CN1045708C - Aquaculture heat pump - Google Patents

Abstract

An aquaculture heat pump includes an air heat exchanger, a four-way valve, a compressor, a water-cooled condenser, etc., and a dual The expansion valve is a heating or cooling two-way working medium expansion device composed of double one-way valves, liquid storage tanks and filters. It has the multifunctional function of cooling or warming the air, and it can operate normally in the best operating condition within a wide range of ambient temperature changes.

Description

Aquaculture heat pump

The invention relates to a heat pump system for heating or cooling aquaculture water with bidirectional working mode (heating or cooling).

The aquaculture heat pump is a kind of low-temperature and low-pressure working medium that absorbs the heat of the environment in the evaporator and evaporates into a gas. After the temperature and pressure of the compressor are raised, it is condensed into a high-pressure and low-temperature liquid in the condenser, and the heat is released to supply water for aquaculture. , so that the water temperature rises, and then the condensed liquid working medium expands and becomes a low-pressure liquid working medium and returns to the evaporator to evaporate, so that the cycle is repeated, so that the ambient heat and the work consumed by the compressor are continuously converted, and the heat is transferred A system that goes into aquaculture water. This system enters a reverse cycle through a switching mechanism, and can be converted to cooling operation to reduce the water temperature of aquaculture water. The currently known heat pump system is mainly composed of evaporator condenser 1, four-way valve 2, compressor 3, condenser/evaporator 4 and capillary tube 5 to form a system as shown in Figure 1. The solid line in the figure is heating The flow direction of the process working fluid, the dotted line is the flow direction of the refrigeration process working medium. The expansion process of the working medium in this system is completed by the capillary tube, which cannot adapt to the change of ambient temperature, cannot keep the system in the best operating state, and affects the cooling and heating effect.

The purpose of the present invention is to provide a new type of aquaculture heat pump system that can operate normally in a wide range of environmental temperature changes, adapt to the requirements of aquaculture, and make it in the best operating condition in view of the above-mentioned shortcomings of the prior art.

The purpose of the present invention is achieved like this. The heat pump system includes an air heat exchanger (equivalent to an evaporator/condenser), a four-way valve, a compressor, and a water-cooled condenser (equivalent to a condenser/evaporator). The connection method of the system is basically the same as that of the existing heat pump system. , that is, the heating medium of the air heat exchanger (the working medium in the system is called the heating working medium under the heating working condition, and the cooling working medium is called the cooling working medium under the cooling working condition) outlet port and the water-cooled condenser The heating working fluid inlet ports of the compressor are respectively connected to the a and b ports of the four-way valve, and the working fluid inlet and outlet ports of the compressor are respectively connected to the c and d ports of the four-way valve. The valve can be switched to two working states of heating and cooling. In the heating state, the following two circuits are formed in the four-way valve: the first circuit is from terminal a to terminal c, and the second circuit is from terminal d to terminal b. In the cooling working condition, the four-way valve is switched into the following two circuits: the first circuit is from the b end to the c end, and the third circuit is from the d end to the a end. It is characterized in that a heating medium outlet port of the water-cooled condenser and a heating medium inlet port of the air heat exchanger are connected to a heating check valve, a liquid storage tank, a filter, and a heating expansion valve. The system connected in series as described above, and at the same time, there is a refrigeration unit with a direction opposite to that of the heating check valve between the interface between the outlet of the heating check valve and the inlet of the storage liquid and the inlet of the heating medium of the air heat exchanger. A one-way valve is connected between the outlet of the filter and the inlet of the heating expansion valve to the heating outlet of the water-cooled condenser with a refrigeration expansion valve whose expansion direction of the working medium is opposite to that of the heating expansion valve.

When the heat pump system is in the heating working state, its working process is to switch the four-way valve to the heating state. The first heating circuit (namely, end a to end c) enters the compressor, and after the working medium is heated up and pressurized, it is sent to the water-cooled condenser through the second heating circuit (namely, end d to end b) of the four-way valve. The heat is transferred to the water for aquaculture to increase the temperature of the water for aquaculture, and then the liquid working fluid condensed in the water-cooled condenser passes through the heating check valve, liquid storage tank, filter, and heating expansion valve in sequence. It expands into a low-pressure liquid working medium and returns to the air heat exchanger to evaporate into steam. In this way, the repeated cycle makes the aquaculture water reach the required water temperature.

In the cooling working state, the working process is to switch the four-way valve to the cooling state, and the working medium absorbs the heat of the aquaculture water through the water-cooled condenser (to cool down the aquaculture water) and turns it into steam, and the first refrigeration through the four-way valve The loop (that is, end b to end c) enters the compressor, and after the working medium is heated up and pressurized, it passes through the second refrigeration circuit of the four-way valve (that is, end d to end a), and is sent to the air heat exchanger to transfer heat The air is supplied, and then the liquid working medium condensed in the air heat exchanger passes through the refrigeration check valve, liquid storage tank, filter and refrigeration expansion valve in sequence, and the working medium is expanded into a low-pressure liquid working medium and then sent back to the water-cooled condenser. The purpose of cooling and cooling the breeding water is achieved through such a cycle.

