Cross-season and night composite cold storage air conditioning system based on low-temperature grain storage

Abstract

The utility model discloses a cross-seasonal and night composite cold storage air conditioning system based on low-temperature grain storage, which comprises a night cold storage system, a cooling capacity pickup heat exchanger, a cold release heat exchanger, a gas-liquid separator, a gas recovery tank and the like. By adjusting the on-off states of electromagnetic valves of the cooling capacity picking heat exchanger and the cooling capacity preparing heat exchanger, the distribution between cold storage by utilizing the environment temperature and cold storage by preparing the cooling capacity at night is realized; according to the principle that cold in winter and used in summer, cold storage is conducted in winter, cold release is conducted in a granary in summer, and when the cold storage capacity is insufficient, night cold storage is started to supplement the cold storage capacity, so that the cold storage capacity is stably supplied, the operation stability of the system is guaranteed, and meanwhile the equipment capacity and the initial investment of the cold storage system are reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of low-temperature grain storage systems, and in particular relates to a cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage. Background Art

[0002] Low-temperature grain storage is recognized as an ideal green grain storage technology. This technology uses refrigeration equipment to maintain the average temperature of the grain pile below 15°C, and the local maximum temperature is not higher than 20°C. At this temperature, the basal metabolic rate of grain drops significantly, various indicators remain stable, the growth and reproduction of microorganisms are inhibited, and the grain storage time is increased from 2-3 years to 3-5 years. The direct loss rate of grain caused by factors such as aging and mildew is reduced from 8% to 3%, and the shelf life and storage period of grain are increased. The harm that chemical agents may cause to the human body is greatly reduced, and food safety is guaranteed. However, the refrigeration equipment used in low-temperature grain storage consumes huge electricity costs and incidental carbon emissions during operation, resulting in it not being widely used in the actual grain storage process. According to statistics, the idle rate of grain coolers, air conditioners and other equipment specially used for mechanical refrigeration of grain warehouses exceeds 50%. One of the important reasons is that the refrigeration equipment required to maintain the temperature and humidity conditions of the grain warehouse has high operating power and high energy consumption. Therefore, accelerating the improvement of low-temperature grain storage technology and improving storage efficiency is the key to strengthening grain storage loss reduction.

[0003] At present, in view of the high operating power and high energy consumption of traditional refrigeration equipment, the cross-season cold storage system is an effective solution. For example, CN115264679A discloses a cross-season cold storage system using CO2 hydrate as a cold storage material. The system stores the natural cold energy in winter and releases it in summer to provide cold for the granary, greatly reducing energy consumption and carbon emissions. However, if the summer cooling of the granary is met entirely by the cross-season cold storage system, a huge cold storage volume will be required, the investment cost will be large, and it will be difficult to guarantee the cooling demand throughout the summer due to the randomness of meteorological conditions. In view of this situation, the use of a cross-season and nighttime composite cold storage air conditioning system is an effective way to reduce the operating energy consumption and cost of granary refrigeration equipment. The cross-season and nighttime composite cold storage air conditioning systems are combined to store cold during the low electricity price at night, and release cold during the day to meet the cooling demand, reduce operating costs, and facilitate the reasonable scheduling of the power grid. Utility Model Content

[0004] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a cross-seasonal and night-time composite cold storage air-conditioning system based on low-temperature grain storage, which adopts CO2 hydrate as the cold storage medium, utilizes the combination of "peak shaving and valley filling" and "winter cooling and summer use", stores winter cold and nighttime cold storage cold in a low operating cost and environmentally friendly way, which is used for low-temperature control of granaries, provides continuous air conditioning and air supply to the grain storage space, and realizes low-temperature grain storage.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage, including a nighttime cold storage system, a cold pickup heat exchanger, a cold release heat exchanger, a gas-liquid separator, a gas recovery tank, a gas pressurizer, a solution recovery tank, a hydrate generation tank, and a hydrate storage tank; the hydrate generation tank and the hydrate storage tank are both pre-buried below the ground, the cold release heat exchanger is arranged in the granary, and the cold pickup heat exchanger is placed outdoors; the hydrate generation tank is equipped with a cold storage heat exchanger, the cold pickup heat exchanger and the cold storage heat exchanger are connected through a pipeline to form a cooling cycle, and a first fluid pump and a first solenoid valve are sequentially installed on the pipeline between the outlet of the cold storage heat exchanger and the inlet of the cold pickup heat exchanger;

