Heat pump heat supply system for storing solar energy in soil

Abstract

The invention provides a heat pump heat supply system for storing solar energy in soil. The heat pump heat supply system comprises a heat collector, a buried pipe, an evaporator, a one-way valve, a compressor, an expansion valve, a refrigerant pump and a condenser. And the heat collector, the evaporator and the buried pipe are communicated with one another. When light and heat are rich, part of hot water generated by the heat collector accumulates heat into the soil through the buried pipe, and when light and heat are insufficient, the heat accumulated in the soil is released through the buried pipe to supply heat to the outside. When the temperature of hot water generated by the heat collector is low, the compressor operates, and a refrigerant flowing out of the evaporator enters the compressor, enters the condenser for condensation and heat release after being compressed and then returns to the evaporator after passing through the expansion valve, so that circulation is completed. When the temperature of hot water generated by the heat collector is high, the compressor and the expansion valve are closed, the refrigerant pump operates, and a refrigerant flowing out of the evaporator enters the condenser after passing through the one-way valve and returns to the evaporator through the refrigerant pump after releasing heat in the condenser to complete circulation. On one hand, the contradiction between photo-thermal resource intermittency and thermal load demand continuity is solved, decoupling between photo-thermal resources and thermal load demands of heat consumers is achieved through soil heat storage and release, the comprehensive utilization efficiency of solar energy is effectively improved, and on the other hand, under the condition that normal circulation of refrigerants is guaranteed, the energy consumption of the refrigerants is reduced. The compressor is switched out, the heat supply system is prevented from being limited by the minimum rotating speed of the compressor, efficient and flexible adjustment of large-range variable working conditions is achieved, heat supply energy consumption is reduced, and the system operation economical efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the field of new energy heating, and in particular relates to a heat pump heating system that stores solar energy in soil. Background Art

[0002] With the development of urban construction, increasing the proportion of renewable energy applications and reducing the use of fossil energy are important measures to help build low-carbon green towns, among which the use of solar energy is the most common. Absorbing solar heat through collectors and using heat pump technology for heating is an effective way to reduce building energy consumption. However, in the use of solar thermal resources, there is a contradiction between the intermittent nature of solar thermal energy and the continuous heating load demand of users, which limits the application of solar heat pump heating systems. In addition, when the light is strong, the outlet water temperature of the solar collector is high, close to or even exceeding the water supply temperature requirements of heat users, which causes the heat pump compressor to fail to operate normally. It is necessary to lower the collector water temperature to ensure the normal operation of the solar heat pump heating system, which increases the heating energy consumption and significantly reduces the comprehensive utilization efficiency of energy.

[0003] The invention patent with publication number CN116697639A discloses a solar-air source heat pump coupling system, which supplements intermittent solar energy through air energy, that is, when the light and heat are insufficient, heat is taken from the air, but when the light and heat are sufficient, the surplus light and heat cannot be used due to the lack of heat storage, resulting in energy waste. In addition, when the hot water temperature of the collector plate is high, the compressor cannot be started and solar energy cannot be used for heating, which significantly reduces the energy utilization efficiency. The invention patent with publication number CN116518584A discloses a ground source heat pump heat compensation system, which combines light and heat with ground heat to solve the contradiction between the intermittent nature of light and heat and the continuous heat load demand of heat users, but the hot water generated by the collector is exchanged with the heat source water of the heat pump through a heat exchanger, which increases the heat exchange link. In addition, when the hot water temperature generated by the collector is high, it is still limited by the operation of the compressor and cannot be fully utilized, and the comprehensive utilization efficiency of energy is low.

[0004] It can be seen that it is of great significance to propose a soil-storage solar energy heat pump heating system that can achieve the decoupling between solar thermal resources and the heat load demand of heat users, resolve the contradiction between the intermittent nature of solar thermal energy and the continuous heat load demand of heat users, overcome the operating limitations of the compressor, achieve efficient and flexible adjustment of the heat pump over a wide range of variable operating conditions, and improve the utilization efficiency of high-temperature solar thermal resources. Summary of the invention

[0005] (I) Purpose of the invention

[0006] The purpose of the present invention is to provide a heat pump heating system for storing solar energy in the soil. By arranging solar thermal pipes and buried pipes, the soil can be used to store solar energy, and the decoupling between solar thermal resources and the thermal load requirements of heat users can be achieved, thereby effectively improving the comprehensive utilization efficiency of energy. In addition, the present invention also arranges a one-way valve and a refrigerant pump. When the solar thermal temperature is high and the water supply temperature of the heat user is low, the compressor can be cut out while ensuring the normal circulation of the Freon refrigerant, thereby achieving efficient and flexible adjustment of the heat pump under a wide range of variable operating conditions, reducing the heating energy consumption, and improving the economy of the system operation.

