CN100559096C - A water source heat pump unit capable of automatically backwashing sewage - Google Patents

Abstract

A water source heat pump unit capable of automatically backwashing sewage relates to the technical field of air conditioning. The invention includes a compression evaporation condensation unit composed of a compressor, a condenser, an expansion valve, an evaporator and a four-way valve. Its structural feature is that a filter 1, a water pump, a three-way valve and a filter 2 connected to the sewage source are sequentially connected in series on the water supply pipeline of the evaporator. The return water pipeline of the evaporator is connected in series with the electric valve 2 connected with the drainage tank. A differential pressure sensor is connected in parallel between the inlet and outlet of the evaporator. An electric valve one is connected in parallel between the junction of the filter two and the three-way valve and the outlet of the electric valve two, and the other outlet of the three-way valve is connected with the inlet end of the electric valve two. The top of the evaporator is provided with a sewage pipe, and an electric valve three is arranged on the sewage pipe. Compared with the prior art, the present invention can directly exchange heat between industrial waste water or sewage resources and the refrigerant heat exchanger, reduces the heat transfer temperature difference of the heat exchanger, improves the efficiency of the unit, and reduces the equipment cost.

Description

A water source heat pump unit capable of automatically backwashing sewage

technical field

The invention relates to the technical field of air conditioning, in particular to a water source heat pump unit that uses sewage as a water source and can be automatically backwashed.

Background technique

The water source heat pump is a heat pump type integrated water-water/water-air air conditioning device that uses water as the medium for refrigeration/heating cycles. The water source heat pump unit uses water as the heat source when heating, and uses water as the heat exhaust source when cooling. The advantages of using water as a heat source are: the heat capacity of water is large, the heat transfer performance is good, the amount of water required to transfer a certain amount of heat is small, the size of the heat exchanger is compact, and the cost per square meter of building area is less than that of air-air heat pumps , and will not frost, the water temperature changes relatively small, and the operating conditions are stable. Water source heat pump units can use seawater, lake water, river water, groundwater and geothermal tail water. At present, groundwater is the most commonly used, but the groundwater recharge technology is not very mature, and it is unpredictable whether it will pollute and damage precious groundwater resources. The water source heat pump unit can also use industrial wastewater and sewage resources, but when using sewage resources, an intermediate heat exchanger must be added to prevent the sewage from corroding the heat exchanger, which increases the heat transfer temperature difference of the heat exchanger and reduces the temperature of the unit. Efficiency, but also increased the cost of the unit.

Contents of the invention

In view of the deficiencies in the above-mentioned prior art, the object of the present invention is to provide a water source heat pump unit capable of automatically backwashing sewage. The unit can directly exchange heat between industrial wastewater or sewage resources and the refrigerant heat exchanger, which reduces the heat transfer temperature difference of the heat exchanger, improves the efficiency of the unit, and reduces the equipment cost.

In order to achieve the above-mentioned purpose of the invention, the technical solution of the present invention is realized in the following manner:

A water source heat pump unit capable of automatically backwashing sewage, which includes a compression evaporation condensing unit composed of a compressor, a condenser, an expansion valve, an evaporator and a four-way valve. Both the condenser and the evaporator are water heat exchangers. Its structural feature is that a filter 1, a water pump, a three-way valve and a filter 2 connected to the sewage source are sequentially connected in series on the water supply pipeline of the evaporator. The return water pipeline of the evaporator is connected in series with the electric valve 2 connected with the drainage tank. A differential pressure sensor is connected in parallel between the water supply pipeline and the return water pipeline of the evaporator. An electric valve one is connected in parallel between the junction of the filter two and the three-way valve and the outlet of the electric valve two, and the other outlet of the three-way valve is connected with the inlet end of the electric valve two. The top of the evaporator is provided with a sewage pipe, and an electric valve three is arranged on the sewage pipe.

In the above water source heat pump unit, the condenser and evaporator adopt a flooded structure, the heat exchange tubes are made of anti-corrosion white copper, and the end caps at both ends of the condenser and evaporator are built with highly reducing metal.

Compared with the prior art, the present invention has the following advantages due to the above-mentioned structure:

1. It can make full use of water resources such as industrial wastewater and sewage, expand the water source range of the water source heat pump system, and reduce the damage to groundwater resources.

2. Industrial wastewater and sewage can directly enter the heat exchanger of the unit for heat exchange without causing corrosion to the heat exchanger, reducing the heat transfer temperature difference, improving the efficiency of the unit, and saving equipment costs.

3. The automatic backwashing device added on the side of the heat exchanger can prevent the solid particles in the sewage from forming blockage in the heat exchanger.

4. The unit system is equipped with a four-way reversing valve, so that no matter whether it is cooling or heating, the water source on the user side does not need to be switched.

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings

Accompanying drawing is the structural representation of the present invention.

