CN112179046B - Liquid air energy storage and ammonia synthesis integrated device and method - Google Patents

Abstract

The invention discloses a liquid air energy storage and ammonia synthesis integrated device and a method. In the electricity consumption valley period, redundant electric power drives the air separation liquefaction unit to obtain liquid nitrogen and store the liquid nitrogen in the liquid air storage tank; the source of nitrogen in the ammonia synthesis circulation system can utilize liquid nitrogen in a liquid air storage tank on one hand, and can also utilize gaseous nitrogen separated from an air separation plant on the other hand. During the peak period of electricity consumption, after being pressurized and preheated, liquid nitrogen in the liquid air storage tank can be directly supplied to the ammonia synthesis circulation system as a raw material on one hand, and can enter the air turbine set for expansion power generation after being heated on the other hand, and then is pressurized and supplied to the ammonia synthesis circulation system.

Description

A liquid air energy storage and ammonia synthesis integrated device and method

technical field

The invention relates to a novel integrated device and method for liquid air energy storage and ammonia synthesis, belonging to the technical fields of liquid air energy storage, ammonia synthesis and air separation.

Background technique

Liquid air energy storage technology is a cryogenic energy storage technology that uses liquid air or nitrogen as the energy storage medium. During the low electricity consumption period, the electric energy is used to produce liquid air or nitrogen, and the heat of compression generated during the air or nitrogen compression process is stored at the same time; during the peak electricity consumption period, the liquid air or nitrogen is pressurized by the pressurizing pump, the low temperature cold energy is recovered and further After preheating, the air turbine is driven to generate power. As an emerging large-scale energy storage technology, liquid air energy storage has the characteristics of high energy storage density, short response time, no geographical restrictions and no environmental pollution, and has received extensive attention.

Ammonia, as the carrier of hydrogen, is one of the most potential long-term hydrogen storage media. In addition, ammonia gas can be used to manufacture ammonia water, compound fertilizer, nitric acid, soda ash, etc., and is widely used in chemical, light industry, pharmaceutical, synthetic fiber and other fields. Liquid ammonia can also be used as a green refrigerant in the field of refrigeration and air conditioning. Ammonia is produced commercially by the Haber process by the direct combination of nitrogen and hydrogen at high temperature, high pressure and in the presence of a catalyst. Nitrogen, as one of the important raw materials in the ammonia synthesis process, is generally prepared through an air separation device. The air separation unit needs to run all day to provide the high-purity nitrogen required for ammonia synthesis, which is one of the reasons for the high energy consumption and high cost in the ammonia synthesis process.

To sum up, nitrogen is a common working medium required for liquid air energy storage and ammonia synthesis, so it has a good combination point. It can be considered that during the low electricity consumption period (low electricity price), liquid air energy storage stores liquid nitrogen, and during the peak electricity consumption period (high electricity price), liquid air energy storage releases nitrogen gas to supply ammonia synthesis, so as to avoid consuming high-priced electricity to produce nitrogen and supply ammonia. gas synthesis. Therefore, how to efficiently integrate liquid air energy storage with ammonia synthesis is of great significance for reducing the operation and investment costs of ammonia synthesis and improving the power generation efficiency of liquid air energy storage.

SUMMARY OF THE INVENTION

Purpose of the invention: The technical problem to be solved by the present invention is to provide an integrated device and method for liquid air energy storage and ammonia synthesis, which utilizes liquid air energy storage to store nitrogen during low electricity consumption periods, and Release nitrogen to supply ammonia synthesis during peak electricity consumption, avoid consuming peak electricity to produce nitrogen, reduce the operation and investment cost of ammonia synthesis by using peak and valley electricity prices, improve the efficiency of liquid air energy storage, and make liquid air energy storage and ammonia synthesis independent It is an efficient and reasonable way of integrating liquid air energy storage and ammonia synthesis.

For realizing the above-mentioned purpose of the invention, the technical scheme adopted in the present invention is as follows:

An integrated device for liquid air energy storage and ammonia synthesis, the device comprising: a liquid air energy storage cycle system and an ammonia synthesis cycle system;

The liquid air energy storage cycle system includes: an air separation and liquefaction unit and an air power generation unit; wherein, the air separation and liquefaction unit includes: an air compressor unit, and the air compressor unit has a right input end and a left output end , the lower input end and the lower output end; the first air three-way valve, the left output end of the first air three-way valve is connected with the right input end of the air compressor unit; the first air three-way valve The right input end of the valve is connected to the purified ambient air; the low temperature cooler, the right input end of the low temperature cooler is connected with the left output end of the air compressor unit; the low temperature turboexpander, the low temperature The input end of the turboexpander is connected with the left output end of the cryogenic cooler; the liquid air separator, the upper input end of the liquid air separator is connected with the output end of the cryogenic turboexpander; the second Air three-way valve, the upper input end of the second air three-way valve is connected with the lower output end of the liquid air separator; the third air three-way valve, the upper input end of the third air three-way valve is connected to The lower output end of the second air three-way valve is connected; the liquid air storage tank, the input end of the liquid air storage tank is connected with the right output end of the third air three-way valve; the fourth air three-way valve , the right input end of the fourth air three-way valve is connected to the left output end of the liquid air separator; the fifth air three-way valve, the lower input end of the fifth air three-way valve is connected to the The upper output end of the fourth air three-way valve is connected; the right output end of the fifth air three-way valve is connected with the left upper input end of the low temperature cooler; the sixth air three-way valve, the sixth air The lower input end of the three-way valve is connected to the upper right output end of the cryogenic cooler; the right input end of the sixth air three-way valve is connected to the right input end of the air compressor unit; The left output end of the six-air three-way valve is connected to the environment; a cold storage unit, the cold storage unit has a right port and a left port; a first low-temperature three-way valve, the right side of the first low-temperature three-way valve The port is connected with the left port of the cold storage unit; the first cryogenic circulation pump, the input end of the first cryogenic circulation pump is connected with the upper output end of the first cryogenic three-way valve; the first cryogenic circulation pump The output end of the pump is connected to the lower left input end of the low temperature cooler; the second low temperature three-way valve, the upper input end of the second low temperature three way valve is connected to the lower right output end of the low temperature cooler; The left port of the second low temperature three-way valve is connected with the right port of the cold storage unit; the medium temperature heat storage unit has a right port and a left port; the first medium temperature three-way valve , the right port of the first medium-temperature three-way valve is connected to the left port of the medium-temperature heat storage unit; the first medium-temperature circulating pump, the input end of the first medium-temperature circulating pump is connected to the first medium-temperature three-way The upper output end of the valve is connected; the output end of the first medium temperature circulating pump is connected with the lower input end of the air compressor unit; the second medium temperature three-way valve, the upper input end of the second medium temperature three-way valve is connected to The lower output end of the air compressor unit is connected; the left port of the second intermediate temperature three-way valve is connected to the right port of the intermediate temperature heat storage unit; Rectification tower, the upper right output end of the rectification tower is connected with the left input end of the fifth air three-way valve; the upper right input end of the rectification tower is connected with the second air three-way valve The left output end is connected; the right lower input end of the rectifying tower is connected with the lower output end of the fourth air three-way valve; the right lower output end of the rectifying tower is connected to the third air three-way valve. The left input end of the through valve is connected; the air power generation unit and the air separation and liquefaction unit share a liquid air storage tank, a cold storage unit, a first low temperature three-way valve, a second low temperature three-way valve, a medium temperature heat storage unit, The first medium temperature three-way valve and the second medium temperature three-way valve further include: a low temperature pressurizing pump, the input end of the low temperature pressurizing pump is connected with the output end of the liquid air storage tank; an evaporator, the evaporator The left input end of the evaporator is connected to the output end of the cryogenic pressure pump; the left output end of the evaporator is connected to the lower input end of the first low temperature three-way valve; the first nitrogen three-way valve, the The left input end of the first nitrogen three-way valve is connected with the right output end of the evaporator; the third low-temperature three-way valve, the upper input end of the third low-temperature three-way valve is connected with the second low-temperature three-way valve The lower output end of the valve is connected; the left output end of the third low temperature three-way valve is connected with the right input end of the evaporator; the second low temperature circulating pump, the input end of the second low temperature circulating pump is connected to the The lower output end of the third low temperature three-way valve is connected; the output end of the second low temperature circulating pump is connected to the right input end of the evaporator; the second medium temperature circulating pump, the input of the second medium temperature circulating pump The third medium temperature three-way valve, the upper input end of the third medium temperature three-way valve is connected with the output end of the second medium temperature circulating pump; the The left input end of the third intermediate temperature three-way valve is connected to the right port of the intermediate temperature heat storage unit; for the air turbine unit, the left input end of the air turbine unit is connected to the first nitrogen three-way valve. The right output end is connected; the upper output end of the air turbine unit is connected with the lower input end of the first intermediate temperature three-way valve; the upper input end of the air turbine unit is connected with the third intermediate temperature three-way valve The lower output of the connection;

The ammonia synthesis cycle system includes: an air separation plant, which has a nitrogen output end and an oxygen output end; a second nitrogen three-way valve, the lower input end of the second nitrogen three-way valve and the air The nitrogen output end of the branch factory is connected; the upper output end of the second nitrogen three-way valve is connected with the lower input end of the first air three-way valve; the first mixing chamber, the right side of the first mixing chamber is input The end is connected with the left output end of the second nitrogen three-way valve; the upper input end of the first mixing chamber is connected with the right output end of the air turbine unit; the hydrogen generator, the hydrogen generator The hydrogen output end of the first mixing chamber is connected to the lower input end of the first mixing chamber; the second mixing chamber, the upper input end of the second mixing chamber is connected to the lower output end of the first nitrogen three-way valve; preheater , the right input end of the preheater is connected with the left output end of the second mixing chamber; the normal temperature cooler, the input end of the normal temperature cooler is connected with the right output end of the preheater; A liquid ammonia separator, the upper input end of the liquid ammonia separator is connected with the output end of the normal temperature cooler; a liquid ammonia throttle valve, the input end of the liquid ammonia throttle valve is connected with the output end of the liquid ammonia separator The lower output end is connected; the liquid ammonia storage tank, the input end of the liquid ammonia storage tank is connected with the output end of the liquid ammonia throttle valve; the scavenging unit, the left input end of the scavenging unit is connected to the liquid ammonia The right output end of the ammonia separator is connected; the upper output end of the scavenging unit is connected to the lower input end of the second mixing chamber; the hydrogen separation unit, the left input end of the hydrogen separation unit is connected to the The right output end of the gas unit is connected; the lower output end of the hydrogen separation unit is connected to the external waste gas treatment unit, and the waste gas is discharged into the atmosphere after passing the treatment; the third medium temperature circulating pump, the third medium temperature circulating pump The input end is connected to the lower left output end of the air turbine unit; a high temperature heat storage unit, the high temperature heat storage unit has an upper port and a lower port; a first high temperature three-way valve, the first high temperature three-way valve The upper port of the heat storage unit is connected to the lower port of the high temperature heat storage unit; the first high temperature circulating pump, the input end of the first high temperature circulating pump is connected to the right output end of the first high temperature three-way valve; the second high temperature circulating pump is connected to the right output end of the first high temperature three-way valve; Three-way valve, the lower port of the second high-temperature three-way valve is connected to the upper port of the high-temperature heat storage unit; the upper output end of the second high-temperature three-way valve is connected to the lower right part of the air turbine unit The input end is connected; the second high temperature circulating pump, the output end of the second high temperature circulating pump is connected with the left input end of the first high temperature three-way valve; the input end of the second high temperature circulating pump is connected with the air The lower middle output end of the turbine unit is connected; the mixed gas compressor unit, the right input end of the mixed gas compressor unit is connected with the left output end of the first mixing chamber; the upper output end of the mixed gas compressor unit connected with the lower middle input end of the air turbine unit; the upper input end of the mixed gas compressor unit is connected with the output end of the third medium temperature circulating pump; the left output end of the mixed gas compressor unit is connected to the The right input end of the second mixing chamber is connected; the mixed gas compressor unit The lower input end is connected with the upper output end of the hydrogen separation unit; the ammonia synthesis unit, the upper input end of the ammonia synthesis unit is connected with the left output end of the preheater; the ammonia synthesis unit The lower output end is connected to the left input end of the preheater; the left input end of the ammonia synthesis unit is connected to the output end of the first high temperature circulating pump; the left output end of the ammonia synthesis unit The end is connected to the right input end of the second high temperature three-way valve.

