A waste heat recovery system for a large cold storage refrigeration system

Abstract

This utility model discloses a waste heat recovery system for a large-scale cold storage refrigeration system, which can utilize the waste heat generated by the large cold storage in multiple scenarios, improve the waste heat recovery efficiency, and ensure stable operation. It is also compatible with the original cold storage, reducing operating costs. The system includes a hot refrigerant defrosting system for a cold air blower, a hot water defrosting system for a cold air blower, and a floor heating system. The hot refrigerant defrosting system for a cold air blower includes a cold air blower with a coil inside. The coil is connected to the return air fins, and the coil inlet is connected to the main refrigerant exhaust pipe via a refrigerant exhaust branch pipe. The main refrigerant exhaust pipe is connected to an oil separator, and the oil separator is connected to a compressor. The hot water defrosting system includes a cold air blower, a defrosting water heat exchanger, a first heat recovery water pump, a defrosting water tank, and a defrosting water pump. The floor heating system includes a floor heating heat exchanger, a second heat recovery water pump, an ethylene glycol supply collector, an ethylene glycol return collector, and floor heating pipes.

Description

Technical Field

[0001] This utility model relates to the field of cold storage heat recovery technology, and in particular to a waste heat recovery system for a large-scale cold storage refrigeration system. Background Technology

[0002] With the development of the global economy, cold storage is increasingly widely used in food storage, cold chain logistics, and other fields. However, cold storage consumes a large amount of energy during operation, and if the waste heat generated by its refrigeration system is directly discharged without treatment, it not only wastes energy but may also cause thermal pollution to the surrounding environment, which runs counter to the current trend of energy conservation, emission reduction, and sustainable development. In the traditional operation mode of large cold storage (cold storage with a building area of ​​not less than 1,000 square meters), the refrigeration system maintains a low-temperature environment through compression, condensation, expansion, and evaporation. The refrigeration system mainly includes an evaporator, compressor, condenser, and throttling device. In the refrigeration cycle, the refrigerant absorbs heat in the evaporator and is converted into a low-temperature, low-pressure gas, which returns to the compressor. The compressor compresses the low-temperature, low-pressure gas into a high-temperature, high-pressure gas and sends it into the condenser through the exhaust pipe. The high-temperature, high-pressure refrigerant gas is cooled in the condenser, releasing heat (which is equal to the sum of the refrigeration capacity and the compression work) to the external environment, completing the heat exchange process. During compressor operation, electrical energy is converted into mechanical and thermal energy. Furthermore, the refrigerant releases a significant amount of heat as it changes from a gaseous to a liquid state in the condenser. This waste heat is typically dissipated into the environment along with the cooling medium (such as air or water), resulting in substantial energy waste. Against this backdrop, waste heat recovery and energy-saving technologies have emerged. These technologies utilize a series of heat recovery devices and processes to collect the waste heat generated by the refrigeration system, achieving energy recycling and energy conservation goals.

[0003] Currently, most waste heat recovery technologies on the market focus on single application scenarios (such as kitchen water heating, floor heating, etc.), which are mainly suitable for small cold storage facilities. For large cold storage facilities, single-scenario waste heat recovery cannot meet energy-saving requirements and the waste heat recovery efficiency is not high. How to improve the waste heat recovery efficiency of large cold storage facilities, increase energy utilization, and ensure the stable operation of the waste heat recovery system are key issues to be considered in the waste heat recovery of large cold storage facilities. Utility Model Content

[0004] One of the objectives of this utility model is, at least, to address the problems existing in the prior art by providing a waste heat recovery system for a large-scale cold storage refrigeration system. This system can utilize the waste heat generated by the large-scale cold storage in multiple scenarios, improve waste heat recovery efficiency, and ensure stable operation of the waste heat recovery system. It is also compatible with the original cold storage and reduces operating costs.

[0005] To achieve the above objectives, the technical solution adopted by this utility model includes the following aspects.

