An air-conditioning and hot water system applicable to southern universities

Abstract

The present invention discloses an air-conditioning and hot water system applicable to southern universities, which is characterized in that: it includes a ground-source heat pump unit, an air-source heat pump unit, a first coil heat exchanger, a second coil heat exchanger, and a hot water exchange tank. The present invention, through the switching of two four-way valves and one three-way valve and the start-stop of the units, uses the ground-source heat pump unit as the cold and heat source of the air conditioner, and jointly uses the air-source heat pump unit to provide 45°C bathing hot water for the bathroom throughout the year. The present invention uses the ground-source heat pump unit to solve the problem of winter heating in the southern region, and according to the characteristics that the summer cooling load of buildings in the southern region is greater than the winter heating load, the ground-source heat pump unit is added to provide bathing hot water for the bathroom in winter, solving the problem of heat and cold balance in the use of the ground-source heat pump, and using the waste heat in the bathing wastewater, so that the winter heating efficiency of the air-source heat pump is as high as 4.6, and the heating efficiency of the ground-source heat pump is as high as 6.3.

Description

Technical Field

[0001] The present invention relates to the technical field of the coupled application of ground source heat pumps and air source heat pumps, and discloses an air-conditioning and hot water system suitable for southern universities. Background Art

[0002] With the increasing improvement of people's living standards, the heating demand in the southern region is becoming increasingly urgent. However, due to topographical reasons in the southern region, it is not suitable for the laying of large-scale heating pipe networks, and the summer cooling load of southern buildings is much larger than the winter heating load. If only ground source heat pump units are used for air conditioning throughout the year, the soil temperature will rise year by year. Generally, the waste heat of the soil is dissipated through a cooling tower, which will cause a waste of low-grade energy. As a heat source for bathing hot water, air source heat pumps have gradually matured in technology. However, due to the congenital deficiencies of air source heat pumps, when the outdoor temperature is relatively low in winter, their heating energy efficiency is very low. In order not to reduce their heating effect, the power consumption will increase. Moreover, there are obvious fluctuations in the bathing time of college students. During the day on weekdays, there are few bathers, and during the night on weekdays or throughout the day on weekends, there are many bathers, which causes trouble in the equipment selection of air source heat pumps. Summary of the Invention

[0003] In order to solve the defects existing in the prior art, the present invention provides an air-conditioning and hot water system suitable for southern universities, which can well solve the heating problem of universities in the southern region.

[0004] The object of the present invention is achieved through the following technical solutions: An air-conditioning and hot water system suitable for southern universities includes a ground source heat pump unit and an air source heat pump unit. It is characterized in that: the condenser ends of the ground source heat pump unit and the air source heat pump unit are connected through a first four-way valve and a second four-way valve. Among them, the condenser end of the ground source heat pump unit is connected to the a end of the first four-way valve and the a end of the second four-way valve, the condenser end of the air source heat pump unit is connected to the c end of the first four-way valve and the c end of the second four-way valve, the b end of the first four-way valve is connected to the tap water pipe, the d end of the first four-way valve is connected to the air-conditioning return pipe, the b end of the second four-way valve is connected to the bathing hot water supply pipe, the d end of the second four-way valve is connected to the air-conditioning supply pipe. The air-conditioning return pipe and the air-conditioning supply pipe are respectively connected to the indoor air outlet. A first coil heat exchanger is arranged outside the evaporator end of the air source heat pump unit. One end of the first coil heat exchanger is connected to the sewage discharge pipe, the other end is connected to the b end of the three-way valve, the c end of the three-way valve is connected to the sewage circulation pipe, the a end of the three-way valve is connected to the hot water exchange tank, the evaporator end of the ground source heat pump unit is connected to the ground source heat pump unit return pipe, and a second coil heat exchanger is arranged in series in the ground source heat pump unit return pipe, and the second coil heat exchanger is arranged in the hot water exchange tank. Further, the sewage circulation pipe is connected to the bathing wastewater discharge port.

