Composite evaporative cooling type heat pump unit

Abstract

The invention discloses a composite evaporative cooling type heat pump unit which comprises an air cooling fan and an evaporative air cooler which are located at the top of the unit, functional areas of a box body of the unit are distinguished through double-layer grids, the grid on the left side corresponds to an air inlet, the grid in the middle covers filler for evaporative cooling, and a water tank for collecting spray water is arranged at the bottom. A cooling water pump for pushing water circulation is arranged on the side of the water tank; the unit is provided with an evaporative heat exchanger, an air-cooled heat exchanger, a shell and tube evaporator, a compressor, a gas-liquid separator and an oil separator, the evaporative heat exchanger is connected with the air-cooled heat exchanger through a liquid pipe, each template is provided with an independent cut-off ball valve, and a main loop is directly connected with a four-way valve and an electromagnetic valve automatic switching loop; an EVD data collector is arranged at an outlet of the shell and tube evaporator and is directly connected with the four-way valve, and an electromagnetic valve automatic switching loop is connected to an inlet through a copper pipe; the compressor and the four-way valve are adjacently arranged on the lower side of the box body, one end of the gas-liquid separator is connected with an exhaust port of the compressor through a steel pipe, and the other end is connected with the four-way valve; one end of the oil separator is connected with an exhaust port of the compressor through a steel pipe, and the other end is connected with the four-way valve. The problem that an evaporative heat pump unit in a low-temperature environment area in winter is unstable in heating effect is solved, meanwhile, the refrigerating efficiency is higher than that of an air-cooled heat pump, system operation is stable, and energy conservation and emission reduction are achieved.

Description

Technical Field

[0001] This invention relates to the field of hot and cold water production equipment, and more particularly to a composite evaporative cooling heat pump unit. Background Technology

[0002] Vapor compression heat pumps transfer heat energy based on the heat absorption and release characteristics of low-boiling-point refrigerants during phase change. The unit operates through a closed-loop system, with four core components working collaboratively: a compressor, condenser, throttling device, and evaporator. The evaporator absorbs heat from a low-temperature heat source, causing the liquid refrigerant to evaporate into a low-temperature, low-pressure gas. The compressor compresses this low-temperature gas into a high-temperature, high-pressure gas. The high-temperature gas enters the condenser, releasing sensible and latent heat to the high-temperature environment and condensing into a high-pressure liquid. The high-pressure liquid refrigerant, after being depressurized by the throttling device, forms a low-temperature, low-pressure gas-liquid two-phase flow and re-enters the evaporator to absorb heat. The refrigeration cycle follows a continuous process of "evaporation heat absorption - compression pressure increase - condensation heat release - throttling pressure reduction," achieving a reverse heat transfer from a low-temperature environment to a high-temperature environment. The system uses a four-way valve to switch the refrigerant flow direction, allowing for flexible switching of operating modes and integrated operation in both heating and cooling modes.

[0003] Existing technology, such as an evaporative heat pump unit (application number 2020110036715), includes a compressor, a first four-way valve, a second four-way valve, an evaporative condenser, a first electric valve, a second electric valve, a third electric valve, a solenoid valve, a first throttling valve, a second throttling valve, a third throttling valve, an air conditioning water-side heat exchanger, a first finned heat exchanger, a second finned heat exchanger, and a gas-liquid separator connected in the refrigeration cycle loop. In the present invention, when in cooling mode, the high-temperature and high-pressure gas discharged from the compressor enters the evaporative condenser, releases heat to the outdoor air and circulating water, and condenses into a high-pressure liquid. Then, it is throttled by the throttling valve into a low-temperature and low-pressure gas-liquid mixture refrigerant. After that, it absorbs heat from the air conditioning chilled water in the air conditioning water-side heat exchanger to cool it down and evaporate it into a low-pressure gas. Then, it returns directly to the compressor via the electric valve.

[0004] However, in winter, existing evaporative heat pumps, when operating for heating, use an evaporative condenser that absorbs heat. The contact between the low-temperature, humid air and the cold surface poses a risk of the spray water freezing and the finned tubes becoming blocked with ice, potentially leading to system energy efficiency failure and mechanical damage. Traditional antifreeze solutions rely on chemical agents or passive switching, which suffer from ecological hazards, energy efficiency loss, and control lag. Therefore, in regions with low winter temperatures, the heating function of evaporative heat pump units cannot operate stably. While air-cooled heat pumps can heat normally in winter, the condensing temperature rises with the increase in summer ambient temperature, significantly reducing cooling effect and efficiency, and posing risks of high-pressure alarms and system shutdown, failing to meet the current demand for energy-efficient products.

