Multi-energy coupling cooling and heating system and operation method for buildings in long-term cooling areas

Abstract

The present invention discloses a multi-energy coupling cooling and heating system and an operation method for buildings in areas with long-term cooling supply, comprising a heat source hierarchical management unit, a solar thermal collection unit, a lithium bromide absorption refrigeration unit, a gas heating supplement unit, a soil source heat pump cooling and heating unit, and an indirect evaporative cooling waste heat recovery unit; the heat source hierarchical management unit is connected to the solar thermal collection unit, the lithium bromide absorption refrigeration unit, the gas heating supplement unit, and the soil source heat pump cooling and heating unit, and the indirect evaporative cooling waste heat recovery unit is connected to the soil source heat pump cooling and heating unit; the heat storage device of the present invention adopts a double water tank mode and is designed based on the layered principle to realize hierarchical thermal management of energy of different grades, make full use of solar energy, geothermal energy, gas, waste heat and evaporative cooling energy of water, reduce system losses and improve energy utilization efficiency while meeting the building's year-round cooling, heating and domestic hot water needs.

Description

Technical Field

[0001] The present invention belongs to the field of clean application engineering of renewable energy such as solar energy and shallow geothermal energy, and in particular relates to a multi-energy coupling cooling and heating system and an operation method for buildings in areas with long-term cooling. Background Art

[0002] In southern my country, summers are hot and humid, resulting in a long cooling season and high demand for cooling in buildings. While winter temperatures aren't as low as in northern China, high humidity can cause a noticeable "cold and damp" sensation in the human body. Southern buildings experience an imbalance in cooling and heating demand year-round. Using a single energy source for both cooling and heating can lead to problems such as excessive energy consumption, severe environmental stress, and inappropriate system configuration. To address these issues, a multi-energy approach, combining the integrated use of multiple energy sources and the coordinated supply of multiple technologies, has been proposed. This approach leverages a variety of renewable and clean, low-carbon energy sources, transcending the limitations of single energy sources through multi-energy coupling and complementary utilization, thereby improving the stability of the energy supply system.

[0003] For example, an invention patent (authorization publication number: CN 110701667 B) proposes a hybrid solar energy and ground-source heat pump energy supply system and its operating method. Based on ground-source heat pump technology and thermal storage technology, this new energy supply system fully utilizes solar energy and shallow geothermal heat, adjusting the system's operating mode to meet heating needs at different temperature levels in daily life and production. However, this system can only provide heating needs for buildings, not cooling needs, making it unsuitable for residential buildings in southern China.

[0004] The invention patent (publication number CN 115127165 A) proposes a solar-coupled, ground-source heat pump-electric, dual-storage energy supply system. The ground-source heat pump serves as a supplemental heat source during the coldest winter months and a cold source for cooling in the summer. The electricity generated by the photovoltaic panels is pre-stored in batteries. A phase-change material and liquid cooling system, combined with an active-passive coupling method, collects the undesirable heat generated by the photovoltaic panels and batteries. This energy is stored in an insulated energy storage device for use in winter building heating and summer soil heating. However, this invention achieves soil heat balance by supplementing soil heat with an energy storage device, making it only suitable for buildings with a higher heat load than a cooling load. Furthermore, the system relies on batteries and phase-change material energy storage to ensure normal operation, limiting its applicability to small buildings and detached villas. The energy supply system lacks stable energy supply measures on the energy side, and excessive energy storage and storage links significantly increase the system's failure rate and operation and maintenance costs, resulting in poor economic efficiency.

[0005] The invention patent (publication number CN 115435415 A) provides a combined geothermal and air-source heating and cooling system. By leveraging the strengths of both energy sources, the system ensures stable building energy consumption. However, this system fails to account for the impact of extreme climates. In extremely cold or hot climates, the efficiency of air-source heat pumps is significantly affected by the outdoor air. In these conditions, the imbalance between heat and cold in ground-source heat pumps is also particularly pronounced. This simple combination of the two makes it difficult to guarantee user satisfaction with energy consumption.

[0006] For multi-energy coupling and complementary utilization energy supply systems, simple energy combination application will lead to low thermal efficiency and large heat loss. Thermal management of different energy sources in the system according to their grade and characteristics can effectively improve the thermal efficiency of the system and reduce For example, a patented invention (authorization publication number CN 110260396 B) proposes a solar-powered and ground-source heat pump-coupled hot water heating and cooling system based on stratified thermal management. This system utilizes the principle of temperature stratification in a hot water storage tank to control the temperature level at each node within the tank. Using a top-out and bottom-in heating method, the system achieves efficient utilization of the solar power, ground-source heat pump, and electric heating system. This system has a low load and is only suitable for household heating applications.

[0007] The aforementioned inventions are only applicable to buildings in northern China where the heating load is greater than the cooling load, and their energy supply stability is focused solely on heating. Currently, there is still a lack of ideal energy supply solutions for buildings with high cooling loads in southern regions with long-term cooling needs. Summary of the Invention

[0008] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a multi-energy coupled heating and cooling system and operation method for buildings in long-term cooling areas that can meet the heating, domestic hot water and cooling needs of buildings and can achieve stability, efficiency, comfort, energy saving and economy.

[0009] In order to achieve the above object, the system of the present invention is constituted as follows:

[0010] The multi-energy coupling cooling and heating system for buildings in long-term cooling areas of the present invention comprises a heat source hierarchical management unit, a solar heat collection unit, a lithium bromide absorption refrigeration unit, a gas heating supplement unit, a soil source heat pump cooling and heating unit, and an indirect evaporative cooling waste heat recovery unit; the heat source hierarchical management unit is connected to the solar heat collection unit, the lithium bromide absorption refrigeration unit, the gas heating supplement unit, and the soil source heat pump cooling and heating unit; the soil source heat pump cooling and heating unit is connected to the lithium bromide absorption refrigeration unit, the gas heating supplement unit, and the indirect evaporative cooling waste heat recovery unit;

[0011] The lithium bromide absorption refrigeration unit includes a first refrigeration unit heat exchanger, wherein the first shell side outlet of the first refrigeration unit heat exchanger is connected in sequence to the shell side inlet of the second refrigeration unit heat exchanger, the shell side outlet of the second refrigeration unit heat exchanger, the first throttle valve, the shell side inlet of the third refrigeration unit heat exchanger, the shell side outlet of the third refrigeration unit heat exchanger, the shell side inlet of the fourth refrigeration unit heat exchanger, the shell side outlet of the fourth refrigeration unit heat exchanger, the first solution pump and the shell side inlet of the first refrigeration unit heat exchanger through a refrigeration cycle pipeline; the second outlet of the first refrigeration unit heat exchanger is connected to the second shell side inlet of the fourth refrigeration unit heat exchanger through a return pipeline equipped with a throttle valve; wherein the first refrigeration unit heat exchanger, the second refrigeration unit heat exchanger, the third refrigeration unit heat exchanger The heat exchanger of the group and the heat exchanger of the fourth refrigeration unit are connected in series in sequence to form a ring-shaped lithium bromide absorption refrigeration unit; the outlet of the fan coil is connected to the first pipe side inlet of the soil source heat pump heat exchanger, the first pipe side outlet of the soil source heat pump heat exchanger, the tenth valve, the fifth water pump, the fourteenth valve, the sixteenth valve and the inlet of the fan coil through the fan coil heat exchange circulation pipeline; the inlet of the first connecting pipeline equipped with the ninth valve is connected to the fan coil heat exchange circulation pipeline located between the first pipe side outlet of the soil source heat pump heat exchanger and the tenth valve, and the outlet is connected to the pipe side inlet of the third refrigeration unit heat exchanger; the inlet of the second connecting pipeline is connected to the pipe side outlet of the third refrigeration unit heat exchanger, and the outlet is connected to the fan coil heat exchange circulation pipeline between the tenth valve and the fifth water pump;

[0012] The soil source heat pump cooling and heating unit includes a soil source heat pump heat exchanger second pipe side outlet, a compressor, a heat pump heat exchanger first pipe side inlet, a heat pump heat exchanger first pipe side outlet, a second throttle valve and a soil source heat pump heat exchanger second pipe side inlet, which are sequentially connected through a soil source circulation pipeline; the heat pump heat exchanger, the soil source heat pump unit compressor, the heat pump heat exchanger and the second throttle valve are connected in series to form a ring-shaped soil source heat pump unit; the second shell side outlet of the heat pump heat exchanger is sequentially connected to the sixth water pump, the seventh valve and the buried pipe heat exchanger inlet, the buried pipe heat exchanger outlet, the eighth valve and the second shell side inlet of the heat pump heat exchanger through a heat pump heat exchange circulation pipeline;

[0013] One end of the third connecting pipeline is connected to the inlet of the fresh air heat exchanger and the other end is connected to the fan coil circulation pipeline located between the fourteenth valve and the sixteenth valve. One end of the fourth connecting pipeline is connected to the outlet of the fresh air heat exchanger and the other end is connected to the fan coil heat exchange circulation pipeline located between the first pipe side inlet of the soil source heat pump heat exchanger and the outlet of the fan coil.

[0014] The gas heating unit includes a gas heating water boiler, and the heat source hierarchical management unit includes a hot water tank. The hot water outlet of the hot water tank is connected in sequence to the seventh water pump, the twelfth valve, the heating inlet of the gas hot water heating boiler, the heating outlet of the gas hot water heating boiler, the fifteenth valve, the eleventh valve and the hot water inlet of the hot water tank through a heating circulation pipeline; one end of the fifth connecting pipeline is connected to the heating circulation pipeline located between the fourteenth valve and the eleventh valve, and the other end is connected to the fan coil heat exchange circulation pipeline located between the fifteenth valve and the sixteenth valve; one end of the sixth connecting pipeline equipped with the thirteenth valve is connected to the fan coil heat exchange circulation pipeline located between the fourteenth valve and the fifth water pump, and the other end is connected to the heating circulation pipeline located between the twelfth valve and the heating inlet of the gas heating water boiler;

[0015] The indirect evaporative cooling waste heat recovery unit includes an indirect evaporative cooler and a supplementary cooling heat exchanger, wherein the wet channel outlet of the indirect evaporative cooler is connected in sequence to the inlet of the cooling side pipeline of the supplementary cooling heat exchanger, the outlet of the cooling side pipeline, the eighth water pump and the wet channel inlet of the indirect evaporative cooler through a cooling circulation pipeline; the inlet of the cooling side pipeline of the supplementary cooling heat exchanger is connected to the fan coil heat exchange circulation pipeline located between the fifth water pump and the fourteenth valve through the seventh connecting pipeline equipped with the eighteenth valve, and the outlet of the cooling side pipeline of the supplementary cooling heat exchanger is connected to the fan coil circulation pipeline located between the first pipe side inlet of the soil source heat pump heat exchanger and the outlet of the fan coil through the eighth connecting pipeline equipped with the nineteenth valve; the dry channel inlet of the indirect evaporative cooler is connected to the outdoor fresh air and the dry channel outlet is connected to the air inlet of the fresh air heat exchanger;

[0016] The heat source hierarchical management unit includes a heat collecting tank and the hot water tank; the upper circulating water outlet at the top of the heat collecting tank is connected to the second water pump, the second solenoid valve and the lower circulating water inlet at the bottom of the hot water tank in sequence through a ninth connecting pipeline; the lower circulating water outlet at the bottom of the hot water tank is connected to the first solenoid valve and the upper circulating water inlet at the top of the heat collecting tank in sequence through a tenth connecting pipeline; the outlet of the first heat extraction coil arranged in the middle of the hot water tank is connected to the domestic water terminal;

[0017] The solar thermal collection unit includes a solar thermal collector and an upper thermal collection coil located above the interior of a heat collection tank. The outlet of the solar thermal collector is connected to the inlet of the thermal collection coil. After heat exchange with the hot water stored in the heat collection tank, the outlet of the upper thermal collection coil is connected to the inlet of the solar thermal collector through a first water pump. A lower thermal collection coil is provided below the interior of the heat collection tank.

[0018] The connection structure of the lithium bromide absorption refrigeration unit and the heat source hierarchical management unit is as follows: the heat collection hot water outlet at the lower part of the heat collection tank is connected in sequence to the fourth water pump, the third valve and the pipe side inlet of the heat exchanger of the fourth refrigeration unit through an eleventh connecting pipeline; the pipe side outlet of the fourth refrigeration unit heat exchanger is connected to the pipe side inlet of the second refrigeration unit heat exchanger, the pipe side outlet of the second refrigeration unit heat exchanger, the fourth valve and the heat collection hot water inlet at the lower part of the heat collection tank; the pipe side outlet of the first refrigeration unit heat exchanger is connected in sequence to the third water pump and the inlet of the second heat extraction coil arranged at the top of the hot water extraction tank through a twelfth connecting pipeline; the outlet of the second heat extraction coil is connected to the pipe side inlet of the heat exchanger of the first refrigeration unit;

[0019] The connection between the soil source heat pump cooling and heating unit and the heat source hierarchical management unit is as follows: the outlet of the lower heat collection coil is connected to the heat pump heat exchange circulation pipeline located between the eighth valve and the second pipe side inlet of the heat pump heat exchanger through the nineteenth connecting pipeline installed with the sixth valve; the inlet of the lower heat collection coil is connected to the heat pump heat exchange circulation pipeline located between the seventh valve and the sixth water pump through the twentieth connecting pipeline installed with the fifth valve.

