High-efficiency cold storage device for LNG

Abstract

The present invention relates to an efficient cold storage device for LNG, which is characterized by comprising a shell, a cold storage material, an LNG solution pump, an LNG inlet valve, and an LNG outlet valve. The inner cavity of the shell is provided with a plurality of mutually interconnected layered shells, and the upper part of each layered shell is provided with mutually interconnected passage openings. The inner cavity formed by the layered shell is provided with cold storage materials, and the cold storage materials are provided with hollow channels. Each hollow channel is connected end to end to form a through channel, and each through channel is respectively connected with a refrigerant solution pump and a refrigerant control valve. An LNG inlet is provided at the bottom of the innermost layered shell, and the LNG inlet is connected with an LNG solution pump and an LNG inlet valve. An LNG outlet is provided on the side wall of the bottom of the shell, and the LNG outlet is connected with an LNG solution pump and an LNG outlet valve. Beneficial effect: In order to effectively utilize the high-quality cold energy resources contained in LNG, the present invention can realize efficient storage of the cold energy contained in LNG.

Description

Technical Field

[0001] The invention belongs to the field of cryogenic engineering, and in particular relates to a high-efficiency cold storage device for LNG. Background Art

[0002] Liquefied natural gas (LNG) is a clean energy that contains a lot of cold energy. At present, the use and attention of LNG are becoming more and more. For the related use of LNG, whether it is in the process of delivering it to users for combustion, or in the process of using it as a power fuel for vehicles and other means of transportation after LNG processing, the first thing to do is to gasify LNG and turn it into gas before using it. Since LNG has an extremely low temperature of about -162℃, the temperature when it is used in gaseous state is much higher than this temperature. In this stage of change, huge cold energy is contained. If this part of cold energy cannot be used well, it will often cause a large waste of resources.

[0003] In the process of LNG gasification, due to the ultra-low temperature characteristics of LNG, if heat is directly exchanged through heat exchange equipment, it will often cause serious damage to the heat exchange equipment, causing the heat exchange equipment to fail to work normally; among the known devices that can use phase change to store cold, some cold storage devices can only meet the short-term cold supply work. At the same time, for vehicles that use LNG as a power fuel, due to factors such as vehicle operation conditions, LNG gasification will be discontinuous, which is not conducive to LNG refrigerated and frozen vehicles that need to adjust the temperature and require continuous cold supply.

[0004] The recovery and utilization of cold energy from LNG gasification is a topic worth exploring and practicing. Patent document publication number 209706401U discloses an LNG cooling adaptive system with a cold storage device, characterized in that it includes an upstream LNG gasification unit and an energy conversion unit, wherein the upstream LNG gasification unit is connected in sequence by a LNG storage tank, an LNG pump, an LNG control valve, an inlet a and an outlet b of the first heat exchanger through pipelines to form a gasification circuit; the energy conversion unit is connected in sequence by an outlet c of the first heat exchanger, an inlet e and an outlet f of the second heat exchanger, a high-temperature coolant storage tank, a coolant pump and an inlet d of the first heat exchanger through pipelines to form a circulation circuit; The first heat exchanger is used to transfer the cold energy released by LNG gasification to the refrigerant; the second heat exchanger is used to transfer the cold energy between the cooled refrigerant and the cold phase of the downstream refrigeration system; the energy conversion unit also includes a cold storage component, which is sequentially connected by pipelines through a low-temperature refrigerant inlet valve, a low-temperature refrigerant storage tank and a low-temperature refrigerant discharge valve to form a cold storage branch, the inlet end of the cold storage branch is connected to the pipeline between the outlet c of the first heat exchanger and the inlet e of the second heat exchanger, and the outlet end of the cold storage branch is connected to the pipeline between the outlet of the high-temperature refrigerant storage tank and the refrigerant pump. Patent document publication number 103017434A discloses a cold storage device matched with an LNG gasification heat exchange system, wherein the LNG gasification heat exchange system includes an LNG inlet, a low-temperature stop valve a, a plate heat exchanger, a low-temperature stop valve b, an air-temperature vaporizer and an LNG outlet and are connected in series through pipelines, a temperature sensor is provided on the connecting pipeline between the plate heat exchanger and the low-temperature stop valve b, and a low-temperature regulating valve is provided on the pipeline connected in parallel with the connecting pipeline between the plate heat exchanger and the low-temperature stop valve b, and is characterized in that: the cold storage device includes a cold storage tank and a circulating water pump and forms a circulating pipeline with the heat exchange tubes in the plate heat exchanger through pipelines, and the cold storage tank is provided with a circulating cold liquid inlet and a circulating cold liquid outlet. Patent document publication number 204895033U discloses a liquefied natural gas vehicle cold energy recovery air conditioning system, characterized in that it includes a gas cylinder, a cold energy recovery exchanger, a water pump, a heater assembly, a cold storage device, a heater and an engine; the gas cylinder is connected to the air inlet end of the cold energy recovery exchanger; the water pump is connected to the water inlet end of the cold energy recovery exchanger; the cold storage device is connected to the water outlet end of the cold energy recovery exchanger, and the heater is connected to the air outlet end of the cold energy recovery exchanger; one end interface of the heater assembly is connected to the water pump, and the other end interface of the heater assembly is connected to the cold storage device; the heater is connected to the fuel air inlet of the engine.