[0005] Therefore, it is necessary to develop new types of composite evaporative cooling heat pump units to overcome the above problems. Summary of the Invention

[0006] Purpose of the invention: In view of the shortcomings and defects of the existing technology, the present invention provides a composite evaporative cooling heat pump unit, which solves the problem of unstable heating effect of evaporative heat pump units in low-temperature environments in winter. At the same time, the cooling efficiency is higher than that of air-cooled heat pumps, the system operates stably, and it saves energy and reduces emissions.

[0007] Technical Solution: This invention provides a composite evaporative cooling heat pump unit, characterized in that it includes an air-cooled fan and an evaporative air cooler located at the top of the unit; the unit's casing is divided into functional areas by a double-layer grille, with the left grille corresponding to the air inlet, the middle grille covered with packing material for evaporative cooling, and a water tank at the bottom for collecting sprayed water; a cooling water pump for driving water circulation is installed on the side of the water tank; the unit is equipped with an evaporative heat exchanger, an air-cooled heat exchanger, a shell-and-tube evaporator, a compressor, a gas-liquid separator, and an oil separator; the evaporative heat exchanger and the air-cooled heat exchanger are connected by a liquid... The pipe connection is as follows: each template is equipped with an independent shut-off ball valve, and the main circuit is directly connected to the four-way valve and the solenoid valve automatic switching circuit; the shell-and-tube evaporator is equipped with an EVD data acquisition device at the outlet, which is directly connected to the four-way valve, and the inlet is connected to the solenoid valve automatic switching circuit with a copper pipe; the compressor and the four-way valve are arranged adjacent to each other on the lower side of the housing, one end of the gas-liquid separator is connected to the compressor's exhaust port through a steel pipe, and the other end is connected to the four-way valve; one end of the oil separator is connected to the compressor's exhaust port through a steel pipe, and a copper pipe is set at the bottom to connect to the compressor's oil return port, and the other end is connected to the four-way valve.

[0008] The unit's casing is equipped with a water supply inlet, a drainage outlet, a sewage outlet, and an overflow outlet for the water system.

[0009] The unit is equipped with an outer protective plate on its top, which covers the unit.

[0010] The unit's casing is equipped with an air inlet plate.

[0011] The side-mounted air intake panel optimizes airflow organization.

[0012] The unit is equipped with a high-pressure liquid storage tank.

[0013] The unit's enclosure is equipped with an electrical control cabinet, which is independently and isolatedly located in the middle right part of the unit's enclosure.

[0014] The method of using the composite evaporative cooling heat pump unit of the present invention is characterized in that: in the cooling mode, solenoid valves #2 and #4 are opened, and solenoid valves #1 and #3 are closed. The high-temperature refrigerant discharged from the compressor first flows through the copper tube aluminum fin heat exchanger for primary heat exchange, and the condensed heat is carried away by the fan-driven air. After the refrigerant comes out of the fin heat exchanger, it passes through the evaporative cooling heat exchanger for secondary enhanced heat exchange. The cooling water pump sends cooling water to the water distributor at the top of the evaporative cooling heat exchanger and sprays it evenly on the evaporative cooling heat exchanger to form a water film. The fan drives the air to discharge the latent heat of vaporization of the water to the atmosphere, further enhancing the condensation heat exchange. The condensed liquid refrigerant flows through the liquid storage tank and the drying filter cartridge, and is throttled and depressurized by the electronic expansion valve. It evaporates and absorbs heat in the shell and tube heat exchanger. Finally, the refrigerant vapor is drawn into the compressor from the evaporator and compressed into high-pressure vapor. This cycle is repeated to complete the cycle. During this process, the refrigerant continuously absorbs heat from the room and releases it into the environment, thereby achieving the cooling effect.

[0015] In heating mode, solenoid valves #1 and #3 are open, while solenoid valves #2 and #4 are closed. The high-temperature refrigerant discharged from the compressor first flows through the shell-and-tube heat exchanger, releasing sensible and latent heat to the indoor circulating water, condensing into a high-pressure liquid, and simultaneously raising the water temperature for heating. After the high-pressure liquid refrigerant is throttled and depressurized by the electronic expansion valve, it forms a low-temperature, low-pressure gas-liquid two-phase flow and enters the outdoor finned heat exchanger. In the evaporator, the refrigerant absorbs heat from the outdoor air and completely evaporates into a gas. This process is driven by a fan to force air convection, enhancing the heat exchange efficiency between the gaseous refrigerant and the air. The low-temperature refrigerant vapor after absorbing heat returns to the compressor to complete the cycle. The system dynamically adjusts the opening of the expansion valve through a thermal PID algorithm to maintain the superheat at the evaporator outlet and ensure the compressor operates in dry compression mode. Throughout the entire heating cycle, the refrigerant continuously extracts heat from the low-temperature outdoor air and transfers it to the indoor environment, achieving the heating effect.

