Gas liquefaction method and system

Abstract

The present invention relates to a gas liquefaction system to achieve the purpose of conveniently providing cold energy to liquefy a gas. The gas liquefaction system includes a gas delivery passageway, gas driving equipment and at least two pieces of gas liquefaction equipment that are arranged according to level. The gas driving equipment is configured to drive a gas to enter the gas liquefaction system from the gas inlet end. The gas liquefaction equipment is configured to liquefy the gas in the order of the levels. The gas liquefaction system further includes gasification equipment which is configured, when any arbitrary gas liquefaction equipment of the at least two pieces of gas liquefaction equipment is in need of cold energy for gas liquefaction, to exchange heat with the liquefied gas released from the liquefied gas storage tank that contains already liquefied gas and is associated with a gas liquefaction equipment which is at a level higher than or equal to the level of the arbitrary gas liquefaction equipment, thereby gasifying the liquefied gas released from the liquefied gas storage tank. The gas liquefaction system further includes a cold energy pipeline configured to deliver the cold energy generated by gasification to the arbitrary gas liquefaction equipment, so that the arbitrary gas liquefaction equipment receives the cold energy to exchange the heat generated during gas compression. In addition, the present invention also relates to a gas liquefaction method.

1 . A gas liquefaction system, comprising: a gas delivery passageway, gas driving equipment and at least two pieces of gas liquefaction equipment that are arranged at different levels, wherein the gas driving equipment is arranged at a gas inlet end of the gas delivery passageway, the gas delivery passageway is communicated with gas inlet ends of the at least two pieces of gas liquefaction equipment, and each of the at least two pieces of gas liquefaction equipment is provided with a liquefied gas storage tank respectively;
 wherein the gas driving equipment is configured to drive a gas to enter the gas liquefaction system from the gas inlet end of the gas delivery passageway;   wherein the at least two pieces of gas liquefaction equipment that are arranged at different levels are configured to liquefy the gas that enters the gas liquefaction system from a gas inlet end of the gas liquefaction equipment in an order of the levels,   wherein the liquefied gas obtained by liquefaction enters liquefied gas storage tanks that are configured for the gas liquefaction equipment;   and the gas liquefaction system further comprising:   gasification equipment, configured to, when any arbitrary gas liquefaction equipment of the at least two pieces of gas liquefaction equipment is in need of cold energy for gas liquefaction, exchange heat with the liquefied gas released from a liquefied gas storage tank, the liquefied gas storage tank containing already liquefied gas and being associated with any gas liquefaction equipment which is at a level higher than or equal to the level of the arbitrary gas liquefaction equipment, thereby gasifying the liquefied gas released from the liquefied gas storage tank; and   a cold energy pipeline, which is configured to deliver the cold energy generated by gasification to the arbitrary gas liquefaction equipment, so that the arbitrary gas liquefaction equipment receives the cold energy to exchange the heat generated during gas compression, such that the gas in the arbitrary gas liquefaction equipment reaches or drops below a critical temperature for the liquefaction of the gas through the heat exchange and is therefore liquefied, and the liquefied gas obtained by liquefaction enters the liquefied gas storage tank associated with the arbitrary gas liquefaction equipment.   
     
     
         2 . The gas liquefaction system according to  claim 1 , wherein: for the liquefied gas storage tanks associated with the at least two pieces of gas liquefaction equipment, a gas outlet end of at least one liquefied gas storage tank is communicated with the gasification equipment; and
 the gasification equipment is also configured to gasify the liquefied gas in any arbitrary liquefied gas storage tank that is communicated with the gasification equipment when a wind turbine in a wind field cannot supply sufficient electricity to a power grid; and   the gas liquefaction system further comprising an electric generator configured to be driven by the gas released from the gasification equipment to supply electricity to the power grid.   
     
     
         3 . The gas liquefaction system according to  claim 1 , further comprising: heat insulating pipelines that are communicated with the gas liquefaction equipment and configured to collect heat energy generated during the liquefaction and deliver the heat energy to heat energy storage tanks for storage, so as to provide the heat energy when the gasification equipment performs heat exchange on the liquefied gas. 
     