[0005] Based on the above situation, in order to solve the above problems, in order to store the cold energy generated by LNG first, effectively utilize the cold energy contained in the process of LNG becoming gaseous, and be able to achieve a longer period of cold supply, an efficient cold storage device for LNG is needed. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the above-mentioned technology and to provide a highly efficient cold storage device for LNG, which is a highly efficient and convenient device capable of recycling the cold energy in LNG and storing this part of the cold energy in a cold storage material.

[0007] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: an efficient cold storage device for LNG, characterized in that it includes a shell, a cold storage material, an LNG inlet valve, an LNG outlet valve, a first LNG solution pump, a second LNG solution pump, a first refrigerant solution pump, a first refrigerant control valve, a second refrigerant solution pump, a second refrigerant control valve, a third refrigerant solution pump, and a third refrigerant control valve, wherein the inner cavity of the shell is provided with a plurality of mutually interconnected layered shells, and the upper part of each layered shell is provided with mutually interconnected passage openings, and the inner cavity formed by each layered shell is provided with a plurality of mutually interconnected passage openings, and the inner cavity formed by each layered shell is provided with a plurality of mutually interconnected passage openings, and the inner cavity formed by each layered shell is provided with a plurality of mutually interconnected passage openings, and the inner cavity formed by each layered shell is provided with a plurality of mutually interconnected passage openings, and the inner cavity formed by each layered shell is provided with a plurality of mutually interconnected passage openings, and the inner cavity formed by each layered shell is provided with a plurality of mutually interconnected layered shell ... A cold storage material is arranged, and a coil-type cylindrical hollow channel is arranged in the cold storage material. Each hollow channel is connected end to end to form a through channel that is interconnected as a whole and has only one inlet and one outlet suitable for the flow of coolant. Each through channel is respectively connected to a coolant solution pump and a coolant control valve. An LNG inlet is arranged at the bottom of the innermost layered shell, and the LNG inlet is connected to a first LNG solution pump and an LNG inlet valve through a pipeline. An LNG outlet is arranged on the side wall of the bottom of the shell, and the LNG outlet is connected to a second LNG solution pump and an LNG outlet valve through a pipeline.

[0008] The inner cavity of the shell is set as an inner, middle and outer three-layered shell, and cold storage materials are respectively placed in the cavities of the inner, middle and outer three-layered shell. A hollow channel is provided in the cold storage material. The inlet pipe section of the hollow channel is respectively connected to the first refrigerant solution pump and the first refrigerant control valve, the second refrigerant solution pump and the second refrigerant control valve, the third refrigerant solution pump and the third refrigerant control valve, and the hollow channel is filled with refrigerant.

[0009] The height of the passage opening is set to be the highest in the innermost layer and becomes lower layer by layer from the inside to the outside.