Further, the air compressor unit includes a one-stage or multi-stage air compressor and an air cooler; the air turbine unit includes a one-stage or multi-stage medium temperature heater, a high temperature heater and a turbine and a medium temperature three-way valve ; The mixed gas compressor group includes a one-stage or multi-stage mixed gas compressor and a mixed gas cooler; the ammonia synthesis unit includes a one-stage or multi-stage ammonia gas reactor and an ammonia gas cooler.

Further, the rectifying tower includes: a high pressure chamber, the high pressure chamber has an upper input end, an upper output end, a lower output end, an upper right input end and a lower right input end; the upper right input end of the high pressure chamber connected with the upper right input end of the rectification column; the lower right input end of the high pressure chamber is connected with the lower right input end of the rectification column; packing, the packing is located inside the high pressure chamber; Liquid oxygen throttle valve, the input end of the liquid oxygen throttle valve is connected to the lower output end of the high pressure chamber; low pressure chamber, the low pressure chamber is located on the top of the high pressure chamber; the left side of the low pressure chamber is input The end is connected with the output end of the liquid oxygen throttle valve; the upper output end of the low pressure chamber is connected with the output end on the upper right side of the rectification column; the evaporative condenser is located in the low pressure chamber inside; the input end of the evaporative condenser is connected with the upper output end of the high pressure chamber; the output end of the evaporative condenser is divided into two paths: one is connected to the upper input end of the high pressure chamber, and the other is connected to the The lower right output end of the rectification column is connected.

Further, the cold storage unit, the medium temperature heat storage unit and the high temperature heat storage unit respectively use sensible heat and cold storage materials such as basalt and Solutia VLT; Phase change cold storage materials such as alcohol solution; thermochemical cold storage materials such as silica gel and fluorspar), 20~300℃ (such as Solutia T55, T66 and other sensible heat storage materials; high-density polyethylene, sugar alcohols or nitrates) phase change materials) and latent heat, sensible heat or thermochemical energy storage materials at 20 to 500°C (such as sensible heat storage materials such as cast iron, pebbles and molten salt; phase change materials such as chloride salts and carbonates), can be Single-stage or multi-stage operation in series, and thermal insulation materials are used.

Preferably, the air separation and liquefaction unit can use air or nitrogen as the working medium; the heat transfer fluid of the cold storage unit can be methanol, propane or air, etc.; the heat transfer fluid of the medium temperature heat storage unit can be heat transfer oil or silicone oil, etc.; The heat transfer fluid of the heat unit can be molten salt or the like; the hydrogen generator can be an electrolysis water tank or a hydrogen production device such as fossil fuel hydrogen production.

Further, the present invention also provides an integrated method for using the above-mentioned device for liquid air energy storage and ammonia synthesis. During the low power consumption period, the air separation and liquefaction unit and the ammonia synthesis cycle system work, and the device operates in two modes:

In the first mode, part of the gaseous nitrogen produced by the air separation plant is supplied to the air separation and liquefaction unit to obtain and store liquid nitrogen, and the other part is supplied to the ammonia synthesis cycle system, which specifically includes the following steps:

Air separation and liquefaction unit: A part of the gaseous nitrogen produced by the air separation plant enters the air compressor unit through the second nitrogen three-way valve and the first air three-way valve, and the gaseous nitrogen is compressed to high pressure, and the compression heat generated in the compression process is recovered. It is stored in the medium-temperature heat storage unit; the high-pressure gaseous nitrogen gas at the outlet of the air compressor unit enters the low-temperature cooler, and is cooled to a low temperature by the low-temperature cold energy stored in the cold-storage unit and the gaseous nitrogen gas flowing back, and then enters the low-temperature turboexpander for expansion and pressure reduction. A part of the gaseous nitrogen is liquefied, and the gaseous and liquid nitrogen are separated by the liquid air separator: the liquid nitrogen enters the liquid air storage tank through the second air three-way valve and the third air three-way valve, and the gaseous nitrogen passes through the fourth air three-way valve and the third air three-way valve. The five air three-way valve, the low temperature cooler and the sixth air three-way valve enter the air compressor unit;

Ammonia synthesis cycle system: another part of the gaseous nitrogen produced by the air separation plant enters the first mixing chamber through the second nitrogen three-way valve, is fully mixed with the hydrogen produced by the hydrogen generator, and enters the mixed gas compressor unit to be pressurized to medium pressure, Then it is mixed with the unreacted hydrogen recovered by the hydrogen separation unit and further pressurized to high pressure, and the compression heat generated by the compression process is recovered and stored in the medium temperature heat storage unit; the high pressure gas from the outlet of the mixed gas compressor unit enters the second mixing chamber, and is mixed with The unreacted gas recovered in the scavenging unit is fully mixed, and after being preheated by the preheater, it enters the ammonia synthesis unit to synthesize ammonia, and at the same time, the reaction heat generated during the ammonia synthesis reaction is stored in the high-temperature heat storage unit; after the reaction is completed The mixed gas is cooled to normal temperature through the preheater and the normal temperature cooler in turn, the ammonia gas in the mixed gas is condensed, and then enters the liquid ammonia separator to separate the liquid ammonia and the unreacted gas: the liquid ammonia is throttled and depressurized through the liquid ammonia throttle valve After entering the liquid ammonia storage tank, the unreacted gas passes through the scavenging unit and the hydrogen separation unit in turn to complete the scavenging and hydrogen recovery and finally discharge;

In the second mode, the air separation and liquefaction unit separates and liquefies nitrogen from the air, a part of the liquid nitrogen is stored in the liquid air storage tank, and the other part is supplied to the ammonia synthesis cycle system after being pressurized and preheated, which specifically includes the following steps:

Air separation and liquefaction unit: After the ambient air is purified, it enters the air compressor unit to be pressurized to high pressure through the first air three-way valve, and at the same time, the compression heat generated by the air compression process is recovered and stored in the medium temperature heat storage unit; the high pressure at the outlet of the air compressor unit The air passes through the low temperature cooler, and is cooled to a low temperature by the low temperature cold energy stored in the cold storage unit and the oxygen-enriched air returned to the low temperature, and then enters the low temperature turboexpander for expansion and decompression. Air: Liquid air enters the high pressure chamber of the rectification tower through the second air three-way valve, sprayed from top to bottom, and gaseous air enters the high pressure chamber of the rectification tower through the fourth air three-way valve, and is purged from bottom to top; Gaseous air and liquid air complete heat and mass exchange in the packing, high-purity gaseous nitrogen is gathered at the top of the high-pressure chamber, and oxygen-enriched liquid air is gathered at the bottom of the high-pressure chamber; the oxygen-enriched liquid air at the bottom of the high-pressure chamber is cooled by the liquid oxygen throttle valve Depressurize, enter the low-pressure chamber to release cold energy into gaseous oxygen-enriched air, and then discharge into the environment through the fifth air three-way valve, low temperature cooler and sixth air three-way valve; the high-purity gaseous nitrogen at the top of the high-pressure chamber enters the low-pressure chamber The evaporative condenser is condensed into liquid nitrogen by the throttling and depressurized oxygen-enriched liquid air, part of the liquid nitrogen flows back into the high-pressure chamber for spraying, and the other part of the liquid nitrogen enters the liquid air storage tank through the third air three-way valve; the liquid air A part of the liquid nitrogen in the storage tank is stored, and the other part is pressurized by the low-temperature pressurizing pump and then enters the evaporator to be preheated, and the released cold energy is stored in the cold storage unit; the normal temperature and high pressure gaseous nitrogen at the outlet of the evaporator passes through the first nitrogen three The through valve supplies the ammonia synthesis circulation system;

Ammonia synthesis cycle system: The hydrogen produced by the hydrogen generator enters the mixed gas compressor unit through the first mixing chamber, and after being initially compressed to medium pressure, it is mixed with the unreacted hydrogen recovered in the hydrogen separation unit, and further compressed to high pressure, and the hydrogen is recovered at the same time. The heat of compression generated in the compression process is stored in the medium temperature heat storage unit; the high pressure hydrogen from the outlet of the mixed gas compressor unit enters the second mixing chamber, and is fully mixed with the high pressure nitrogen supplied by the liquid air storage tank and the unreacted gas recovered by the scavenging unit, and then It is preheated by the preheater and enters the ammonia synthesis unit to complete the ammonia synthesis reaction. At the same time, the reaction heat is recovered and stored in the high temperature heat storage unit; the fully reacted mixed gas is cooled to normal temperature through the preheater and the normal temperature cooler in turn, and the mixed gas The ammonia gas in the liquid is condensed, and then enters the liquid ammonia separator to separate the liquid ammonia and the unreacted gas: the liquid ammonia is throttled and depressurized by the liquid ammonia throttle valve and then enters the liquid ammonia storage tank, and the unreacted gas is separated from the hydrogen gas through the scavenging unit in turn. The unit is finally discharged after scavenging and hydrogen recovery.

Further, during the low power consumption period, if the air separation plant is unavailable, the air separation and liquefaction unit can use the rectifying tower to separate and liquefy nitrogen from the air, store a part, and supply the other part to the ammonia synthesis cycle system; if the air separation plant is available , the air separation liquefaction unit can directly liquefy and store the gaseous nitrogen provided by the air separation plant.