[0006] The nighttime cold storage system is composed of a compressor, a condenser, an electronic expansion valve, and a cold production heat exchanger. The outlet of the compressor is connected to the inlet of the condenser through a pipeline, and the inlet of the compressor is connected to the outlet 1 of the cold production heat exchanger through a pipeline; the outlet of the condenser is connected to the inlet 1 of the cold production heat exchanger through a pipeline, and an electronic expansion valve is arranged on the pipeline; the inlet 2 of the cold production heat exchanger is connected to the pipeline connecting the first solenoid valve and the first fluid pump through a branch pipeline, and a ninth solenoid valve is arranged on the branch pipeline; the outlet 2 of the cold production heat exchanger is connected to the pipeline connecting the outlet of the cold pickup heat exchanger and the inlet of the cold storage heat exchanger through a branch pipeline;

[0007] The outlet of the hydrate generation tank is connected to the inlet of the hydrate storage tank by a pipeline, and a second fluid pump and a second solenoid valve are sequentially arranged on the pipeline; the inlet of the cold-releasing heat exchanger is connected to the outlet of the hydrate storage tank by a pipeline, and a third solenoid valve and a third fluid pump are sequentially arranged on the pipeline; the inlet of the gas-liquid separator is connected to the outlet of the cold-releasing heat exchanger by a pipeline, and the gas outlet of the gas-liquid separator is connected to the inlet of the gas recovery tank by a pipeline, and a sixth solenoid valve is arranged on the pipeline; the inlet of the solution recovery tank is connected to the slurry outlet below the gas-liquid separator by a pipeline, and a fourth solenoid valve is arranged on the pipeline; the outlet of the solution recovery tank is connected to the hydrate generation tank by a pipeline, and a fourth fluid pump and a fifth solenoid valve are sequentially arranged on the pipeline; the inlet of the gas compressor is connected to the outlet of the gas recovery tank by a pipeline; the outlet of the gas compressor is connected to the hydrate generation tank and the hydrate storage tank respectively through pipelines.

[0008] Preferably, a first stirring motor is arranged on the top of the hydrate generation tank, the stirring shaft of the first stirring motor passes through the interior of the hydrate generation tank and a first stirring blade is connected to the end of the stirring shaft; a second stirring motor is arranged on the top of the hydrate storage tank, the stirring shaft of the second stirring motor passes through the interior of the hydrate storage tank and a second stirring blade is connected to the end of the stirring shaft.

[0009] Preferably, the cold picking up heat exchanger is provided with a first fan, and the first fan cooperates with the cold picking up heat exchanger to exchange heat with outdoor cold air to achieve cold picking; the cold releasing heat exchanger is provided with a second fan, and the second fan cooperates with the cold releasing heat exchanger to exchange heat with the air in the granary to achieve cold release; the condenser is provided with a third fan to accelerate the heat dissipation of the condenser.

[0010] Preferably, a first nozzle is arranged above the interior of the hydrate formation tank, and the first nozzle is connected to the outlet of the gas compressor through a pipeline, and a seventh solenoid valve is arranged on the pipeline; the pipeline between the seventh solenoid valve and the first nozzle is connected to the inlet of the gas generator built into the bottom of the hydrate formation tank through a branch pipeline; the pipeline between the seventh solenoid valve and the gas compressor is connected to the second nozzle built above the hydrate storage tank through a branch pipeline, and an eighth solenoid valve is arranged on the branch pipeline.

[0011] Preferably, the hydrate generation tank and the hydrate storage tank are both provided with a thermal insulation layer.

[0012] The beneficial effects of the utility model are:

[0013] The utility model takes the cross-season and nighttime composite cold storage air-conditioning system as the research object, combines the electric energy refrigeration technology and the phase change cold storage technology, and proposes a novel "cross-season and nighttime" composite cold storage system for granaries; the system can realize the switching between different working conditions by controlling the on-off of the electromagnetic valves of each branch, and realizes the distribution between the cold storage by utilizing the ambient temperature and the cold storage by producing cold at night by adjusting the on-off of the electromagnetic valves of the cold picking heat exchanger and the cold making heat exchanger; specifically, it utilizes the principle of "winter cooling and summer use", stores cold in winter, and releases cold inside the granary in summer, and when the cold storage is insufficient, starts the nighttime cold storage to supplement the cold storage, so as to stably supply cold, ensure the stability of system operation, and at the same time reduce the equipment capacity and initial investment of the cold storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the utility model;

