.

[0013] By adopting the above technical solution, through the series connection of gas-liquid separator No. 4, gas-liquid separator No. 5 and gas-liquid separator No. 6, liquid neon, liquid hydrogen and liquid helium can be separated and stored in sequence.

[0014] Preferably, valves are installed in the pipelines of the system, and the valves are respectively installed at the outlet end of the ambient temperature compressor, the outlet end and the inlet end of the cooler and other components.

[0015] By adopting the above technical solution, the flow direction of gas can be flexibly controlled through the valves.

[0016] Compared with the prior art, the beneficial effects of this utility model are: This natural gas component separation system:

[0017] 1. This system is equipped with multiple gas-liquid separators, which can sequentially separate heavy hydrocarbons, light hydrocarbons, LNG, liquid neon, liquid hydrogen, liquid helium and other components according to the different boiling points of the gases, and store them in corresponding storage tanks, thus realizing the efficient separation and recycling of multiple valuable components in natural gas.

[0018] 2. The cooling capacity of the heat exchanger in this system comes from the separated gas stream, making full use of the internal cooling capacity of the system, reducing dependence on external cooling capacity, reducing energy consumption and operating costs, and improving the energy efficiency of the system.

[0019] 3. This system is equipped with multiple gas buffer tanks and valves to store gas streams and balance pressure, ensuring the stable operation of the system. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the system structure of this utility model.

[0021] In the diagram: 1. Ambient temperature compressor; 2. Valve; 3. Cooler; 401. Gas-liquid separator No. 1; 402. Gas-liquid separator No. 2; 403. Gas-liquid separator No. 3; 404. Gas-liquid separator No. 4; 405. Gas-liquid separator No. 5; 406. Gas-liquid separator No. 6; 5. Heavy hydrocarbon storage tank; 6. Three-way valve No. 1; 7. Turbine expander No. 1; 8. Light hydrocarbon storage tank; 9. Throttling valve; 10. LNG storage tank; 11. Three-way valve No. 2. 12. Gas Buffer Tank No. 1; 13. Gas Buffer Tank No. 2; 14. Three-way Valve No. 3; 15. Automatic Control Valve; 16. Cryogenic Compressor; 17. Heat Exchanger No. 1; 18. Heat Exchanger No. 2; 19. Liquid Neon Storage Tank; 20. Heat Exchanger No. 3; 21. Liquid Hydrogen Storage Tank; 22. Heat Exchanger No. 4; 23. Liquid Helium Storage Tank; 24. Second Turbine Expander; 25. Gas Buffer Tank No. 3; 26. Gas Buffer Tank No. 4; 27. Heat Exchanger No. 5.

[0022] Figure 2 This is a schematic diagram of the inlet and outlet of the first turbine expander.

[0023] In the diagram: 701, expansion end inlet; 702, expansion end outlet; 703, booster end inlet; 704, booster end outlet. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Please see Figure 1 This utility model provides a technical solution: a natural gas component separation system, including an ambient temperature compressor 1, valves 2, a cooler 3, a first gas-liquid separator 401, a second gas-liquid separator 402, a third gas-liquid separator 403, a fourth gas-liquid separator 404, a fifth gas-liquid separator 405, a sixth gas-liquid separator 406, a heavy hydrocarbon storage tank 5, a first three-way valve 6, a first turbine expander 7, a light hydrocarbon storage tank 8, a throttle valve 9, and LNG. Storage tank 10, No. 2 three-way valve 11, No. 1 gas buffer tank 12, No. 2 gas buffer tank 13, No. 3 three-way valve 14, automatic control valve 15, cryogenic compressor 16, No. 1 heat exchanger 17, No. 2 heat exchanger 18, liquid neon storage tank 19, No. 3 heat exchanger 20, liquid hydrogen storage tank 21, No. 4 heat exchanger 22, liquid helium storage tank 23, second turbine expander 24, No. 3 gas buffer tank 25, No. 4 gas buffer tank 26, No. 5 heat exchanger 27.