[0007] (II) Technical solution

[0008] In order to solve the above problems, the present invention provides a soil-storage solar energy heat pump heating system in a first aspect, comprising:

[0009] Collector, buried pipe, evaporator, check valve, compressor, expansion valve, refrigerant pump, condenser.

[0010] The collector is connected to the evaporator, and at the same time, the collector is connected to the underground pipe. When the solar energy is relatively abundant and exceeds the user's heat load demand, part of the hot water at the collector outlet enters the evaporator to cool down and release heat, and the other part enters the underground pipe, exchanges heat with the soil through the underground pipe, and stores the heat in the soil; when the solar energy is less and cannot meet the user's heat load demand, part of the heat source water at the evaporator outlet enters the collector, absorbs solar energy and heats up before returning to the evaporator, and the other part of the cold water enters the underground pipe, exchanges heat with the surrounding soil and heats up before returning to the evaporator, and the soil releases the stored heat, realizing the storage and release cycle of solar energy.

[0011] When the hot water temperature at the collector outlet is low and the water temperature of the heat user is high, the compressor runs and the refrigerant pump is turned off. The refrigerant vapor at the evaporator outlet enters the compressor for compression, and the refrigerant vapor after pressure increase enters the condenser, where it condenses and releases heat. The condensed liquid refrigerant enters the evaporator for evaporation after pressure reduction by the expansion valve, completing the refrigerant cycle.

[0012] When the hot water temperature at the collector outlet is high and the water temperature of the heat user is low, the compressor stops running, the refrigerant pump runs, and the expansion valve is closed. The refrigerant at the evaporator outlet flows through the one-way valve and enters the condenser, exchanges heat in the condenser, flows out, passes through the refrigerant pump, and returns to the evaporator to absorb heat, completing the refrigerant cycle.

[0013] The return water from hot users enters the condenser, and after being heated in the condenser, it flows out as supply water for hot users.

[0014] Furthermore, it also includes: a first circulation pump and a second circulation pump. The inlet of the first circulation pump is connected to the heat source water outlet of the evaporator, and the outlet of the first circulation pump is connected to the inlet of the collector; the inlet of the second circulation pump is connected to the outlet of the collector, and the outlet of the second circulation pump is connected to the heat source water inlet of the evaporator.

[0015] Furthermore, it also includes: valve. When the compressor stops running, the refrigerant at the outlet of the evaporator flows through the one-way valve and then enters the condenser, exchanges heat in the condenser and then flows out, passes through the valve and the refrigerant pump in sequence, and then returns to the evaporator to absorb heat, completing the refrigerant cycle.

[0016] Furthermore, it also includes: a constant pressure water tank, which is connected to the outlet of the collector.

[0017] (III) Beneficial effects

[0018] The above technical solution of the present invention has the following beneficial technical effects:

[0019] The present invention utilizes collectors and buried pipes to store heat in the soil when there is abundant solar heat, and to supplement it with the heat stored in the soil when there is insufficient solar heat, thereby decoupling solar heat from the user's heat load demand, overcoming the impact of the intermittent nature of solar heat on the operation of the system, and effectively improving the comprehensive utilization efficiency of geothermal and solar heat. In addition, when the solar heat temperature is high and the water supply temperature of the heat user is low, the present invention utilizes a one-way valve and a refrigerant pump to achieve the cut-out of the compressor while ensuring the normal circulation of the Freon refrigerant, thereby avoiding the operating restrictions of the compressor on the heating system, improving the operating range of the system, achieving efficient and flexible adjustment of a wide range of variable operating conditions, significantly improving the operating efficiency of all operating conditions, and reducing the operating cost of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of the structure of the device of Embodiment 1 of the present invention;

[0021] Figure 2 is a schematic diagram of the device structure of embodiment 2 of the present invention;

[0022] Figure 3 is a schematic diagram of the device structure of embodiment 3 of the present invention;

[0023] Figure 4 is a schematic diagram of the structure of a device according to Embodiment 4 of the present invention;