[0006] A waste heat recovery system for a large cold storage refrigeration system includes a hot refrigerant defrosting system for air coolers, a hot water defrosting system for air coolers, and a floor heating system. The hot refrigerant defrosting system for the air cooler includes an air cooler, which has an air cooler coil inside. The air cooler coil is connected to the return air fins. The air cooler coil inlet is connected to the refrigerant exhaust main pipe through a refrigerant exhaust branch pipe. The refrigerant exhaust main pipe is connected to an oil separator, and the oil separator is connected to a compressor. The hot water defrosting system for the air cooler includes an air cooler, a defrosting water heat exchanger, a first heat recovery water pump, a defrosting water tank, and a defrosting water pump. The defrosting water heat exchanger is connected to the refrigerant exhaust branch pipe and the refrigerant exhaust main pipe. The first heat recovery water pump is connected between the defrosting water heat exchanger and the defrosting water tank. The defrosting water heat exchanger is also connected to the air cooler. The defrosting water pump is connected between the air cooler and the defrosting water tank. The floor heating system includes a floor heating heat exchanger, a second heat recovery water pump, an ethylene glycol supply and collection device, an ethylene glycol return and collection device, and floor heating pipes. The floor heating heat exchanger is connected to a fluorine exhaust branch pipe and a fluorine exhaust main pipe. The inlet of the floor heating pipe is connected to the outlet of the ethylene glycol supply and collection device, and the outlet of the floor heating pipe is connected to the inlet of the ethylene glycol return and collection device. The inlet of the ethylene glycol supply and collection device is connected to the ethylene glycol inlet main pipe. The outlet of the ethylene glycol return and collection device is connected to the floor heating heat exchanger via a return water main pipe. The ethylene glycol inlet main pipe is connected to the second heat recovery water pump via an ethylene glycol inlet branch pipe. The second heat recovery water pump is also connected to the floor heating heat exchanger, and the floor heating heat exchanger is also connected to the inlet of the ethylene glycol supply and collection device.

[0007] Preferably, the hot water defrosting system for the air cooler further includes a first temperature sensor for detecting the water temperature in the defrosting water tank. The first temperature sensor is connected to a controller, and the controller is also connected to a first heat recovery water pump and a defrosting water pump.

[0008] Preferably, both the defrosting water heat exchanger and the floor heating heat exchanger are plate heat exchangers.

[0009] Preferably, the floor heating system further includes a second temperature sensor for detecting the temperature of the ethylene glycol solution in the ethylene glycol inlet pipe. The second temperature sensor is connected to a controller, which is also connected to a second heat recovery water pump.

[0010] Preferably, the floor heating system further includes a constant pressure water supply unit, which includes an ethylene glycol water supply tank, a water supply pump, and a pressure stabilizing tank. The constant pressure water supply unit is used to automatically supply water to the floor heating heat exchanger according to the pipeline differential pressure.

[0011] Preferably, the constant pressure water supply unit is installed on the return water pipeline of the floor heating system, the water supply pump is installed inside or below the ethylene glycol water supply tank, the outlet of the ethylene glycol water supply tank and the inlet of the water supply pump are connected by a water pipe, and a check valve is provided on the connecting pipeline; a pressure sensor is installed at the outlet of the water supply pump, and the outlet of the water supply pump is connected to the floor heating heat exchanger through a pipeline.

[0012] Preferably, in the hot fluorine defrosting system, a first shut-off valve, a filter, a first solenoid valve, and a second shut-off valve are sequentially installed on the fluorine exhaust branch pipe between the oil separator and the air cooler.

[0013] Preferably, a third temperature sensor and a first pressure sensor are also installed on the refrigerant exhaust branch pipe near the side of the air cooler. The third temperature sensor is connected to the second solenoid valve on the refrigerant supply pipe, and the first pressure sensor is connected to the differential pressure control valve on the refrigerant supply pipe.

[0014] Preferably, the air cooler is also connected to an outdoor pipe well via a defrosting drain pipe, and the air cooler's water tray is also connected to a defrosting water tank.

[0015] Preferably, the defrosting water heat exchanger is used to heat the defrosting water to above 15°C, and the floor heating heat exchanger is used to heat the ethylene glycol solution to above 15°C.