[0026] The ambient temperature compressor 1 is an oil-free centrifugal compressor supported by a gas bearing. The outlet of the ambient temperature compressor 1 is connected to the inlet of the cooler 3 via a pipe. The outlet of the cooler 3 is connected to the inlet of the first gas-liquid separator 401. The liquid outlet of the first gas-liquid separator 401 is connected to the heavy hydrocarbon storage tank 5. The gas outlet of the first gas-liquid separator 401 is connected to the inlet of the first three-way valve 6. One outlet of the first three-way valve 6 is connected to one inlet of the first turboexpander 7. One outlet of the first turboexpander 7 is connected to one side inlet of the fifth heat exchanger 27. The other side inlet of the first turboexpander 7 is connected to the other outlet of the first three-way valve 6. The other outlet of the first turboexpander 7 is connected to the inlet of the second gas-liquid separator 402. The liquid outlet of separator 402 is connected to light hydrocarbon storage tank 8. The gas outlet of the second gas-liquid separator 402 is connected to the inlet of throttle valve 9. The outlet of throttle valve 9 is connected to the inlet of the third gas-liquid separator 403. The liquid outlet of the third gas-liquid separator 403 is connected to LNG storage tank 10. LNG storage tank 10 is connected to the fourth gas buffer tank 26. The fourth gas buffer tank 26 is connected to the second heat exchanger 18 and then to the other side inlet of the fifth heat exchanger 27. Both outlets of the fifth heat exchanger 27 are connected to the inlet pipe of the first turbine expander 7. The gas in the fourth gas buffer tank 26 is the flash vapor BOG in LNG storage tank 10. The cooling source of the second heat exchanger 18 and the fifth heat exchanger 27 is the flash vapor BOG in the fourth gas buffer tank 26.The gas outlet of gas-liquid separator 403 is connected to the inlet of three-way valve 11. One outlet of three-way valve 11 is connected to gas buffer tank 12. The other outlet of three-way valve 11 is connected to the inlet of gas buffer tank 13. The outlet of gas buffer tank 13 is connected to gas buffer tank 12. Gas buffer tank 12 is connected to the inlet of three-way valve 14. One outlet of three-way valve 14 is connected to the inlet of automatic control valve 15. The other outlet of three-way valve 14 is connected to one side inlet of heat exchanger 17. One side outlet of heat exchanger 17 is connected to automatic control valve 15. The outlet of control valve 15 is connected to the inlet of cryogenic compressor 16. The outlet of cryogenic compressor 16 is connected to the other inlet of heat exchanger 17. The other outlet of heat exchanger 17 is connected to one inlet of heat exchanger 18. One outlet of heat exchanger 18 is connected to the inlet of gas-liquid separator 404. The liquid outlet of gas-liquid separator 404 is connected to liquid neon storage tank 19. The gas outlet of gas-liquid separator 404 is connected to one inlet of heat exchanger 20. One outlet of heat exchanger 20 is connected to the inlet of gas-liquid separator 405. The liquid outlet of gas-liquid separator 405 is connected to liquid hydrogen storage tank. Connection 21: The gas outlet of gas-liquid separator 405 (No. 5) is connected to one side inlet of heat exchanger 22 (No. 4); one side outlet of heat exchanger 22 (No. 4) is connected to the inlet of gas-liquid separator 406 (No. 6); the liquid outlet of gas-liquid separator 406 (No. 6) is connected to liquid helium storage tank 23; the gas outlet of gas-liquid separator 406 (No. 6) is connected to the inlet of second turbine expander 24; the outlet of second turbine expander 24 is sequentially connected to heat exchanger 22 (No. 4), heat exchanger 20 (No. 3), and heat exchanger 18 (No. 2), and then connected to gas buffer tank 25 (No. 3). Valves 2 are installed in the pipelines of the system, and valves 2 are respectively located at the outlet end of ambient temperature compressor 1; cooler 3... The outlets and inlets of all other components are connected as follows: one outlet of the No. 1 three-way valve 6 is connected to the expansion end inlet 701 of the first turbine expander 7, the expansion end outlet 702 is connected to the inlet of the No. 2 gas-liquid separator 402, and the other outlet of the No. 1 three-way valve 6 is connected to the booster end inlet 703 of the first turbine expander 7. After being compressed at the booster end, the gas is connected to one side inlet of the No. 5 heat exchanger 27 from the booster end outlet 704. The two gas streams separated by the No. 1 three-way valve flow through the expansion end and the booster end of the first turbine expander 7, respectively. The gas at the expansion end of the first turbine expander 7 does work, which drives the gas at the booster end to do work, thus completing the energy recovery and utilization at the expansion end.