[0015] In the figure: 1, cold picking heat exchanger; 2, first fan; 3, cold storage heat exchanger; 4, first fluid pump; 5, first solenoid valve; 6, hydrate generation tank; 7, second fluid pump; 8, second solenoid valve; 9, hydrate storage tank; 10, third fluid pump; 11, third solenoid valve; 12, cold release heat exchanger; 13, second fan; 14, gas-liquid separator; 15, fourth solenoid valve; 16, solution recovery tank; 17, fourth fluid pump; 18, fifth solenoid valve; 19, Six solenoid valves; 20. Gas recovery tank; 21. Gas compressor; 22. Seventh solenoid valve; 23. First one-way gas nozzle; 24. Eighth solenoid valve; 25. Second one-way gas nozzle; 26. Gas generator; 27. First stirring motor; 28. First stirring blade; 29. ​​Second stirring motor; 30. Second stirring blade; 31. Compressor; 32. Condenser; 33. Third fan; 34. Electronic expansion valve; 35. Cold production heat exchanger; 36. Ninth solenoid valve. DETAILED DESCRIPTION

[0016] The utility model is further described below through the accompanying drawings and specific embodiments:

[0017] See also Figure 1 A cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage, comprising a nighttime cold storage system, a cold picking heat exchanger 1, a cold releasing heat exchanger 12, a gas-liquid separator 14, a gas recovery tank 20, a gas pressurizer 21, a solution recovery tank 16, a hydrate generation tank 6, and a hydrate storage tank 9; the hydrate generation tank 6 and the hydrate storage tank 9 are both pre-buried below the ground and both are provided with a thermal insulation layer, the cold releasing heat exchanger 12 is arranged in a granary, the cold picking heat exchanger 1 is placed outdoors and is equipped with a first fan 2; the hydrate generation tank 6 is equipped with a cold storage heat exchanger 3, the cold picking heat exchanger 1 and the cold storage heat exchanger 3 are connected by a pipeline to form a cooling cycle utilizing a natural cold source, and a first fluid pump 4 and a first solenoid valve 5 are sequentially installed on the pipeline between the outlet of the cold storage heat exchanger 3 and the inlet of the cold picking heat exchanger 1;

[0018] The nighttime cold storage system is composed of a compressor 31, a condenser 32, an electronic expansion valve 34, and a cold production heat exchanger 35. The condenser 32 is provided with a third fan 33; the outlet of the compressor 31 is connected to the inlet of the condenser 32 through a pipeline, and the inlet of the compressor 31 is connected to the outlet 1 of the cold production heat exchanger 35 through a pipeline; the outlet of the condenser 32 is connected to the inlet 1 of the cold production heat exchanger 35 through a pipeline, and an electronic expansion valve 34 is provided on the pipeline; the inlet 2 of the cold production heat exchanger 35 is connected to the pipeline connecting the first solenoid valve 5 and the first fluid pump 4 through a branch pipeline, and a ninth solenoid valve 36 is provided on the branch pipeline; the outlet 2 of the cold production heat exchanger 35 is connected to the pipeline connecting the outlet of the cold pickup heat exchanger 1 and the inlet of the cold storage heat exchanger 3 through a branch pipeline;

[0019] The outlet of the hydrate generation tank 6 is connected to the inlet of the hydrate storage tank 9 by a pipeline, and a second fluid pump 7 and a second solenoid valve 8 are sequentially arranged on the pipeline; a first stirring motor 27 is arranged on the top of the hydrate generation tank 6, and the stirring shaft of the first stirring motor 27 passes through the inside of the hydrate generation tank 6 and a first stirring blade 28 is connected to the end of the stirring shaft; a second stirring motor 29 is arranged on the top of the hydrate storage tank 9, and the stirring shaft of the second stirring motor 29 passes through the inside of the hydrate storage tank 9 and a second stirring blade 30 is connected to the end of the stirring shaft; the outlet of the hydrate storage tank 9 is connected to the inlet of the cold release heat exchanger 12 by a pipeline, and a third fluid pump 10 is sequentially arranged on the pipeline. , a third solenoid valve 11; a second fan 13 is provided on the cold release heat exchanger 12; the inlet of the gas-liquid separator 14 is connected to the outlet of the cold release heat exchanger 12 through a pipeline, the upper gas outlet of the gas-liquid separator 14 is connected to the inlet of the gas recovery tank 20 through a pipeline, and a sixth solenoid valve 19 is provided on the pipeline; the slurry outlet below the gas-liquid separator 14 is connected to the inlet of the solution recovery tank 16 through a pipeline, and a fourth solenoid valve 15 is provided on the pipeline; the outlet of the solution recovery tank 16 is connected to the hydrate generation tank 6 through a pipeline, and a fourth fluid pump 17 and a fifth solenoid valve 18 are provided on the pipeline in sequence; the inlet of the gas compressor 21 is connected to the outlet of the gas recovery tank 20 through a pipeline;