[0024] Figure Tag:

[0025] 1: Collector; 101: Collector inlet; 102: Collector outlet; 2: Underground pipe; 201: First underground pipe interface; 202: Second underground pipe interface; 3: Evaporator; 301: Evaporator heat source water inlet; 302 Evaporator heat source water outlet; 303: Evaporator refrigerant inlet; 304: Evaporator refrigerant outlet; 4: Check valve; 401: Check valve inlet; 402: Check valve outlet; 5: Compressor; 501: Compressor inlet; 502: Compressor outlet; 6: Expansion valve; 601: Expansion valve inlet; 602: Expansion valve outlet; 7: : Refrigerant pump; 701: Refrigerant pump inlet; 702: Refrigerant pump outlet; 8: Condenser; 801: Condenser refrigerant inlet; 802: Condenser refrigerant outlet; 803: Condenser water inlet; 804: Condenser water outlet; 9: First circulation pump; 901: First circulation pump inlet; 902: First circulation pump outlet; 10: Second circulation pump; 1001: Second circulation pump inlet; 1002: Second circulation pump outlet; 11: Valve; 1101: Valve inlet; 1102: Valve outlet; 12: Constant pressure water tank; 1201: Constant pressure water tank interface. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0027] The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices.

[0028] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0029] Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. The present invention will be described in more detail below with reference to the accompanying drawings. In each of the drawings, the same elements are represented by similar figure numerals. For the sake of clarity, the various parts in the drawings are not drawn to scale.

[0030] Specifically, as described in the following specific embodiments:

[0031] Embodiment 1:

[0032] Figure 1 It is a schematic diagram of the device structure of the first embodiment of the present invention.

[0033] like Figure 1 As shown, in the invention, a soil-storage solar energy heat pump heating system comprises:

[0034] Collector 1, buried pipe 2, evaporator 3, one-way valve 4, compressor 5, expansion valve 6, refrigerant pump 7, condenser 8.

[0035] The underground pipe 2 has a first underground pipe interface 201 and a second underground pipe interface 202 .

[0036] The evaporator 3 has an evaporator heat source water inlet 301 , an evaporator heat source water outlet 302 , an evaporator refrigerant inlet 303 , and an evaporator refrigerant outlet 304 .

[0037] The condenser 8 has a condenser refrigerant inlet 801 , a condenser refrigerant outlet 802 , a condenser water inlet 803 , and a condenser water outlet 804 .

[0038] The collector outlet 102 is communicated with the evaporator heat source water inlet 301 , and the evaporator heat source water outlet 302 is communicated with the collector inlet 101 .

[0039] The evaporator heat source water outlet 302 is connected to the second interface 202 of the buried pipe.

[0040] The collector outlet 102 is connected to the first interface 201 of the buried pipe.

[0041] The evaporator refrigerant outlet 304 is connected to the compressor inlet 501 , the compressor outlet 502 is connected to the condenser refrigerant inlet 801 , the condenser refrigerant outlet 802 is connected to the expansion valve inlet 601 , and the expansion valve outlet 602 is connected to the evaporator refrigerant inlet 303 .

[0042] The evaporator refrigerant outlet 304 is connected to the one-way valve inlet 401 , the one-way valve outlet 402 is connected to the condenser refrigerant inlet 801 , the condenser refrigerant outlet 802 is connected to the refrigerant pump inlet 701 , and the refrigerant pump outlet 702 is connected to the evaporator refrigerant inlet 303 .

[0043] The condenser water inlet 803 is connected to the return water of the heat user, and the condenser water outlet 804 is connected to the supply water of the heat user.

[0044] In this embodiment, by setting up collectors and buried pipes, when the solar thermal energy is abundant, heat is stored in the soil, and when the solar thermal energy is insufficient, the heat stored in the soil is used to supplement it, thereby decoupling the solar thermal energy from the user's heat load demand, overcoming the impact of the intermittent nature of the solar thermal energy on the operation of the system, and effectively improving the comprehensive utilization efficiency of geothermal and solar thermal energy. In addition, by setting up a one-way valve and a refrigerant pump, the switching of the Freon circuit can be realized. When the solar thermal temperature is high and the water supply temperature of the heat user is low, the compressor can be cut out while ensuring the normal circulation of the Freon refrigerant, avoiding the operating restrictions of the compressor on the heating system, and improving the operating range of the system. , A wide range of variable working conditions can be achieved, and efficient and flexible adjustment can be achieved, which significantly improves the operating efficiency of all working conditions and reduces the system operating cost.