[0016] The unit uses an air intake grille to allow natural convection with the outside environment, carrying away the heat generated during system operation.

[0017] Beneficial Effects: Compared with existing technologies, this invention has the following significant advantages: This invention solves the problem of unstable heating effect of evaporative heat pump units in low-temperature environments during winter, while having higher cooling efficiency than air-cooled heat pumps, stable system operation, and energy saving and emission reduction. 1) High Efficiency and Energy Saving: The unit adopts a "two-stage condensation" technology combining air cooling and evaporative cooling, utilizing external cold air for heat exchange, thereby reducing the condensation temperature of the system and significantly reducing energy consumption. 2) Environmentally Friendly: A closed-loop circulation system design is adopted, with a water collector at the air outlet providing excellent water collection, and a splash-proof air inlet grille at the water inlet to minimize drift loss during cooling tower operation, achieving internal water recycling and significantly reducing wastewater discharge. This is of great significance for water resource protection and reducing water pollution. 3) Wide Operating Range: The unit's maximum cooling ambient temperature can reach 55℃, and the minimum heating ambient temperature can reach -10℃. By adjusting the operating mode and control parameters, it can adapt to various complex and changing operating environments, ensuring stable operation and efficient cooling effect. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention;

[0019] Figure 2 This is a system diagram of the present invention;

[0020] In the diagram, 1 is an air-cooled fan; 2 is an evaporative air cooler; 3 is an outer protective plate; 4 is packing material; 5 is a water tank; 6 is a liquid pipe; 7 is a cooling water pump; 8 is a gas-liquid separator; 9 is a water inlet; 10 is a drain outlet; 11 is a sewage outlet; 12 is an overflow outlet; 13 is a four-way valve; 14 is a compressor; 15 is a shell-and-tube evaporator; 16 is a high-pressure liquid receiver; 17 is an electrical control cabinet; and 18 is an air inlet plate. Detailed Implementation

[0021] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 , 2The composite evaporative cooling heat pump unit of the present invention includes an air-cooled fan 1 and an evaporative cooling fan 2 located at the top of the unit. The unit's casing is divided into functional areas by a double-layer grille. The left grille corresponds to the air inlet, the middle grille is covered with packing 4 for evaporative cooling, and the bottom is a water tank 5 for collecting spray water. A cooling water pump 7 for driving water circulation is installed on the side of the water tank 5. The unit is equipped with an evaporative heat exchanger, an air-cooled heat exchanger, a shell-and-tube evaporator 15, a compressor 14, a gas-liquid separator 8, and an oil separator. The evaporative heat exchanger and the air-cooled heat exchanger are connected by a liquid pipe 6. Each module is equipped with... The unit features an independent shut-off ball valve, with the main circuit directly connected to the four-way valve 13 and the solenoid valve automatic switching circuit. An EVD data acquisition unit is installed at the outlet of the shell-and-tube evaporator 15, directly connected to the four-way valve 13, and a copper pipe connects to the solenoid valve automatic switching circuit at the inlet. The compressor 14 is arranged adjacent to the four-way valve 13 on the lower side of the housing. One end of the gas-liquid separator 8 is connected to the exhaust port of the compressor 14 via a steel pipe, and the other end is connected to the four-way valve 13. One end of the oil separator is connected to the exhaust port of the compressor 14 via a steel pipe, and a copper pipe at the bottom connects to the oil return port of the compressor 14; the other end is connected to the four-way valve 13. The unit's housing includes a water supply inlet 9, a drain outlet 10, a wastewater outlet 11, and an overflow outlet 12. An outer protective plate 3 covers the top of the unit. The housing also includes an air inlet plate 18, which is laterally mounted to optimize airflow. The unit is equipped with a high-pressure liquid receiver 16. The unit's enclosure is equipped with an electrical control cabinet 17, which is independently and isolatedly located in the middle right part of the unit's enclosure.