In the heat pump system of the present invention, there is a circulating water pump that pumps aquaculture water (circulating water) into the water-cooled condenser to realize the forced heat exchange of aquaculture water, make it warm up or cool down, and at the same time, aquaculture water can also be cooled during the circulation process. Water has a certain oxygenation effect.

In order to avoid the liquid hammer phenomenon when the compressor is started and make the compressor suitable for use under any ambient temperature, the heat pump system is equipped with a preheating device for the compressor.

The present invention replaces the capillary used in the prior art with a working fluid expansion system composed of double expansion valves, double one-way valves, and liquid storage tanks, which can adapt to the requirements of large changes in ambient temperature to the greatest extent, so that both the refrigeration and heating processes can be at the optimum Optimum operating state, so as to ensure the working performance of the heat pump system. At the same time, because the liquid storage tank can regulate the flow rate of the working medium during the operation of the heat pump, the circulation of the working medium can be in the best condition. The invention not only can be used for heating or cooling water for aquaculture, but also has the multifunctional function of cooling or heating air.

Below is the drawing description of the present invention:

Figure 1 is a system diagram of an existing heat pump device:

Fig. 2 is a system diagram of the aquaculture heat pump device of the present invention.

Embodiments of the present invention are described in detail below in conjunction with the accompanying drawings;

The aquaculture heat pump includes: an air heat exchanger 6, a four-way valve 7 with four ports a, b, c, and d, a compressor 8, a water-cooled condenser 9, a heating check valve 10, and a refrigeration check valve 10′ , liquid storage tank 11, filter 12, heating expansion valve 13 and cooling expansion valve 13', the above-mentioned components are connected in the manner shown in Fig. 2 . The heat pump is in the heating working state. At this time, the four-way valve 7 is switched to the heating working position. At this time, the flow of the working medium flows in the direction of the solid line in Figure 2, that is, its flow direction is: air heat exchanger 6, four-way The first heating circuit of valve 7 (namely, end a to end c), compressor 8, the second heating circuit of four-way valve 7 (namely, end d to end b), water-cooled condenser 9, and heating check valve 10. Liquid storage tank 11, filter 12, heating expansion valve 13, and then return to the air heat exchanger to continue circulation. When the heat pump is in the cooling working state, switch the four-way valve 7 to the cooling working position. At this time, the flow of the working medium flows in the direction of the dotted line in Figure 2, that is, its flow direction is: the cooling of the water-cooled condenser 9 and the four-way valve 7. The first circuit (that is, end b to end c), compressor 8, the second refrigeration circuit of four-way valve 7 (that is, end d to end a), air heat exchanger b, refrigeration check valve 10', liquid storage tank 11. Filter 12, refrigeration expansion valve 13', and return to water-cooled condenser 9 to continue circulation. The water-cooled condenser directly pumps aquaculture water into the condenser through the circulating water pump 14 to form heat exchange circulating water, and has a preheating device for preheating the compressor 8 .

Claims (3)

1. An aquaculture heat pump, comprising an air heat exchanger (6), a four-way valve (7), a compressor (8) and a water-cooled condenser (9), the heating medium outlet port of the air heat exchanger (6) and The heating fluid inlet port of the water-cooled condenser (9) is respectively connected to the a-end and b-port of the four-way valve (7), and the working fluid inlet port and the working fluid outlet port of the compressor (8) are respectively connected to the four-way valve The c end and d end of (7) are characterized in that there is a heating unidirectional between the heating working medium outlet end of the water-cooled condenser (9) and the heating working medium inlet end of the air heat exchanger (6). Valve (10), liquid storage tank (11), filter (12) and heating expansion valve (13) are composed of a system connected in series in the order listed, and at the same time, the outlet of the heating check valve (10) and the liquid storage tank (11) There is a refrigeration check valve (10′) in the opposite direction to the heating check valve between the inlet port of the air heat exchanger (6) and the heating medium inlet port, and the filter (12 ) between the outlet of the heating expansion valve (13) and the heating outlet of the water-cooled condenser (9) is connected with a refrigeration expansion valve (13) whose working medium expansion direction is opposite to that of the heating expansion valve (13) '). 2. The aquaculture heat pump according to claim 1, characterized in that it has a circulating water pump (14) to pump circulating water into the water-cooled condenser (9) for forced heat exchange. 3. The aquaculture heat pump according to claim 1, characterized in that said compressor (8) is attached with a preheating device.

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