[0045] The specific operation and adjustment methods of this embodiment are as follows:

[0046] Hot user return water enters the condenser 8 through the condenser water inlet 803 , and flows out through the condenser water outlet 804 after being heated in the condenser 8 .

[0047] When the heat load of the heat user is small and the solar thermal resources are sufficient, part of the hot water flowing out of the collector outlet 102 enters the evaporator 3 through the evaporator heat source water inlet 301 for cooling, and returns to the collector 1 after cooling, while the other part of the hot water enters the buried pipe 2 through the first buried pipe interface 201, exchanges heat with the soil in the buried pipe 2 for cooling, and stores the heat in the soil, and flows out through the second buried pipe interface 202 after cooling, and returns to the collector 1, completing the heat storage process of storing the surplus solar heat in the soil.

[0048] When the heat load of the heat user is large and the light and heat resources are insufficient. Part of the cold water flowing out of the evaporator heat source water outlet 302 enters the collector through the collector inlet 101, absorbs solar energy and heats up in the collector 1, and then returns to the evaporator 3. The other part of the cold water enters the buried pipe 2 through the second interface 202 of the buried pipe, exchanges heat with the soil in the buried pipe 2 to heat up, absorbs the heat stored in the soil, flows out through the first outlet 201 of the buried pipe after heating, and returns to the evaporator 3 through the evaporator heat source water inlet 301, completing the heat release process of the heat stored in the soil.

[0049] When the water supply temperature demand of the heat user is high and the light and heat temperature is low, the refrigerant pump 7 is turned off. The refrigerant vapor flowing out of the evaporator refrigerant outlet 304 is pressurized by the compressor 5, enters the condenser 8 through the condenser refrigerant inlet 801, cools down and condenses in the condenser 8, then flows out through the condenser refrigerant outlet 802, throttles and reduces the pressure by the expansion valve 6, and returns to the evaporator 3 through the evaporator refrigerant inlet 303, absorbs heat and evaporates in the evaporator 3, and completes the refrigerant cycle.

[0050] When the water supply temperature demand of the heat user is low and the light heat temperature is high, the compressor 5 is turned off, the expansion valve 6 is turned off, and the refrigerant pump 7 is turned on. The refrigerant flowing out of the evaporator refrigerant outlet 304 passes through the one-way valve 4, enters the condenser 8 through the condenser refrigerant inlet 801, releases heat and cools down in the condenser 8, then flows out through the condenser refrigerant outlet 802, passes through the refrigerant pump 7, and returns to the evaporator 3 through the evaporator refrigerant inlet 303, absorbs heat and heats up in the evaporator 3, and completes the refrigerant cycle.

[0051] Embodiment 2:

[0052] Figure 2 It is a schematic diagram of the device structure of the second embodiment of the present invention.

[0053] The difference from the first embodiment is that the present embodiment further includes: a first circulating pump 9 and a second circulating pump 10 .

[0054] The first circulation pump inlet 901 of the first circulation pump 9 is connected to the evaporator heat source water outlet 302 , and the first circulation pump outlet 902 of the first circulation pump 9 is connected to the collector inlet 101 .

[0055] The second circulation pump inlet 1001 of the second circulation pump 10 is connected to the collector outlet 102 , and the second circulation pump outlet 1002 of the second circulation pump 10 is connected to the evaporator heat source water inlet 301 .

[0056] Compared with the first embodiment, in this embodiment, a first circulation pump 9 and a second circulation pump 10 are provided, and the frequency control of the circulation pumps is used to realize water path switching under different working conditions of heat storage and release through the soil when the light and thermal resources change, thereby improving the stability of the system operation.

[0057] Embodiment three:

[0058] Figure 3 It is a schematic diagram of the device structure of embodiment 3 of the present invention.

[0059] The difference from the second embodiment is that this embodiment further includes: a valve 11.

[0060] The valve inlet 1101 of the valve 11 is connected to the condenser refrigerant outlet 802 , and the valve outlet 1102 of the valve 11 is connected to the refrigerant pump inlet 701 .

[0061] Compared with the second embodiment, a valve 11 is added in the present embodiment. The valve 11 can be in various valve forms such as a one-way valve, an electric valve, a solenoid valve, etc. The valve 11 is linked with the refrigerant pump 7. When the refrigerant pump 7 is closed, the valve 11 is also closed, thereby shutting off the refrigerant pipeline where the refrigerant pump 7 is located, preventing the refrigerant from flowing through, and improving the stability of the system.