[0020] The present invention provides an operating method for a multi-energy coupled cooling and heating system for buildings in long-term cooling areas, including a cooling mode and a heating mode; the cooling modes include a ground source heat pump cooling mode, a ground source heat pump combined with a lithium bromide absorption refrigeration unit cooling mode, and a ground source heat pump combined with a lithium bromide absorption refrigeration unit with gas heating.

[0021] The specific control process of the ground source heat pump cooling mode is as follows:

[0022] By controlling the valves and water pumps, the connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit, lithium bromide absorption refrigeration unit, and gas heating unit is cut off; the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit and gas heating unit is cut off; the connection between the ground source heat pump cooling and heating unit and the indirect evaporative cooling waste heat recovery unit is connected, forming the ground source heat pump unit refrigeration cycle, waste heat recovery cycle, user-side chilled water cycle, and domestic hot water supply; the control process of the valves and water pumps is as follows:

[0023] Close the third valve, the fourth valve, the fifth valve, the sixth valve, the ninth valve, the eleventh valve, the twelfth valve, the thirteenth valve, and the fifteenth valve; open the first valve, the second valve, the seventh valve, the eighth valve, the tenth valve, the fourteenth valve, the sixteenth valve, the seventeenth valve, the eighteenth valve, and the nineteenth valve; start the first water pump, the second water pump, the fifth water pump, the sixth water pump, and the eighth water pump; and operate the annular ground source heat pump unit;

[0024] The control process of the combined cooling mode of the ground source heat pump and lithium bromide absorption refrigeration unit is as follows:

[0025] By controlling the valves and water pumps, the connection between the gas heating unit and the ground source heat pump cooling and heating unit and the heat source hierarchical management unit is cut off; the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected; the connection between the heat source hierarchical management unit and the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected, forming a ground source heat pump unit refrigeration cycle, a lithium bromide absorption refrigeration unit refrigeration cycle, a waste heat recovery cycle, and a user-side chilled water cycle and high-temperature hot water supply; the control of the valves and water pumps is as follows:

[0026] Close the seventh valve, the eighth valve, the tenth valve, the eleventh valve, the twelfth valve, the thirteenth valve, and the fifteenth valve; open the first valve, the second valve, the third valve, the fourth valve, the fifth valve, the sixth valve, the ninth valve, the fourteenth valve, the sixteenth valve, the seventeenth valve, the eighteenth valve, and the nineteenth valve; start the first water pump, the second water pump, the third water pump, the fourth water pump, the fifth water pump, the sixth water pump, and the eighth water pump; operate the annular ground source heat pump unit and the annular lithium bromide absorption refrigeration unit;

[0027] The combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation includes the following steps:

[0028] By controlling the water pump and valve, the connection between the gas heating unit and the ground source heat pump cooling and heating unit is cut off; the connection between the heat source hierarchical management unit and the ground source heat pump cooling and heating unit, the lithium bromide absorption refrigeration unit, and the gas heating unit is connected; the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected, forming the ground source heat pump unit refrigeration cycle, the lithium bromide absorption refrigeration unit refrigeration cycle, the waste heat recovery cycle, the user-side chilled water cycle, and the high-temperature hot water supply; the control of the water pump and valve is as follows:

[0029] Close the seventh valve, eighth valve, tenth valve, thirteenth valve and fifteenth valve, and open the first valve, second valve, third valve, fourth valve, fifth valve, sixth valve, ninth valve, eleventh valve, twelfth valve, fourteenth valve, sixteenth valve, seventeenth valve, eighteenth valve and nineteenth valve; start the first water pump, second water pump, third water pump, fourth water pump, fifth water pump, sixth water pump, seventh water pump and eighth water pump, and start the gas heating hot water boiler; operate the annular ground source heat pump unit and the annular lithium bromide absorption refrigeration unit;

[0030] The heating modes include a ground source heat pump heating mode and a gas-fired ground source heat pump heating mode. The ground source heat pump heating modes are as follows:

[0031] The soil source heat pump heating mode includes the following steps:

[0032] By controlling the valves and water pumps, the connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit, lithium bromide absorption refrigeration unit, gas heating unit, and indirect evaporative cooling waste heat recovery unit is cut off; the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit is cut off; the connection between the heat source hierarchical management unit and the gas heating unit is connected, forming the ground source heat pump unit heating cycle, the user-side heating cycle, and the domestic hot water supply. The control steps of the valves and water pumps are as follows:

[0033] Close the third valve, the fourth valve, the fifth valve, the sixth valve, the ninth valve, the thirteenth valve, the fifteenth valve, the eighteenth valve, and the nineteenth valve; open the first valve, the second valve, the seventh valve, the eighth valve, the tenth valve, the eleventh valve, the twelfth valve, the fourteenth valve, the sixteenth valve, and the seventeenth valve; start the first water pump, the second water pump, the fifth water pump, the sixth water pump, and the seventh water pump; operate the annular ground source heat pump unit and the gas heating hot water boiler;

[0034] The gas-fired ground source heat pump heating mode includes the following steps:

[0035] By controlling the water pump and valve, the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit and the indirect evaporative cooling waste heat recovery unit is cut off, and the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit and the gas heating unit is cut off. The connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit and the gas heating unit is connected, forming a ground source heat pump unit heating cycle, a user-side heating cycle, and a domestic hot water supply. The control steps of the water pump and valve are as follows:

[0036] Close the third valve, the fourth valve, the seventh valve, the eighth valve, the ninth valve, the eleventh valve, the twelfth valve, the fourteenth valve, the eighteenth valve and the nineteenth valve; open the first valve, the second valve, the fifth valve, the sixth valve, the tenth valve, the thirteenth valve, the fifteenth valve, the sixteenth valve and the seventeenth valve; start the first water pump, the second water pump, the fifth water pump and the sixth water pump; operate the annular ground source heat pump unit and the gas heating hot water boiler; the gas heating hot water boiler and the ground source heat pump unit jointly provide heat.

[0037] The beneficial effect of the present invention is that it can achieve high-quality cooling and heating for public buildings in southern my country where the summer is hot and humid and long-term cooling is required. The present invention adopts a double water tank structure, with the heat storage tank as the energy storage device. When storing heat energy, the heat storage medium will produce natural convection. Due to the density difference, high-temperature heat energy rises and low-temperature heat energy sinks, forming a stratification phenomenon. Based on the above-mentioned thermal stratification principle, the heat storage tank adopts a heat source classification management technology, which is used according to the grade of heat source, reducing Loss, realize the integrated application of multiple energy sources. In the cooling season, the ground source heat pump is used to provide cooling for users; when the cooling supply of the ground source heat pump is unstable or in extreme climates, solar energy drives the lithium bromide absorption refrigeration unit to combine with the ground source heat pump to provide cooling. At the same time, the heat release end of the lithium bromide absorption refrigeration unit and the ground source heat pump replenishes heat for the hot water storage tank where the solar collector is installed, realizing multi-energy coupling of the system and improving energy utilization efficiency. When the temperature of the hot water storage tank does not meet the starting conditions of the lithium bromide absorption refrigeration unit, the auxiliary heat source gas heating hot water boiler is started to heat the water tank, maintain the stability of the system's cooling capacity, and ensure the comfort of users. The indirect evaporative cooling waste heat recovery device provided by the present invention recovers the coldness in the indoor exhaust air of the building, and uses the evaporative cooling principle of water to realize pre-cooling and dehumidification treatment of high-temperature and high-humidity outdoor fresh air, which is energy-saving, environmentally friendly and efficient, and effectively alleviates the pressure of excessive cooling load of the system in summer. During the heating season, ground-source heat pumps are activated, supplemented by solar energy to ensure system stability. In extreme weather conditions, when combined solar and ground-source heat pumps fail to meet heating needs, gas-fired hot water boilers are activated to provide supplemental heat and maintain stable heating. Furthermore, supplemental heat from solar collectors and gas-fired hot water boilers provides year-round, all-weather domestic hot water for the building. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0039] Figure 1 This is a schematic diagram of the cooling mode structure of the multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to the present invention;

[0040] Figure 2 This is a schematic diagram of the heating mode structure of the multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to the present invention;

[0041] Figure 3 This is a schematic structural diagram of the indirect evaporative cooler according to the present invention;

[0042] Figure 4 Psychrometric diagram of the air state changes in an indirect evaporative cooler. DETAILED DESCRIPTION

[0043] The implementation of the present invention will be described in further detail below with reference to the accompanying drawings.

[0044] like Figure 1 The multi-energy coupling cooling and heating system shown for buildings in long-term cooling areas includes a heat source hierarchical management unit, a solar thermal collection unit, a lithium bromide absorption refrigeration unit, a gas heating unit, a soil source heat pump cooling and heating unit, and an indirect evaporative cooling waste heat recovery unit; the heat source hierarchical management unit is connected to the solar thermal collection unit, the lithium bromide absorption refrigeration unit, the gas heating unit, and the soil source heat pump cooling and heating unit; the soil source heat pump cooling and heating unit is connected to the lithium bromide absorption refrigeration unit, the gas heating unit, and the indirect evaporative cooling waste heat recovery unit.

[0045] The lithium bromide absorption refrigeration unit includes a first refrigeration unit heat exchanger E10. The first shell-side outlet of the first refrigeration unit heat exchanger E10 is connected in sequence through a refrigeration circulation pipeline to the shell-side inlet of the second refrigeration unit heat exchanger E11, the shell-side outlet of the second refrigeration unit heat exchanger E11, a first throttle valve E12, the shell-side inlet of the third refrigeration unit heat exchanger E13, the shell-side outlet of the third refrigeration unit heat exchanger E13, the shell-side inlet of the fourth refrigeration unit heat exchanger E14, the shell-side outlet of the fourth refrigeration unit heat exchanger E14, a first solution pump E16, and the shell-side inlet of the first refrigeration unit heat exchanger. The second outlet of the first refrigeration unit heat exchanger E10 is connected to the second shell-side inlet of the fourth refrigeration unit heat exchanger E14 through a return pipeline equipped with a throttle valve E15; the first refrigeration unit heat exchanger E10, the second refrigeration unit heat exchanger E11, the third refrigeration unit heat exchanger E13, and the fourth refrigeration unit heat exchanger E14 are connected in series in sequence to form a ring-shaped lithium bromide absorption refrigeration unit; the outlet of the fan coil E21 is connected in sequence to the first pipe-side inlet of the soil source heat pump heat exchanger E17, the first pipe-side outlet of the soil source heat pump heat exchanger E17, the tenth valve V10, the fifth water pump P5, the fourteenth valve V14, the sixteenth valve V16 and the inlet of the fan coil E21 through a fan coil heat exchange circulation pipeline. The inlet of the first connecting pipeline equipped with the ninth valve V9 is connected to the first pipe-side outlet of the ground-source heat pump heat exchanger E17 and the fan coil heat exchange circulation pipeline between the tenth valve V10, and the outlet is connected to the pipe-side inlet of the third refrigeration unit heat exchanger E13; the inlet of the second connecting pipeline is connected to the pipe-side outlet of the third refrigeration unit heat exchanger E13, and the outlet is connected to the fan coil heat exchange circulation pipeline between the tenth valve V10 and the fifth water pump P5.

[0046] The first-pass outlet of the ground-source heat pump heat exchanger E17 serves as the cooling outlet for the ground-source heat pump's heating and cooling supply. In summer, the lithium bromide refrigeration unit and the ground-source heat pump operate in tandem, sharing the building's cooling load and ensuring user cooling needs in extreme climates. This resolves the issue of unstable cooling provided by the ground-source heat pump and significantly enhances user comfort.

[0047] The soil source heat pump cooling and heating unit includes a soil source heat pump heat exchanger E17 second pipe side outlet, a compressor E18, a heat pump heat exchanger E19 first pipe side inlet, a heat pump heat exchanger E19 first pipe side outlet, a second throttle valve E20 and a soil source heat pump heat exchanger E17 second pipe side inlet which are sequentially connected through a soil source circulation pipeline; the heat pump heat exchanger E17, the soil source heat pump unit compressor E18, the heat pump heat exchanger E19, and the second throttle valve E20 are connected in series to form a ring-shaped soil source heat pump unit; the second shell side outlet of the heat pump heat exchanger E19 is sequentially connected to the sixth water pump P6, the seventh valve V7 and the inlet of the buried pipe heat exchanger E9, the outlet of the buried pipe heat exchanger E9, the eighth valve V8 and the second shell side inlet of the heat pump heat exchanger E19 through a heat pump heat exchange circulation pipeline.