[0010] The inner cavity of the shell is set as an inner, middle and outer three-layered shell, and cold storage materials are respectively placed in the cavities of the inner, middle and outer three-layered shell. A hollow channel is provided in the cold storage material. The inlet pipe section of the hollow channel is respectively connected to the first refrigerant solution pump and the first refrigerant control valve, the second refrigerant solution pump and the second refrigerant control valve, the third refrigerant solution pump and the third refrigerant control valve, and the hollow channel is filled with refrigerant.

[0011] Beneficial effects: Compared with the prior art, the present invention can achieve efficient storage of the cold energy contained in LNG in order to effectively utilize the high-quality cold energy resources contained in LNG. The cold energy in LNG is first stored in the cold storage material, and then the cold energy is brought to the required place for work through the coolant flowing through the through channel, and ethylene glycol solution or salt solution can be selected as the coolant for subsequent work according to the amount of cold energy stored in the cold storage material placed in the inner, middle and outer three-layer cavity. Through the operation of this device, the high-quality cold energy contained in LNG can be effectively utilized. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structural cross section of the present invention;

[0013] FIG2( a ) is a schematic diagram of the structure of the hollow channel inside the cold storage material;

[0014] FIG2( b ) is a schematic diagram of the structure of the innermost layer of cold storage material and the hollow channel;

[0015] FIG2(c) is a schematic diagram of the structure of the middle layer, the outermost layer of cold storage material and the hollow channel;

[0016] Figure 3 It is a cross-sectional view of the shell and insulation material.

[0017] In the figure: 1. LNG inlet valve, 2. first LNG solution pump, 3. second LNG solution pump, 4. LNG outlet valve, 5. first refrigerant solution pump, 6. first refrigerant control valve, 7. second refrigerant solution pump, 8. second refrigerant control valve, 9. third refrigerant solution pump, 10. third refrigerant control valve, 11. thermal insulation material, 12. cold storage material, 13. shell, 13-1, channel port, 14. LNG inlet, 15. LNG outlet, 16. hollow channel. DETAILED DESCRIPTION

[0018] The specific implementation of the present invention is described in detail below in conjunction with preferred embodiments.

[0019] See the accompanying drawings for details. This embodiment provides an efficient cold storage device for LNG, including a shell 13, a cold storage material 12, an LNG inlet valve 1, an LNG outlet valve 4, a first LNG solution pump 2, a second LNG solution pump 3, a first refrigerant solution pump 5, a first refrigerant control valve 6, a second refrigerant solution pump 7, a second refrigerant control valve 8, a third refrigerant solution pump 9, and a third refrigerant control valve 10. The inner cavity of the shell is provided with a plurality of layered shells interconnected to form a plurality of cavities, and the upper part of each layered shell is provided with a channel opening 13-1 interconnected to each other, and the height of the channel opening is set to be the highest in the innermost layer, and the height of the channel opening is lower from the inside to the outside. The cavity of the layered shell is provided with a cold storage material 12, and a coil-type cylindrical hollow channel 16 is provided inside the cold storage material 12. The hollow channels are connected end to end to form a through channel that is interconnected as a whole and has only one inlet and one outlet suitable for the flow of coolant. Each through channel is respectively connected to a coolant solution pump and a coolant control valve. An LNG inlet 14 is provided at the bottom of the innermost layered shell, and the LNG inlet is connected to a first LNG solution pump and an LNG inlet valve through a pipeline. An LNG outlet 15 is provided on the side wall of the bottom of the shell, and the LNG outlet is connected to a second LNG solution pump and an LNG outlet valve through a pipeline. The shell and the layered shell are coated with a thermal insulation material layer 11.

[0020] The preferred solution of this embodiment is that the inner cavity of the shell is configured as three layers, namely, inner, middle and outer layers; cold storage materials 12 are respectively placed in the inner, middle and outer cavities; a hollow channel 16 is provided in the cold storage material 12; the inlet pipe section of the coolant in the hollow channel is respectively connected to the first coolant solution pump 5 and the first coolant control valve 6, the second coolant solution pump 7 and the second coolant control valve 8, the third coolant solution pump 9 and the third coolant control valve 10; and coolant is built in the hollow channel.