[0020] A first nozzle 23 is arranged above the inside of the hydrate forming tank 6, and the first nozzle 23 is connected to the outlet of the gas compressor 21 through a pipeline, and a seventh solenoid valve 22 is arranged on the pipeline; the pipeline between the seventh solenoid valve 22 and the first nozzle 23 is connected to the inlet of the gas generator 26 built into the bottom of the hydrate forming tank 6 through a branch pipeline; the pipeline between the seventh solenoid valve 22 and the gas compressor 21 is connected to the second nozzle 25 built into the top of the hydrate storage tank 9 through a branch pipeline, and an eighth solenoid valve 24 is arranged on the branch pipeline.

[0021] The working principle of the utility model is as follows: in winter or when the outdoor temperature is lower than the CO2 hydrate production temperature, the first fluid pump 4 and the first solenoid valve 5 are turned on, the cold energy of the outdoor environment is absorbed by the cold energy pickup heat exchanger 1, the first fluid pump 4 is used to circulate the refrigerant, and the cold energy is transferred to the cold storage heat exchanger 3 to cool the hydrate, and the gas compressor 21 provides high-pressure CO2 gas to the hydrate generation tank 6 through the first one-way gas nozzle 23 and the gas generator 26. The upper and lower air inlets are combined to increase the contact area between the CO2 gas and the solution, and the first stirring motor 27 drives the first stirring blade 28 to stir, thereby promoting CO2 hydrate is generated in the hydrate generation tank 6; after the preparation of CO2 hydrate is completed, the second fluid pump 7 and the second solenoid valve 8 are opened to transport the CO2 hydrate generated in the hydrate generation tank to the hydrate storage tank 9 for storage of cold energy. In the early stage of the storage process, the gas compressor 21 sprays high-pressure CO2 gas through the second one-way gas nozzle 25 to ensure that the pressure in the hydrate storage tank 9 meets the hydrate storage demand. At the same time, the second stirring motor 29 is intermittently turned on to drive the second stirring blade 30 to stir the CO2 hydrate to avoid agglomeration of the CO2 hydrate slurry, which is beneficial to the transportation of the CO2 hydrate slurry; When the granary needs cooling in summer, the third solenoid valve 11 is opened, and the CO2 hydrate slurry is transported to the cooling heat exchanger 12 through the third fluid pump 10 for CO2 hydrate dissociation and cooling, thereby releasing the stored cold and realizing cross-seasonal storage and transfer of cold; after the CO2 hydrate is cooled and dissociated, it is passed into the gas-liquid separator 14, and the slurry part flows into the solution recovery tank 16, and is transported to the hydrate generation tank 6 for recovery through the fourth fluid pump 17, and the gas part is collected by the gas recovery tank 20, and is pressurized by the gas compressor 21 and then re-introduced into the hydrate generation tank 6 to prepare CO2 hydrate; when the cold storage capacity is insufficient, the ... closed. The first solenoid valve 5 opens the ninth solenoid valve 36, activates the first fluid pump 4, and starts the nighttime cold storage system at the same time, opens the compressor 31 to compress the refrigerant and generate high-temperature and high-pressure gas, cools the gas compressed by the compressor through the condenser 32, and uses the electronic expansion valve 34 to adjust the flow and control the superheat. The low-pressure refrigerant coming out of the electronic expansion valve evaporates and absorbs heat in the cold energy production heat exchanger 35, and cools the refrigerant circulating in the first fluid pump 4, thereby providing cold energy for the hydrate generation in the hydrate generation tank 6, and then utilizing the low electricity price at night to store cold energy, thereby ensuring the stability of system operation.