Further, the present invention also provides a method for integrating liquid air energy storage and ammonia synthesis using the above-mentioned device. During the peak period of electricity consumption, the air power generation unit and the ammonia synthesis cycle system work, which specifically includes the following steps:

Air power generation unit: The liquid nitrogen stored in the liquid air storage tank is pressurized to a high pressure by a low-temperature pressurized pump, and then enters the evaporator for preheating. Unit; the normal temperature and high pressure gaseous nitrogen at the outlet of the evaporator is divided into two paths through the first nitrogen three-way valve: one part enters the second mixing chamber to supply the ammonia synthesis circulation system, and the other part enters the air turbine unit after two-stage preheating and then expands and generates electricity. Then enter the first mixing chamber to supply the ammonia synthesis circulation system;

Ammonia synthesis cycle system: The hydrogen produced by the hydrogen generator enters the first mixing chamber, is fully mixed with the nitrogen at the outlet of the air turbine unit, and then enters the mixed gas compressor unit to be initially compressed to medium pressure, and then mixed with the unreacted hydrogen recovered from the hydrogen separation unit. After mixing, it is further compressed to high pressure, and at the same time, the compression heat generated by the compression process is recovered and used to preheat the nitrogen in the air turbine unit; the high-pressure gas at the outlet of the mixed gas compressor unit enters the second mixing chamber, and a part of the nitrogen that is split with the evaporator outlet And the unreacted gas recovered in the scavenging unit is fully mixed, and after being preheated by the preheater, it enters the ammonia synthesis unit to synthesize ammonia, and at the same time, the reaction heat generated during the ammonia synthesis reaction is recovered for further preheating in the air turbine unit. After the reaction is completed, the mixed gas is cooled to normal temperature through the preheater and the normal temperature cooler in turn, the ammonia gas in the mixed gas is condensed, and then enters the liquid ammonia separator to separate the liquid ammonia and the unreacted gas: the liquid ammonia passes through the liquid ammonia section. After the flow valve is throttled and depressurized, it enters the liquid ammonia storage tank, and the unreacted gas passes through the scavenging unit and the hydrogen separation unit in turn to complete the scavenging and hydrogen recovery and finally discharge.

Further, during the peak period of electricity consumption, the air turbine unit uses the heat of compression stored in the medium-temperature heat storage unit and the heat of compression generated in real time by the mixed gas compressor unit to preheat nitrogen to a medium temperature, and then use the heat of reaction stored in the high-temperature heat storage unit. The reaction heat generated in real time with the ammonia synthesis unit further preheats the nitrogen to a high temperature, thereby improving the power generation and efficiency of the liquid air energy storage cycle system; when the heat demand of the air turbine unit decreases, the excess air generated by the mixed gas compressor unit in real time The heat of compression can be stored in the medium temperature heat storage unit, and the excess reaction heat generated in real time by the ammonia synthesis unit can be stored in the high temperature heat storage unit.

Further, during the peak period of electricity consumption, the air power generation unit in the liquid air energy storage cycle system provides nitrogen to the ammonia synthesis cycle system in two ways: the first one can pressurize the liquid nitrogen stored in the liquid air storage tank, After preheating and expanding power generation, it is supplied to the ammonia synthesis cycle system without affecting the operation of the liquid air energy storage cycle system; the second can pressurize the liquid nitrogen stored in the liquid air storage tank to the pressure required for the ammonia synthesis reaction, and then Heating and vaporizing is supplied to the ammonia synthesis cycle system to reduce the power consumption of mixed gas compression in the mixed gas compressor group.

Further, the liquid air energy storage cycle system and the ammonia synthesis cycle system can operate independently; during the low electricity consumption period, the liquid air energy storage cycle system is used to store liquid nitrogen, and during the peak electricity consumption period, the nitrogen required for ammonia synthesis is supplied, thereby The nitrogen production process is transferred to the low electricity consumption period, thereby reducing the operation and investment cost of the ammonia synthesis cycle system.

Compared with the prior art, the beneficial effects of the present invention are as follows:

1) The present invention utilizes liquid air energy storage to store nitrogen produced by the air separation plant during the low power consumption period, and releases nitrogen to supply ammonia synthesis during the power consumption peak period, so as to avoid the operation of the air separation plant in the power consumption peak period, thereby Reduce the operating cost of the ammonia synthesis cycle system.

2) The present invention improves the air liquefaction process of liquid air energy storage in combination with the rectifying tower, realizes the direct separation and liquefaction of nitrogen from the air, and does not require additional investment to build an air separation plant, thereby reducing the investment cost of the ammonia synthesis cycle system.

3) In the present invention, by reasonably recovering the heat of compression of medium-temperature gas and the heat of synthesis reaction of high-temperature ammonia gas, the nitrogen gas before expansion in the air turbine unit is heated to a high temperature in two stages, which can significantly increase the power generation capacity of liquid air energy storage and improve the overall efficiency of the system.

4) In the present invention, the liquid air energy storage and the ammonia synthesis can operate independently, and the two do not affect each other, which provides a feasible and effective solution for realizing the efficient integration of the liquid air energy storage and the ammonia synthesis.

Description of drawings

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the above-mentioned and/or other aspects of the present invention will become clearer.

FIG. 1 is a schematic diagram of the overall structure of the integrated device for liquid air energy storage and ammonia synthesis according to the present invention.

FIG. 2 is a schematic diagram of the first embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 1 .

FIG. 2-1 is a schematic diagram of the operation of the first embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 2 during a low power consumption period.

FIG. 2-2 is a schematic diagram of the operation of the first embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 2 during peak hours of electricity consumption.

FIG. 3 is a schematic diagram of a second embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 1 .

FIG. 3-1 is a schematic diagram of the operation of the second embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 3 during a low power consumption period.

FIG. 3-2 is a schematic diagram of the operation of the second embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 3 during peak hours of electricity consumption.

Among them, the air compressor unit 100, the nth stage air compressor 101, the nth stage air cooler 102, the first air three-way valve 201, the low temperature cooler 202, the low temperature turboexpander 203, the liquid air separator 204, The second air three-way valve 205, the third air three-way valve 206, the liquid air storage tank 207, the fourth air three-way valve 208, the fifth air three-way valve 209, the sixth air three-way valve 210, the cold storage unit 211 , the first low-temperature three-way valve 212, the first low-temperature circulating pump 213, the second low-temperature three-way valve 214, the medium-temperature heat storage unit 215, the first medium-temperature three-way valve 216, the first medium-temperature circulating pump 217, the second medium-temperature three-way Valve 218, rectification tower 300, high pressure chamber 301, packing 302, liquid oxygen throttle valve 303, low pressure chamber 304, evaporative condenser 305, low temperature booster pump 401, evaporator 402, first nitrogen three-way valve 403, Three low temperature three-way valve 404, second low temperature circulating pump 405, second medium temperature circulating pump 406, third medium temperature three-way valve 407, air turbine unit 500, nth stage medium temperature heater 501, nth stage high temperature heater 502 , the nth stage turbine 503, the fourth medium temperature three-way valve 504, the fifth medium temperature three-way valve 505, the air separation plant 601, the second nitrogen three-way valve 602, the first mixing chamber 603, the hydrogen generator 604, the second Mixing chamber 605, preheater 606, room temperature cooler 607, liquid ammonia separator 608, liquid ammonia throttle valve 609, liquid ammonia storage tank 610, scavenging unit 611, hydrogen separation unit 612, third medium temperature circulating pump 613, High-temperature heat storage unit 614, first high-temperature three-way valve 615, first high-temperature circulating pump 616, second high-temperature three-way valve 617, second high-temperature circulating pump 618, mixed gas compressor unit 700, n-th stage mixed gas compressor 701 , the nth stage mixed gas cooler 702 , the ammonia gas synthesis unit 800 , the nth stage ammonia gas reactor 801 , and the nth stage ammonia gas cooler 802 .

Detailed ways

The present invention can be better understood from the following examples.

The structures, proportions, sizes, etc. shown in the drawings in the description are only used to cooperate with the contents disclosed in the description, so as to be understood and read by those who are familiar with the technology, and are not used to limit the conditions for the implementation of the present invention. The technical substantive significance, any modification of the structure, the change of the proportional relationship or the adjustment of the size, should still fall within the technical content disclosed by the present invention without affecting the effect that the present invention can produce and the purpose that can be achieved. within the range that can be covered. Meanwhile, terms such as "upper", "lower", "front", "rear" and "middle" quoted in this specification are only for the convenience of description and clarity, and are not used to limit the scope of the present invention. , the change or adjustment of the relative relationship, without substantial change of the technical content, should also be regarded as the scope of the present invention.

As shown in Figure 1, a liquid air energy storage and ammonia synthesis integrated device of the present invention includes a liquid air energy storage circulation system and an ammonia synthesis circulation system:

The liquid air energy storage cycle system includes: air separation liquefaction unit and air power generation unit:

The air separation and liquefaction unit includes: an air compressor unit 100, an n-th stage air compressor 101, an n-th stage air cooler 102, a first air three-way valve 201, a low temperature cooler 202, a low temperature turboexpander 203, Liquid air separator 204, second air three-way valve 205, third air three-way valve 206, liquid air storage tank 207, fourth air three-way valve 208, fifth air three-way valve 209, sixth air three-way valve 210, cold storage unit 211, first low temperature three-way valve 212, first low temperature circulating pump 213, second low temperature three-way valve 214, medium temperature heat storage unit 215, first medium temperature three-way valve 216, first medium temperature circulating pump 217 , the second medium temperature three-way valve 218, rectification tower 300, high pressure chamber 301, packing 302, liquid oxygen throttle valve 303, low pressure chamber 304, evaporative condenser 305;

Specifically, the air compressor unit 100 has a right input end, a left output end, a lower input end and a lower output end; the left output end of the first air three-way valve 201 and the right input end of the air compressor unit 100 connection, the right input end of the first air three-way valve 201 is connected to the purified ambient air; the right input end of the low temperature cooler 202 is connected to the left output end of the air compressor unit 100; The input end is connected to the left output end of the low temperature cooler 202; the upper input end of the liquid air separator 204 is connected to the output end of the cryogenic turboexpander 203; the upper input end of the second air three-way valve 205 is separated from the liquid air The lower output end of the air conditioner 204 is connected; the upper input end of the third air three-way valve 206 is connected with the lower output end of the second air three-way valve 205; the input end of the liquid air storage tank 207 is connected with the third air three-way valve 206 The right output end is connected; the right input end of the fourth air three-way valve 208 is connected with the left output end of the liquid air separator 204 ; the lower input end of the fifth air three-way valve 209 is connected with the fourth air three-way valve 208 The upper output end of the third air three-way valve 209 is connected to the upper left input end of the low temperature cooler 202; the lower input end of the sixth air three way valve 210 is connected to the upper right side of the low temperature cooler 202. The side output end is connected, the right input end of the sixth air three-way valve 210 is connected with the right input end of the air compressor unit 100, and the left output end of the sixth air three-way valve 210 is connected with the environment; the cold storage unit 211 It has a right port and a left port; the right port of the first cryogenic three-way valve 212 is connected to the left port of the cold storage unit 211 ; the input end of the first cryogenic circulation pump 213 is connected to the upper part of the first cryogenic three-way valve 212 The output end is connected, the output end of the first cryogenic circulation pump 213 is connected with the lower left input end of the cryogenic cooler 202; the upper input end of the second cryogenic three-way valve 214 is connected with the lower right output end of the cryogenic cooler 202, the third The left port of the second low temperature three-way valve 214 is connected to the right port of the cold storage unit 211; the medium temperature heat storage unit 215 has a right port and a left port; the right port of the first medium temperature three-way valve 216 is connected to the medium temperature heat storage unit 216. The left port of the unit 215 is connected; the input end of the first medium temperature circulating pump 217 is connected with the upper output end of the first medium temperature three-way valve 216, and the output end of the first medium temperature circulating pump 217 is connected with the lower input end of the air compressor unit 100 connection; the upper input end of the second intermediate temperature three-way valve 218 is connected to the lower output end of the air compressor unit 100, and the left port of the second intermediate temperature three-way valve 218 is connected to the right port of the intermediate temperature heat storage unit 215; rectification The upper right output end of the tower 300 is connected to the left input end of the fifth air three-way valve 209, the upper right input end of the rectifying tower 300 is connected to the left output end of the second air three-way valve 205, and the rectifying tower 300 The lower right input end of the rectifying tower 300 is connected to the lower output end of the fourth air three-way valve 208, and the lower right output end of the rectifying tower 300 is connected to the left input end of the third air three-way valve 206;