[0016] In summary, by adopting the above technical solution, this utility model has at least the following beneficial effects: By setting up a hot refrigerant defrosting system for evaporative air coolers, a hot water defrosting system for evaporative air coolers, and a floor heating system, the waste heat generated by the refrigeration system can be utilized in multiple scenarios, improving energy conservation and emission reduction effects, and significantly reducing the procurement costs of heating equipment and auxiliary equipment; setting up a floor heating system can eliminate the need for basement or elevated floor design, reducing structural costs.

[0017] The waste heat recovery system of this utility model can complete the heat transfer by using pipe branches and heat exchangers, thereby recovering and reusing the waste heat generated by the refrigeration system. The waste heat recovery system has a simple structure, stable operation, and saves other auxiliary equipment (such as electric heating equipment, centrifugal fans, etc.), reducing the amount of engineering work and lowering safety hazards. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the waste heat recovery system of a large cold storage refrigeration system according to an exemplary embodiment of this utility model.

[0019] Figure 2 This is a schematic diagram of the valve and sensor connections on the fluorine exhaust branch pipe connecting the air cooler and the oil separator in the hot fluorine defrosting system of the air cooler.

[0020] The diagram shows the following components: 1-Air cooler, 2-Freon exhaust manifold, 3-Refrigerant supply pipe, 4-First shut-off valve, 5-Filter valve, 6-First solenoid valve, 7-Second shut-off valve, 8-Third temperature sensor, 9-First pressure sensor, 10-Second solenoid valve, and 11-Differential pressure control valve. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, so that the purpose, technical solution and advantages of the present invention will be clearer. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] The waste heat recovery system of the large-scale cold storage refrigeration system of this utility model, as an exemplary embodiment, mainly includes: a hot refrigerant defrosting system for air coolers, a hot water defrosting system for air coolers, and a floor heating system. The hot refrigerant defrosting system for evaporative air coolers mainly includes an evaporative air cooler, which contains an evaporative air cooler coil. The evaporative air cooler coil is connected to the return air fins. The inlet of the evaporative air cooler coil is connected to the main refrigerant exhaust pipe via a refrigerant exhaust branch pipe. The main refrigerant exhaust pipe is connected to an oil separator, and the oil separator is connected to the compressor (see reference). Figure 1 (The dashed lines in the diagram can represent connection lines between devices or signal transmission lines.) The hot water defrosting system for evaporative air coolers includes an evaporative air cooler, a defrosting water heat exchanger, a first heat recovery water pump, a defrosting water tank, and a defrosting water pump. The defrosting water heat exchanger is connected to the refrigerant exhaust branch pipe and the refrigerant exhaust main pipe. The first heat recovery water pump is connected between the defrosting water heat exchanger and the defrosting water tank. The defrosting water heat exchanger is also connected to the evaporative air cooler. The defrosting water pump is connected between the evaporative air cooler and the defrosting water tank. The floor heating system includes a floor heating heat exchanger, a second heat recovery water pump, an ethylene glycol supply and collection system, an ethylene glycol return and collection system, and floor heating pipes. The floor heating heat exchanger is connected to the fluorine exhaust branch pipe and the fluorine exhaust main pipe. The inlet of the floor heating pipe is connected to the outlet of the ethylene glycol supply and collection system, and the outlet of the floor heating pipe is connected to the inlet of the ethylene glycol return and collection system. The inlet of the ethylene glycol supply and collection system is connected to the ethylene glycol inlet main pipe. The outlet of the ethylene glycol return and collection system is connected to the floor heating heat exchanger via the return water main pipe. The ethylene glycol inlet main pipe is connected to the second heat recovery water pump via an ethylene glycol inlet branch pipe. The second heat recovery water pump is also connected to the floor heating heat exchanger, and the floor heating heat exchanger is also connected to the inlet of the ethylene glycol supply and collection system.