[0023] The method of using the composite evaporative cooling heat pump unit of the present invention is as follows: In cooling mode, solenoid valves #2 and #4 are opened, and solenoid valves #1 and #3 are closed. The high-temperature refrigerant discharged from the compressor first flows through the copper tube aluminum fin heat exchanger for primary heat exchange. The condensed heat is carried away by air driven by a fan. After the refrigerant comes out of the fin heat exchanger, it passes through the evaporative cooling heat exchanger for secondary enhanced heat exchange. The cooling water pump sends cooling water to the water distributor at the top of the evaporative cooling heat exchanger and sprays it evenly on the evaporative cooling heat exchanger to form a water film. The fan drives the air to discharge the latent heat of vaporization of the water evaporation into the atmosphere, further enhancing the condensation heat exchange. The condensed liquid refrigerant flows through the liquid storage tank and the drying filter cartridge, and is throttled and depressurized by the electronic expansion valve. It evaporates and absorbs heat in the shell and tube heat exchanger. Finally, the refrigerant vapor is drawn into the compressor from the evaporator and compressed into high-pressure vapor. This cycle is repeated to complete the cycle. During this process, the refrigerant continuously absorbs heat from the room and releases it into the environment, thereby achieving the cooling effect.

[0024] In heating mode, solenoid valves #1 and #3 are open, while solenoid valves #2 and #4 are closed. The high-temperature refrigerant discharged from the compressor first flows through the shell-and-tube heat exchanger, releasing sensible and latent heat to the indoor circulating water, condensing into a high-pressure liquid, and simultaneously raising the water temperature for heating. After the high-pressure liquid refrigerant is throttled and depressurized by the electronic expansion valve, it forms a low-temperature, low-pressure gas-liquid two-phase flow and enters the outdoor finned heat exchanger. In the evaporator, the refrigerant absorbs heat from the outdoor air and completely evaporates into a gas. This process is driven by a fan to force air convection, enhancing the heat exchange efficiency between the gaseous refrigerant and the air. The low-temperature refrigerant vapor after absorbing heat returns to the compressor to complete the cycle. The system dynamically adjusts the opening of the expansion valve through a thermal PID algorithm to maintain the superheat at the evaporator outlet and ensure the compressor operates in dry compression mode. Throughout the entire heating cycle, the refrigerant continuously extracts heat from the low-temperature outdoor air and transfers it to the indoor environment, achieving the heating effect.

[0025] The unit uses air intake grilles to allow natural convection with the outside environment, carrying away the heat generated during system operation.

[0026] This invention combines air cooling and evaporative cooling to form a highly efficient "two-stage condensation" technology. The unit is encased in an outer shroud and, through a compact, layered layout and modular piping integration, achieves efficient synergy between evaporative cooling and air cooling, making it suitable for the energy supply needs of buildings in high-humidity, high-temperature, and extremely cold regions.

[0027] This invention solves the problem of unstable heating performance of evaporative heat pump units in low-temperature winter environments. Simultaneously, it boasts higher cooling efficiency than air-cooled heat pumps, stable system operation, and energy savings and emission reduction. The invention features: 1) High efficiency and energy saving: The unit employs a "two-stage condensation" technology combining air cooling and evaporative cooling, utilizing external cold air for heat exchange, thereby reducing the system's condensing temperature and significantly lowering energy consumption. 2) Environmental friendliness: A closed-loop circulation system design is adopted, using a high-efficiency water collector at the air outlet and a splash-proof air inlet grille to minimize drift loss during cooling tower operation, achieving internal water recycling and significantly reducing wastewater discharge. This is of great significance for water resource protection and reducing water pollution. 3) Wide operating range: The unit's maximum cooling ambient temperature can reach 55℃, and the minimum heating ambient temperature can reach -10℃. By adjusting the operating mode and control parameters, it can adapt to various complex and changing operating environments, ensuring stable operation and efficient cooling.