[0027] like Figure 1As shown, the raw gas enters the ambient temperature compressor 1 for compression, and then undergoes preliminary pre-cooling by the cooler 3 to form the first gas stream. The first gas stream passes through the first gas-liquid separator 401 to remove heavy hydrocarbons and forms the second gas stream. The liquid heavy hydrocarbons are stored in the heavy hydrocarbon storage tank 5. The second gas stream is diverted through the first three-way valve 6 and enters the boosting end of the first turbine expander 7. Then, it merges with the second gas stream through the fifth heat exchanger 27. The merged second gas stream enters the expansion end of the first turbine expander 7 and becomes the third gas stream after expansion and cooling. After passing through the second gas-liquid separator 402 to remove light hydrocarbons, it forms the fourth gas stream. The liquid light hydrocarbons are stored in the light hydrocarbon storage tank 8. The fourth gas stream is liquefied by the throttling valve 9 and separated by the third gas-liquid separator 403. The liquid enters the LNG storage tank 10, and the LNG can be output as a finished product. The remaining gas becomes the fifth gas stream and passes through the second three-way valve 11.

[0028] The fifth gas stream contains neon, hydrogen, and helium. Through gas-liquid separators 404, 405, and 406, as well as heat exchangers 18, 20, and 22, liquid neon, liquid hydrogen, and liquid helium are separated sequentially according to their different boiling points and stored in liquid neon tank 19, liquid hydrogen tank 21, and liquid helium tank 23, respectively.

[0029] The expansion working medium at the expansion end of the first turbine expander 7 is the second gas stream, and the compression working medium at the compression end is the second gas split stream. There is no separate external gas supply at the compression end. The energy at the expansion end and the compression end is conserved. A BOG collection pipeline is installed at the upper end of the LNG storage tank 10 to collect BOG. ​​The collected BOG enters the fourth gas buffer tank 26 to provide a cooling source for the fifth heat exchanger 27 and the second heat exchanger 18. After the automatic control valve 15 is opened, the fifth gas stream enters the first gas buffer tank 12 and the second gas buffer tank 13 through the second three-way valve 11. A pipeline and valve 2 are installed between the first gas buffer tank 12 and the second gas buffer tank 13 to balance the pressure between the first gas buffer tank 12 and the second gas buffer tank 13.

[0030] The fifth gas stream is divided into a fifth gas stream and a fifth gas split stream by the three-way valve 14. The fifth gas split stream passes through the first heat exchanger 17, provides a source of cooling for the first heat exchanger 17, and then mixes with the sixth gas. After being compressed by the low-temperature compressor 16, the sixth gas stream is formed. The sixth gas stream passes sequentially through the second heat exchanger 18, the fourth gas-liquid separator 404, the third heat exchanger 20, the fifth gas-liquid separator 405, the fourth heat exchanger 22, the sixth gas-liquid separator 406, and the second turbine expander 24 for liquefaction and separation of gas components.

[0031] Working principle: When using this natural gas component separation system, the raw gas enters the ambient temperature compressor 1 for compression, and then undergoes preliminary pre-cooling through the cooler 3. The gas continues to flow, and heavy hydrocarbons are separated in the first gas-liquid separator 401, with the liquid heavy hydrocarbons entering the heavy hydrocarbon storage tank 5; light hydrocarbons are separated in the second gas-liquid separator 402, and the light hydrocarbons enter the light hydrocarbon storage tank 8; LNG is separated in the third gas-liquid separator 403, and the LNG enters the LNG storage tank 10; liquid neon is separated in the fourth gas-liquid separator 404 and stored in the liquid neon storage tank 19; liquid hydrogen is separated in the fifth gas-liquid separator 405 and stored in the liquid hydrogen storage tank 21; and liquid helium is separated in the sixth gas-liquid separator 406 and stored in the liquid helium storage tank 23. This achieves the separation of different components in natural gas, increasing the overall practicality.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A natural gas component separation system, comprising an ambient temperature compressor (1) and an expansion end outlet (702), characterized in that: The ambient temperature compressor (1) is an oil-free centrifugal compressor. The ambient temperature compressor (1) is supported by a gas bearing. The outlet of the ambient temperature compressor (1) is connected to the inlet of the cooler (3) through a pipe. The outlet of the cooler (3) is connected to the inlet of the first gas-liquid separator (401). The liquid outlet of the first gas-liquid separator (401) is connected to the heavy hydrocarbon storage tank (5). The gas outlet of the first gas-liquid separator (401) is connected to the inlet of the first three-way valve (6). One outlet of the first three-way valve (6) is connected to the expansion end inlet of the first turbine expander (7). (701) Connection: The expansion end outlet (702) is connected to the inlet of the second gas-liquid separator (402), and the other outlet of the first three-way valve (6) is connected to the booster end inlet (703) of the first turbine expander (7). After being compressed by the booster end, the booster end outlet (704) is connected to one side inlet of the fifth heat exchanger (27). The two gas streams separated by the first three-way valve flow through the expansion end and the booster end of the first turbine expander (7) respectively. The gas at the expansion end of the first turbine expander (7) does work, which drives the gas at the booster end to do work, thus completing the energy recovery and utilization at the expansion end.