[0005] During the refrigeration season, the a and d directions of the first four-way valve and the second four-way valve are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are closed. The ground source heat pump unit serves as the cold source for the air conditioner, and the air source heat pump unit serves as the heat source for the bath hot water.

[0006] In spring and autumn, the a and d directions of the first four-way valve and the second four-way valve are closed, and the b and c directions are connected. The a, b, and c directions of the three-way valve are closed. The air source heat pump unit serves as the heat source for the bath hot water, and the ground source heat pump unit is turned off.

[0007] A temperature detector is installed at the condenser end of the air source heat pump unit. During the day in the heating season and when the temperature detector T1≥40°C, the a and d directions of the first four-way valve and the second four-way valve are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are opened. The ground source heat pump unit serves as the heat source for the air conditioner, and the air source heat pump unit serves as the heat source for the bath hot water; during the night in the heating season or when the temperature detector T1<40°C, the a and b directions, a and d directions, and b and c directions of the first four-way valve and the second four-way valve are connected. The a, b, and c directions of the three-way valve are opened. The ground source heat pump unit serves as the heat source for the air conditioner and the bath hot water, and the air source heat pump unit serves as the heat source for the bath hot water.

[0008] By switching the above valves and starting and stopping the units, the problem of unbalanced heating and cooling of the ground source heat pump unit is solved, and the service life of the unit is extended. By utilizing the waste heat in the bath wastewater, the heating energy efficiency of the air source heat pump unit in winter can reach 4.6, and the heating energy efficiency of the ground source heat pump unit can reach 6.3.

[0009] Beneficial effects: Through the present invention, the heating problem of colleges and universities in the southern region is solved. The ground source heat pump is used as one of the heat sources for the bath hot water, avoiding the problem of unbalanced heating and cooling of the soil. At the same time, the problem of the selection size of the air source heat pump due to the fluctuation of the number of bathers is also solved. The waste heat in the bath wastewater is recovered in winter to heat the air temperature entering the evaporator of the air source heat pump and the temperature of the circulating liquid in the return pipe of the ground source heat pump unit respectively, improving the energy efficiency of the units. Description of the Drawings

[0010] Figure 1 It is a diagram of an air-conditioning hot water system applicable to colleges and universities in the south. Detailed Embodiments

[0011] Refer to the attached Figure 1 and the embodiments to further describe the present invention in detail:

[0012] In the figure, there are a ground source heat pump unit 1, an air source heat pump unit 2, a first coil heat exchanger 3, a sewage pipe 1, a tap water pipe 5, a bath hot water supply pipe 6, a sewage circulation pipe 7, a sewage pipe 2, a hot water exchange tank 9, a second coil heat exchanger 10, a return pipe of the ground source heat pump unit 11, a supply pipe of the ground source heat pump unit 12, an air conditioner return pipe 13, and an air conditioner supply pipe 14.

[0013] An air-conditioning hot water system applicable to southern universities, characterized in that it includes a ground source heat pump unit 1, an air source heat pump unit 2, a first coil heat exchanger 3, a second coil heat exchanger 10, and a hot water exchange tank 9. The four directions a, b, c, and d of the first four-way valve S1 are respectively connected to the ground source heat pump unit 1, the tap water pipe 5, the air source heat pump unit 2, and the air conditioner return pipe 13. The four directions a, b, c, and d of the second four-way valve S2 are respectively connected to the ground source heat pump unit 1, the bath hot water supply pipe 6, the air source heat pump unit 2, and the air conditioner supply pipe 14. The first coil heat exchanger 3 and the hot water exchange tank 9 are connected in parallel through a three-way valve S3, and the second coil heat exchanger 10 is placed inside the hot water exchange tank 9.

[0014] In the cooling season, the a and d directions of the four-way valves S1 and S2 are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are closed. The ground source heat pump unit 1 serves as the cold source for the air conditioner, and the air source heat pump unit 2 serves as the heat source for the bath hot water.