The air power generation unit and the air separation and liquefaction unit share the liquid air storage tank 207, the cold storage unit 211, the first low temperature three-way valve 212, the second low temperature three-way valve 214, the medium temperature heat storage unit 215, the first medium temperature three-way valve 216 and The second medium-temperature three-way valve 218 further includes: a low-temperature booster pump 401, an evaporator 402, a first nitrogen three-way valve 403, a third low-temperature three-way valve 404, a second low-temperature circulating pump 405, and a second medium-temperature circulating pump 406 , the third medium temperature three-way valve 407, the air turbine unit 500, the nth stage medium temperature heater 501, the nth stage high temperature heater 502, the nth stage turbine 503, the fourth medium temperature three-way valve 504, the fifth medium temperature three-way valve Through valve 505;

Specifically, the input end of the cryogenic pressure pump 401 is connected to the output end of the liquid air storage tank 207; the left input end of the evaporator 402 is connected to the output end of the cryogenic pressure pump 401, and the left output end of the evaporator 402 is connected to the output end of the cryogenic pressure pump 401. The lower input end of the first low temperature three-way valve 212 is connected; the left input end of the first nitrogen three-way valve 403 is connected with the right output end of the evaporator 402; the upper input end of the third low temperature three-way valve 404 is connected to the second The lower output end of the low-temperature three-way valve 214 is connected, the left output end of the third low-temperature three-way valve 404 is connected with the right input end of the evaporator 402; the input end of the second low-temperature circulating pump 405 is connected to the third low-temperature three-way valve The lower output end of 404 is connected, the output end of the second low temperature circulating pump 405 is connected with the right input end of the evaporator 402; the input end of the second medium temperature circulating pump 406 is connected with the lower output end of the second medium temperature three-way valve 218; The upper input end of the third medium-temperature three-way valve 407 is connected to the output end of the second medium-temperature circulating pump 406, and the left input end of the third medium-temperature three-way valve 407 is connected to the right port of the medium-temperature heat storage unit 215; the air turbine The left input end of the unit 500 is connected to the right output end of the first nitrogen three-way valve 403, the upper output end of the air turbine unit 500 is connected to the lower input end of the first medium temperature three-way valve 216, and the air turbine unit 500 The upper input end of is connected with the lower output end of the third medium temperature three-way valve 407;

The ammonia synthesis cycle system includes: air separation plant 601, second nitrogen three-way valve 602, first mixing chamber 603, hydrogen generator 604, second mixing chamber 605, preheater 606, room temperature cooler 607, liquid ammonia separation 608, liquid ammonia throttle valve 609, liquid ammonia storage tank 610, scavenging unit 611, hydrogen separation unit 612, third medium temperature circulating pump 613, high temperature heat storage unit 614, first high temperature three-way valve 615, first high temperature Circulation pump 616, second high temperature three-way valve 617, second high temperature circulation pump 618, mixed gas compressor group 700, n-th mixed gas compressor 701, n-th mixed gas cooler 702, ammonia synthesis unit 800, n-stage ammonia gas reactor 801, n-th stage ammonia gas cooler 802;

Specifically, the air separation plant 601 has a nitrogen output end and an oxygen output end; the lower input end of the second nitrogen three-way valve 602 is connected to the nitrogen output end of the air separation plant 601, and the upper output end of the second nitrogen three-way valve 602 is connected to The lower input end of the first air three-way valve 201 is connected; the right input end of the first mixing chamber 603 is connected with the left output end of the second nitrogen three-way valve 602, and the upper input end of the first mixing chamber 603 is connected to the air permeability. The right output end of the leveling unit 500 is connected; the hydrogen output end of the hydrogen generator 604 is connected to the lower input end of the first mixing chamber 603; the upper input end of the second mixing chamber 605 is connected to the lower output end of the first nitrogen three-way valve 403 The right input end of the preheater 606 is connected to the left output end of the second mixing chamber 605; the input end of the normal temperature cooler 607 is connected to the right output end of the preheater 606; The upper input end is connected with the output end of the normal temperature cooler 607; the input end of the liquid ammonia throttle valve 609 is connected with the lower output end of the liquid ammonia separator 608; the input end of the liquid ammonia storage tank 610 is connected with the liquid ammonia throttle valve 609. The output end is connected; the left input end of the scavenging unit 611 is connected with the right output end of the liquid ammonia separator 608, and the upper output end of the scavenging unit 611 is connected with the lower input end of the second mixing chamber 605; the hydrogen separation unit 612 The left input end is connected to the right output end of the scavenging unit 611, the lower output end of the hydrogen separation unit 612 is connected to the external environment; the input end of the third medium temperature circulating pump 613 is connected to the lower left output end of the air turbine unit 500 The high temperature heat storage unit 614 has an upper port and a lower port; the upper port of the first high temperature three-way valve 615 is connected with the lower port of the high temperature heat storage unit 614; the input end of the first high temperature circulating pump 616 is connected to the first high temperature three-way valve The right output end of the through valve 615 is connected; the lower port of the second high temperature three-way valve 617 is connected to the upper port of the high temperature heat storage unit 614, and the upper output end of the second high temperature three-way valve 617 is connected to the lower part of the air turbine unit 500. The right input end is connected; the output end of the second high temperature circulating pump 618 is connected to the left input end of the first high temperature three-way valve 615 , and the input end of the second high temperature circulating pump 618 is connected to the lower middle output end of the air turbine unit 500 Connection; the right input end of the mixed gas compressor unit 700 is connected to the left output end of the first mixing chamber 603, the upper output end of the mixed gas compressor unit 700 is connected to the lower middle input end of the air turbine unit 500, and the mixed gas compresses The upper input end of the unit 700 is connected to the output end of the third medium temperature circulating pump 613, the left output end of the mixed gas compressor unit 700 is connected to the right input end of the second mixing chamber 605, and the lower input end of the mixed gas compressor unit 700 It is connected to the upper output end of the hydrogen separation unit 612; the upper input end of the ammonia synthesis unit 800 is connected to the left output end of the preheater 606, and the lower output end of the ammonia synthesis unit 800 is connected to the left input end of the preheater 606 End connection, left input of ammonia synthesis unit 800 The terminal is connected to the output terminal of the first high temperature circulating pump 616 , and the left output terminal of the ammonia synthesis unit 800 is connected to the right input terminal of the second high temperature three-way valve 617 .

Using the above-mentioned device to carry out the method for liquid air energy storage and ammonia synthesis, comprising the following steps:

During the low electricity consumption period, the air separation and liquefaction unit and the ammonia gas synthesis cycle system work, and the operation of the device is divided into two modes:

In the first mode, part of the gaseous nitrogen produced by the air separation plant 601 is supplied to the air separation and liquefaction unit to obtain and store liquid nitrogen, and the other part is supplied to the ammonia synthesis cycle system, which specifically includes the following steps: the air separation and liquefaction unit works: the air separation plant 601 A part of the gaseous nitrogen produced enters the air compressor unit 100 through the second nitrogen three-way valve 602 and the first air three-way valve 201, the gaseous nitrogen is compressed to high pressure, and the compression heat generated during the compression process is recovered and stored in the medium temperature heat storage. Unit 215; the high-pressure gaseous nitrogen gas at the outlet of the air compressor unit 100 enters the low-temperature cooler 202, is cooled to a low temperature by the low-temperature cold energy stored in the cold storage unit 211 and the backflow gaseous nitrogen gas, and then enters the low-temperature turboexpander 203 for expansion and pressure reduction, A part of the gaseous nitrogen is liquefied, and the gaseous and liquid nitrogen are separated by the liquid air separator 204: the liquid nitrogen enters the liquid air storage tank 207 through the second air three-way valve 205 and the third air three-way valve 206, and the gaseous nitrogen passes through the fourth air three-way valve 207. The through valve 208, the fifth air three-way valve 209, the low temperature cooler 202 and the sixth air three-way valve 210 enter the air compressor unit 100; the ammonia synthesis cycle system works: another part of the gaseous nitrogen produced by the air separation plant 601 passes through The second nitrogen three-way valve 602 enters the first mixing chamber 603, is fully mixed with the hydrogen produced by the hydrogen generator 604, enters the mixed gas compressor unit 700 to be pressurized to a medium pressure, and is then mixed with the unreacted hydrogen recovered by the hydrogen separation unit 612 and further pressurized to high pressure, and at the same time, the compression heat generated by the compression process is recovered and stored in the medium temperature heat storage unit 215; The gas is fully mixed, and after being preheated by the preheater 606, it enters the ammonia synthesis unit 800 to synthesize ammonia, and at the same time, the reaction heat generated during the ammonia synthesis reaction is stored in the high temperature heat storage unit 614; the mixed gas after the reaction is completed in turn passes through The preheater 606 and the normal temperature cooler 607 are cooled to normal temperature, the ammonia gas in the mixed gas is condensed, and then enters the liquid ammonia separator 608 to separate the liquid ammonia and the unreacted gas: after the liquid ammonia is throttled and depressurized through the liquid ammonia throttle valve 609 Entering the liquid ammonia storage tank 610, the unreacted gas passes through the scavenging unit 611 and the hydrogen separation unit 612 in turn to complete scavenging and hydrogen recovery and finally discharge;