[0048] One end of the third connecting pipeline is connected to the inlet of the fresh air heat exchanger E22 and the other end is connected to the fan coil circulation pipeline located between the fourteenth valve V14 and the sixteenth valve V16. One end of the fourth connecting pipeline is connected to the outlet of the fresh air heat exchanger E22 and the other end is connected to the fan coil heat exchange circulation pipeline located between the first pipe pass inlet of the soil source heat pump heat exchanger E17 and the outlet of the fan coil E21.

[0049] The gas heating unit includes a gas heating water boiler E20, and the heat source hierarchical management unit includes a hot water tank E7. The hot water outlet of the hot water tank E7 is connected in sequence to the seventh water pump P7, the twelfth valve V12, the heating inlet of the gas hot water heating boiler E20, the heating outlet of the gas hot water heating boiler E20, the fifteenth valve V15, the eleventh valve V11 and the hot water inlet of the hot water tank E7 through a heating circulation pipeline; one end of the fifth connecting pipeline is connected to the heating circulation pipeline located between the fourteenth valve V14 and the eleventh valve V11, and the other end is connected to the fan coil heat exchange circulation pipeline located between the fifteenth valve V15 and the sixteenth valve V16; one end of the sixth connecting pipeline equipped with the thirteenth valve V13 is connected to the fan coil heat exchange circulation pipeline located between the fourteenth valve V14 and the fifth water pump, and the other end is connected to the heating circulation pipeline located between the twelfth valve V12 and the heating inlet of the gas heating water boiler E20.

[0050] The indirect evaporative cooling waste heat recovery unit includes an indirect evaporative cooler E24 and a cold feed heat exchanger E23. The wet channel outlet of the indirect evaporative cooler E24 is connected sequentially via a cooling circulation pipeline to the inlet and outlet of the cold feed heat exchanger's cooling-side pipeline, the eighth water pump P8, and the wet channel inlet of the indirect evaporative cooler. The cold-side inlet of the cold feed heat exchanger is connected to the fan coil heat exchange circulation pipeline located between the fifth water pump P5 and the fourteenth valve V14 via a seventh connecting pipeline equipped with an eighteenth valve V18. The cold-side outlet of the cold feed heat exchanger is connected to the fan coil circulation pipeline located between the first pipe-pass inlet of the ground-source heat pump heat exchanger E17 and the outlet of the fan coil E21 via an eighth connecting pipeline equipped with a nineteenth valve V19. The dry channel inlet of the indirect evaporative cooler E24 is connected to the outdoor fresh air, and the dry channel outlet is connected to the air inlet of the fresh air heat exchanger E22.

[0051] The structure of the indirect evaporative cooler E24 is as follows Figure 3 As shown, the indoor exhaust air enters the wet channel of the indirect evaporative cooler E24 and comes into direct contact with the spray water. The state change process is as follows Figure 4 As shown, it is cooled and humidified from the initial state point K0 to K1, and then discharged outdoors; the high-temperature and high-humidity outdoor fresh air enters the dry channel of the indirect evaporative cooler E24, is cooled by the low-temperature air on the wet channel side, and is cooled and dehumidified from the initial state point T0 to T1. The principle of water evaporation cooling is used to achieve pre-cooling and dehumidification of the outdoor fresh air, alleviating the cooling pressure of the system in summer.

[0052] The heat source hierarchical management unit includes a heat collecting tank E6 and the heat taking tank E7; the upper circulating water outlet of the heat collecting tank E6 at the top is connected to the second water pump P2, the second solenoid valve V2 and the lower circulating water inlet at the bottom of the heat taking tank E7 in sequence through a ninth connecting pipeline; the lower circulating water outlet of the heat taking tank E7 at the bottom is connected to the first solenoid valve V1 and the upper circulating water inlet at the top of the heat collecting tank E6 in sequence through a tenth connecting pipeline; the outlet of the first heat extraction coil E4 arranged in the middle of the heat taking tank E7 is connected to the domestic water terminal E3 to meet the user's domestic hot water needs throughout the year.

[0053] The solar thermal collection unit includes a solar thermal collector E1 and an upper thermal collection coil E2 located above the interior of the heat collection tank E6. The outlet of the solar thermal collector E1 is connected to the inlet of the upper thermal collection coil E2. After heat exchange with the stored water in the heat collection tank E6, the outlet of the thermal collection coil E2 is connected to the inlet of the solar thermal collector E1 through a first water pump P1. A lower thermal collection coil E25 is provided below the interior of the heat collection tank E6.

[0054] The connection structure of the lithium bromide absorption refrigeration unit and the heat source hierarchical management unit is as follows: the heat collection hot water outlet at the bottom of the heat collection tank E6 is connected in sequence to the fourth water pump P4, the third valve V3 and the pipe side inlet of the fourth refrigeration unit heat exchanger E14 through the eleventh connecting pipeline; the pipe side outlet of the fourth refrigeration unit heat exchanger E14 is connected to the pipe side inlet of the second refrigeration unit heat exchanger E11, the pipe side outlet of the second refrigeration unit heat exchanger E11, the fourth valve V4 and the heat collection hot water inlet at the bottom of the heat collection tank E6; the pipe side outlet of the first refrigeration unit heat exchanger E10 is connected in sequence to the third water pump P3 and the inlet of the second heat extraction coil E8 arranged at the top of the hot water tank E7 through the twelfth connecting pipeline; the outlet of the second heat extraction coil E8 is connected to the pipe side inlet of the first refrigeration unit heat exchanger E10.

[0055] The connection between the soil source heat pump cooling and heating unit and the heat source hierarchical management unit is as follows: the outlet of the lower heat collection coil E25 is connected to the heat pump heat exchange circulation pipeline located between the eighth valve and the second pipe side inlet of the heat pump heat exchanger E19 through the nineteenth connecting pipeline installed with the sixth valve V6; the inlet of the lower heat collection coil E25 is connected to the heat pump heat exchange circulation pipeline located between the seventh valve V7 and the sixth water pump P6 through the twentieth connecting pipeline installed with the fifth valve V5.

[0056] The heat source hierarchical management unit is based on the temperature stratification principle of the heat storage tank, and designs the water level nodes of the heat collection tank E6 and the heat extraction tank E7 according to the quality of different heat sources; the node positions designed for the heat collection tank E6 are as follows from top to bottom: the circulating water inlet and outlet at the top, the upper heat collection coil E2 of the solar heat collection unit at the top, the heat collection hot water inlet and outlet connected to the lithium bromide absorption refrigeration unit at the bottom, and the lower heat collection coil E25 connected to the ground source heat pump cooling and heating unit at the bottom; the heat extraction The nodes designed for water tank E7 are, from top to bottom, the second heat extraction coil E8 at the top, the hot water outlet and inlet connected to the gas-fired heat extraction unit at the top; the first heat extraction coil E4 in the middle, and the circulating water outlet and inlet connected to the heat collection tank E6 at the bottom. During the cooling season, heat energy is transferred between the heat collection tank E6 and the hot water extraction tank E7 by driving the second water pump P2. The high-quality heat energy in the heat collection tank E6 is concentrated in the hot water extraction tank E7 to provide high-temperature heat energy for the lithium bromide absorption refrigeration unit.

[0057] As shown in the accompanying drawings, the operating method of the multi-energy coupled cooling and heating system for buildings in long-term cooling areas includes a cooling mode and a heating mode; the cooling modes include a ground source heat pump cooling mode, a ground source heat pump and a lithium bromide absorption refrigeration unit combined cooling mode, and a ground source heat pump and a lithium bromide absorption refrigeration unit with gas heating.

[0058] The specific control process of the ground source heat pump cooling mode is as follows:

[0059] By controlling valves and water pumps, the connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit, lithium bromide absorption refrigeration unit, and gas heating unit is cut off; the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit and gas heating unit is cut off; the connection between the ground source heat pump cooling and heating unit and the indirect evaporative cooling waste heat recovery unit is connected, forming the ground source heat pump unit refrigeration cycle, waste heat recovery cycle, user-side chilled water cycle, and domestic hot water supply; the control process of valves and water pumps is as follows:

[0060] Close the third valve V3, the fourth valve V4, the fifth valve V5, the sixth valve V6, the ninth valve V9, the eleventh valve V11, the twelfth valve V12, the thirteenth valve V13, and the fifteenth valve V15; open the first valve V1, the second valve V2, the seventh valve V7, the eighth valve V8, the tenth valve V10, the fourteenth valve V14, the sixteenth valve V16, the seventeenth valve V17, the eighteenth valve V18, and the nineteenth valve V19; start the first water pump P1, the second water pump P2, the fifth water pump P5, the sixth water pump P6, and the eighth water pump P8; operate the annular ground source heat pump unit; and only utilize the cold energy stored in the soil and the natural cold energy from the phase change and evaporation of water to meet the cooling load demand of the building.

[0061] The refrigeration cycle of the soil source heat pump unit includes the following steps:

[0062] The compressor E18 of the ground-source heat pump unit compresses the low-temperature gaseous refrigerant into a high-temperature gaseous refrigerant. The compressed refrigerant flows into the heat pump heat exchanger E19, exchanges heat with the circulating water return from the ground heat exchanger E9, and is cooled and liquefied into liquid refrigerant. The refrigerant then flows into the throttle valve E20. After being throttled by the throttle valve E20, the liquid refrigerant expands into a gas-liquid two-phase mixed refrigerant. The gas-liquid two-phase mixed refrigerant enters the heat pump heat exchanger E17, absorbs heat from the user-side cooling circulation return water in the heat pump heat exchanger E17, and its temperature rises. The gas-liquid two-phase mixed refrigerant becomes superheated refrigerant vapor. The superheated refrigerant vapor finally returns to the compressor E18 of the ground-source heat pump unit, thus completing the refrigeration cycle of the ground-source heat pump unit.

[0063] The waste heat recovery cycle includes the following steps (the internal structure of the indirect evaporative cooler is as follows Figure 3 shown):

[0064] The cooling water flows out of the wet channel outlet of the indirect evaporative cooler E24 and enters the supplementary cold heat exchanger E23, where it exchanges heat with the chilled water in the cold side pipeline of the supplementary cold heat exchanger E23 to reduce its temperature. The cooled cooling water enters the wet channel of the indirect evaporative cooler E24 under the pressure of the eighth water pump P8, where it directly exchanges heat and moisture with the indoor exhaust air in the wet channel, and indirectly exchanges heat with the outdoor fresh air in the dry channel on the other side (see the air state change). Figure 4 Then it flows out from the wet channel outlet of the indirect evaporative cooler and returns to the supplementary cooling heat exchanger E23, thus completing the waste heat recovery cycle.

[0065] The user-side chilled water cycle includes the following steps:

[0066] The chilled water returning from the cold feed heat exchanger E23, fan coil unit E21, and fresh air heat exchanger E22 enters the first tube side of the heat pump heat exchanger E17 to exchange heat with the gas-liquid two-phase mixed refrigerant in the second tube side of the heat pump heat exchanger for cooling. The chilled water then flows out of the outlet of the first tube side of the heat pump heat exchanger E17 and, under the pressure of the fifth water pump P5, returns to the user-side fan coil unit E21, fresh air heat exchanger E22, and cold feed heat exchanger E23, thus completing the user-side chilled water cycle.

[0067] The domestic hot water supply comprises the following steps:

[0068] The high-temperature refrigerant in solar thermal collector E1 enters the upper heat collection coil E2, where it exchanges heat with the hot water in the upper portion of heat collection tank E6, cooling it down before returning to solar thermal collector E1 under the pressure of water pump P1. The hot water in the heat collection tank is heated by the heat collection coil. Driven by the second water pump P2, the high-temperature hot water at the top of heat collection tank E6 flows through the lower circulating water inlet of hot water extraction tank E7 and into the bottom of hot water extraction tank E7. The low-temperature hot water at the bottom of hot water extraction tank E6 flows through the lower circulating water outlet and into the top of hot water extraction tank E6, transferring high-quality thermal energy from hot water extraction tank E6 to hot water extraction tank E7. Domestic tap water enters the first heat extraction coil E4, where it heats up with the hot water in the middle of hot water extraction tank E7. The heated tap water is then delivered to users, meeting their domestic hot water needs.

