CN202613556U - Ground source heat pump heating system utilizing heating terminals for free cooling - Google Patents

Abstract

The invention relates to a ground source heat pump heating system which utilizes a heating terminal for free cooling, and belongs to the technical field of heating and air conditioning. The heating system adds a free cooling loop on the basis of the conventional ground source heat pump system. In winter, ground source heat pumps are used to extract heat from the ground, and hot water is supplied to the heating terminal; Free cold. The utility model makes full use of the existing natural cold source at the heating end, not only provides free cooling for the building, reduces the load of the air conditioner, but also realizes the heat supplement for the underground soil, and alleviates the problem caused by the ground source heat pump taking heat from the ground for many years. The problem of soil temperature drop and heat pump performance degradation. For systems equipped with supplementary heat equipment such as solar energy, it can also reduce the capacity of supplementary heat equipment and save investment.

Description

A ground source heat pump heating system using free cooling at the heating end

technical field

The utility model relates to a ground source heat pump heating system, which belongs to the technical field of heating and air conditioning.

Background technique

my country's building heating consumes a lot of energy. Of the building energy consumption that accounts for 22% to 25% of the total energy consumption in society, about 40% is used for building heating. Among them, the energy consumption of heating network centralized heating or community centralized heating in northern urban areas accounts for about 60% of the total energy consumption of building heating. With the rapid increase of building area, heating demand will also increase significantly. Therefore, heating energy saving is the top priority of building energy saving in my country.

Heating in northern cities and towns is mainly based on centralized heating based on fossil fuel combustion, which not only has low energy efficiency but also causes heavy pollution. The average efficiency of coal-fired boilers is only 65%. Even for gas-fired boilers with an efficiency of more than 90%, the primary energy efficiency of heating is lower than 100%. In recent years, the ground source heat pump system has been widely used because it is regarded as a renewable energy utilization technology. However, the ground source heat pump system has an imbalance of heat intake in winter and heat discharge in summer, and long-term operation will cause the soil temperature to drop year by year; will be more serious. This will cause a significant attenuation of the performance of the unit, or even fail to operate normally at all, and the reliability of heating cannot be better guaranteed. For absorption heat pumps, under the same conditions, the drop in soil temperature is significantly smaller than that of electric heat pumps due to the small amount of heat taken from the soil. However, the long-term operation of the absorption heat pump system cannot completely solve the problems of soil temperature drop and heat pump heating performance attenuation. At present, among the commonly used solutions to solve the problem of soil heat imbalance in ground source heat pump systems, increasing the spacing of buried pipes occupies a large area and has limited mitigation capabilities; the energy efficiency of boiler auxiliary heat sources is low; and the reliability of solar heat supplementation is poor. Therefore, the soil heat imbalance and performance attenuation of the ground source heat pump system are urgent problems to be solved to ensure the reliability of heating supply and energy-saving operation in the northern region.

Utility model content

The purpose of this utility model is to propose a ground source heat pump heating system that uses the heating terminal for free cooling. The system makes full use of the existing heating terminal and underground natural cold source to provide free cooling for the building. For buildings without air conditioning, additional cooling capacity can be provided; for buildings with heating and air conditioning systems, the cooling load of the air conditioning system can be reduced. Moreover, the cooling at the heating end can also store the indoor waste heat in the ground to realize the heat supplement to the soil, thereby effectively alleviating the decrease of the ground temperature and the performance attenuation of the ground source heat pump heating system. For systems equipped with supplementary heating equipment, the capacity of supplementary heating equipment can also be reduced to save initial investment.

The technical scheme of the utility model is as follows:

A ground source heat pump heating system that uses free cooling at the heating terminal, the system includes a ground source heat pump unit, a user-side water pump, a heating terminal, a ground source side water pump, and an underground heat exchange system; the user-side outlet of the ground source heat pump unit The user side water pump is connected to the inlet of the heating terminal, the user side inlet of the ground source heat pump unit is connected to the outlet of the heating terminal; the outlet of the underground heat exchange system is connected to the ground source side inlet of the ground source heat pump unit through the ground source side water pump , the inlet of the underground heat exchange system is connected to the outlet of the ground source side of the ground source heat pump unit; it is characterized in that: a free cooling water supply pipeline is added between the outlet of the water pump on the ground source side and the inlet of the heating terminal, and the outlet of the heating terminal is connected to the A free cooling return water pipeline is added between the entrances of the underground heat exchange system, and a second valve is provided on the free cooling water supply pipeline; the underground heat exchange system, the free cooling water supply pipeline, the heating terminal and the free The cooling return water pipeline constitutes a free cooling loop at the heating end.

The ground source heat pump heating system using the heating terminal for free cooling is characterized in that: the heating terminal adopts radiators, radiant panels or fan coils. The underground heat exchange system is a buried tube heat exchanger or an underground water well. The ground source heat pump unit is an electric heat pump or an absorption heat pump.

Compared with the existing system, the utility model has the following advantages and beneficial effects: ① Make full use of the existing heating terminal and underground natural cold source to realize free cooling; It can effectively alleviate the reduction of ground temperature and the performance attenuation of the ground source heat pump heating system; ③ For buildings with two systems of heating and air conditioning, it can reduce the cooling load of the air conditioning system; ④ For buildings equipped with supplementary heat The system of equipment can also reduce the capacity of supplementary heating equipment and reduce the initial investment.

Generally speaking, the utility model is an energy-saving and environment-friendly heating system. It is especially suitable for buildings with heating demand in winter but low air-conditioning requirements or no air-conditioning in summer; for buildings with separate heating and air-conditioning systems, cooling at the heating end can be used to reduce the cooling load of the air-conditioning system; The system of heating equipment can also reduce the capacity of supplementary heating equipment and reduce the initial investment.