In the second mode, the air separation and liquefaction unit separates and liquefies nitrogen from the air, a part of the liquid nitrogen is stored in the liquid air storage tank 207, and the other part is supplied to the ammonia synthesis cycle system after being pressurized and preheated, which specifically includes the following steps: The air separation and liquefaction unit works: after the ambient air is purified, it enters the air compressor unit 100 through the first air three-way valve 201 to be pressurized to a high pressure, and at the same time, the compression heat generated by the air compression process is recovered and stored in the medium temperature heat storage unit 215; the air compressor The high-pressure air at the outlet of the group 100 passes through the low-temperature cooler 202, is cooled to a low temperature by the low-temperature cold energy stored in the cold storage unit 211 and the returned oxygen-enriched air, and enters the low-temperature turboexpander 203 for expansion and pressure reduction. The liquid air separator 204 separates gaseous and liquid air: the liquid air enters the high pressure chamber 301 of the rectification tower 300 through the second air three-way valve 205, and is sprayed from top to bottom, and the gaseous air enters the refined air through the fourth air three-way valve 208. The high-pressure chamber 301 of the distillation column 300 is purged from bottom to top; gaseous air and liquid air complete heat and mass exchange in the packing 302, high-purity gaseous nitrogen is gathered at the top of the high-pressure chamber 301, and oxygen-enriched liquid air is gathered in the high-pressure chamber 301 The oxygen-enriched liquid air at the bottom of the high-pressure chamber 301 passes through the liquid oxygen throttle valve 303 to cool down and depressurize, and enters the low-pressure chamber 304 to release cold energy into gaseous oxygen-enriched air, and then passes through the fifth air three-way valve 209, the cryogenic cooler 202 and the sixth air three-way valve 210 are discharged into the environment; the high-purity gaseous nitrogen at the top of the high-pressure chamber 301 enters the evaporative condenser 305 of the low-pressure chamber 304, and is condensed into liquid nitrogen by the throttling and depressurized oxygen-rich liquid air, and a part of the liquid The nitrogen flows back into the high pressure chamber 301 for spraying, and the other part of the liquid nitrogen enters the liquid air storage tank 207 through the third air three-way valve 206; a part of the liquid nitrogen in the liquid air storage tank 207 is stored, and the other part is pressurized by the cryogenic pressure pump 401 After entering the evaporator 402 to preheat, the released cold energy is stored in the cold storage unit 211; the normal temperature and high pressure gaseous nitrogen at the outlet of the evaporator 402 is supplied to the ammonia synthesis circulation system through the first nitrogen three-way valve 403; the ammonia synthesis circulation system Work: The hydrogen produced by the hydrogen generator 604 enters the mixed gas compressor unit 700 through the first mixing chamber 603, and after being preliminarily compressed to a medium pressure, it is mixed with the unreacted hydrogen recovered in the hydrogen separation unit 612, and further compressed to a high pressure, and the hydrogen is recovered at the same time. The heat of compression generated during the compression process is stored in the medium temperature heat storage unit 215; the high pressure hydrogen gas at the outlet of the mixed gas compressor unit 700 enters the second mixing chamber 605, and is combined with the high pressure nitrogen supplied by the liquid air storage tank 207 and the unreacted unreacted gas recovered by the scavenging unit 611. The gas is fully mixed, and then preheated by the preheater 606 into the ammonia synthesis unit 800 to complete the ammonia synthesis reaction, while the reaction heat is recovered and stored in the high temperature heat storage unit 614; the fully reacted mixed gas passes through the preheater 606 and The normal temperature cooler 607 is cooled to normal temperature, and the ammonia gas in the mixed gas is condensed, and then enters the liquid ammonia separator 6 08 Separation of liquid ammonia and unreacted gas: The liquid ammonia enters the liquid ammonia storage tank 610 after being throttled and depressurized through the liquid ammonia throttle valve 609, and the unreacted gas passes through the scavenging unit 611 and the hydrogen separation unit 612 in turn to complete scavenging and hydrogen recovery after the final discharge.

During peak hours of electricity consumption, the air power generation unit and the ammonia synthesis cycle system work, which includes the following steps:

Working of the air power generation unit: the liquid nitrogen stored in the liquid air storage tank 207 is pressurized to a high pressure by the low-temperature pressurizing pump 401, and then enters the evaporator 402 for preheating, and the liquid nitrogen is evaporated into gaseous nitrogen, and the cold energy released by the evaporation of the liquid nitrogen is simultaneously Stored in the cold storage unit 211; the normal temperature and high pressure gaseous nitrogen at the outlet of the evaporator 402 is divided into two paths through the first nitrogen three-way valve 403: one part enters the second mixing chamber 605 to supply the ammonia synthesis circulation system, and the other part enters the air turbine unit 500 After two-stage preheating, it expands and generates electricity, and then enters the first mixing chamber 603 to supply the ammonia synthesis circulation system; the ammonia synthesis circulation system works: the hydrogen produced by the hydrogen generator 604 enters the first mixing chamber 603, and is connected with the air turbine unit 500. The nitrogen at the outlet is fully mixed, and then enters the mixed gas compressor unit 700 to be preliminarily compressed to a medium pressure, mixed with the unreacted hydrogen recovered by the hydrogen separation unit 612 and further compressed to a high pressure, while the compression heat generated by the compression process is recovered for preliminary preheating of the air. The nitrogen in the turbine unit 500; the high-pressure gas at the outlet of the mixed gas compressor unit 700 enters the second mixing chamber 605, and is fully mixed with a part of the nitrogen branched from the outlet of the evaporator 402 and the unreacted gas recovered in the scavenging unit 611, and is preheated. After preheating, the device 606 enters the ammonia synthesis unit 800 to synthesize ammonia, and at the same time, the reaction heat generated in the ammonia synthesis reaction process is recovered for further preheating the nitrogen in the air turbine unit 500; the mixed gas after the reaction is completed in turn by preheating Cooler 606 and room temperature cooler 607 are cooled to room temperature, the ammonia gas in the mixed gas is condensed, and then enters the liquid ammonia separator 608 to separate the liquid ammonia and the unreacted gas: the liquid ammonia enters the liquid ammonia through the liquid ammonia throttle valve 609 after being throttled and depressurized. In the ammonia storage tank 610, the unreacted gas passes through the scavenging unit 611 and the hydrogen separation unit 612 in turn to complete scavenging and hydrogen recovery and finally discharge.

During peak hours of electricity consumption, the air turbine unit 500 uses the heat of compression stored in the medium-temperature heat storage unit 215 and the heat of compression generated in real time by the mixed gas compressor unit 700 to preheat nitrogen to an intermediate temperature, and then utilizes the heat of reaction stored in the high-temperature heat storage unit 614. The reaction heat generated in real time with the ammonia synthesis unit 800 further preheats the nitrogen gas to a high temperature, thereby improving the power generation and efficiency of the liquid air energy storage cycle system; when the heat demand of the air turbine unit 500 decreases, the mixed gas compressor unit 700 real-time The excess heat of compression generated may be stored in the medium temperature heat storage unit 215 , and the excess reaction heat generated in real time by the ammonia synthesis unit 800 may be stored in the high temperature heat storage unit 614 .

FIG. 2 is a first embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 1 . This embodiment is applicable to the case where the air separation plant 601 has been constructed, and the liquid air energy storage cycle system only provides the liquefaction function (without the rectification tower 300), which can reduce the operating cost of the ammonia synthesis cycle system; the ammonia synthesis cycle system is in Nitrogen is supplied through the air separation plant 601 during the low electricity consumption period, and nitrogen is supplied through the liquid air energy storage circulation system during the electricity consumption peak period.

Specifically, the liquid air energy storage cycle system includes: an air separation and liquefaction unit and an air power generation unit. The air separation and liquefaction unit includes: air compressor unit 100, n-th stage air compressor 101, n-th stage air cooler 102, first air three-way valve 201, low temperature cooler 202, low temperature turboexpander 203, liquid air Separator 204, second air three-way valve 205, third air three-way valve 206, liquid air storage tank 207, fourth air three-way valve 208, fifth air three-way valve 209, sixth air three-way valve 210, Cold storage unit 211, first low temperature three-way valve 212, first low temperature circulating pump 213, second low temperature three-way valve 214, medium temperature heat storage unit 215, first medium temperature three-way valve 216, first medium temperature circulating pump 217, Two medium temperature three-way valve 218; the air power generation unit and the air separation and liquefaction unit share the liquid air storage tank 207, the cold storage unit 211, the first low temperature three-way valve 212, the second low temperature three-way valve 214, the medium temperature heat storage unit 215, the first low temperature three-way valve 214. A medium-temperature three-way valve 216 and a second medium-temperature three-way valve 218, further comprising: a cryogenic pressure pump 401, an evaporator 402, a first nitrogen three-way valve 403, a third low-temperature three-way valve 404, and a second cryogenic circulation pump 405 , the second medium temperature circulating pump 406, the third medium temperature three-way valve 407, the air turbine unit 500, the nth stage medium temperature heater 501, the nth stage high temperature heater 502, the nth stage turbine 503, the fourth medium temperature tee Valve 504, the fifth medium temperature three-way valve 505; the ammonia synthesis cycle system includes: air separation plant 601, second nitrogen three-way valve 602, first mixing chamber 603, hydrogen generator 604, second mixing chamber 605, preheating 606, room temperature cooler 607, liquid ammonia separator 608, liquid ammonia throttle valve 609, liquid ammonia storage tank 610, scavenging unit 611, hydrogen separation unit 612, third medium temperature circulating pump 613, high temperature heat storage unit 614, The first high temperature three-way valve 615, the first high temperature circulating pump 616, the second high temperature three-way valve 617, the second high temperature circulating pump 618, the mixed gas compressor group 700, the nth stage mixed gas compressor 701, the nth stage mixed gas cooler 702, ammonia synthesis unit 800, nth stage ammonia gas reactor 801, nth stage ammonia gas cooler 802;

During the low electricity consumption period, the air separation and liquefaction unit and the ammonia synthesis cycle system work, as shown in Figure 2-1:

A part of the gaseous nitrogen produced by the air separation plant 601 is supplied to the air separation and liquefaction unit to obtain and store liquid nitrogen, and the other part is supplied to the ammonia synthesis cycle system, which specifically includes the following steps: the air separation and liquefaction unit works: a part of the gaseous nitrogen produced by the air separation plant 601, Entering the air compressor unit 100 through the second nitrogen three-way valve 602 and the first air three-way valve 201, the gaseous nitrogen is compressed to a high pressure (about 120bar), and the heat of compression (about 220°C) generated during the compression process is recovered and stored in the The medium temperature heat storage unit 215; the high pressure gaseous nitrogen gas from the outlet of the air compressor unit 100 enters the low temperature cooler 202, is cooled to a low temperature by the low temperature cold energy stored in the cold storage unit 211 and the gaseous nitrogen gas returned, and then enters the low temperature turboexpander 203 for expansion Depressurization (1bar), in which a part of the gaseous nitrogen is liquefied, and the gaseous and liquid nitrogen are separated by the liquid air separator 204: the liquid nitrogen enters the liquid air storage tank 207 through the second air three-way valve 205 and the third air three-way valve 206, and the gaseous state Nitrogen enters the air compressor unit 100 through the fourth air three-way valve 208, the fifth air three-way valve 209, the low temperature cooler 202 and the sixth air three-way valve 210; the ammonia synthesis cycle system works: produced by the air separation plant 601 Another part of gaseous nitrogen enters the first mixing chamber 603 through the second nitrogen three-way valve 602, is fully mixed with the hydrogen produced by the hydrogen generator 604, enters the mixed gas compressor unit 700 and is pressurized to a medium pressure (about 28 bar), and then mixes with the hydrogen gas. The unreacted hydrogen recovered by the separation unit 612 is mixed and further pressurized to a high pressure (about 150 bar), while the heat of compression (about 230° C.) generated during the compression process is recovered and stored in the medium temperature heat storage unit 215; The high-pressure gas enters the second mixing chamber 605, is fully mixed with the unreacted gas recovered in the scavenging unit 611, and is preheated by the preheater 606 into the ammonia synthesis unit 800 to synthesize ammonia. The reaction heat (about 500 ° C) is stored in the high temperature heat storage unit 614; the mixed gas after the reaction is completed is cooled to normal temperature through the preheater 606 and the normal temperature cooler 607 in turn, the ammonia in the mixed gas is condensed, and then enters the liquid ammonia separation The device 608 separates the liquid ammonia and the unreacted gas: the liquid ammonia enters the liquid ammonia storage tank 610 after being throttled and depressurized through the liquid ammonia throttle valve 609, and the unreacted gas passes through the scavenging unit 611 and the hydrogen separation unit 612 to complete the scavenging and hydrogen Final discharge after recycling;

During peak hours of electricity consumption, the air power generation unit and the ammonia synthesis cycle system work, as shown in Figure 2-2:

The air power generation unit works: the liquid nitrogen stored in the liquid air storage tank 207 is pressurized to a high pressure (about 150 bar) by the low-temperature pressurizing pump 401, and then enters the evaporator 402 for preheating, and the liquid nitrogen is evaporated into gaseous nitrogen, and the liquid nitrogen is evaporated at the same time. The released cold energy is stored in the cold storage unit 211; the normal temperature and high pressure gaseous nitrogen at the outlet of the evaporator 402 is divided into two paths through the first nitrogen three-way valve 403: one part enters the second mixing chamber 605 to supply the ammonia synthesis circulation system, and the other part enters the air The turbine unit 500 expands and generates electricity after two-stage preheating, and then enters the first mixing chamber 603 to supply the ammonia synthesis circulation system; the ammonia synthesis circulation system works: the hydrogen produced by the hydrogen generator 604 enters the first mixing chamber 603, and is mixed with the air. The nitrogen at the outlet of the turbine unit 500 is fully mixed, and then enters the mixed gas compressor unit 700 to be initially compressed to a medium pressure (about 28 bar), mixed with the unreacted hydrogen recovered by the hydrogen separation unit 612, and further compressed to a high pressure (about 150 bar), while recycling The heat of compression (about 230°C) generated during the compression process is used to preliminarily preheat the nitrogen in the air turbine unit 500; the high-pressure gas at the outlet of the mixed gas compressor unit 700 enters the second mixing chamber 605, and a part of the nitrogen that is split with the outlet of the evaporator 402 And the unreacted gas recovered in the scavenging unit 611 is fully mixed, and after being preheated by the preheater 606, it enters the ammonia synthesis unit 800 to synthesize ammonia, and the reaction heat (about 500 ° C) generated during the ammonia synthesis reaction is recovered for The nitrogen gas in the air turbine unit 500 is further preheated; the mixed gas after the reaction is completed is cooled to normal temperature by the preheater 606 and the normal temperature cooler 607 in turn, and the ammonia gas in the mixed gas is condensed, and then enters the liquid ammonia separator 608 to separate the liquid Ammonia and unreacted gas: The liquid ammonia enters the liquid ammonia storage tank 610 after being throttled and depressurized through the liquid ammonia throttle valve 609, and the unreacted gas passes through the scavenging unit 611 and the hydrogen separation unit 612 in turn to complete the scavenging and hydrogen recovery and finally discharge .

To further illustrate the operational performance of the first embodiment (FIG. 2), a thermodynamic and economical analysis of the entire system was performed. According to the industrial electricity price in Jiangsu Province (as shown in Table 1, the flat period and the trough period are the trough periods of electricity consumption), the power generation efficiency of the liquid air energy storage cycle system is increased by about 30% (absolute value), as shown in Table 2. It is shown that the corresponding ammonia synthesis cycle system can save about 100 yuan in operating cost per ton of ammonia produced during the peak electricity consumption period.

Table 1 Electricity Price for Industrial Electricity in Jiangsu Province

Table 2 Performance of the liquid air energy storage cycle system in the first embodiment

FIG. 3 is a second embodiment of the integrated device for liquid air energy storage and ammonia synthesis shown in FIG. 1 . This embodiment is suitable for the situation that the air separation plant 601 has not been constructed (or unavailable). By combining with the rectification tower 300, the liquid air energy storage cycle system can provide air separation and liquefaction functions, which can reduce the operation and cost of the ammonia synthesis cycle system. Investment cost; the ammonia synthesis cycle system supplies nitrogen and stores liquid nitrogen through the liquid air energy storage cycle system during the low electricity consumption period, and supplies the ammonia synthesis cycle system through the liquid nitrogen stored in the liquid air energy storage cycle system during the peak electricity consumption period. The specific operation steps are as follows:

During the low electricity consumption period, the air separation and liquefaction unit and the ammonia gas synthesis circulation system work, as shown in Figure 3-1:

The air separation and liquefaction unit works: after the ambient air is purified, it enters the air compressor unit 100 through the first air three-way valve 201 to be pressurized to a high pressure, and at the same time, the compression heat generated by the air compression process is recovered and stored in the medium temperature heat storage unit 215; the air compressor The high-pressure air at the outlet of the group 100 passes through the low-temperature cooler 202, is cooled to a low temperature by the low-temperature cold energy stored in the cold storage unit 211 and the returned oxygen-enriched air, and enters the low-temperature turboexpander 203 for expansion and pressure reduction. The liquid air separator 204 separates gaseous and liquid air: the liquid air enters the high pressure chamber 301 of the rectification tower 300 through the second air three-way valve 205, and is sprayed from top to bottom, and the gaseous air enters the refined air through the fourth air three-way valve 208. The high-pressure chamber 301 of the distillation column 300 is purged from bottom to top; gaseous air and liquid air complete heat and mass exchange in the packing 302, high-purity gaseous nitrogen is gathered at the top of the high-pressure chamber 301, and oxygen-enriched liquid air is gathered in the high-pressure chamber 301 The oxygen-enriched liquid air at the bottom of the high-pressure chamber 301 passes through the liquid oxygen throttle valve 303 to cool down and depressurize, and enters the low-pressure chamber 304 to release cold energy into gaseous oxygen-enriched air, and then passes through the fifth air three-way valve 209, the cryogenic cooler 202 and the sixth air three-way valve 210 are discharged into the environment; the high-purity gaseous nitrogen at the top of the high-pressure chamber 301 enters the evaporative condenser 305 of the low-pressure chamber 304, and is condensed into liquid nitrogen by the throttling and depressurized oxygen-rich liquid air, and a part of the liquid The nitrogen flows back into the high pressure chamber 301 for spraying, and the other part of the liquid nitrogen enters the liquid air storage tank 207 through the third air three-way valve 206; a part of the liquid nitrogen in the liquid air storage tank 207 is stored, and the other part is pressurized by the cryogenic pressure pump 401 After entering the evaporator 402 to preheat, the released cold energy is stored in the cold storage unit 211; the normal temperature and high pressure gaseous nitrogen at the outlet of the evaporator 402 is supplied to the ammonia synthesis circulation system through the first nitrogen three-way valve 403; the ammonia synthesis circulation system Work: The hydrogen produced by the hydrogen generator 604 enters the mixed gas compressor unit 700 through the first mixing chamber 603, and after being preliminarily compressed to a medium pressure, it is mixed with the unreacted hydrogen recovered in the hydrogen separation unit 612, and further compressed to a high pressure, and the hydrogen is recovered at the same time. The heat of compression generated during the compression process is stored in the medium temperature heat storage unit 215; the high pressure hydrogen gas at the outlet of the mixed gas compressor unit 700 enters the second mixing chamber 605, and is combined with the high pressure nitrogen supplied by the liquid air storage tank 207 and the unreacted unreacted gas recovered by the scavenging unit 611. The gas is fully mixed, and then preheated by the preheater 606 into the ammonia synthesis unit 800 to complete the ammonia synthesis reaction, while the reaction heat is recovered and stored in the high temperature heat storage unit 614; the fully reacted mixed gas passes through the preheater 606 and The normal temperature cooler 607 is cooled to normal temperature, the ammonia gas in the mixed gas is condensed, and then enters the liquid ammonia separator 608 to separate the liquid ammonia and the unreacted gas: the liquid ammonia enters the liquid ammonia storage tank after being throttled and depressurized by the liquid ammonia throttle valve 609 610, the unreacted gas passes through the scavenging unit 611 and the hydrogen separation unit 612 in turn to complete the scavenging and hydrogen recovery and finally discharge put.

During the peak period of electricity consumption, the air power generation unit and the ammonia synthesis cycle system work, as shown in Figure 3-2, and the specific steps are the same as those of the first embodiment (Figure 2-2).

The present invention provides an idea and method for an integrated device and method for liquid air energy storage and ammonia synthesis. There are many specific methods and approaches for realizing the technical solution. The above are only the preferred embodiments of the present invention. It should be pointed out that for For those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can also be made, and these improvements and modifications should also be regarded as the protection scope of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims (10)