[0069] The control process of the combined cooling mode of the ground source heat pump and lithium bromide absorption refrigeration unit is as follows:

[0070] By controlling the valves and water pumps, the connection between the gas heating unit and the ground source heat pump cooling and heating unit and the heat source hierarchical management unit is cut off; the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected; the connection between the heat source hierarchical management unit and the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected, forming a ground source heat pump unit refrigeration cycle, a lithium bromide absorption refrigeration unit refrigeration cycle, a waste heat recovery cycle, and a user-side chilled water cycle and high-temperature hot water supply; the control of the valves and water pumps is as follows:

[0071] Close the seventh valve V7, the eighth valve V8, the tenth valve V10, the eleventh valve V11, the twelfth valve V12, the thirteenth valve V13 and the fifteenth valve V15; open the first valve V1, the second valve V2, the third valve V3, the fourth valve V4, the fifth valve V5, the sixth valve V6, the ninth valve V9, the fourteenth valve V14, the sixteenth valve V16, the seventeenth valve V17, the eighteenth valve V18 and the nineteenth valve V19; start the first water pump P1, the second water pump P2, the third water pump P3, the fourth water pump P4, the fifth water pump P5, the sixth water pump P6 and the eighth water pump P8; operate the annular ground source heat pump unit and the annular lithium bromide absorption refrigeration unit; the annular lithium bromide absorption refrigeration unit is driven by the solar energy coupled ground source heat pump and its own heat release.

[0072] The refrigeration cycle of the soil source heat pump unit includes the following steps:

[0073] The soil-source heat pump unit compressor E18 compresses low-temperature refrigerant vapor into high-temperature refrigerant vapor. The compressed refrigerant flows into the heat pump heat exchanger E19, exchanges heat with the circulating water return from the lower heat collecting coil E25, and is cooled and liquefied into liquid refrigerant. The refrigerant then flows into the throttle valve E20. After throttling by the throttle valve E20, the liquid refrigerant expands into a gas-liquid two-phase mixed refrigerant. The gas-liquid two-phase mixed refrigerant enters the second pipe side of the heat pump heat exchanger E17. In the heat pump heat exchanger E17, the heat is exchanged with the user-side cooling circulation return water in the first pipe side, and the temperature of the gas-liquid two-phase mixed refrigerant is increased. The superheated refrigerant vapor finally returns to the soil-source heat pump unit compressor E18, thus completing the refrigeration cycle of the soil-source heat pump unit.

[0074] The refrigeration cycle of the lithium bromide absorption refrigeration unit comprises the following steps:

[0075] The refrigerant vapor flowing out of the third refrigeration unit heat exchanger E13 enters the fourth refrigeration unit heat exchanger E14. The concentrated lithium bromide solution in the fourth refrigeration unit heat exchanger E14 absorbs the refrigerant vapor from the third refrigeration unit heat exchanger E13, and the concentrated lithium bromide solution is diluted to a dilute lithium bromide solution. The heat released in this absorption process is carried away by the low-temperature circulating water from the heat collection tank E6 in the pipe side. The dilute lithium bromide solution enters the first refrigeration unit heat exchanger E10 under the boosted pressure of the first solution pump E16. The dilute lithium bromide solution is heated in the shell side of the first refrigeration unit heat exchanger E10 by the circulating hot water from the second heat extraction coil E8 in the heat exchanger pipe side. In this process, the refrigerant in the dilute lithium bromide solution evaporates into refrigerant vapor and enters the second refrigeration unit heat exchanger E11. The dilute lithium bromide solution in the first refrigeration unit heat exchanger E10 is heated in the shell side of the first refrigeration unit heat exchanger E10 by the circulating hot water from the second heat extraction coil E8 in the heat exchanger pipe side. The liquid is heated and concentrated into a concentrated lithium bromide solution, which is then depressurized and throttled by the throttle valve E15 and returned to the fourth refrigeration unit heat exchanger E14. The refrigerant vapor from the first refrigeration unit heat exchanger E10 is cooled and liquefied into liquid refrigerant in the shell side of the second refrigeration unit heat exchanger E11 by the low-temperature circulating water in the heat exchanger tube side from the outlet of the fourth refrigeration unit heat exchanger E14. The refrigerant then flows out of the second refrigeration unit heat exchanger E11, is depressurized and throttled by the first throttle valve E12 to become liquid refrigerant, and then enters the third refrigeration unit heat exchanger E13. The liquid refrigerant in the third refrigeration unit heat exchanger E13 absorbs heat from the circulating chilled water in the heat exchanger tube side in the shell side of the third refrigeration unit heat exchanger E13, thereby evaporating and gasifying into refrigerant vapor. The refrigerant then returns to the fourth refrigeration unit heat exchanger E14, completing the lithium bromide refrigeration cycle of the refrigeration unit.

[0076] The waste heat recovery cycle steps in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit adopt the same steps as the waste heat recovery cycle in the cooling mode of the soil source heat pump;

[0077] The user-side chilled water cycle includes the following steps:

[0078] The chilled water returning from the cold feed heat exchanger E23, fan coil unit E21, and fresh air heat exchanger E22, which has a temperature exceeding 12°C, enters the first tube pass of the heat pump heat exchanger E17 for heat exchange and cooling. The cooled chilled water then flows from the heat pump heat exchanger E17 through the second connecting pipeline into the third refrigeration unit heat exchanger E13. The chilled water is cooled to approximately 7°C in the tube pass of the third refrigeration unit heat exchanger E13 by the refrigerant in the shell pass of the heat exchanger. The chilled water then enters the fan coil unit heat exchange circulation pipeline under pressure from the fifth water pump P5 and returns to the user-side fan coil unit E21, fresh air heat exchanger E22, and cold feed heat exchanger E23, completing the user-side chilled water circulation.

[0079] The high-temperature hot water supply comprises the following steps:

[0080] The high-temperature refrigerant from the solar thermal collector E1 enters the upper heat collecting coil E2 and exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, and then cools down. It returns to the solar thermal collector E1 under the pressure of the first water pump P1; the hot water stored in the upper part of the heat collecting tank E6 is heated by the upper heat collecting coil E2; the hot water stored in the lower part of the heat collecting tank E6 enters the pipe side of the fourth refrigeration unit heat exchanger E14 under the promotion of the fourth water pump P4, and reacts with the lithium bromide solution in the shell side of the heat exchanger of the fourth refrigeration unit. The heated circulating water flows out of the fourth refrigeration unit heat exchanger E14 and enters the tube side of the second refrigeration unit heat exchanger E11, where it is heated to 50-70°C by the refrigerant in the shell side of the second refrigeration unit heat exchanger. The circulating water then returns to the heat collecting tank E6. The low-temperature circulating water after heat exchange in the lower heat collecting coil E25 at the bottom of the heat collecting tank E6 enters the second tube side of the heat pump heat exchanger E19 and exchanges heat with the gaseous refrigerant in the first tube side of the heat pump heat exchanger E19. The water is heated and returned to the lower heat collecting coil E25 under the pressure of the sixth water pump P6. Under the promotion of the second water pump P2, the high-temperature stored water at the top of the heat collecting tank E6 enters the hot water taking tank E7 through the lower circulating water inlet of the hot water taking tank E7. The low-temperature stored water at the bottom of the hot water taking tank E7 enters the top of the heat collecting tank E6 through the lower circulating water outlet, thus transferring the high-quality heat energy from the hot water collecting tank E6 to the hot water taking tank E7. Domestic tap water enters the first heat taking coil E4, exchanges heat with the stored water in the middle of the hot water taking tank E7, and is heated and supplied to users, meeting their domestic hot water needs. The high-temperature hot water in the second heat taking coil E8 at the top of the hot water taking tank E7 enters the tube side of the first refrigeration unit heat exchanger E10, exchanges heat with the lithium bromide solution in the shell side to reduce its temperature, providing high-quality heat energy for the lithium bromide absorption refrigeration unit. The circulating water, which has exchanged heat, returns to the second heat taking coil E8 under the promotion of the third water pump P3, completing the high-temperature hot water supply.

[0081] The combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation includes the following steps:

[0082] By controlling the water pump and valve, the connection between the gas heating unit and the ground source heat pump cooling and heating unit is cut off; the connection between the heat source hierarchical management unit and the ground source heat pump cooling and heating unit, the lithium bromide absorption refrigeration unit, and the gas heating unit is connected; the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected, forming the ground source heat pump unit refrigeration cycle, the lithium bromide absorption refrigeration unit refrigeration cycle, the waste heat recovery cycle, the user-side chilled water cycle, and the high-temperature hot water supply; the control of the water pump and valve is as follows:

[0083] Close the seventh valve V7, the eighth valve V8, the tenth valve V10, the thirteenth valve V13, and the fifteenth valve V15; open the first valve V1, the second valve V2, the third valve V3, the fourth valve V4, the fifth valve V5, the sixth valve V6, the ninth valve V9, the eleventh valve V11, the twelfth valve V12, the fourteenth valve V14, the sixteenth valve V16, the seventeenth valve V17, the eighteenth valve V18, and the nineteenth valve V19; start the first water pump P1, the second water pump P2, the third water pump P3, the fourth water pump P4, the fifth water pump P5, the sixth water pump P6, the seventh water pump P7, and the eighth water pump P8; start the gas heating hot water boiler E20; operate the annular ground source heat pump unit and the annular lithium bromide absorption refrigeration unit; the lithium bromide absorption refrigeration unit is driven by solar energy coupled with gas, the ground source heat pump, and its own heat release.

[0084] The refrigeration cycle steps of the soil source heat pump unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplement adopt the same steps as the refrigeration cycle steps of the soil source heat pump unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit;

[0085] The refrigeration cycle steps of the lithium bromide absorption refrigeration unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplement adopt the same steps as the refrigeration cycle steps of the lithium bromide absorption refrigeration unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit;

[0086] The waste heat recovery cycle steps in the combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation adopt the same steps as the waste heat recovery cycle in the ground source heat pump cooling mode;

[0087] The user-side chilled water circulation steps in the combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation adopt the same steps as the user-side chilled water circulation steps in the ground source heat pump cooling mode;

[0088] The high-temperature hot water supply adopts the following steps:

[0089] The high-temperature refrigerant in the solar thermal collector E1 enters the upper heat collecting coil E2 and exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, where it is cooled down and then returns to the solar thermal collector E1 under the pressure of the water pump P1. The hot water stored in the heat collecting tank E6 is heated by the upper heat collecting coil E2. The hot water stored in the lower part of the heat collecting tank E6 enters the tube side of the fourth refrigeration unit heat exchanger E14 under the push of the fourth water pump P4, exchanges heat with the lithium bromide solution in the shell side of the fourth refrigeration unit heat exchanger, and its temperature rises. It then enters the heat exchanger of the fourth refrigeration unit and is heated. The circulating water flows out of the fourth refrigeration unit heat exchanger E14 and enters the pipe side of the second refrigeration unit heat exchanger E11, and is reheated by the gaseous refrigerant in the shell side of the second refrigeration unit heat exchanger. The circulating water reheated in the shell side of the second refrigeration unit heat exchanger returns to the heat collecting tank E6; the low-temperature circulating water in the lower heat collecting coil E25 at the bottom of the heat collecting tank E6 enters the second pipe side of the heat pump heat exchanger E19, exchanges heat with the gaseous refrigerant in the first pipe side of the heat pump heat exchanger, and then returns to the heat collecting tank E6 under the pressure of the sixth water pump P6. The hot water in the upper part of the hot water tank E7 is pressurized by the seventh water pump P7 and enters the gas heating water boiler E20 through the heat supply circulation pipeline. The circulating water heated by the flue gas returns to the hot water tank E7. Domestic tap water enters the first heat extraction coil E4, exchanges heat with the stored water in the middle of the hot water tank E7, and is then delivered to users to meet their domestic hot water needs. The high-temperature hot water in the second heat extraction coil E8 at the top of the hot water tank E7 enters the first refrigeration unit heat exchanger E10, providing high-quality thermal energy for the first refrigeration unit heat exchanger. The heat-exchanged circulating water is driven by the third water pump P3 and returns to the first heat collection coil E8, completing the high-temperature hot water supply.

[0090] The heating modes include a ground source heat pump heating mode and a gas-fired ground source heat pump heating mode. The ground source heat pump heating modes are as follows:

[0091] The soil source heat pump heating mode includes the following steps:

[0092] By controlling valves and water pumps, the connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit, lithium bromide absorption refrigeration unit, gas heating unit, and indirect evaporative cooling waste heat recovery unit is cut off; the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit is cut off; the connection between the heat source hierarchical management unit and the gas heating unit is connected, forming the ground source heat pump unit heating cycle, the user-side heating cycle, and the domestic hot water supply; the control steps of the valves and water pumps are as follows:

[0093] Close the third valve V3, the fourth valve V4, the fifth valve V5, the sixth valve V6, the ninth valve V9, the thirteenth valve V13, the fifteenth valve V15, the eighteenth valve V18, and the nineteenth valve V19; open the first valve V1, the second valve V2, the seventh valve V7, the eighth valve V8, the tenth valve V10, the eleventh valve V11, the twelfth valve V12, the fourteenth valve V14, the sixteenth valve V16, and the seventeenth valve V17; start the first water pump P1, the second water pump P2, the fifth water pump P5, the sixth water pump P6, and the seventh water pump P7; operate the annular ground source heat pump unit and the gas heating water heater E20; in winter, the heat stored in the soil is used to heat the building, and solar energy and gas are combined to meet the users' domestic hot water needs.