[0023] The working process of the hot fluorine defrosting system for evaporative air coolers mainly includes: the waste fluorine gas (temperature of about 60°C) passes through the oil separator and then enters the evaporative air cooler coil through the fluorine exhaust branch pipe from the inlet of the evaporative air cooler coil and flows inside it, using the heat of the waste fluorine gas to melt the frost layer on the return air vent fins.

[0024] The working process of the hot water defrosting system for evaporative air coolers mainly includes: when hot water defrosting is required, waste heat from fluorine enters the defrosting water heat exchanger through the fluorine exhaust branch pipe. When the water temperature in the defrosting water tank is lower than the preset temperature, the cold water in the defrosting water tank is transported to the defrosting water heat exchanger for heating by the first heat recovery water pump. After being heated to the preset temperature, the water enters the evaporative air cooler through the outlet of the defrosting water heat exchanger to defrost the evaporative air cooler coil (defrosting can be performed inside the evaporative air cooler coil or directly on the surface of the evaporative air cooler coil without entering the evaporative air cooler coil); when the water temperature in the defrosting water tank is higher than the preset temperature, the first heat recovery water pump stops working, and the defrosting water pump starts to transport the water in the defrosting water tank into the evaporative air cooler to perform hot water defrosting on the evaporative air cooler coil.

[0025] The working process of the floor heating system mainly includes: ethylene glycol solution enters the floor heating pipe through the ethylene glycol supply main pipe and ethylene glycol water collector to prevent the floor from freezing; when the temperature of the ethylene glycol solution is lower than the preset temperature, the ethylene glycol solution stops entering the ethylene glycol water collector, and the second heat recovery water pump starts to transport the ethylene glycol solution to the floor heating heat exchanger. Fluorine waste heat gas enters the floor heating heat exchanger through the fluorine exhaust branch pipe to heat the ethylene glycol solution. The heated ethylene glycol solution enters the floor heating pipe through the ethylene glycol water collector to circulate and heat the floor, preventing the floor from freezing due to low temperature. The ethylene glycol solution enters the ethylene glycol return water collector through the outlet of the floor heating pipe and returns to the floor heating heat exchanger for heating.

[0026] In buildings without basements or raised floors, there is a significant temperature difference between the interior floor of a cold storage facility and the soil subbase beneath the insulation layer (e.g., -20°C in the storage area and +20°C in the soil). Even with insulation installed on the floor, the low temperature can still penetrate the insulation and seep into the soil subbase over time. This temperature difference can cause the soil to freeze, leading to soil freezing. Once frozen, the soil expands, causing frost heave and cracking of the cold storage floor, affecting its normal operation. Installing floor heating pipes to prevent soil freezing ensures the long-term stable operation of the cold storage.

[0027] Furthermore, the hot water defrosting system for the evaporative air cooler also includes a first temperature sensor for detecting the water temperature in the defrosting water tank. The first temperature sensor is connected to a controller, which is also connected to a first heat recovery water pump and a defrosting water pump. When the first temperature sensor detects that the water temperature in the defrosting water tank is lower than a preset temperature (10°C), it sends a signal to the controller. After receiving the signal, the controller sends control signals to the first heat recovery water pump and the defrosting water pump to shut down the defrosting water pump and start the first heat recovery water pump to transport the water in the defrosting water tank to the defrosting water heat exchanger for heat exchange. After the water temperature rises to the defrosting temperature (not less than 15°C), it enters the evaporative air cooler to defrost the evaporative air cooler coils. When the water temperature in the defrosting water tank is higher than the preset temperature, the first temperature sensor sends a signal to the controller, which then sends control signals to the first heat recovery water pump and the defrosting water pump to shut down the first heat recovery water pump and start the defrosting water pump to defrost the evaporative air cooler coils with hot water. When it is time to end the defrosting process, the controller controls the first heat recovery water pump and / or the defrosting water pump to shut down to end the defrosting process.