[0062] Embodiment 4:

[0063] Figure 4 It is a schematic diagram of the device structure of embodiment 4 of the present invention.

[0064] The difference from the first embodiment is that this embodiment further includes: a constant pressure water tank 12.

[0065] The constant pressure water tank interface 1201 of the constant pressure water tank 12 is connected to the collector outlet 102 .

[0066] Compared with the second embodiment, a constant pressure water tank 12 is added in this embodiment to ensure the stability of the water pressure, thereby ensuring the stability of the system operation.

[0067] The present invention has been described above with reference to the embodiments of the present invention. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents. Without departing from the scope of the present invention, a person skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A heat pump heating system for storing solar energy in soil, characterized in that: include: Heat collector (1), buried pipe (2), evaporator (3), one-way valve (4), compressor (5), expansion valve (6), refrigerant pump (7), condenser (8); The underground pipe (2) has an underground pipe first interface (201) and an underground pipe second interface (202); The evaporator (3) has an evaporator heat source water inlet (301), an evaporator heat source water outlet (302), an evaporator refrigerant inlet (303), and an evaporator refrigerant outlet (304); The condenser (8) has a condenser refrigerant inlet (801), a condenser refrigerant outlet (802), a condenser water inlet (803), and a condenser water outlet (804); The collector outlet (102) of the collector (1) is connected to the evaporator heat source water inlet (301) of the evaporator (3), and the evaporator heat source water outlet (302) of the evaporator (3) is connected to the collector inlet (101) of the collector (1); The evaporator heat source water outlet (302) of the evaporator (3) is connected to the underground pipe second interface (202) of the underground pipe (2); The heat collector outlet (102) of the heat collector (1) is in communication with the first underground pipe interface (201) of the underground pipe (2); The evaporator refrigerant outlet (304) of the evaporator (3) is connected to the compressor inlet (501) of the compressor (5), the compressor outlet (502) of the compressor (5) is connected to the condenser refrigerant inlet (801) of the condenser (8), the condenser refrigerant outlet (802) of the condenser (8) is connected to the expansion valve inlet (601) of the expansion valve (6), and the expansion valve outlet (602) of the expansion valve (6) is connected to the evaporator refrigerant inlet (303) of the evaporator (3); The evaporator refrigerant outlet (304) of the evaporator (3) is connected to the one-way valve inlet (401) of the one-way valve (4), the one-way valve outlet (402) of the one-way valve (4) is connected to the condenser refrigerant inlet (801) of the condenser (8), the condenser refrigerant outlet (802) of the condenser (8) is connected to the refrigerant pump inlet (701) of the refrigerant pump (7), and the refrigerant pump outlet (702) of the refrigerant pump (7) is connected to the evaporator refrigerant inlet (303) of the evaporator (3); The condenser water inlet (803) of the condenser (8) is connected to the return water of the heat user, and the condenser water outlet (804) of the condenser (8) is connected to the supply water of the heat user.

2. A soil-storage solar energy heat pump heating system as claimed in claim 1, characterized in that: Also includes: A first circulating pump (9) and a second circulating pump (10); The first circulation pump inlet (901) of the first circulation pump (9) is connected to the evaporator heat source water outlet (302) of the evaporator (3), and the first circulation pump outlet (902) of the first circulation pump (9) is connected to the collector inlet (101) of the collector (1); The second circulation pump inlet (1001) of the second circulation pump (10) is connected to the collector outlet (102) of the collector (1), and the second circulation pump outlet (1002) of the second circulation pump (10) is connected to the evaporator heat source water inlet (301) of the evaporator (3).

3. A soil-storage solar energy heat pump heating system as claimed in claim 2, characterized in that: Also includes: Valve (11); The valve inlet (1101) of the valve (11) is connected to the condenser refrigerant outlet (802) of the condenser (8), and the valve outlet (1102) of the valve (11) is connected to the refrigerant pump inlet (701) of the refrigerant pump (7).

4. A soil-storage solar energy heat pump heating system as claimed in claim 2, characterized in that: Also includes: Constant pressure water tank (12); The constant pressure water tank interface (1201) of the constant pressure water tank (12) is in communication with the collector outlet (102) of the collector (1).

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