[0022] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage, characterized in that: It includes a nighttime cold storage system, a cold picking heat exchanger, a cold releasing heat exchanger, a gas-liquid separator, a gas recovery tank, a gas pressurizer, a solution recovery tank, a hydrate generation tank, and a hydrate storage tank; the hydrate generation tank and the hydrate storage tank are both pre-buried below the ground, the cold releasing heat exchanger is arranged in the granary, and the cold picking heat exchanger is placed outdoors; the hydrate generation tank is equipped with a cold storage heat exchanger, the cold picking heat exchanger and the cold storage heat exchanger are connected with each other through a pipeline to form a cold supply cycle, and a first fluid pump and a first solenoid valve are sequentially installed on the pipeline between the outlet of the cold storage heat exchanger and the inlet of the cold picking heat exchanger; The nighttime cold storage system is composed of a compressor, a condenser, an electronic expansion valve, and a cold production heat exchanger. The outlet of the compressor is connected to the inlet of the condenser through a pipeline, and the inlet of the compressor is connected to the outlet 1 of the cold production heat exchanger through a pipeline; the outlet of the condenser is connected to the inlet 1 of the cold production heat exchanger through a pipeline, and an electronic expansion valve is arranged on the pipeline; the inlet 2 of the cold production heat exchanger is connected to the pipeline connecting the first solenoid valve and the first fluid pump through a branch pipeline, and a ninth solenoid valve is arranged on the branch pipeline; the outlet 2 of the cold production heat exchanger is connected to the pipeline connecting the outlet of the cold pickup heat exchanger and the inlet of the cold storage heat exchanger through a branch pipeline; The outlet of the hydrate generation tank is connected to the inlet of the hydrate storage tank by a pipeline, and a second fluid pump and a second solenoid valve are sequentially arranged on the pipeline; the outlet of the hydrate storage tank is connected to the inlet of the cold-releasing heat exchanger by a pipeline, and a third fluid pump and a third solenoid valve are sequentially arranged on the pipeline; the inlet of the gas-liquid separator is connected to the outlet of the cold-releasing heat exchanger by a pipeline, and the upper gas outlet of the gas-liquid separator is connected to the inlet of the gas recovery tank by a pipeline, and a sixth solenoid valve is arranged on the pipeline; the slurry outlet below the gas-liquid separator is connected to the inlet of the solution recovery tank by a pipeline, and a fourth solenoid valve is arranged on the pipeline; the outlet of the solution recovery tank is connected to the hydrate generation tank by a pipeline, and a fourth fluid pump and a fifth solenoid valve are sequentially arranged on the pipeline; the inlet of the gas compressor is connected to the outlet of the gas recovery tank by a pipeline; the outlet of the gas compressor is connected to the hydrate generation tank and the hydrate storage tank respectively through pipelines.

2. The cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage according to claim 1 is characterized in that: A first stirring motor is arranged on the top of the hydrate generation tank, and a stirring shaft of the first stirring motor passes through the interior of the hydrate generation tank and a first stirring blade is connected to the end of the stirring shaft; a second stirring motor is arranged on the top of the hydrate storage tank, and a stirring shaft of the second stirring motor passes through the interior of the hydrate storage tank and a second stirring blade is connected to the end of the stirring shaft.

3. The cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage according to claim 1 is characterized in that: The cold picking heat exchanger is provided with a first fan, the cold releasing heat exchanger is provided with a second fan, and the condenser is provided with a third fan.

4. The cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage according to claim 1 is characterized in that: A first nozzle is arranged above the inside of the hydrate generation tank, and the first nozzle is connected to the outlet of the gas compressor through a pipeline, and a seventh solenoid valve is arranged on the pipeline; the pipeline between the seventh solenoid valve and the first nozzle is connected to the inlet of the gas generator built into the bottom of the hydrate generation tank through a branch pipeline; the pipeline between the seventh solenoid valve and the gas compressor is connected to the second nozzle built above the hydrate storage tank through a branch pipeline, and an eighth solenoid valve is arranged on the branch pipeline.

5. The cross-seasonal and nighttime composite cold storage air conditioning system based on low-temperature grain storage according to claim 1 is characterized in that: The hydrate generation tank and the hydrate storage tank are both provided with a thermal insulation layer.

Images