[0028] Furthermore, both the defrosting water heat exchanger and the floor heating heat exchanger employ plate heat exchangers. Plate heat exchangers are assembled from multiple alternating plates. One adjacent plate carries the liquid to be heated, while another carries the waste heat gas from the fluorine system. Heat is transferred from the waste heat gas to the liquid to be heated, thus achieving the heat exchange process. Compared to other heat exchangers (such as shell-and-tube heat exchangers), plate heat exchangers are compact, occupy a small area, are easy to maintain, and are highly adaptable. The closely spaced plates and narrow, parallel fluid channels result in a high heat transfer coefficient, improving heat transfer efficiency. In practical applications, the heat exchange area or flow combination can be easily changed, offering high flexibility.

[0029] The defrosting water heat exchanger can also be directly connected to the defrosting water tank via connecting pipes. The water heated by the defrosting water heat exchanger can return to the defrosting water tank. When the water in the defrosting water tank reaches the defrosting temperature, the first heat recovery water pump stops working, and the defrosting water pump introduces the water from the defrosting water tank into the air cooler for hot water defrosting.

[0030] When selecting a defrost water heat exchanger, assume the defrost water tank circulation volume... Fluorine waste heat gas exhaust temperature on the hot side inlet water water outlet temperature Mass heat capacity of water ,according to The heat exchange was calculated. Therefore, it can be concluded that a plate heat exchanger with a heat exchange capacity of 400kW should be selected for the defrosting water heat exchanger.

[0031] The floor heating system also includes a second temperature sensor for detecting the temperature of the ethylene glycol solution in the ethylene glycol inlet main pipe. The second temperature sensor is connected to the controller, which is also connected to the second heat recovery water pump. When the second temperature sensor detects that the temperature of the ethylene glycol solution in the ethylene glycol inlet main pipe is lower than the preset temperature (5°C), it sends a signal to the controller. After receiving the signal, the controller sends a control signal to the second heat recovery water pump to start the pump and deliver the ethylene glycol solution in the ethylene glycol solution supply main pipe to the floor heating heat exchanger. At the same time, the fluorine waste heat gas enters the floor heating heat exchanger through the fluorine exhaust branch pipe to heat the ethylene glycol solution, raising its temperature to the floor heating temperature (not less than 15°C).

[0032] When selecting a floor heating heat exchanger, the rated power of the heat exchanger is determined based on the floor heating area. For example, when two buildings share a floor heating system, one or more plate heat exchangers with a rated power of 300kW are configured. When a building uses a separate floor heating system, a plate heat exchanger with a rated power of 50kW is configured for that building.

[0033] The floor heating system also includes a constant pressure water supply unit, which mainly consists of an ethylene glycol water supply tank (1 m³), ​​a water supply pump, and a pressure stabilizing tank. It can automatically supply water to the floor heating heat exchanger based on the differential pressure in the pipeline. The constant pressure water supply unit is installed on the return water pipeline of the floor heating system to ensure effective water supply. The water supply pump is installed inside or below the ethylene glycol water supply tank to ensure water intake. The outlet of the ethylene glycol water supply tank and the inlet of the water supply pump are connected by a water pipe, and a check valve is installed on the connecting pipe to ensure that the ethylene glycol solution can only flow from the ethylene glycol water supply tank to the water supply pump. A second pressure sensor is installed at the outlet of the water supply pump, and the outlet of the water supply pump is connected to the floor heating heat exchanger via a pipeline.

[0034] Furthermore, in the hot refrigerant defrosting system, a first shut-off valve 4, a filter 5, a first solenoid valve 6, and a second shut-off valve 7 are sequentially installed on the refrigerant exhaust branch pipe 2 between the oil separator and the air cooler 1 (see reference). Figure 2 To regulate the pressure and flow rate of the waste heat gas from fluorine, and improve the hot fluorine defrosting effect; a third temperature sensor 8 and a first pressure sensor 9 are also installed on the fluorine exhaust branch pipe 2 near the side of the air cooler 1. The third temperature sensor 8 is connected to the second solenoid valve 10 on the refrigerant supply pipe 3, and the first pressure sensor 9 is connected to the differential pressure control valve 11 on the refrigerant supply pipe 3, so as to automatically control the flow of refrigerant medium and ensure that the air cooler stops during hot fluorine defrosting and no refrigerant enters the air cooler.