1. The utility model provides a liquid air energy storage and ammonia synthesis integrated device, its characterized in that, the device includes liquid air energy storage circulating system and ammonia synthesis circulating system, wherein:

the liquid air energy storage circulation system comprises: an air separation liquefaction unit and an air power generation unit;

the air separation liquefaction unit comprises:

an air compressor package (100), the air compressor package (100) having a right side input, a left side output, a lower input, and a lower output;

the left output end of the first air three-way valve (201) is connected with the right input end of the air compressor unit (100); the right input end of the first air three-way valve (201) is connected with the purified ambient air;

the right input end of the low-temperature cooler (202) is connected with the left output end of the air compressor unit (100);

a low temperature turboexpander (203), an input of the low temperature turboexpander (203) being connected to a left side output of the cryocooler (202);

a liquid air separator (204), wherein the upper input end of the liquid air separator (204) is connected with the output end of the low-temperature turbo-expander (203);

a second three-way air valve (205), wherein the upper input end of the second three-way air valve (205) is connected with the lower output end of the liquid air separator (204);

a third air three-way valve (206), wherein the upper input end of the third air three-way valve (206) is connected with the lower output end of the second air three-way valve (205);

the input end of the liquid air storage tank (207) is connected with the right output end of the third air three-way valve (206);

a fourth air three-way valve (208), wherein the right input end of the fourth air three-way valve (208) is connected with the left output end of the liquid air separator (204);

a fifth air three-way valve (209), wherein the lower input end of the fifth air three-way valve (209) is connected with the upper output end of the fourth air three-way valve (208); the right output end of the fifth air three-way valve (209) is connected with the left upper input end of the cryocooler (202);

a sixth air three-way valve (210), wherein the lower input end of the sixth air three-way valve (210) is connected with the upper right output end of the cryocooler (202); the right input end of the sixth air three-way valve (210) is connected with the right input end of the air compressor unit (100); the left output end of the sixth air three-way valve (210) is connected with the environment;

a cold storage unit (211), the cold storage unit (211) having a right side port and a left side port;

a first low temperature three-way valve (212), a right port of the first low temperature three-way valve (212) being connected with a left port of the cold storage unit (211);

the input end of the first low-temperature circulating pump (213) is connected with the upper output end of the first low-temperature three-way valve (212); the output end of the first low-temperature circulating pump (213) is connected with the lower left input end of the cryocooler (202);

a second low-temperature three-way valve (214), wherein the upper input end of the second low-temperature three-way valve (214) is connected with the lower right output end of the cryocooler (202); a left port of the second low-temperature three-way valve (214) is connected with a right port of the cold storage unit (211);

a medium temperature thermal storage unit (215), the medium temperature thermal storage unit (215) having a right side port and a left side port;

a first medium-temperature three-way valve (216), wherein a right port of the first medium-temperature three-way valve (216) is connected with a left port of the medium-temperature heat storage unit (215);

the input end of the first medium-temperature circulating pump (217) is connected with the upper output end of the first medium-temperature three-way valve (216); the output end of the first medium-temperature circulating pump (217) is connected with the lower input end of the air compressor unit (100);

the upper input end of the second medium-temperature three-way valve (218) is connected with the lower output end of the air compressor unit (100); the left port of the second medium-temperature three-way valve (218) is connected with the right port of the medium-temperature heat storage unit (215);

the right upper side output end of the rectifying tower (300) is connected with the left side input end of the fifth air three-way valve (209); the right upper side input end of the rectifying tower (300) is connected with the left side output end of the second air three-way valve (205); the right lower side input end of the rectifying tower (300) is connected with the lower output end of the fourth air three-way valve (208); the right lower side output end of the rectifying tower (300) is connected with the left side input end of the third air three-way valve (206);

the air power generation unit with air separation liquefaction unit sharing liquid air storage tank (207), cold storage unit (211), first low temperature three-way valve (212), second low temperature three-way valve (214), medium temperature heat-retaining unit (215), first medium temperature three-way valve (216) and second medium temperature three-way valve (218), still include:

the input end of the low-temperature booster pump (401) is connected with the output end of the liquid air storage tank (207);

the left input end of the evaporator (402) is connected with the output end of the low-temperature booster pump (401); the left output end of the evaporator (402) is connected with the lower input end of the first low-temperature three-way valve (212);

a first nitrogen three-way valve (403), wherein the left input end of the first nitrogen three-way valve (403) is connected with the right output end of the evaporator (402);

a third low-temperature three-way valve (404), wherein the upper input end of the third low-temperature three-way valve (404) is connected with the lower output end of the second low-temperature three-way valve (214); the left output end of the third low-temperature three-way valve (404) is connected with the right input end of the evaporator (402);

the input end of the second low-temperature circulating pump (405) is connected with the lower output end of the third low-temperature three-way valve (404); the output end of the second low-temperature circulating pump (405) is connected with the right input end of the evaporator (402);

the input end of the second medium-temperature circulating pump (406) is connected with the lower output end of the second medium-temperature three-way valve (218);

a third medium-temperature three-way valve (407), wherein the upper input end of the third medium-temperature three-way valve (407) is connected with the output end of the second medium-temperature circulating pump (406); the left input end of the third medium-temperature three-way valve (407) is connected with the right port of the medium-temperature heat storage unit (215);

an air turbine set (500), wherein the left input end of the air turbine set (500) is connected with the right output end of the first nitrogen three-way valve (403); the upper output end of the air turbine unit (500) is connected with the lower input end of the first medium-temperature three-way valve (216); the upper input end of the air turbine unit (500) is connected with the lower output end of the third medium-temperature three-way valve (407);

the ammonia synthesis circulation system comprises:

an air separation plant (601), the air separation plant (601) having a nitrogen output and an oxygen output;

the lower input end of the second nitrogen three-way valve (602) is connected with the nitrogen output end of the air separation plant (601); the upper output end of the second nitrogen three-way valve (602) is connected with the lower input end of the first air three-way valve (201);

a first mixing chamber (603), wherein the right input end of the first mixing chamber (603) is connected with the left output end of the second nitrogen three-way valve (602); the upper input end of the first mixing chamber (603) is connected with the right output end of the air turbine set (500);

a hydrogen gas generator (604), wherein the hydrogen gas output end of the hydrogen gas generator (604) is connected with the lower input end of the first mixing chamber (603);

the upper input end of the second mixing chamber (605) is connected with the lower output end of the first nitrogen three-way valve (403);

the right side input end of the preheater (606) is connected with the left side output end of the second mixing chamber (605);

the input end of the normal-temperature cooler (607) is connected with the right output end of the preheater (606);

the upper input end of the liquid ammonia separator (608) is connected with the output end of the normal temperature cooler (607);

an input end of the liquid ammonia throttling valve (609) is connected with a lower output end of the liquid ammonia separator (608);

the input end of the liquid ammonia storage tank (610) is connected with the output end of the liquid ammonia throttling valve (609);

a scavenging unit (611), a left input of the scavenging unit (611) being connected to a right output of the liquid ammonia separator (608); the upper output end of the scavenging unit (611) is connected with the lower input end of the second mixing chamber (605);

a hydrogen separation unit (612), wherein a left input end of the hydrogen separation unit (612) is connected with a right output end of the scavenging unit (611); the lower output end of the hydrogen separation unit (612) is connected with an external waste gas treatment unit;

a third medium temperature circulating pump (613), an input end of the third medium temperature circulating pump (613) being connected to a lower left output end of the air turbine group (500);

a high temperature heat storage unit (614), the high temperature heat storage unit (614) having an upper port and a lower port;

a first high-temperature three-way valve (615), wherein the upper port of the first high-temperature three-way valve (615) is connected with the lower port of the high-temperature heat storage unit (614);

the input end of the first high-temperature circulating pump (616) is connected with the right output end of the first high-temperature three-way valve (615);

a second high-temperature three-way valve (617), wherein the lower port of the second high-temperature three-way valve (617) is connected with the upper port of the high-temperature heat storage unit (614); the upper output end of the second high-temperature three-way valve (617) is connected with the lower right input end of the air turbine unit (500);

the output end of the second high-temperature circulating pump (618) is connected with the left input end of the first high-temperature three-way valve (615); the input end of the second high-temperature circulating pump (618) is connected with the lower middle output end of the air turbine set (500);

a mixed gas compressor set (700), wherein the right input end of the mixed gas compressor set (700) is connected with the left output end of the first mixing chamber (603); the upper output end of the mixed gas compressor unit (700) is connected with the lower middle input end of the air turbine unit (500); the upper input end of the mixed gas compressor unit (700) is connected with the output end of the third medium-temperature circulating pump (613); the left output end of the mixed gas compressor set (700) is connected with the right input end of the second mixing chamber (605); the lower input end of the mixed gas compressor unit (700) is connected with the upper output end of the hydrogen separation unit (612);

the upper input end of the ammonia synthesis unit (800) is connected with the left output end of the preheater (606); the lower output end of the ammonia synthesis unit (800) is connected with the left input end of the preheater (606); the left input end of the ammonia synthesis unit (800) is connected with the output end of the first high-temperature circulating pump (616); and the left output end of the ammonia synthesis unit (800) is connected with the right input end of the second high-temperature three-way valve (617).

2. The integrated liquid air energy storage and ammonia synthesis plant according to claim 1, characterized in that said air compressor group (100) comprises one or more stages of air compressors and air coolers; the air turbine set (500) comprises a one-stage or multi-stage medium-temperature heater, a high-temperature heater, a turbine and a medium-temperature three-way valve; the mixed gas compressor set (700) comprises one or more stages of mixed gas compressors and mixed gas coolers; the ammonia synthesis unit (800) comprises one or more stages of ammonia reactors and ammonia coolers.

3. The integrated device for liquid air energy storage and ammonia synthesis according to claim 1, characterized in that said rectifying column (300) comprises:

a high pressure chamber (301), said high pressure chamber (301) having an upper input, an upper output, a lower output, an upper right input and a lower right input; the right upper side input end of the high-pressure chamber (301) is connected with the right upper side input end of the rectifying tower (300); the right lower side input end of the high-pressure chamber (301) is connected with the right lower side input end of the rectifying tower (300);

a filler (302), the filler (302) being located inside the high pressure chamber (301);

the input end of the liquid oxygen throttle valve (303) is connected with the lower output end of the high-pressure chamber (301);

a low pressure chamber (304), the low pressure chamber (304) being located on top of the high pressure chamber (301); the left input end of the low-pressure chamber (304) is connected with the output end of the liquid oxygen throttle valve (303); the upper output end of the low-pressure chamber (304) is connected with the upper right output end of the rectifying tower (300);

an evaporative condenser (305), the evaporative condenser (305) located inside the low pressure chamber (304); the input end of the evaporative condenser (305) is connected with the upper output end of the high-pressure chamber (301); the output end of the evaporative condenser (305) is divided into two paths: one path is connected with the upper input end of the high-pressure chamber (301), and the other path is connected with the right lower output end of the rectifying tower (300).

4. The integrated device for liquid air energy storage and ammonia synthesis as claimed in claim 1, wherein the cold storage unit (211), the medium temperature heat storage unit (215) and the high temperature heat storage unit (614) respectively adopt latent heat, sensible heat or thermochemical energy storage materials with working temperature ranges of at least-195-20 ℃, 20-300 ℃ and 20-500 ℃, operate in single-stage or multi-stage series, and adopt heat insulation materials for heat insulation.

5. The integrated device for liquid air energy storage and ammonia synthesis according to claim 1, wherein the air separation liquefaction unit uses air or nitrogen as a working medium; the heat transfer fluid of the cold storage unit (211) is methanol, propane or air; the heat transfer fluid of the medium-temperature heat storage unit (215) is heat conduction oil or silicone oil; the heat transfer fluid of the high-temperature heat storage unit (614) is molten salt; the hydrogen generator (604) is an electrolytic water tank or a fossil fuel hydrogen production device.