[0021] Working process

[0022] The overall design of the cold storage device is a rectangular device, and the overall assembly process is as follows: first, the shell and the layered shell are put together according to size, and are installed from the inside to the outside in the order of cold storage material, layered shell, cold storage material, layered shell, cold storage material, and shell. Holes are punched at the corresponding pipeline and channel openings of the shell, and the outside of the shell is covered with insulation material, with the open ends aligned; secondly, the pipeline for LNG to enter the innermost layer also plays a supporting role. A hole is punched at the bottom of the shell to allow the LNG inlet pipeline to pass through, and the shell and the LNG inlet pipeline are welded together; finally, the open end is covered as a whole, and then the open end is sealed by using gaskets, nuts, etc.

[0023] LNG enters the innermost layered shell cavity through the LNG inlet 14 at the bottom middle part of the cold storage device, the LNG inlet valve 1 and the first LNG solution pump 2. With the continuous injection of LNG, when the inner layer LNG submerges the inner and middle layer channel openings 13-1, LNG begins to enter the middle layer cavity. When the middle layer LNG submerges the middle and outer layer channel openings, LNG begins to enter the outermost layer cavity, and finally passes through the second LNG solution pump 3 and the LNG outlet valve 4 to enter the downstream cold system. In the inner, middle and outer three-layer cavities of the cold storage device, the cold storage material 12 will be immersed in LNG. The cold energy is stored, and the outer side of the shell of the inner, middle and outer three layers of the cavity is covered with a layer of insulation material 11 to maintain the temperature; when the cold energy is used, the refrigerant solution pump and the refrigerant control valve are opened respectively, and the refrigerant will pass through the first refrigerant solution pump 5 and the first refrigerant control valve 6, the second refrigerant solution pump 7 and the second refrigerant control valve 8, the third refrigerant solution pump 9 and the third refrigerant control valve 10 in sequence to enter the hollow channel of the cold storage material 12 to exchange heat with the cold storage material 12, and bring the required cold out of the cold storage device and enter the place where cold supply is needed to carry out the next step. Through this cold storage device, the cold energy contained in LNG can be effectively utilized, and a longer period of cold supply can be achieved, which plays a certain role in resource saving.

[0024] The detailed description of the efficient cold storage device for LNG in the above reference embodiment is illustrative rather than restrictive, and several embodiments can be listed according to the limited scope. Therefore, changes and modifications without departing from the overall concept of the present invention should fall within the scope of protection of the present invention.

Claims

1. An efficient cold storage device for LNG, characterized by: It includes a shell, a cold storage material, an LNG inlet valve, an LNG outlet valve, a first LNG solution pump, a second LNG solution pump, a first refrigerant solution pump, a first refrigerant control valve, a second refrigerant solution pump, a second refrigerant control valve, a third refrigerant solution pump, and a third refrigerant control valve. The inner cavity of the shell is provided with a plurality of layered shells interconnected with each other, and the upper part of each layered shell is provided with a channel opening interconnected with each other. The inner cavity formed by the layered shells is provided with cold storage material, and the cold storage material is provided with a coil-type cylindrical hollow channel. Each hollow channel is connected end to end to form a whole interconnected and has only one inlet and one outlet to form a through channel for the flow of refrigerant. Each through channel is respectively connected with a refrigerant solution pump and a refrigerant control valve. The bottom of the innermost layered shell is provided with an LNG inlet. The LNG inlet is connected to the first LNG solution pump and the LNG inlet valve through a pipeline, and the bottom side wall of the shell is provided with an LNG outlet, and the LNG outlet is connected to the second LNG solution pump and the LNG outlet valve through a pipeline; the inner cavity of the shell is set as an inner, middle and outer three-layered shell, and the inner, middle and outer three-layered shell cavities are respectively provided with cold storage materials, and the cold storage materials are provided with a hollow channel, and the inlet pipe section of the hollow channel is respectively connected to the first refrigerant solution pump and the first refrigerant control valve, the second refrigerant solution pump and the second refrigerant control valve, the third refrigerant solution pump and the third refrigerant control valve, and the hollow channel is filled with refrigerant; the height of the channel port is set to be the highest in the innermost layer, and the lower layer from the inside to the outside, and the outer periphery of the shell and the layered shell is coated with a layer of thermal insulation material.

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