Detailed ways

Referring to the accompanying drawings, the present invention includes a compression evaporation condensation unit composed of a compressor 1 , a condenser 2 , an expansion valve 10 , an evaporator 4 and a four-way valve 7 . Both the condenser 2 and the evaporator 4 are flooded water heat exchangers, in which the heat exchange tubes are made of anti-corrosion white copper, and the end caps at both ends of the condenser 2 and the evaporator 4 are built with highly reducing metals. A filter one 8.1, a water pump 9, a three-way valve 6 and a filter two 8.2 connected to the sewage source are sequentially connected in series on the water supply pipeline of the evaporator 4. The return water pipeline of evaporator 4 is connected in series with the electric valve two 5.2 that is connected with drainage tank. A differential pressure sensor 3 is connected in parallel between the water supply pipeline and the return water pipeline of the evaporator 4 . An electric valve one 5.1 is connected in parallel between the junction of the filter two 8.2 and the three-way valve 6 and the outlet of the electric valve two 5.2, and the other outlet of the three-way valve 6 is connected with the inlet end of the electric valve two 5.2. The top of the evaporator 4 is provided with a blowdown pipe, and an electric valve 3 5.3 is placed on the blowdown pipe.

When the present invention is used, the low-temperature gaseous refrigerant is inhaled by the suction valve of the compressor 1 and compressed by the compressor 1, and becomes a high-temperature and high-pressure refrigerant gas and enters the condenser 2 through the four-way valve 7 . The refrigerant gas transfers heat to the end of the user to generate hot water for heating. The high-temperature and high-pressure liquid refrigerant coming out of the condenser 2 passes through a dry filter to remove moisture and impurities, and then flows through the expansion valve 10 to reduce pressure and become low temperature. The low pressure liquid refrigerant enters the evaporator 4. In the evaporator 4, the low-temperature and low-pressure liquid refrigerant absorbs the heat of the circulating cold water and evaporates continuously. When it reaches the outlet of the evaporator 4, it has all become low-temperature and low-pressure superheated dry steam, and then returns to the suction of the compressor 1 through the four-way valve 7. The valve is recycled. The circulating cold water in the evaporator 4 adopts industrial wastewater or sewage, and the water pump 9 is opened, and the sewage enters the evaporator 4 through a filter one 8.1, a water pump 9, a three-way valve 6 and a filter two 8.2. When the electric valve two 5.2 is opened and the electric valve one 5.1 is closed, the sewage after heat exchange is discharged from the return pipe of the evaporator 4 to the drainage pool through the electric valve two 5.2.

When the pipeline of the evaporator 4 is blocked, the evaporator 4 is automatically backwashed and drained. Open the water pump 9 and close the electric valve two 5.2. The water enters the evaporator 4 through the bypass of the filter one 8.1, the water pump 9, the three-way valve 6 and the return line of the evaporator 4. Open the electric valve one 5.1 and electric valve three 5.3, the sewage after flushing is discharged through the filter two 8.2 and electric valve one 5.1 on the water supply pipeline of the evaporator 4 through the return water pipe of the evaporator 4, and the other sewage is discharged through the electric valve 3.5.3 Direct discharge.

The start of the above automatic backwashing program can detect and transmit the pressure change signal through the differential pressure sensor 3, control the opening and closing of the electromagnetic valve in the corresponding pipeline, and perform the backwashing function. It is also possible to perform the timing backwashing function according to the artificial setting time.

Of course, the present invention can also be used for refrigeration. It only needs to switch the four-way valve 7 and change the flow direction sequence of the refrigerator, so that the condenser 2 can provide cooling water for the end user. These all belong to the prior art and will not be repeated here.

Claims (2)

1. A water source heat pump unit capable of automatically backwashing sewage, which includes a compressor (1), a condenser (2), an expansion valve (10), an evaporator (4) and a four-way valve (7). The evaporative condensing unit, the condenser (2) and the evaporator (4) are both water heat exchangers, and it is characterized in that the water supply pipeline of the evaporator (4) is sequentially connected with a filter connected to a sewage source ( 8.1), water pump (9), three-way valve (6) and filter two (8.2), the electric valve two (5.2) connected to the drainage pool is connected in series on the return water pipeline of the evaporator (4), and the evaporator ( 4) There is a differential pressure sensor (3) connected in parallel between the water supply pipeline and the return water pipeline, between the connection between the filter two (8.2) and the three-way valve (6) and the outlet of the electric valve two (5.2) Electric valve one (5.1) is connected in parallel between them, the other outlet of the three-way valve (6) is connected to the inlet of electric valve two (5.2), the top of the evaporator (4) is provided with a sewage pipe, and the sewage pipe is equipped with Electric valve three (5.3). 2. The water source heat pump unit according to claim 1, characterized in that the condenser (2) and evaporator (4) adopt a flooded structure, the heat exchange tubes are made of anti-corrosion white copper, and the condenser ( 2) and the end caps at both ends of the evaporator (4) are built with highly reducing metal.

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