[0015] In spring and autumn, the a and d directions of the four-way valves S1 and S2 are closed, and the b and c directions are connected. The a, b, and c directions of the three-way valve are closed. The air source heat pump unit 2 serves as the heat source for the bath hot water, and the ground source heat pump unit 1 is turned off.

[0016] During the day in the heating season and when the temperature detector T1≥40°C, the a and d directions of the first four-way valve S1 and the second four-way valve S2 are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are opened. The ground source heat pump unit 1 serves as the heat source for the air conditioner, and the air source heat pump unit 2 serves as the heat source for the bath hot water.

[0017] During the night in the heating season or when the temperature detector T1<40°C, the a and b directions of the first four-way valve S1 and the second four-way valve S2 are connected, the a and d directions are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are opened. The ground source heat pump unit 1 serves as the heat source for the air conditioner and the bath hot water, and the air source heat pump unit 2 serves as the heat source for the bath hot water.

[0018] By using the switching of the above valves and the start and stop of the units, the problem of heat and cold imbalance of the ground source heat pump unit 1 is solved, and the service life of the unit is extended.

[0019] By using the waste heat in the bath wastewater, the winter heating energy efficiency of the air source heat pump unit 2 is as high as 4.6, and the heating energy efficiency of the ground source heat pump unit 1 is as high as 6.3. Embodiment

[0020] Example 1: In the cooling season, the first four-way valve S1 and the second four-way valve S2 are connected in directions a and d, and in directions b and c, and the three-way valves a, b, and c are closed. The ground source heat pump unit 1 is used as the cold source of the air conditioner, and the air source heat pump unit 2 is used as the heat source of the hot water for bathing. The ground source heat pump unit 1 provides 7°C chilled water to the air conditioning terminal (i.e., the indoor exhaust port) in the building through the air conditioning water supply pipe 14. The air conditioning return pipe 13 sends the chilled water heated to 12°C back to the ground source heat pump unit 1 for cooling. The tap water enters the air source heat pump unit 2, is heated to about 45°C, and is sent to the bathing terminal through the hot water supply pipe 6 for bathing.

[0021] Example 2: In spring and autumn, the a and d directions of the first four-way valve S1 and the second four-way valve S2 are closed, the b and c directions are connected, and the a, b, and c directions of the three-way valves are closed. At this time, the indoor personnel have no cooling and heating needs, so the ground source heat pump unit 1 is turned off, and the air source heat pump unit 2 is used as a heat source to provide people with hot water for bathing at a suitable temperature.

[0022] Example 3: During the daytime in the heating season and when the temperature detector T1 is ≥40°C, the first four-way valve S1 and the second four-way valve S2 are connected in directions a and d, and in directions b and c. The three-way valves in directions a, b and c are opened. The ground source heat pump unit 1 serves as the heat source for the air conditioner and uses the heat storage and electrical energy of the soil during the cooling season to provide 45°C hot water to the indoor air conditioning terminal (i.e., the indoor exhaust vent). At this time, the heating efficiency of the air source heat pump unit 2 is relatively high and can bear all the heat load of the hot water for bathing. The air source heat pump unit 2 serves as the only heat source for the hot water for bathing.

[0023] Embodiment 4: In the night of the heating season or when the temperature detector T1 is less than 40°C, the a and b directions of the first four-way valve S1 and the second four-way valve S2 are connected, the a and d directions are connected, the b and c directions are connected, and the a, b and c directions of the three-way valves are opened. Since the cooling load of buildings in the south in summer is much greater than the heating load in winter, if the ground source heat pump unit 1 is only used as a cold and hot source for air conditioning, the heat supplied to the soil will be much greater than the heat extracted from the soil, causing the soil temperature to rise year by year and the refrigeration efficiency to decrease year by year until the ground source heat pump unit 1 cannot cool. The air source heat pump unit 2 has a low heating efficiency at night in winter due to the low outdoor temperature, and the number of people taking baths at night is much greater than the number of people taking baths during the day. Therefore, the use of the air source heat pump unit 2 alone cannot meet the bathing requirements. Therefore, using the air source heat pump unit 2 as a heat source for air conditioning and bathing not only solves the problem of hot and cold imbalance in the soil, but also solves the problem of insufficient heating capacity of the air source heat pump unit 2 for bathing.