[0094] The heating cycle of the soil source heat pump unit includes the following steps:

[0095] The ground-source heat pump compressor E18 compresses the low-temperature gaseous refrigerant to increase its temperature. The compressed refrigerant flows into the second pipe side of the heat pump heat exchanger E17, exchanges heat with the hot water return water from the user-side fan coil unit E21 and the fresh air heat exchanger E22 in the first pipe side of the heat pump heat exchanger, and is then cooled and liquefied into liquid refrigerant. The refrigerant then flows into the throttle valve E20. After being throttled by the throttle valve E20, the liquid refrigerant expands to become a gas-liquid two-phase mixed refrigerant. The gas-liquid two-phase mixed refrigerant enters the first pipe side of the heat pump heat exchanger E19, where it absorbs heat from the circulating return water from the ground-source heat exchanger E9 in the second pipe side of the heat pump heat exchanger, raising its temperature. The gas-liquid two-phase mixed refrigerant is then heated to become superheated refrigerant vapor and returns to the ground-source heat pump compressor E18, thus completing the heating cycle of the ground-source heat pump unit.

[0096] The user-side heating cycle includes the following steps:

[0097] Hot water return from the user-side fan coil unit E21 and fresh air heat exchanger E22 enters the first tube side of the heat pump heat exchanger E17, where it exchanges heat with the gaseous refrigerant in the second tube side of the heat pump heat exchanger to increase its temperature. Hot water flows out of the first tube side of the heat pump heat exchanger E17 and, under the pressure of the fifth water pump P5, passes through the fan coil heat exchange pipeline and enters the user-side fan coil unit E21 and fresh air heat exchanger E22 for heat exchange. It then returns to the first tube side of the heat pump heat exchanger E17, completing the user-side heating cycle.

[0098] The domestic hot water supply comprises the following steps:

[0099] The high-temperature refrigerant in the solar thermal collector E1 enters the upper heat collecting coil E2, exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, and then cools down. It is then returned to the solar thermal collector E1 under the pressure of the first water pump P1. The hot water stored in the heat collecting tank E6 is heated by the upper heat collecting coil E2. The high-temperature hot water stored at the top of the heat collecting tank E6 is driven by the second water pump P2 to enter the bottom of the hot water tank E7. The low-temperature hot water stored at the bottom of the hot water tank E7 enters the top of the heat collecting tank E6 through the lower circulating water outlet, thus transferring the high-quality heat energy from the heat collecting tank E6 to the hot water tank E7. The circulating water located in the upper part of the hot water tank E7 enters the gas-fired heating water boiler E20 under the pressure of the seventh water pump P7. The circulating water heated by heat exchange with the high-temperature flue gas in the gas-fired heating water boiler E20 returns to the hot water tank E7. The domestic tap water enters the first heat extracting coil E4, exchanges heat with the hot water stored in the middle of the hot water tank E7, and is then delivered to the user to meet the user's domestic hot water demand. In this way, the domestic hot water supply is completed.

[0100] The gas-fired ground source heat pump heating mode includes the following steps:

[0101] By controlling the water pump and valve, the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit and the indirect evaporative cooling waste heat recovery unit is cut off, and the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit and the gas heating unit is cut off. The connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit and the gas heating unit is connected, forming a ground source heat pump unit heating cycle, a user-side heating cycle, and a domestic hot water supply. The control steps of the water pump and valve are as follows:

[0102] Close the third valve V3, the fourth valve V4, the seventh valve V7, the eighth valve V8, the ninth valve V9, the eleventh valve V11, the twelfth valve V12, the fourteenth valve V14, the eighteenth valve V18, and the nineteenth valve V19; open the first valve V1, the second valve V2, the fifth valve V5, the sixth valve V6, the tenth valve V10, the thirteenth valve V13, the fifteenth valve V15, the sixteenth valve V16, and the seventeenth valve V17; start the first water pump P1, the second water pump P2, the fifth water pump P5, and the sixth water pump P6; operate the annular ground source heat pump unit and the gas heating water heater E20; the gas heating water heater E20 and the ground source heat pump unit jointly provide heat to ensure stable system heating and meet user comfort requirements.

[0103] The heating cycle steps of the ground source heat pump unit in the gas-heating supplementary ground source heat pump heating mode are the same as those of the ground source heat pump unit in the ground source heat pump heating mode;

[0104] The user-side heating cycle includes the following steps:

[0105] The hot water return from the user-side fan coil unit E21 and fresh air heat exchanger E22 enters the first tube pass of the heat pump heat exchanger E17, where it exchanges heat with the gaseous refrigerant in the second tube pass of the heat pump heat exchanger to increase its temperature. The heated hot water flows out of the first tube pass of the heat pump heat exchanger E17 and, under the pressure of the fifth water pump P5, enters the gas-fired hot water boiler E20 through the supplementary heat circulation pipeline to exchange heat with the high-temperature flue gas for further heating. The heated hot water, now heated to over 45°C, flows out of the gas-fired hot water boiler E20, enters the user-side fan coil unit E21 and fresh air heat exchanger E22 for heat exchange, and then returns to the first tube pass of the heat pump heat exchanger E17, thus completing the user-side heating cycle.

[0106] The domestic hot water supply comprises the following steps:

[0107] The high-temperature refrigerant in the solar thermal collector E1 enters the upper heat collecting coil E2, exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, and then cools down. It then returns to the solar thermal collector E1 under the pressure of the first water pump P1; the hot water stored in the heat collecting tank is heated by the upper heat collecting coil E2; the high-temperature hot water stored at the top of the heat collecting tank E6 is pushed by the second water pump P2 to the bottom of the hot water extraction tank E7, and the low-temperature hot water stored at the bottom of the hot water extraction tank E7 enters the top of the heat collecting tank E6 through the lower circulating water outlet, realizing the transfer of high-quality thermal energy from the heat collecting tank E6 to the hot water extraction tank E7; domestic tap water enters the first heat extraction coil E4, exchanges heat with the hot water stored in the middle of the hot water extraction tank E7, and is heated and supplied to users to meet their domestic hot water needs; thus, domestic hot water supply is completed.

[0108] Example

[0109] The refrigeration cycle of the soil source heat pump unit includes the following steps:

[0110] The soil source heat pump unit compressor E18 compresses the gaseous refrigerant at -10 to 10°C (e.g., -10°C, 5°C, 10°C) into a gaseous refrigerant at 55 to 75°C (e.g., 55°C, 60°C, 75°C). The compressed refrigerant flows into the heat pump heat exchanger E19, exchanges heat with the circulating water return from the soil heat exchanger E9, and then cools down and liquefies into a liquid refrigerant at 40 to 55°C (e.g., 40°C, 45°C, 55°C). The liquid refrigerant then flows into the throttle valve E20. After being throttled by the throttle valve E20, the liquid refrigerant is throttled. The gas-liquid two-phase mixed refrigerant expands to a temperature of -15 to 5°C (e.g., -15°C, 0°C, 5°C). The gas-liquid two-phase mixed refrigerant enters the heat pump heat exchanger E17. After absorbing heat from the return water of the user-side cooling cycle in the heat pump heat exchanger E17, the temperature of the gas-liquid two-phase mixed refrigerant rises. The gas-liquid two-phase mixed refrigerant becomes a superheated refrigerant vapor at a temperature of -10 to 10°C (e.g., -10°C, 5°C, 10°C). The superheated refrigerant vapor finally returns to the compressor E18 of the ground source heat pump unit, thus completing the refrigeration cycle of the ground source heat pump unit.

[0111] The waste heat recovery cycle includes the following steps (the internal structure of the indirect evaporative cooler is as follows Figure 3 shown):

[0112] The cooling water at 20-22°C (e.g., 20°C, 21°C, 22°C) flowing out of the wet channel outlet of the indirect evaporative cooler E24 enters the supplementary cold heat exchanger E23, and exchanges heat with the chilled water in the cold side pipeline of the supplementary cold heat exchanger E23 to reduce its temperature to 16-18°C (e.g., 16°C, 17°C, 18°C). The cooled cooling water enters the wet channel of the indirect evaporative cooler E24 under the pressure of the eighth water pump P8, and is cooled by the cooling water in the wet channel. The indoor exhaust air of the building with a relative humidity of 30-50% (such as 30%, 40%, 50%) and a temperature of 24-26℃ (such as 24℃, 25℃, 26℃) directly exchanges heat and moisture, and indirectly exchanges heat with the outdoor fresh air in the dry channel on the other side with a relative humidity of 60-90% (such as 60%, 80%, 90%) and a temperature of 30-38℃ (such as 30℃, 35℃, 38℃) (see the air state change). Figure 4 Then it flows out from the wet channel outlet of the indirect evaporative cooler and returns to the supplementary cooling heat exchanger E23, thus completing the waste heat recovery cycle.

[0113] The user-side chilled water cycle includes the following steps:

[0114] The chilled water at approximately 12°C flowing out of the supplemental cooling heat exchanger E23, fan coil unit E21, and fresh air heat exchanger E22 enters the first tube side of the heat pump heat exchanger E17 to exchange heat with the gas-liquid two-phase mixed refrigerant in the second tube side of the heat pump heat exchanger for cooling. The chilled water at approximately 7°C flowing out of the outlet of the first tube side of the heat pump heat exchanger E17 is pressurized by the fifth water pump P5 and then returns to the user-side fan coil unit E21, fresh air heat exchanger E22, and supplemental cooling heat exchanger E23, thus completing the user-side chilled water cycle.

[0115] The domestic hot water supply comprises the following steps:

[0116] The high-temperature refrigerant at 80-120°C (e.g., 80°C, 100°C, 120°C) in the solar collector E1 enters the upper heat collection coil E2 and exchanges heat with the stored water in the upper part of the heat collection tank E6, where it is cooled to 60-70°C (e.g., 60°C, 65°C, 70°C) and then returns to the solar collector E1 under the pressure of the water pump P1. The hot water in the heat collecting tank is heated by the heat collecting coil. The high-temperature hot water at the top of the heat collecting tank E6, with a temperature between 60°C and 90°C (e.g., 60°C, 80°C, and 90°C), is pumped by the second water pump P2 and enters the bottom of the hot water tank E7 through the lower circulating water inlet of the hot water tank E7. The low-temperature hot water at the bottom of the hot water tank E6, with a temperature below 50°C, enters the top of the heat collecting tank E6 through the lower circulating water outlet, thereby transferring high-quality thermal energy from the heat collecting tank E6 to the hot water tank E7. Domestic tap water enters the first heat extraction coil E4, where it heat-exchanges with the hot water in the middle of the hot water tank E7 to increase its temperature. The heated tap water, at a temperature between 50°C and 60°C (e.g., 50°C, 55°C, and 60°C), is delivered to users, meeting their domestic hot water needs.

[0117] The refrigeration cycle of the soil source heat pump unit includes the following steps:

[0118] The soil source heat pump unit compressor E18 compresses the refrigerant vapor at -10 to 10°C (e.g., -10°C, 5°C, 10°C) into refrigerant vapor at 55 to 75°C (e.g., 55°C, 70°C, 75°C). The compressed refrigerant flows into the heat pump heat exchanger E19, exchanges heat with the circulating water return from the lower heat collecting coil E25, and then cools down and liquefies into liquid refrigerant at 40 to 55°C (e.g., 40°C, 45°C, 55°C). The liquid refrigerant then flows into the throttle valve E20, and expands after throttling by the throttle valve E20 to become -1 The gas-liquid two-phase mixed refrigerant at a temperature of 5 to 5°C (e.g., -15°C, -10°C, 5°C) enters the second pipe side of the heat pump heat exchanger E17. After heat exchange with the return water from the user-side cooling cycle in the first pipe side of the heat pump heat exchanger E17, the temperature of the gas-liquid two-phase mixed refrigerant rises. The gas-liquid two-phase mixed refrigerant becomes superheated refrigerant vapor at a temperature of -10 to 10°C (e.g., -10°C, 6°C, 10°C). The superheated refrigerant vapor finally returns to the compressor E18 of the ground source heat pump unit, thus completing the refrigeration cycle of the ground source heat pump unit.