     
         4 . The gas liquefaction system according to  claim 1 , further comprising: filtration equipment that is arranged for each piece of gas liquefaction equipment respectively and used to separate a gas mixture into pure gases;
 wherein, in an order of the levels from front to back, and starting from a gas inlet of the gas delivery passageway, at least two pieces of gas liquefaction equipment are communicated with the gas delivery passageway through the filtration equipment that is arranged for the gas liquefaction equipment one by one, wherein the gas inlet end of each gas liquefaction equipment is communicated with a separating opening of each filtration equipment that is arranged for the gas liquefaction equipment, and gas inlets of the respective filtration equipment are communicated with the gas delivery passageway;   for the first gas liquefaction equipment that is communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway, the gas inlet of the filtration equipment of the first gas liquefaction equipment is communicated with the gas inlet end of the gas delivery passageway; and as for an arbitrary gas liquefaction equipment except for the first gas liquefaction equipment, the gas inlet of the filtration equipment of the arbitrary gas liquefaction equipment is communicated with a gas outlet of the filtration equipment of the previous gas liquefaction equipment that is arranged before the arbitrary gas liquefaction equipment through the gas delivery passageway;   wherein the filtration equipment is configured to filter the gas that enters the gas liquefaction system from the gas inlets of the filtration equipment, the separated pure gases enter the gas liquefaction equipment from separating openings, and the remaining gases are discharged out of the gas outlets.   
     
     
         5 . The gas liquefaction system according to  claim 4 , wherein: the gas is natural air in a wind field; and
 the at least two pieces of gas liquefaction equipment comprise carbon dioxide liquefaction equipment configured to liquefy carbon dioxide, oxygen liquefaction equipment configured to liquefy oxygen and nitrogen liquefaction equipment configured to liquefy nitrogen, wherein the carbon dioxide liquefaction equipment is the first gas liquefaction equipment communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway, the oxygen liquefaction equipment is the second gas liquefaction equipment communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway, and the nitrogen liquefaction equipment is the third gas liquefaction equipment communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway.   
     
     
         6 . The gas liquefaction system according to  claim 5 , wherein: in terms of the order of levels, the carbon dioxide liquefaction equipment is arranged in front of the oxygen liquefaction equipment and the nitrogen liquefaction equipment, and the oxygen liquefaction equipment is arranged in front of the nitrogen liquefaction equipment;
 wherein the gasification equipment is configured to perform heat exchange on liquefied carbon dioxide released from the liquefied gas storage tank associated with the carbon dioxide liquefaction equipment to gasify the liquefied carbon dioxide when cold energy is needed for the liquefaction of the gas in the oxygen liquefaction equipment;   wherein the cold energy pipeline is configured to deliver to the oxygen liquefaction equipment the cold energy that is generated during the gasification of the liquefied carbon dioxide, so that the oxygen liquefaction equipment receives the cold energy to exchange heat that is generated during oxygen compression, such that the oxygen in the oxygen liquefaction equipment reaches or drops below a critical temperature for the liquefaction of the oxygen and is therefore liquefied; and the liquid oxygen that is obtained from the liquefaction enters the liquefied gas storage tank associated with the oxygen liquefaction equipment;   wherein the gasification equipment is also configured to exchange heat of the liquefied oxygen released from the liquefied gas storage tank that contains liquefied oxygen to gasify the liquefied oxygen when the cold energy generated during the gasification of the liquefied carbon dioxide released from the liquefied gas storage tank associated with the carbon dioxide liquefaction equipment is insufficient; and   wherein the cold energy pipeline is also configured to deliver the cold energy that is generated during the gasification of the liquefied oxygen to the oxygen liquefaction equipment and/or the nitrogen liquefaction equipment, so that the oxygen liquefaction equipment and/or the nitrogen liquefaction equipment receive the cold energy to exchange heat generated during the gas compression, such that the gas in the oxygen liquefaction equipment and/or the nitrogen liquefaction equipment reach or drop below a critical temperature for the liquefaction of the gas, and is therefore liquefied.   
     