6. An integrated method for liquid air energy storage and ammonia synthesis by using the device of any one of claims 1 to 5, wherein during the electricity consumption valley period, the air separation liquefaction unit and the ammonia synthesis circulation system work, and the device operates in two modes:

in the first mode, one part of gaseous nitrogen produced by the air separation plant (601) is supplied to the air separation liquefaction unit to acquire and store liquid nitrogen, and the other part of gaseous nitrogen is supplied to the ammonia synthesis circulation system, and the method specifically comprises the following steps:

air separation liquefaction unit: a part of gaseous nitrogen produced by an air separation plant (601) enters an air compressor unit (100) through a second nitrogen three-way valve (602) and a first air three-way valve (201), the gaseous nitrogen is compressed to high pressure, and meanwhile, compression heat generated in the compression process is recovered and stored in a medium-temperature heat storage unit (215); high-pressure gaseous nitrogen at the outlet of the air compressor unit (100) enters a low-temperature cooler (202), is cooled to low temperature by low-temperature cold energy stored in a cold storage unit (211) and returned gaseous nitrogen, then enters a low-temperature turboexpander (203) to be expanded and depressurized, wherein a part of gaseous nitrogen is liquefied, and gaseous and liquid nitrogen are separated by a liquid air separator (204): the liquid nitrogen enters a liquid air storage tank (207) through a second air three-way valve (205) and a third air three-way valve (206), and the gaseous nitrogen enters the air compressor unit (100) through a fourth air three-way valve (208), a fifth air three-way valve (209), a cryocooler (202) and a sixth air three-way valve (210);

an ammonia synthesis circulating system: the other part of gaseous nitrogen produced by the air separation plant (601) enters a first mixing chamber (603) through a second nitrogen three-way valve (602), is fully mixed with the hydrogen produced by a hydrogen generator (604), enters a mixed gas compressor unit (700) to be pressurized to the medium pressure, is mixed with unreacted hydrogen recycled by a hydrogen separation unit (612) and is further pressurized to the high pressure, and meanwhile, compression heat generated in the compression process is recycled and stored in a medium-temperature heat storage unit (215); high-pressure gas at the outlet of the mixed gas compressor unit (700) enters a second mixing chamber (605), is fully mixed with unreacted gas recovered from the scavenging unit (611), enters an ammonia synthesis unit (800) to synthesize ammonia after being preheated by a preheater (606), and simultaneously stores reaction heat generated in the ammonia synthesis reaction process in a high-temperature heat storage unit (614); the mixed gas after the reaction is cooled to normal temperature sequentially through a preheater (606) and a normal temperature cooler (607), ammonia gas in the mixed gas is condensed, and then the mixed gas enters a liquid ammonia separator (608) to separate liquid ammonia and unreacted gas: liquid ammonia enters a liquid ammonia storage tank (610) after throttling and pressure reduction through a liquid ammonia throttle valve (609), unreacted gas passes through a scavenging unit (611) and a hydrogen separation unit (612) in sequence to complete scavenging and hydrogen recovery, and then is discharged finally;

in a second mode, the air separation liquefaction unit separates and liquefies nitrogen from air, one part of liquid nitrogen is stored in a liquid air storage tank (207), and the other part of liquid nitrogen is pressurized and preheated and then is supplied to an ammonia synthesis circulation system, and the method specifically comprises the following steps:

air separation liquefaction unit: after being purified, ambient air enters an air compressor unit (100) through a first air three-way valve (201) to be pressurized to high pressure, and meanwhile, compression heat generated in the air compression process is recovered and stored in a medium-temperature heat storage unit (215); the high-pressure air at the outlet of the air compressor unit (100) passes through the low-temperature cooler (202), is cooled to low temperature by the low-temperature cold energy stored in the cold storage unit (211) and the returned oxygen-enriched air, enters the low-temperature turbo expander (203) for expansion and pressure reduction, wherein a part of air is liquefied, and then enters the liquid air separator (204) for separating gaseous air and liquid air: liquid air enters a high-pressure chamber (301) of the rectifying tower (300) through a second air three-way valve (205) and is sprayed from top to bottom, and gaseous air enters the high-pressure chamber (301) of the rectifying tower (300) through a fourth air three-way valve (208) and is blown from bottom to top; the gaseous air and the liquid air complete heat and mass exchange in the packing (302), the high-purity gaseous nitrogen is gathered at the top of the high-pressure chamber (301), and the oxygen-enriched liquid air is gathered at the bottom of the high-pressure chamber (301); oxygen-enriched liquid air at the bottom of the high-pressure chamber (301) is cooled and depressurized through the liquid oxygen throttle valve (303), enters the low-pressure chamber (304) to release cold energy and is changed into gaseous oxygen-enriched air, and then is discharged into the environment through the fifth air three-way valve (209), the cryocooler (202) and the sixth air three-way valve (210); high-purity gaseous nitrogen at the top of the high-pressure chamber (301) enters an evaporative condenser (305) of the low-pressure chamber (304), oxygen-enriched liquid air after being throttled and depressurized is condensed into liquid nitrogen, a part of liquid nitrogen flows back to the high-pressure chamber (301) for spraying, and the other part of liquid nitrogen enters a liquid air storage tank (207) through a third air three-way valve (206); one part of liquid nitrogen in the liquid air storage tank (207) is stored, the other part of the liquid nitrogen is pressurized by a low-temperature pressurizing pump (401) and then enters an evaporator (402) for preheating, and meanwhile, released cold energy is stored in a cold storage unit (211); the normal-temperature high-pressure gaseous nitrogen at the outlet of the evaporator (402) is supplied to the ammonia synthesis circulating system through a first nitrogen three-way valve (403);

an ammonia synthesis circulating system: hydrogen produced by a hydrogen generator (604) enters a mixed gas compressor unit (700) through a first mixing chamber (603), is primarily compressed to medium pressure, then is mixed with unreacted hydrogen recovered from a hydrogen separation unit (612), is further compressed to high pressure, and simultaneously recovers compression heat generated in the hydrogen compression process and stores the compression heat in a medium-temperature heat storage unit (215); high-pressure hydrogen at the outlet of the mixed gas compressor unit (700) enters a second mixing chamber (605), is fully mixed with high-pressure nitrogen supplied by a liquid air storage tank (207) and unreacted gas recovered by a scavenging unit (611), is preheated by a preheater (606) and enters an ammonia synthesis unit (800) to complete ammonia synthesis reaction, and meanwhile, reaction heat is recovered and stored in a high-temperature heat storage unit (614); the fully reacted mixed gas is cooled to normal temperature through a preheater (606) and a normal temperature cooler (607) in sequence, ammonia gas in the mixed gas is condensed, and then the mixed gas enters a liquid ammonia separator (608) to separate liquid ammonia and unreacted gas: liquid ammonia enters a liquid ammonia storage tank (610) after throttling and pressure reduction through a liquid ammonia throttle valve (609), and unreacted gas is discharged finally after completing scavenging and hydrogen recovery through a scavenging unit (611) and a hydrogen separation unit (612) in sequence.

7. The integrated method for liquid air energy storage and ammonia synthesis as claimed in claim 6, wherein in the electricity consumption valley period, when the air separation plant (601) is unavailable, the air separation liquefaction unit separates and liquefies nitrogen from air by using the rectifying tower (300), one part is stored, and the other part is supplied to the ammonia synthesis circulation system; when the air separation plant (601) is available, the air separation liquefaction unit directly liquefies and stores gaseous nitrogen provided by the air separation plant (601).

8. The integrated method for liquid air energy storage and ammonia synthesis by using the device of any one of claims 1 to 5, wherein the air power generation unit and the ammonia synthesis circulation system work during peak electricity utilization period, and the method comprises the following steps:

an air power generation unit: liquid nitrogen stored in a liquid air storage tank (207) is pressurized to high pressure through a low-temperature pressurizing pump (401), then enters an evaporator (402) to be preheated, the liquid nitrogen is evaporated and vaporized into gaseous nitrogen, and cold energy released by evaporation of the liquid nitrogen is stored in a cold storage unit (211); the normal-temperature high-pressure gaseous nitrogen at the outlet of the evaporator (402) is divided into two paths through a first nitrogen three-way valve (403): one part of the mixed gas enters a second mixing chamber (605) to be supplied to an ammonia synthesis circulation system, the other part of the mixed gas enters an air turbine unit (500), is subjected to two-stage preheating and then is subjected to expansion power generation, and then enters a first mixing chamber (603) to be supplied to the ammonia synthesis circulation system;

an ammonia synthesis circulating system: hydrogen produced by a hydrogen generator (604) enters a first mixing chamber (603), is fully mixed with nitrogen at the outlet of an air turbine unit (500), then enters a mixed gas compressor unit (700) for preliminary compression to medium pressure, is further compressed to high pressure after being mixed with unreacted hydrogen recycled by a hydrogen separation unit (612), and meanwhile, compression heat generated in the compression process is recycled for preliminary preheating of nitrogen in the air turbine unit (500); high-pressure gas at the outlet of the mixed gas compressor unit (700) enters a second mixing chamber (605), is fully mixed with a part of nitrogen shunted at the outlet of the evaporator (402) and unreacted gas recovered in the scavenging unit (611), enters an ammonia synthesis unit (800) to synthesize ammonia after being preheated by a preheater (606), and simultaneously recovers reaction heat generated in the ammonia synthesis reaction process for further preheating the nitrogen in the air turbine unit (500); the mixed gas after the reaction is cooled to normal temperature sequentially through a preheater (606) and a normal temperature cooler (607), ammonia gas in the mixed gas is condensed, and then the mixed gas enters a liquid ammonia separator (608) to separate liquid ammonia and unreacted gas: liquid ammonia enters a liquid ammonia storage tank (610) after being throttled and depressurized by a liquid ammonia throttle valve (609), and unreacted gas is discharged finally after being subjected to scavenging and hydrogen recovery by a scavenging unit (611) and a hydrogen separation unit (612) in sequence.

9. The integrated method for liquid air energy storage and ammonia synthesis of claim 8, wherein during peak electricity consumption periods, the air turbine set (500) preheats nitrogen to medium temperature primarily by using the heat of compression stored by the medium temperature heat storage unit (215) and the heat of compression generated by the mixed gas compressor set (700) in real time, and then preheats nitrogen to high temperature further by using the heat of reaction stored by the high temperature heat storage unit (614) and the heat of reaction generated by the ammonia synthesis unit (800) in real time, so as to improve the power generation and the efficiency of the liquid air energy storage circulation system; when the heat demand of the air turbine unit (500) is reduced, the excess compression heat generated in real time by the mixed gas compressor unit (700) can be stored in the medium-temperature heat storage unit (215), and the excess reaction heat generated in real time by the ammonia synthesis unit (800) can be stored in the high-temperature heat storage unit (614).

10. The integrated liquid air energy storage and ammonia synthesis method according to claim 8, wherein during peak electricity consumption, the air power generation unit in the liquid air energy storage circulation system provides nitrogen to the ammonia synthesis circulation system in two ways: the first method is that liquid nitrogen stored in a liquid air storage tank (207) is pressurized, preheated, expanded and generated and then is supplied to an ammonia synthesis circulating system, and the operation of the liquid air energy storage circulating system is not influenced; the second method is that liquid nitrogen stored in a liquid air storage tank (207) is pressurized to the pressure required by the ammonia synthesis reaction, and then heated and vaporized to be supplied to an ammonia synthesis circulation system, so that the power consumption of mixed gas compression in a mixed gas compressor unit (700) is reduced.

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