Description of drawings

Fig. 1 is a structural schematic diagram of a ground source heat pump heating system disclosed by the utility model that uses free cooling at the heating end.

Fig. 2 is a schematic diagram of the winter heating mode of the present invention.

Fig. 3 is a schematic diagram of the free cooling mode of the utility model in summer.

In the figure: 1-ground source heat pump unit; 2-user side water pump; 3-heating terminal; 4-first valve; 5-ground source side water pump; 6-underground heat exchange system; 7-second valve; 8-free Cooling water supply pipeline; 9-free cooling water return pipeline.

Detailed ways

Below in conjunction with accompanying drawing, structure, principle and working process of the present utility model are described further.

Fig. 1 is a structural schematic diagram of a ground source heat pump heating system disclosed by the utility model that uses the heating terminal for free cooling. The system includes a ground source heat pump unit 1, a user-side water pump 2, a heating terminal 3, a ground-source side water pump 5 and Underground heat exchange system 6; the user-side outlet of the ground source heat pump unit 1 is connected to the inlet of the heating terminal 3 through the user-side water pump 2, and the user-side inlet of the ground source heat pump unit 1 is connected to the outlet of the heating terminal 3; the underground The outlet of the heat exchange system 6 is connected to the ground source side inlet of the ground source heat pump unit 1 through the ground source side water pump 5 , and the inlet of the underground heat exchange system 6 is connected to the ground source side outlet of the ground source heat pump unit 1 . A free cooling water supply pipeline 8 is added between the outlet of the water pump 5 on the ground source side and the inlet of the heating terminal 3, and a free cooling return water pipeline 9 is added between the outlet of the heating terminal 3 and the inlet of the underground heat exchange system 6, And a second valve 7 is provided on the free cooling water supply pipeline 8; the underground heat exchange system 6, the free cooling water supply pipeline 8, the heating terminal 3 and the free cooling return water pipeline 9 constitute the heating terminal Free cooling loop. In summer, the outlet water of the underground heat exchange system is directly sent to the heating terminal 3 of the building through the ground source side water pump 5 to realize free cooling, and the flow rate of the ground source side water pump 5 or the opening of the second valve 7 is controlled to enter Water temperature at heating end 3. The heating terminal 3 can adopt radiators, various radiant panels or fan coils. The underground heat exchange system 6 adopts a buried tube heat exchanger or an underground water well. The ground source heat pump unit 1 is an electric heat pump or an absorption heat pump.

Fig. 2 is a schematic diagram of the winter heating mode of the present invention. In the heating period, the second valve 7 is closed, and the brine at the outlet of the underground heat exchange system 6 is absorbed and cooled in the evaporator of the ground source heat pump unit 1, and then returns to the underground heat exchange system 6, and the ground source heat pump unit 1 extracts the brine. The heat in the refrigerant is then used to produce hot water for heating and enter into the heating terminal 3 through the user-side water pump 2 to provide heat for the user.

Fig. 3 is a schematic diagram of the free cooling mode of the utility model in summer. For buildings without an air conditioning system or with a separate air conditioning system, in summer, the ground source side water pump 5 sends the cold water from the outlet of the underground heat exchange system 6 directly to the heating terminal 3 through the free cooling water supply pipeline 8, which provides free cooling for the building. For cooling, after absorbing heat in the heating terminal 3 and raising the temperature, it returns to the underground heat exchange system 6 to discharge heat and cool down, forming a free cooling cycle, and at the same time replenishing heat to the soil. When the temperature of the cold water at the outlet of the underground heat exchange system 6 is low so that the heating terminal 3 may condense, the flow rate of the ground source side water pump 5 or the opening of the second valve 7 can be adjusted to appropriately increase the temperature of the cold water. When the condensation of the heating terminal 3 cannot be avoided by adjusting the flow rate or the opening degree, the free cooling can be appropriately stopped. For the heating end of the fan coil unit, there is no need to consider the risk of condensation.

Claims (4)

1. earth source heat pump heating system of utilizing the terminal free cold supply of heating, comprise earth source heat pump unit (1), user side water pump (2), heating terminal (3), source water pump (5) and underground heat exchange system (6); The user side outlet of said earth source heat pump unit (1) links to each other through the inlet of user side water pump (2) with heating terminal (3), and the user side inlet of earth source heat pump unit (1) links to each other with the outlet of heating terminal (3); The outlet of said underground heat exchange system (6) links to each other with the ground source inlet of earth source heat pump unit (1) through ground source water pump (5), and the inlet of underground heat exchange system (6) links to each other with the ground source outlet of earth source heat pump unit (1); It is characterized in that: between ground source water pump (5) outlet and heating terminal (3) inlet, increased free cold supply supply channel (8); Between the inlet of the outlet of heating terminal (3) and underground heat exchange system (6), increase free cold supply water return pipeline (9), and on free cold supply supply channel (8), be provided with second valve (7); Described underground heat exchange system (6), free cold supply supply channel (8), heating terminal (3). constituted the terminal free cold supply loop of heating with free cold supply water return pipeline (9).

2. a kind of earth source heat pump heating system of utilizing the terminal free cold supply of heating according to claim 1 is characterized in that: radiator, radiant panel or fan coil are adopted in said heating terminal (3).

3. a kind of earth source heat pump heating system of utilizing the terminal free cold supply of heating according to claim 1, it is characterized in that: said underground heat exchange system (6) is ground heat exchanger or underground water well.

4. a kind of earth source heat pump heating system of utilizing the terminal free cold supply of heating according to claim 1, it is characterized in that: said earth source heat pump unit (1) is electric heating pump or absorption heat pump.

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