[0119] The refrigeration cycle of the lithium bromide absorption refrigeration unit comprises the following steps:

[0120] The refrigerant vapor flowing out of the third refrigeration unit heat exchanger E13 with a temperature of 2-5°C (e.g., 2°C, 4°C, 5°C) and an absolute pressure of 0.8-0.9 kPa (e.g., 0.8 kPa, 0.85 kPa, 0.9 kPa) enters the fourth refrigeration unit heat exchanger E14. The concentrated lithium bromide solution with a mass percentage of 58-64% (e.g., 58%, 60%, 64%) in the fourth refrigeration unit heat exchanger E14 absorbs the refrigerant vapor from the third refrigeration unit heat exchanger E13. The concentrated lithium bromide solution is diluted to a dilute lithium bromide solution with a mass percentage of 50-54% (e.g., 50%, 52%, 54%). The heat released in the absorption process is carried away by the low-temperature circulating water from the heat collecting tank E6 in the pipe line. The dilute lithium bromide solution enters the first refrigeration unit heat exchanger E10 under the boosted pressure of the first solution pump E16. The dilute lithium bromide solution is heated in the shell side of the first refrigeration unit heat exchanger E10 by circulating hot water with a temperature exceeding 75°C from the second heat extraction coil E8 in the heat exchanger tube side. During this process, the refrigerant in the dilute lithium bromide solution evaporates into refrigerant vapor and enters the second refrigeration unit heat exchanger E11. The dilute lithium bromide solution in the first refrigeration unit heat exchanger E10 is heated and concentrated into a concentrated lithium bromide solution with a mass percentage of 58-64% (e.g., 58%, 60%, 64%). The solution is then throttled and reduced in pressure by the throttle valve E15 and returned to the fourth refrigeration unit heat exchanger E14. The temperature of the heat exchanger from the first refrigeration unit E10 is 75-85°C (e.g., 85°C). The refrigerant vapor with an absolute pressure of 6.5-8 kPa (e.g., 6.5 kPa, 7 kPa, 8 kPa) is cooled and liquefied in the shell side of the heat exchanger E11 of the second refrigeration unit by the low-temperature circulating water from the outlet of the heat exchanger tube side of the fourth refrigeration unit in the heat exchanger tube side into a liquid refrigerant with a temperature of 75-85 ° C (e.g., 75 ° C, 80 ° C, 85 ° C) and an absolute pressure of 6.5-8 kPa (e.g., 6.5 kPa, 6.8 kPa, 8 kPa), and then flows out of the heat exchanger E11 of the second refrigeration unit and is throttled down by the first throttle valve E12 to a temperature of 2-5 ° C (e.g., 2 ° C, 4 ° C, 5 ° C) and an absolute pressure of 0.8-0.9 kPa (e.g., 0.8 kPa). , 0.85 kPa, 0.9 kPa) enters the third refrigeration unit heat exchanger E13. The liquid refrigerant with a temperature of 2-5°C (e.g., 2°C, 4°C, 5°C) and an absolute pressure of 0.8-0.9 kPa (e.g., 0.8 kPa, 0.85 kPa, 0.9 kPa) absorbs heat from the circulating chilled water in the heat exchanger tube side in the shell side of the third refrigeration unit heat exchanger E13, thereby evaporating into refrigerant vapor with a temperature of 2-5°C (e.g., 2°C, 4°C, 5°C) and an absolute pressure of 0.8-0.9 kPa (e.g., 0.8 kPa, 0.85 kPa, 0.9 kPa). The refrigerant then returns to the fourth refrigeration unit heat exchanger E14, completing the refrigeration cycle of the lithium bromide refrigeration unit.

[0121] The waste heat recovery cycle steps in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit adopt the same steps as the waste heat recovery cycle in the cooling mode of the soil source heat pump;

[0122] The user-side chilled water cycle includes the following steps:

[0123] Chilled water returning from the supplemental cooling heat exchanger E23, fan coil unit E21, and fresh air heat exchanger E22, which has a temperature exceeding 12°C, enters the first tube pass of the heat pump heat exchanger E17 for heat exchange and cooling. The cooled chilled water, now at a temperature of 10-12°C (e.g., 10°C, 11°C, or 12°C), flows from the heat pump heat exchanger E17 through a second connecting pipeline into the third refrigeration unit heat exchanger E13. Within the tube pass of the third refrigeration unit heat exchanger E13, the chilled water is cooled to approximately 7°C by the refrigerant in the shell pass of the heat exchanger, which has a temperature of 2-5°C (e.g., 2°C, 4°C, or 5°C). The chilled water then enters the fan coil unit heat exchange circulation pipeline under pressure from the fifth water pump P5 and returns to the user-side fan coil unit E21, fresh air heat exchanger E22, and supplemental cooling heat exchanger E23, completing the user-side chilled water circulation.

[0124] The high-temperature hot water supply comprises the following steps:

[0125] The high-temperature refrigerant at 80-110°C (e.g., 80°C, 100°C, 110°C) from the solar thermal collector E1 enters the upper heat collecting coil E2 and exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, and then returns to the solar thermal collector E1 under the pressure of the first water pump P1; the hot water stored in the middle and upper part of the heat collecting tank E6 is heated to 60-90°C by the upper heat collecting coil E2; the hot water stored in the lower part of the heat collecting tank E6 enters the pipe side of the fourth refrigeration unit heat exchanger E14 under the push of the fourth water pump P4, and exchanges heat with the lithium bromide solution in the shell side of the fourth refrigeration unit heat exchanger, and the temperature rises to 45-5 The heated circulating water flows out of the heat exchanger E14 of the fourth refrigeration unit and enters the pipe side of the heat exchanger E11 of the second refrigeration unit, and is heated to 50-70°C (such as 50°C, 60°C, 70°C) by the refrigerant at 75-85°C (such as 75°C, 78°C, 85°C) in the shell side of the heat exchanger of the second refrigeration unit, and then returns to the heat collection tank E6; the low-temperature circulating water of 35-45°C (such as 35°C, 40°C, 45°C) after heat exchange in the lower heat collection coil E25 at the bottom of the heat collection tank E6 enters the second pipe side of the heat pump heat exchanger E19, and is heated to 50-70°C (such as 50°C, 60°C, 70°C) by the refrigerant at 75-85°C (such as 75°C, 78°C, 85°C) in the shell side of the heat exchanger of the second refrigeration unit. The gaseous refrigerant at 55-75°C (e.g., 55°C, 60°C, 75°C) is heated by heat exchange and is heated to 45-55°C (e.g., 45°C, 50°C, 55°C), and returns to the lower heat collecting coil E25 under the pressure of the sixth water pump P6; driven by the second water pump P2, the high-temperature stored water at the top of the heat collecting tank E6 with a temperature of 60-90°C (e.g., 60°C, 78°C, 90°C) enters the heat taking tank E7 through the lower circulating water inlet of the heat taking tank E7, and the low-temperature stored water at the bottom of the heat taking tank E7 with a temperature below 50°C enters the top of the heat collecting tank E6 through the lower circulating water outlet, achieving high quality of the heat collecting tank E6. Potential heat energy is transferred to the hot water tank E7. Domestic tap water enters the first heat extraction coil E4 and exchanges heat with the hot water stored in the middle of the hot water tank E7 to increase its temperature. The heated tap water at 50-60°C (e.g., 50°C, 56°C, 60°C) is delivered to users to meet their domestic hot water needs. The high-temperature hot water exceeding 75°C in the second heat extraction coil E8 at the top of the hot water tank E7 enters the tube side of the first refrigeration unit heat exchanger E10, where it exchanges heat with the lithium bromide solution in the shell side and cools down to approximately 70°C, providing high-quality heat energy for the lithium bromide absorption refrigeration unit. The circulating water, which has been heated, is pumped by the third water pump P3 and returns to the second heat extraction coil E8, completing the high-temperature hot water supply.

[0126] The refrigeration cycle steps of the soil source heat pump unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplement adopt the same steps as the refrigeration cycle steps of the soil source heat pump unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit;

[0127] The refrigeration cycle steps of the lithium bromide absorption refrigeration unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplement adopt the same steps as the refrigeration cycle steps of the lithium bromide absorption refrigeration unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit;

[0128] The waste heat recovery cycle steps in the combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation adopt the same steps as the waste heat recovery cycle in the ground source heat pump cooling mode;

[0129] The user-side chilled water circulation steps in the combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation adopt the same steps as the user-side chilled water circulation steps in the ground source heat pump cooling mode;

[0130] The high-temperature hot water supply adopts the following steps:

[0131] The high-temperature refrigerant at 60-80°C (e.g., 60°C, 78°C, 80°C) in the solar thermal collector E1 enters the upper heat collecting coil E2 and exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, where it is cooled to 50-60°C (e.g., 50°C, 55°C, 60°C). It then returns to the solar thermal collector E1 under the pressure of the water pump P1. The hot water stored in the heat collecting tank E6 is heated to 50-70°C (e.g., 50°C, 60°C, 70°C) by the upper heat collecting coil E2. The hot water stored in the lower part of the heat collecting tank E6 enters the tube side of the fourth refrigeration unit heat exchanger E14 under the push of the fourth water pump P4, exchanges heat with the lithium bromide solution in the shell side of the heat exchanger of the fourth refrigeration unit, and is heated to 45-50°C. ℃ (e.g., 45℃, 48℃, 50℃) circulating water flows out of the fourth refrigeration unit heat exchanger E14 and enters the pipe side of the second refrigeration unit heat exchanger E11, and is reheated by the gaseous refrigerant of 75-85℃ (e.g., 75℃, 80℃, 85℃) in the shell side of the second refrigeration unit heat exchanger, and the circulating water heated to 50-70℃ (e.g., 50℃, 60℃, 70℃) returns to the heat collection tank E6; the low-temperature circulating water of 35-45℃ (e.g., 35℃, 40℃, 45℃) in the lower heat collection coil E25 at the bottom of the heat collection tank E6 enters the second pipe side of the heat pump heat exchanger E19, and is heated to 55-75℃ (e.g., 55℃, 60℃) in the first pipe side of the heat pump heat exchanger. The gaseous refrigerant (e.g., 75°C) is heated by heat exchange and heated to 45-55°C (e.g., 45°C, 48°C, 55°C), and returns to the lower heat collecting coil E25 under the pressure of the sixth water pump P6; the high-temperature stored water at 50-70°C (e.g., 50°C, 65°C, 70°C) at the top of the heat collecting tank E6 enters the bottom of the hot water tank E7 under the push of the second water pump P2, and the low-temperature stored water at the bottom of the hot water tank E7 with a temperature lower than 50°C enters the top of the heat collecting tank E6 through the lower circulating water outlet of the hot water tank E7, realizing the transfer of high-quality thermal energy from the heat collecting tank E6 to the hot water tank E7; the circulating water at the top of the hot water tank E7 enters the fuel tank E7 through the heat supply circulation pipeline under the pressure of the seventh water pump P7. The gas-fired hot water boiler E20 heats up the hot flue gas in the boiler, raising the temperature to 80°C, and returns to the hot water tank E7. Domestic tap water enters the first heat exchange coil E4, where it heats up the hot water in the middle of the hot water tank E7. The heated tap water, at a temperature of 50-60°C (e.g., 50°C, 55°C, or 60°C), is delivered to users, meeting their domestic hot water needs. The hot water exceeding 75°C in the second heat exchange coil E8 at the top of the hot water tank E7 enters the heat exchanger E10 of the first refrigeration unit, providing high-quality thermal energy for the heat exchanger. The heat exchanged circulating water is then pumped by the third water pump P3 back to the first heat collection coil E8, completing the high-temperature hot water supply.

[0132] The heating cycle of the soil source heat pump unit includes the following steps:

[0133] The compressor E18 of the soil source heat pump unit compresses the gaseous refrigerant at -5 to 10°C (e.g., -5°C, 5°C, 10°C) into a gaseous refrigerant at 60 to 80°C (e.g., 60°C, 65°C, 80°C). The compressed refrigerant flows into the second pipe side of the heat pump heat exchanger E17, and exchanges heat with the hot water return water from the fan coil E21 on the user side and the fresh air heat exchanger E22 in the first pipe side of the heat pump heat exchanger. After that, the refrigerant is cooled and liquefied into a liquid refrigerant at 45 to 55°C (e.g., 45°C, 50°C, 55°C). The liquid refrigerant then flows into the throttle valve E20. The liquid refrigerant is cooled and liquefied into a liquid refrigerant at 45 to 55°C (e.g., 45°C, 50°C, 55°C). After throttling by the throttle valve E20, the gas-liquid two-phase mixed refrigerant expands to a temperature between -10°C and 5°C (e.g., -10°C, 0°C, and 5°C). The gas-liquid two-phase mixed refrigerant enters the first tube side of the heat pump heat exchanger E19. Within the heat pump heat exchanger E19, the mixed refrigerant absorbs heat from the circulating return water entering the second tube side of the heat pump heat exchanger and from the ground source heat exchanger E9. The temperature of the mixed refrigerant is then increased. The mixed refrigerant is heated to a temperature between -5°C and 10°C (e.g., -5°C, 0°C, and 10°C) and then returns to the ground source heat pump unit compressor E18, thus completing the heating cycle of the ground source heat pump unit.