Claims

1. A composite evaporative cooling heat pump unit, characterized in that: The unit includes an air-cooled fan (1) and an evaporative air cooler (2) located at the top of the unit. The unit's casing is divided into functional areas by a double-layer grille. The grille on the left corresponds to the air inlet, and the grille in the middle is covered with packing material (4) for evaporative cooling. The bottom is a water tank (5) for collecting spray water. A cooling water pump (7) for driving water circulation is installed on the side of the water tank (5). The unit is equipped with an evaporative heat exchanger, an air-cooled heat exchanger, a shell-and-tube evaporator (15), a compressor (14), a gas-liquid separator (8), and an oil separator. The evaporative heat exchanger and the air-cooled heat exchanger are connected by a liquid pipe (6). Each module is equipped with an independent shut-off ball valve. The main circuit The four-way valve (13) and the solenoid valve automatic switching circuit are directly connected; the shell-and-tube evaporator (15) is equipped with an EVD data acquisition device at the outlet, which is directly connected to the four-way valve (13), and the inlet is connected to the solenoid valve automatic switching circuit with a copper pipe; the compressor (14) and the four-way valve (13) are arranged adjacent to each other on the lower side of the housing, one end of the gas-liquid separator (8) is connected to the exhaust port of the compressor (14) through a steel pipe, and the other end is connected to the four-way valve (13); one end of the oil separator is connected to the exhaust port of the compressor (14) through a steel pipe, and a copper pipe is set at the bottom to connect to the oil return port of the compressor (14), and the other end is connected to the four-way valve (13).

2. The composite evaporative cooling heat pump unit according to claim 1, characterized in that: The unit's casing is equipped with a water supply inlet (9), a drainage outlet (10), a sewage outlet (11), and an overflow outlet (12) for the water system.

3. The composite evaporative cooling heat pump unit according to claim 1, characterized in that: The unit is equipped with an outer protective plate (3) on top, which covers the unit.

4. The composite evaporative cooling heat pump unit according to claim 1, characterized in that: The unit's casing is equipped with an air inlet plate (18).

5. The composite evaporative cooling heat pump unit according to claim 4, characterized in that: The air inlet plate (18) is installed laterally to optimize airflow organization.

6. The composite evaporative cooling heat pump unit according to claim 1, characterized in that: The unit is equipped with a high-pressure liquid receiver (16).

7. The composite evaporative cooling heat pump unit according to claim 1, characterized in that: The unit's enclosure is equipped with an electrical control cabinet (17), which is independently and isolatedly located in the middle right part of the unit's enclosure.

8. The method of using the composite evaporative cooling heat pump unit according to any one of claims 1-7, characterized in that: In cooling mode, solenoid valves #2 and #4 are open, while solenoid valves #1 and #3 are closed. The high-temperature refrigerant discharged from the compressor first flows through a copper tube aluminum fin heat exchanger for primary heat exchange. The condensed heat is then carried away by air driven by a fan. After exiting the fin heat exchanger, the refrigerant passes through an evaporative cooling heat exchanger for secondary enhanced heat exchange. A cooling water pump delivers cooling water to the water distributor at the top of the evaporative cooling heat exchanger, spraying it evenly onto the heat exchanger to form a water film. The fan drives air to expel the latent heat of vaporization from the water evaporation into the atmosphere, further enhancing condensation heat exchange. The condensed liquid refrigerant flows through a liquid receiver and a dryer filter cartridge, where it is throttled and depressurized by an electronic expansion valve. It then evaporates and absorbs heat in a shell-and-tube heat exchanger. Finally, the refrigerant vapor is drawn into the evaporator by the compressor and compressed into high-pressure vapor. This cycle is repeated continuously to complete the cycle. During this process, the refrigerant continuously absorbs heat from the room and releases it into the environment, thus achieving the cooling effect.

9. The method of using the composite evaporative cooling heat pump unit according to claim 8, characterized in that: In heating mode, solenoid valves #1 and #3 are open, while solenoid valves #2 and #4 are closed. The high-temperature refrigerant discharged from the compressor first flows through the shell-and-tube heat exchanger, releasing sensible and latent heat to the indoor circulating water, condensing into a high-pressure liquid, and simultaneously raising the water temperature for heating. After the high-pressure liquid refrigerant is throttled and depressurized by the electronic expansion valve, it forms a low-temperature, low-pressure gas-liquid two-phase flow and enters the outdoor finned heat exchanger. Inside the evaporator, the refrigerant absorbs heat from the outside air and evaporates completely into a gas. This process is driven by a fan to force air convection, enhancing the heat exchange efficiency between the gaseous refrigerant and the air. The low-temperature refrigerant vapor after absorbing heat and vaporizing returns to the compressor to complete the cycle. The system dynamically adjusts the opening of the expansion valve through a thermal PID algorithm to maintain the superheat at the evaporator outlet and ensure the dry compression operation of the compressor. Throughout the heating cycle, the refrigerant continuously extracts heat from the low-temperature outdoor air and transfers it to the indoor environment to achieve the heating effect.

10. The method of using the composite evaporative cooling heat pump unit according to claim 9, characterized in that: The unit uses an air intake grille to allow natural convection with the outside environment, carrying away the heat generated during system operation.

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