     
         7 . The gas liquefaction system according to  claim 1 , wherein: a gas outlet end of the gasification equipment is also communicated with a gas inlet end of gas recycling equipment, the gas recycling equipment is configured to recycle the gas that is discharged out of the gasification equipment, the recycled gas is delivered to gas inlet end(s) of one or more of the at least two pieces gas liquefaction equipment through a gas recycling pipeline, so that the discharged gas returns to the gas liquefaction equipment for liquefaction. 
     
     
         8 . A gas liquefaction method, applicable to a gas liquefaction system that comprises a gas delivery passageway, gas driving equipment and at least two pieces of gas liquefaction equipment that are arranged at different levels, comprising the steps of:
 arranging the gas driving equipment at a gas inlet end of the gas delivery passageway, communicating the gas delivery passageway with gas inlet ends of the at least two pieces of gas liquefaction equipment, and configuring a liquefied gas storage tank for each of the at least two pieces of gas liquefaction equipment respectively;   using the gas driving equipment to drive a gas to enter the gas liquefaction system from the gas inlet end of the gas delivery passageway;   using the at least two pieces of gas liquefaction equipment that are arranged at different levels to liquefy the gas that enters the gas liquefaction system from a gas inlet end of the gas liquefaction equipment in an order of the levels, wherein the liquefied gas obtained by liquefaction enters a designated liquefied gas storage tank associated with the gas liquefaction equipment;   when any arbitrary gas liquefaction equipment of the at least two pieces of gas liquefaction equipment is in need of cold energy for gas liquefaction, using a gasification equipment to exchange heat with the liquefied gas released from the liquefied gas storage tank, the gas storage tank containing already liquefied gas and being associated with any gas liquefaction equipment which is at a level higher than or equal to the level of the gas liquefaction equipment in need of cold energy, thereby gasifying the liquefied gas released from the liquefied gas storage tank; and   using a cold energy pipeline to deliver the cold energy generated by gasification to the arbitrary gas liquefaction equipment, so that the gas liquefaction equipment receives the cold energy to exchange heat generated during gas compression, such that the gas in the gas liquefaction equipment reaches or drops below a critical temperature for the liquefaction of the gas through the heat exchange, and is therefore liquefied, and the liquefied gas obtained by liquefaction enters the liquefied gas storage tank associated with the arbitrary gas liquefaction equipment.   
     
     
         9 . The gas liquefaction method according to  claim 8 , wherein: for the liquefied gas storage tanks associated with the at least two pieces of gas liquefaction equipment, a gas outlet end of at least one liquefied gas storage tank is communicated with the gasification equipment; and
 when a wind turbine in a wind field cannot supply sufficient electricity to a power grid, gasifying the liquefied gas in any arbitrary liquefied gas storage tank that is communicated with the gasification equipment; and   using the gas that is released from the gasification equipment to supply electricity to the power grid.   
     
     
         10 . The gas liquefaction method according to  claim 8 , further comprising the steps of:
 communicating the gas liquefaction equipment with heat insulating pipelines; and   using the heat insulating pipelines to collect heat energy that is generated during the liquefaction and deliver the heat energy to heat energy storage tanks for storage, so as to provide the heat energy when the gasification equipment performs heat exchange on the liquefied gas.   
     