[0134] The user-side heating cycle includes the following steps:

[0135] The 40°C hot water return from the user-side fan coil unit E21 and fresh air heat exchanger E22 enters the first tube pass of the heat pump heat exchanger E17, where it exchanges heat with the 60-80°C (e.g., 60°C, 70°C, 80°C) gaseous refrigerant in the second tube pass of the heat pump heat exchanger to increase its temperature. The 45°C hot water flows out of the first tube pass of the heat pump heat exchanger E17 and, under the pressure of the fifth water pump P5, passes through the fan coil heat exchange pipeline to enter the user-side fan coil unit E21 and fresh air heat exchanger E22 for heat exchange. The water then returns to the first tube pass of the heat pump heat exchanger E17, completing the user-side heating cycle.

[0136] The domestic hot water supply comprises the following steps:

[0137] The high-temperature refrigerant at 50-80°C (e.g., 50°C, 70°C, 80°C) in the solar thermal collector E1 enters the upper heat collecting coil E2 and exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, where it is cooled to 45-60°C (e.g., 45°C, 50°C, 60°C). It then returns to the solar thermal collector E1 under the pressure of the first water pump P1; the hot water stored in the heat collecting tank E6 is heated to 45-65°C (e.g., 45°C, 50°C, 65°C) by the upper heat collecting coil E2; the high-temperature hot water stored at the top of the heat collecting tank E6, with a temperature of 45-65°C (e.g., 45°C, 50°C, 65°C), is driven by the second water pump P2 to enter the bottom of the hot water taking tank E7, and the low-temperature hot water stored at the bottom of the hot water taking tank E7, which is lower than 40°C, is taken. The circulating water enters the top of the heat collection tank E6 through the lower circulating water outlet, transferring the high-quality heat energy from the heat collection tank E6 to the hot water tank E7. The circulating water at the top of the hot water tank E7, with a temperature of 40-60°C (e.g., 40°C, 50°C, 60°C), is pressurized by the seventh water pump P7 and enters the gas-fired hot water boiler E20. After heat exchange with the high-temperature flue gas in the gas-fired hot water boiler E20 and heating it to approximately 70°C, it returns to the hot water tank E7. Domestic tap water enters the first heating coil E4 and heat-exchanges with the stored water in the middle of the hot water tank E7, heating it to a temperature of 50-60°C (e.g., 50°C, 55°C, 60°C). This heated tap water is then delivered to users, meeting their domestic hot water needs. This completes the domestic hot water supply.

[0138] The heating cycle steps of the ground source heat pump unit in the gas-heating supplementary ground source heat pump heating mode are the same as those of the ground source heat pump unit in the ground source heat pump heating mode;

[0139] The user-side heating cycle includes the following steps:

[0140] Hot water return water at a temperature below 40°C from the user-side fan coil unit E21 and fresh air heat exchanger E22 enters the first tube pass of the heat pump heat exchanger E17 for heat exchange with the 60-80°C (e.g., 60°C, 70°C, 80°C) gaseous refrigerant in the second tube pass of the heat pump heat exchanger. The hot water, heated to 40-44°C (e.g., 40°C, 41°C, 44°C), flows out of the first tube pass of the heat pump heat exchanger E17 and, under pressure from the fifth water pump P5, enters the gas-fired hot water boiler E20 through the supplementary heat circulation pipeline for further heat exchange with the high-temperature flue gas. The heated hot water, now at a temperature exceeding 45°C, flows out of the gas-fired hot water boiler E20 for heat exchange with the user-side fan coil unit E21 and fresh air heat exchanger E22, and then returns to the first tube pass of the heat pump heat exchanger E17, thus completing the user-side heating cycle.

[0141] The domestic hot water supply comprises the following steps:

[0142] The high-temperature refrigerant at 50-80℃ (e.g. 60℃, 70℃, 80℃) in the solar thermal collector E1 enters the upper heat collecting coil E2 and exchanges heat with the hot water stored in the upper part of the heat collecting tank E6, and then returns to the solar thermal collector E1 under the pressure of the first water pump P1; the hot water stored in the heat collecting tank is heated to 45-65℃ (e.g. 45℃, 50℃, 65℃) by the upper heat collecting coil E2; the temperature of the top of the heat collecting tank E6 is between 50-80℃ (e.g. 50℃, 70℃, 80℃) The high-temperature stored hot water (0°C) enters the bottom of the hot water tank E7 under the push of the second water pump P2. The low-temperature stored hot water at the bottom of the hot water tank E7, which is lower than 40°C, enters the top of the hot water collecting tank E6 through the lower circulating water outlet, thereby transferring the high-quality thermal energy from the hot water collecting tank E6 to the hot water tank E7. Domestic tap water enters the first heat extraction coil E4 and exchanges heat with the stored hot water in the middle of the hot water tank E7 to increase its temperature. The heated tap water is then delivered to users at a temperature of 40-60°C (e.g., 40°C, 50°C, 60°C), meeting their domestic hot water needs. In this way, domestic hot water supply is completed.

[0143] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A multi-energy coupled cooling and heating system for buildings in long-term cooling areas, characterized by: It includes a heat source hierarchical management unit, a solar thermal collection unit, a lithium bromide absorption refrigeration unit, a gas heating supplement unit, a soil source heat pump cooling and heating unit, and an indirect evaporative cooling waste heat recovery unit; the heat source hierarchical management unit is connected to the solar thermal collection unit, the lithium bromide absorption refrigeration unit, the gas heating supplement unit, and the soil source heat pump cooling and heating unit; the soil source heat pump cooling and heating unit is connected to the lithium bromide absorption refrigeration unit, the gas heating supplement unit, and the indirect evaporative cooling waste heat recovery unit; The lithium bromide absorption refrigeration unit comprises a first refrigeration unit heat exchanger (E10), wherein the first shell-side outlet of the first refrigeration unit heat exchanger is sequentially connected to the shell-side inlet of the second refrigeration unit heat exchanger (E11), the shell-side outlet of the second refrigeration unit heat exchanger, the first throttle valve (E12), the shell-side inlet of the third refrigeration unit heat exchanger (E13), the shell-side outlet of the third refrigeration unit heat exchanger, the shell-side inlet of the fourth refrigeration unit heat exchanger (E14), the shell-side outlet of the fourth refrigeration unit heat exchanger, the first solution pump (E16) and the shell-side inlet of the first refrigeration unit heat exchanger through a refrigeration cycle pipeline; the second outlet of the first refrigeration unit heat exchanger is connected to the second shell-side inlet of the fourth refrigeration unit heat exchanger through a return pipeline equipped with a throttle valve (E15); wherein the first refrigeration unit heat exchanger, the second refrigeration unit heat exchanger, the third refrigeration unit heat exchanger The heat exchanger and the fourth refrigeration unit heat exchanger are sequentially connected in series to form a ring-shaped lithium bromide absorption refrigeration unit; the outlet of the fan coil (E21) is sequentially connected to the first pipe side inlet of the soil source heat pump heat exchanger (E17), the first pipe side outlet of the soil source heat pump heat exchanger, the tenth valve (V10), the fifth water pump (P5), the fourteenth valve (V14), the sixteenth valve (V16) and the inlet of the fan coil through the fan coil heat exchange circulation pipeline; the inlet of the first connecting pipeline equipped with the ninth valve (V9) is connected to the fan coil heat exchange circulation pipeline located between the first pipe side outlet of the soil source heat pump heat exchanger and the tenth valve, and the outlet is connected to the pipe side inlet of the third refrigeration unit heat exchanger; the inlet of the second connecting pipeline is connected to the pipe side outlet of the third refrigeration unit heat exchanger, and the outlet is connected to the fan coil heat exchange circulation pipeline between the tenth valve and the fifth water pump (P5); The soil source heat pump cooling and heating unit includes a soil source heat pump heat exchanger second pipe side outlet, a compressor (E18), a heat pump heat exchanger (E19) first pipe side inlet, the heat pump heat exchanger first pipe side outlet, a second throttle valve (E20) and the soil source heat pump heat exchanger second pipe side inlet which are sequentially connected through a soil source circulation pipeline; the heat pump heat exchanger, the soil source heat pump unit compressor, the heat pump heat exchanger and the second throttle valve are connected in series to form a ring-shaped soil source heat pump unit; the heat pump heat exchanger second shell side outlet is sequentially connected to a sixth water pump (P6), a seventh valve (V7) and the inlet of the buried pipe heat exchanger (E9), the buried pipe heat exchanger outlet, an eighth valve (V8) and the heat pump heat exchanger second shell side inlet through a heat pump heat exchange circulation pipeline; One end of the third connecting pipeline is connected to the inlet of the fresh air heat exchanger (E22) and the other end is connected to the fan coil circulation pipeline located between the fourteenth valve and the sixteenth valve (V16); one end of the fourth connecting pipeline is connected to the outlet of the fresh air heat exchanger and the other end is connected to the fan coil heat exchange circulation pipeline located between the first pipe side inlet of the soil source heat pump heat exchanger and the outlet of the fan coil (E21); The gas heating unit includes a gas heating water heater, and the heat source hierarchical management unit includes a hot water tank (E7). The hot water outlet of the hot water tank is connected in sequence to the seventh water pump (P7), the twelfth valve (V12), the heating inlet of the gas hot water heating furnace, the heating outlet of the gas hot water heating furnace, the fifteenth valve (V15), the eleventh valve (V11), and the hot water inlet of the hot water tank through a heating circulation pipeline; one end of a fifth connecting pipeline is connected to the heating circulation pipeline located between the fourteenth valve (V14) and the eleventh valve, and the other end is connected to the fan coil heat exchange circulation pipeline located between the fifteenth valve and the sixteenth valve (V16); one end of a sixth connecting pipeline equipped with a thirteenth valve (V13) is connected to the fan coil heat exchange circulation pipeline located between the fourteenth valve and the fifth water pump, and the other end is connected to the heating circulation pipeline located between the twelfth valve and the heating inlet of the gas heating water heater; The indirect evaporative cooling waste heat recovery unit comprises an indirect evaporative cooler (E24) and a supplementary cooling heat exchanger (E23), wherein the wet channel outlet of the indirect evaporative cooler is sequentially connected to the inlet of the cooling side pipeline of the supplementary cooling heat exchanger, the outlet of the cooling side pipeline, the eighth water pump (P8), and the wet channel inlet of the indirect evaporative cooler through a cooling circulation pipeline; the inlet of the cooling side pipeline of the supplementary cooling heat exchanger is connected to the fan coil heat exchange circulation pipeline located between the fifth water pump (P5) and the fourteenth valve (V14) through a seventh connecting pipeline equipped with an eighteenth valve (V18); the outlet of the cooling side pipeline of the supplementary cooling heat exchanger is connected to the fan coil circulation pipeline located between the first pipe side inlet of the ground source heat pump heat exchanger and the outlet of the fan coil (E21) through an eighth connecting pipeline equipped with a nineteenth valve (V19); the dry channel inlet of the indirect evaporative cooler (E24) is connected to the outdoor fresh air, and the dry channel outlet is connected to the air inlet of the fresh air heat exchanger; The heat source hierarchical management unit includes a heat collecting tank (E6) and the hot water taking tank; the upper circulating water outlet of the heat collecting tank at the top is sequentially connected to a second water pump (P2), a second solenoid valve (V2), and a lower circulating water inlet at the bottom of the hot water taking tank via a ninth connecting pipeline; the lower circulating water outlet of the hot water taking tank at the bottom is sequentially connected to a first solenoid valve (V1) and an upper circulating water inlet at the top of the heat collecting tank via a tenth connecting pipeline; the outlet of a first heat extraction coil (E4) arranged in the middle of the hot water taking tank is connected to a domestic water terminal (E3); The solar heat collection unit includes a solar heat collector (E1) and an upper heat collection coil located above the interior of a heat collection tank. The outlet of the solar heat collector is connected to the inlet of the heat collection coil. After heat exchange with the hot water stored in the heat collection tank, the outlet of the upper heat collection coil is connected to the inlet of the solar heat collector via a first water pump. A lower heat collection coil (E25) is provided below the interior of the heat collection tank. The connection structure of the lithium bromide absorption refrigeration unit and the heat source hierarchical management unit is as follows: the heat collection hot water outlet at the lower part of the heat collection tank (E6) is connected in sequence to the fourth water pump (P4), the third valve (V3) and the pipe side inlet of the heat exchanger of the fourth refrigeration unit through an eleventh connecting pipeline; the pipe side outlet of the fourth refrigeration unit heat exchanger is connected to the pipe side inlet of the second refrigeration unit heat exchanger, the pipe side outlet of the second refrigeration unit heat exchanger, the fourth valve (V4) and the heat collection hot water inlet at the lower part of the heat collection tank; the pipe side outlet of the first refrigeration unit heat exchanger is connected in sequence to the third water pump and the inlet of the second heat extraction coil arranged at the top of the hot water extraction tank through a twelfth connecting pipeline; the outlet of the second heat extraction coil is connected to the pipe side inlet of the heat exchanger of the first refrigeration unit; The connection between the soil source heat pump cooling and heating unit and the heat source hierarchical management unit is as follows: the outlet of the lower heat collection coil (E25) is connected to the heat pump heat exchange circulation pipeline located between the eighth valve and the second pipe side inlet of the heat pump heat exchanger (E19) through the nineteenth connecting pipeline installed with the sixth valve (V6); the inlet of the lower heat collection coil is connected to the heat pump heat exchange circulation pipeline located between the seventh valve and the sixth water pump through the twentieth connecting pipeline installed with the fifth valve (V5).