[0035] The evaporative cooler is also connected to the outdoor manhole via a defrosting drain pipe (see reference). Figure 1In the hot refrigerant defrosting process of the evaporative air cooler, after the frost on the fins at the return air vent of the evaporative air cooler is defrosted, it is discharged to the outdoor pipe well through the defrosting drain pipe. The evaporative air cooler's water tray is also connected to the defrosting water tank. After the evaporative air cooler is defrosted with hot water, the defrosting water flows back to the defrosting water tank.

[0036] During the defrosting process of the evaporative air cooler, the waste heat gas from the refrigerant can be controlled to enter different refrigerant exhaust branches according to the defrosting requirements of the evaporative air cooler. The hot refrigerant defrosting system and / or hot water defrosting system of the evaporative air cooler can be used to defrost the evaporative air cooler, thereby improving the defrosting efficiency of the evaporative air cooler.

[0037] In the hot refrigerant defrosting system, hot water defrosting system, and floor heating system, the waste refrigerant gas passes through the evaporator coil, defrosting water heat exchanger, and floor heating heat exchanger, respectively, and can then return to the compressor through a separate refrigerant exhaust branch pipe (not shown in the figure), so that the refrigerant can be recycled and its utilization rate can be improved.

[0038] The waste heat recovery system of this invention can effectively improve the working efficiency of a large cold storage refrigeration system and significantly improve energy saving. Taking a low-temperature cold storage refrigeration system with a cold storage area of ​​2890 square meters as an example, this cold storage is equipped with 6 air coolers. There is no power consumption during the defrosting process of the air coolers, and the energy consumed during the defrosting process is negligible. Calculated based on 3 defrostings per day and a total heating time of 1 hour, compared with the electric defrosting method (total defrosting power of 248 kW, daily defrosting power consumption of 248 kWh), the thermal defrosting method can reduce power consumption by 248 kWh per day. Traditional floor antifreeze methods usually use mechanical ventilation, which typically requires a 20 kW centrifugal fan to run 24 hours a day, consuming 480 kW of electricity per day. h, while using a floor heating system for floor antifreeze only requires adding a 3kW circulating pump, which consumes 72kW of electricity per day (24 hours). h, which can reduce power consumption by 408kW compared to mechanical ventilation. h; Waste heat recovery can also reduce the condensing load by 15%, significantly improving the operating efficiency of the evaporative condenser. Due to the reduced condensing load, the evaporative condenser can reduce power consumption by at least 5kW, which translates to a direct reduction of 120kW per day (24 hours). h. Assuming the refrigeration system's main unit operates at an average rate of 45%, waste heat recovery can save 248kW of electricity annually. h+408kW h+120kW h) * 365 days * 45% average operating rate of main unit = 127458kW h has considerable economic value.

[0039] The above description is merely a detailed illustration of specific embodiments of this utility model, and not a limitation thereof. Various substitutions, modifications, and improvements made by those skilled in the art without departing from the principles and scope of this utility model should be included within the protection scope of this utility model.