2. The natural gas component separation system according to claim 1, characterized in that: The liquid outlet of the second gas-liquid separator (402) is connected to a light hydrocarbon storage tank (8). The gas outlet of the second gas-liquid separator (402) is connected to the inlet of a throttle valve (9). The outlet of the throttle valve (9) is connected to the inlet of the third gas-liquid separator (403). The liquid outlet of the third gas-liquid separator (403) is connected to an LNG storage tank (10). The LNG storage tank (10) is connected to a fourth gas buffer tank (26). The fourth gas buffer tank (26) is connected to a second heat exchanger (18). After connection, it is connected to the other side inlet of the No. 5 heat exchanger (27). Both sides of the outlet of the No. 5 heat exchanger (27) are connected to the inlet pipe of the first turbine expander (7). The gas outlet of the No. 3 gas-liquid separator (403) is connected to the inlet of the No. 2 three-way valve (11). The gas in the No. 4 gas buffer tank (26) is the flash vapor BOG in the LNG storage tank (10). The cooling source of the No. 2 heat exchanger (18) and the No. 5 heat exchanger (27) is the flash vapor BOG in the No. 4 gas buffer tank (26).

3. A natural gas component separation system according to claim 2, characterized in that: One outlet of the No. 2 three-way valve (11) is connected to the No. 1 gas buffer tank (12), and the other outlet of the No. 2 three-way valve (11) is connected to the inlet of the No. 2 gas buffer tank (13). Valves are installed in the No. 2 gas buffer tank (13) and the No. 1 gas buffer tank (12) to balance the pressure of the two buffer tanks. The No. 1 gas buffer tank (12) is connected to the inlet of the No. 3 three-way valve (14).

4. A natural gas component separation system according to claim 3, characterized in that: One outlet of the No. 3 three-way valve (14) is connected to the inlet of the automatic control valve (15), and the other outlet of the No. 3 three-way valve (14) is connected to one side inlet of the No. 1 heat exchanger (17). One side outlet of the No. 1 heat exchanger (17) is connected to the automatic control valve (15), and the outlet of the automatic control valve (15) is connected to the inlet of the cryogenic compressor (16). The outlet of the cryogenic compressor (16) is connected to the other side inlet of the No. 1 heat exchanger (17), and the other side outlet of the No. 1 heat exchanger (17) is connected to one side inlet of the No. 2 heat exchanger (18). One side outlet of the No. 2 heat exchanger (18) is connected to the inlet of the No. 4 gas-liquid separator (404).

5. A natural gas component separation system according to claim 4, characterized in that: The liquid outlet of the fourth gas-liquid separator (404) is connected to the liquid neon storage tank (19). The gas outlet of the fourth gas-liquid separator (404) is connected to one side inlet of the third heat exchanger (20). One side outlet of the third heat exchanger (20) is connected to the inlet of the fifth gas-liquid separator (405). The liquid outlet of the fifth gas-liquid separator (405) is connected to the liquid hydrogen storage tank (21). The gas outlet of the fifth gas-liquid separator (405) is connected to one side inlet of the fourth heat exchanger (22). Then, one side outlet of the No. 4 heat exchanger (22) is connected to the inlet of the No. 6 gas-liquid separator (406), the liquid outlet of the No. 6 gas-liquid separator (406) is connected to the liquid helium storage tank (23), the gas outlet of the No. 6 gas-liquid separator (406) is connected to the inlet of the second turbine expander (24), and the outlet of the second turbine expander (24) is connected in sequence to the No. 4 heat exchanger (22), the No. 3 heat exchanger (20) and the No. 2 heat exchanger (18) and then connected to the No. 3 gas buffer tank (25).

6. A natural gas component separation system according to claim 1, characterized in that: Valves (2) are installed in the pipelines of the system. The valves (2) are respectively installed at the outlet end of the ambient temperature compressor (1), the outlet end and the inlet end of the cooler (3) and other components.

7. A natural gas component separation system according to claim 5, characterized in that: The cooling capacity of the No. 4 heat exchanger (22), No. 3 heat exchanger (20) and No. 2 heat exchanger (18) comes from the gas after expansion and cooling by the second turbine expander (24).

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