[0024] In Embodiment 3 and Embodiment 4, the low-grade thermal energy in the bath wastewater is used to heat the air temperature entering the air source heat pump unit 2 and the temperature of the circulating liquid in the return water pipe 11 of the ground source heat pump unit respectively, so that the heating energy efficiency of the air source heat pump unit 2 in winter is as high as 4.6, and the heating energy efficiency of the ground source heat pump unit 1 is as high as 6.3, reducing the power consumption. At the same time, it also avoids the heat pollution phenomenon caused by the random discharge of bath hot water.

[0025] Although the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, it is not a limitation to the protection scope of the invention. Those skilled in the art should understand that, based on the technical solutions of the present invention, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present invention.

Claims

1. An air-conditioning and hot water system applicable to southern universities, comprising a ground-source heat pump unit and an air-source heat pump unit, characterized in that: The condenser end of the ground-source heat pump unit and the condenser end of the air-source heat pump unit are connected through the first four-way valve and the second four-way valve. Among them, the condenser end of the ground-source heat pump unit is connected to the a end of the first four-way valve and the a end of the second four-way valve, and the condenser end of the air-source heat pump unit is connected to the c end of the first four-way valve and the c end of the second four-way valve. The b end of the first four-way valve is connected to the tap water pipe, and the d end of the first four-way valve is connected to the air-conditioning return water pipe. The b end of the second four-way valve is connected to the bath hot water supply pipe, and the d end of the second four-way valve is connected to the air-conditioning supply water pipe. The air-conditioning return water pipe and the air-conditioning supply water pipe are respectively connected to the indoor air outlet. A first coil heat exchanger is arranged outside the evaporator end of the air-source heat pump unit. One end of the first coil heat exchanger is connected to the sewage discharge pipe, and the other end is connected to the b end of the three-way valve. The c end of the three-way valve is connected to the sewage circulation pipe, and the a end of the three-way valve is connected to the hot water exchange tank. The evaporator end of the ground-source heat pump unit is connected to the ground-source heat pump unit return water pipe, and a second coil heat exchanger is arranged in series in the ground-source heat pump unit return water pipe. The second coil heat exchanger is arranged in the hot water exchange tank; in the cooling season, the a and d directions of the first four-way valve and the second four-way valve are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are closed. The ground-source heat pump unit serves as the cold source for the air conditioner, and the air-source heat pump unit serves as the heat source for the bath hot water; in spring and autumn, the a and d directions of the first four-way valve and the second four-way valve are closed, and the b and c directions are connected. The a, b, and c directions of the three-way valve are closed. The air-source heat pump unit serves as the heat source for the bath hot water, and the ground-source heat pump unit is turned off; at the condenser end of the air-source heat pump unit, a temperature detector is arranged. During the day in the heating season and when the temperature detector T1≥40°C, the a and d directions of the first four-way valve and the second four-way valve are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are opened. The ground-source heat pump unit serves as the heat source for the air conditioner, and the air-source heat pump unit serves as the heat source for the bath hot water; at night in the heating season or when the temperature detector T1<40°C, the a and b directions of the first four-way valve and the second four-way valve are connected, the a and d directions are connected, and the b and c directions are connected. The a, b, and c directions of the three-way valve are opened. The ground-source heat pump unit serves as the heat source for the air conditioner and the bath hot water, and the air-source heat pump unit serves as the heat source for the bath hot water.

2. The air-conditioning and hot water system applicable to southern universities according to claim 1, wherein: The sewage circulation pipe is connected to the bath wastewater discharge outlet.

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