     
         11 . The gas liquefaction method according to  claim 8 , further comprising the steps of:
 arranging a filtration equipment for each piece of gas liquefaction equipment respectively to separate a gas mixture into pure gases;   communicating the at least two pieces of gas liquefaction equipment with the gas delivery passageway through the filtration equipment that is arranged for the gas liquefaction equipment one by one in an order of the levels from front to back and starting from a gas inlet of the gas delivery passageway, wherein the gas inlet end of each gas liquefaction equipment is communicated with a separating opening of each filtration equipment that is arranged for the gas liquefaction equipment, and gas inlets of the respective filtration equipment are communicated with the gas delivery passageway;   for the first gas liquefaction equipment that is communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway, communicating the gas inlet of the filtration equipment of the first gas liquefaction equipment with the gas inlet end of the gas delivery passageway; and as for an arbitrary gas liquefaction equipment except for the first gas liquefaction equipment, communicating the gas inlet of the filtration equipment of the arbitrary gas liquefaction equipment with a gas outlet of the filtration equipment of the previous gas liquefaction equipment that is arranged before the arbitrary gas liquefaction equipment through the gas delivery passageway; and   employing the filtration equipment to filter the gas that enters the gas liquefaction system from the gas inlets of the filtration equipment, wherein the separated pure gases enter the gas liquefaction equipment from separating openings, and the remaining gases are discharged out of the gas outlets.   
     
     
         12 . The gas liquefaction method according to  claim 11 , wherein: the gas is natural air in a wind field; and
 the at least two pieces of gas liquefaction equipment comprise carbon dioxide liquefaction equipment configured to liquefy carbon dioxide, oxygen liquefaction equipment configured to liquefy oxygen and nitrogen liquefaction equipment configured to liquefy nitrogen, wherein the carbon dioxide liquefaction equipment is the first gas liquefaction equipment that is communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway, the oxygen liquefaction equipment is the second gas liquefaction equipment that is communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway, and the nitrogen liquefaction equipment is the third gas liquefaction equipment that is communicated with the gas delivery passageway starting from the gas inlet end of the gas delivery passageway.   
     
     
         13 . The gas liquefaction method according to  claim 12 , wherein: in terms of the order of the levels, the carbon dioxide liquefaction equipment is arranged in front of the oxygen liquefaction equipment and the nitrogen liquefaction equipment, and the oxygen liquefaction equipment is arranged in front of the nitrogen liquefaction equipment;
 wherein the gasification equipment is configured to perform heat exchange on liquefied carbon dioxide released from the liquefied gas storage tank associated with the carbon dioxide liquefaction equipment to gasify the liquefied carbon dioxide when cold energy is required for the liquefaction reaction of the gas in the oxygen liquefaction equipment;   wherein the cold energy pipeline is configured to deliver to the oxygen liquefaction equipment the cold energy that is generated during the gasification of the liquefied carbon dioxide, so that the oxygen liquefaction equipment receives the cold energy to exchange heat that is generated during oxygen compression, such that the oxygen in the oxygen liquefaction equipment reaches or drops below a critical temperature for the liquefaction of the oxygen, and therefore the oxygen is liquefied; and the liquid oxygen that is obtained from the liquefaction reaction enters the liquefied gas storage tank that is configured for the oxygen liquefaction equipment;   wherein the gasification equipment is also configured to exchange heat of the liquefied oxygen released from the liquefied gas storage tank containing liquefied oxygen to gasify the liquefied oxygen when the cold energy that is generated during the gasification of the liquefied carbon dioxide released from the liquefied gas storage tank of the carbon dioxide liquefaction equipment is insufficient; and   wherein the cold energy pipeline is also configured to deliver the cold energy that is generated during the gasification of the liquefied oxygen to the oxygen liquefaction equipment and/or the nitrogen liquefaction equipment, so that the oxygen liquefaction equipment and/or the nitrogen liquefaction equipment obtain(s) the cold energy to exchange heat that is generated during the gas compression, such that the gas in the oxygen liquefaction equipment and/or the nitrogen liquefaction equipment reaches or drops below a critical temperature for the liquefaction of the gas, and is therefore liquefied.   
     
     
         14 . The gas liquefaction method according to  claim 8 , wherein: a gas outlet end of the gasification equipment is also communicated with a gas inlet end of gas recycling equipment; and
 the gas recycling equipment is configured to recycle the gas that is discharged out of the gasification equipment, the recycled gas is delivered to gas inlet end(s) of one or more of the at least two pieces of gas liquefaction equipment through a gas recycling pipeline, so that the discharged gas returns to the gas liquefaction equipment for liquefaction.