Claims

1. A waste heat recovery system for a large scale cold storage refrigeration system, characterized by, This includes a hot refrigerant defrosting system for evaporative air coolers, a hot water defrosting system for evaporative air coolers, and a floor heating system. The hot refrigerant defrosting system for the air cooler includes an air cooler, which has an air cooler coil inside. The air cooler coil is connected to the return air fins. The air cooler coil inlet is connected to the refrigerant exhaust main pipe through a refrigerant exhaust branch pipe. The refrigerant exhaust main pipe is connected to an oil separator, and the oil separator is connected to a compressor. The hot water defrosting system for the air cooler includes an air cooler, a defrosting water heat exchanger, a first heat recovery water pump, a defrosting water tank, and a defrosting water pump. The defrosting water heat exchanger is connected to the refrigerant exhaust branch pipe and the refrigerant exhaust main pipe. The first heat recovery water pump is connected between the defrosting water heat exchanger and the defrosting water tank. The defrosting water heat exchanger is also connected to the air cooler. The defrosting water pump is connected between the air cooler and the defrosting water tank. The floor heating system includes a floor heating heat exchanger, a second heat recovery water pump, an ethylene glycol supply and collection device, an ethylene glycol return and collection device, and floor heating pipes. The floor heating heat exchanger is connected to a fluorine exhaust branch pipe and a fluorine exhaust main pipe. The inlet of the floor heating pipe is connected to the outlet of the ethylene glycol supply and collection device, and the outlet of the floor heating pipe is connected to the inlet of the ethylene glycol return and collection device. The inlet of the ethylene glycol supply and collection device is connected to the ethylene glycol inlet main pipe. The outlet of the ethylene glycol return and collection device is connected to the floor heating heat exchanger via a return water main pipe. The ethylene glycol inlet main pipe is connected to the second heat recovery water pump via an ethylene glycol inlet branch pipe. The second heat recovery water pump is also connected to the floor heating heat exchanger, and the floor heating heat exchanger is also connected to the inlet of the ethylene glycol supply and collection device.

2. The waste heat recovery system of a large scale cold storage plant refrigeration system as claimed in claim 1 wherein, The hot water defrosting system for the air cooler also includes a first temperature sensor for detecting the water temperature in the defrosting water tank. The first temperature sensor is connected to a controller, which is also connected to a first heat recovery water pump and a defrosting water pump.

3. The waste heat recovery system of a large scale cold storage plant refrigeration system as claimed in claim 1 wherein, Both the defrosting water heat exchanger and the floor heating heat exchanger are plate heat exchangers.

4. The waste heat recovery system of a large scale cold storage plant refrigeration system according to claim 1, characterized in that, The floor heating system also includes a second temperature sensor for detecting the temperature of the ethylene glycol solution in the ethylene glycol inlet pipe. The second temperature sensor is connected to the controller, which is also connected to the second heat recovery water pump.

5. The waste heat recovery system of a large scale cold storage plant refrigeration system as claimed in claim 1 wherein, The floor heating system also includes a constant pressure water supply unit, which includes an ethylene glycol water supply tank, a water supply pump, and a pressure stabilizing tank. The constant pressure water supply unit is used to automatically supply water to the floor heating heat exchanger according to the differential pressure of the pipeline.

6. The waste heat recovery system of a large scale cold storage plant refrigeration system according to claim 5, characterized in that, The constant pressure water supply unit is installed on the return water pipeline of the floor heating system. The water supply pump is installed inside or below the ethylene glycol water supply tank. The outlet of the ethylene glycol water supply tank and the inlet of the water supply pump are connected by a water pipe, and a check valve is installed on the connecting pipeline. A pressure sensor is installed at the outlet of the water supply pump, and the outlet of the water supply pump is connected to the floor heating heat exchanger through a pipeline.

7. The waste heat recovery system of a large scale cold storage plant refrigeration system as claimed in claim 1 wherein, In the hot fluorine defrosting system, a first shut-off valve, a filter, a first solenoid valve, and a second shut-off valve are sequentially installed on the fluorine exhaust branch pipe between the oil separator and the air cooler.

8. The waste heat recovery system of a large scale cold storage plant refrigeration system as claimed in claim 7, wherein, A third temperature sensor and a first pressure sensor are also installed on the refrigerant exhaust branch pipe near the side of the air cooler. The third temperature sensor is connected to the second solenoid valve on the refrigerant supply pipe, and the first pressure sensor is connected to the differential pressure control valve on the refrigerant supply pipe.

9. The waste heat recovery system of a large scale cold storage plant refrigeration system as claimed in claim 1 wherein, The air cooler is also connected to an outdoor pipe well via a defrosting drain pipe, and the air cooler's water tray is also connected to a defrosting water tank.

10. The waste heat recovery system of a large scale cold storage plant refrigeration system according to any one of claims 1 to 9, characterized in that, The defrosting water heat exchanger is used to heat the defrosting water to above 15°C, and the floor heating heat exchanger is used to heat the ethylene glycol solution to above 15°C.

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