2. A method for operating the multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to claim 1, characterized in that: It includes cooling mode and heating mode; the cooling mode includes ground source heat pump cooling mode, ground source heat pump and lithium bromide absorption refrigeration unit combined cooling mode and ground source heat pump and gas heating lithium bromide absorption refrigeration unit combined cooling mode; The specific control process of the ground source heat pump cooling mode is as follows: By controlling the valves and water pumps, the connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit, lithium bromide absorption refrigeration unit, and gas heating unit is cut off; the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit and gas heating unit is cut off; the connection between the ground source heat pump cooling and heating unit and the indirect evaporative cooling waste heat recovery unit is connected, forming the ground source heat pump unit refrigeration cycle, waste heat recovery cycle, user-side chilled water cycle, and domestic hot water supply; the control process of the valves and water pumps is as follows: Close the third valve (V3), the fourth valve (V4), the fifth valve (V5), the sixth valve (V6), the ninth valve (V9), the eleventh valve (V11), the twelfth valve (V12), the thirteenth valve (V13), and the fifteenth valve (V15); open the first valve (V1), the second valve (V2), the seventh valve (V7), the eighth valve (V8), the tenth valve (V10), the fourteenth valve (V14), the sixteenth valve (V16), the seventeenth valve (V17), the eighteenth valve (V18), and the nineteenth valve (V19); start the first water pump (P1), the second water pump (P2), the fifth water pump (P5), the sixth water pump (P6), and the eighth water pump (P8); and operate the annular ground source heat pump unit; The control process of the combined cooling mode of the ground source heat pump and lithium bromide absorption refrigeration unit is as follows: By controlling the valves and water pumps, the connection between the gas heating unit and the ground source heat pump cooling and heating unit and the heat source hierarchical management unit is cut off; the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected; the connection between the heat source hierarchical management unit and the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected, forming a ground source heat pump unit refrigeration cycle, a lithium bromide absorption refrigeration unit refrigeration cycle, a waste heat recovery cycle, and a user-side chilled water cycle and high-temperature hot water supply; the control of the valves and water pumps is as follows: Close the seventh valve, the eighth valve, the tenth valve, the eleventh valve (V11), the twelfth valve (V12), the thirteenth valve (V13), and the fifteenth valve (V15); open the first valve, the second valve, the third valve, the fourth valve, the fifth valve, the sixth valve, the ninth valve (V9), the fourteenth valve (V14), the sixteenth valve (V16), the seventeenth valve (V17), the eighteenth valve (V18), and the nineteenth valve (V19); start the first water pump, the second water pump, the third water pump, the fourth water pump, the fifth water pump, the sixth water pump, and the eighth water pump; operate the annular ground source heat pump unit and the annular lithium bromide absorption refrigeration unit; The combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation includes the following steps: By controlling the water pump and valve, the connection between the gas heating unit and the ground source heat pump cooling and heating unit is cut off; the connection between the heat source hierarchical management unit and the ground source heat pump cooling and heating unit, the lithium bromide absorption refrigeration unit, and the gas heating unit is connected; the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit is connected, forming the ground source heat pump unit refrigeration cycle, the lithium bromide absorption refrigeration unit refrigeration cycle, the waste heat recovery cycle, the user-side chilled water cycle, and the high-temperature hot water supply; the control of the water pump and valve is as follows: Specifically, close the seventh valve, the eighth valve, the tenth valve, the thirteenth valve (V13) and the fifteenth valve (V15), and open the first valve, the second valve, the third valve, the fourth valve, the fifth valve, the sixth valve, the ninth valve (V9), the eleventh valve (V11), the twelfth valve (V12), the fourteenth valve (V14), the sixteenth valve (V16), the seventeenth valve (V17), the eighteenth valve (V18) and the nineteenth valve (V19); start the first water pump, the second water pump, the third water pump, the fourth water pump, the fifth water pump, the sixth water pump, the seventh water pump and the eighth water pump, start the gas heating hot water boiler (E20); operate the annular ground source heat pump unit and the annular lithium bromide absorption refrigeration unit; The heating modes include a ground source heat pump heating mode and a gas-fired ground source heat pump heating mode. The ground source heat pump heating modes are as follows: The soil source heat pump heating mode includes the following steps: By controlling the valves and water pumps, the connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit, lithium bromide absorption refrigeration unit, gas heating unit, and indirect evaporative cooling waste heat recovery unit is cut off; the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit is cut off; the connection between the heat source hierarchical management unit and the gas heating unit is connected, forming the ground source heat pump unit heating cycle, the user-side heating cycle, and the domestic hot water supply. The control steps of the valves and water pumps are as follows: Close the third valve, the fourth valve, the fifth valve, the sixth valve, the ninth valve (V9), the thirteenth valve (V13), the fifteenth valve (V15), the eighteenth valve (V18), and the nineteenth valve (V19); open the first valve, the second valve, the seventh valve, the eighth valve, the tenth valve, the eleventh valve (V11), the twelfth valve (V12), the fourteenth valve (V14), the sixteenth valve (V16), and the seventeenth valve (V17); start the first water pump, the second water pump, the fifth water pump, the sixth water pump, and the seventh water pump; operate the annular ground source heat pump unit and the gas heating water boiler (E20); The gas-fired ground source heat pump heating mode includes the following steps: By controlling the water pump and valve, the connection between the ground source heat pump cooling and heating unit and the lithium bromide absorption refrigeration unit and the indirect evaporative cooling waste heat recovery unit is cut off, and the connection between the heat source hierarchical management unit and the lithium bromide absorption refrigeration unit and the gas heating unit is cut off. The connection between the ground source heat pump cooling and heating unit and the heat source hierarchical management unit and the gas heating unit is connected, forming a ground source heat pump unit heating cycle, a user-side heating cycle, and a domestic hot water supply. The control steps of the water pump and valve are as follows: Close the third valve, the fourth valve, the seventh valve, the eighth valve, the ninth valve (V9), the eleventh valve (V11), the twelfth valve (V12), the fourteenth valve (V14), the eighteenth valve (V18), and the nineteenth valve (V19); open the first valve, the second valve, the fifth valve, the sixth valve, the tenth valve, the thirteenth valve (V13), the fifteenth valve (V15), the sixteenth valve (V16), and the seventeenth valve (V17); start the first water pump, the second water pump, the fifth water pump, and the sixth water pump; operate the annular ground source heat pump unit and the gas heating water boiler (E20); the gas heating water boiler and the ground source heat pump unit jointly provide heat.

3. The method for operating a multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to claim 2, characterized in that: The refrigeration cycle of the soil source heat pump unit: The compressor (E18) of the soil source heat pump unit compresses the low-temperature gaseous refrigerant into a high-temperature gaseous refrigerant. The compressed refrigerant flows into the heat pump heat exchanger (E19), exchanges heat with the circulating water return from the soil heat exchanger (E9), and is cooled and liquefied into a liquid refrigerant. The refrigerant then flows into the throttle valve (E20). The liquid refrigerant is throttled by the throttle valve (E20) and expands to become a gas-liquid two-phase mixed refrigerant. The gas-liquid two-phase mixed refrigerant enters the heat pump heat exchanger (E17). After absorbing heat from the user-side cooling circulation return water in the heat pump heat exchanger (E17), the temperature rises, and the gas-liquid two-phase mixed refrigerant becomes superheated refrigerant vapor. The superheated refrigerant vapor finally returns to the compressor (E18) of the soil source heat pump unit, thus completing the refrigeration cycle of the soil source heat pump unit. The waste heat recovery cycle comprises the following steps: The cooling water flowing out of the wet channel outlet of the indirect evaporative cooler (E24) enters the supplementary cold heat exchanger (E23), exchanges heat with the chilled water in the cold side pipeline of the supplementary cold heat exchanger (E23) to reduce its temperature. The cooled cooling water enters the wet channel of the indirect evaporative cooler (E24) under the pressure of the eighth water pump, directly exchanges heat and moisture with the indoor exhaust air of the building in the wet channel, and indirectly exchanges heat with the outdoor fresh air in the dry channel on the other side. The cooling water then flows out of the wet channel outlet of the indirect evaporative cooler and returns to the supplementary cold heat exchanger (E23), thus completing the waste heat recovery cycle. The user-side chilled water cycle includes the following steps: The chilled water return water flowing out of the supplementary cooling heat exchanger (E23), the fan coil unit (E21) and the fresh air heat exchanger (E22) enters the first tube pass of the heat pump heat exchanger (E17) to exchange heat with the gas-liquid two-phase mixed refrigerant in the second tube pass of the heat pump heat exchanger for cooling. Then, the chilled water flowing out of the outlet of the first tube pass of the heat pump heat exchanger (E17) returns to the fan coil unit (E21), the fresh air heat exchanger (E22) and the supplementary cooling heat exchanger (E23) on the user side under the pressure of the fifth water pump, thus completing the user-side chilled water cycle. The domestic hot water supply comprises the following steps: The high-temperature refrigerant in the solar thermal collector enters the upper heat collecting coil and exchanges heat with the stored water in the upper part of the heat collecting tank, where it is cooled down and then returns to the solar thermal collector under the pressure of the water pump; the stored water in the heat collecting tank is heated by the heat collecting coil; the high-temperature stored water at the top of the heat collecting tank enters the bottom of the heat taking tank through the lower circulating water inlet of the heat taking tank under the push of the second water pump, and the low-temperature stored water at the bottom of the heat taking tank enters the top of the heat collecting tank through the lower circulating water outlet, thus transferring the high-quality heat energy from the heat collecting tank to the heat taking tank; domestic tap water enters the first heat taking coil and exchanges heat with the stored water in the middle of the heat taking tank to increase the temperature and be supplied to the user.

4. The method for operating a multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to claim 3, characterized in that: The refrigeration cycle of the soil source heat pump unit includes the following steps: The soil source heat pump unit compressor (E18) compresses low-temperature refrigerant vapor into high-temperature refrigerant vapor. The compressed refrigerant flows into the heat pump heat exchanger (E19), exchanges heat with the circulating water return from the lower heat collecting coil (E25), and then cools down and liquefies into liquid refrigerant. The refrigerant then flows into the throttle valve (E20). The liquid refrigerant is throttled by the throttle valve (E20) and expands to become a gas-liquid two-phase mixed refrigerant. The gas-liquid two-phase mixed refrigerant enters the second pipe side of the heat pump heat exchanger (E17). In the heat pump heat exchanger (E17), the temperature rises after heat exchange with the user-side cooling circulation return water in the first pipe side. The gas-liquid two-phase mixed refrigerant becomes superheated refrigerant vapor. The superheated refrigerant vapor finally returns to the soil source heat pump unit compressor (E18), thus completing the refrigeration cycle of the soil source heat pump unit. The refrigeration cycle of the lithium bromide absorption refrigeration unit comprises the following steps: The refrigerant vapor flowing out of the third refrigeration unit heat exchanger (E13) enters the fourth refrigeration unit heat exchanger (E14), and the concentrated lithium bromide solution in the fourth refrigeration unit heat exchanger (E14) absorbs the refrigerant vapor from the third refrigeration unit heat exchanger (E13), and the concentrated lithium bromide solution is diluted into a dilute lithium bromide solution. The heat released in the absorption process is taken away by the low-temperature circulating water from the heat collection tank in the pipe side; the dilute lithium bromide solution enters the first refrigeration unit heat exchanger under the boost of the first solution pump (E16), and the dilute lithium bromide solution is heated in the shell side of the first refrigeration unit heat exchanger by the circulating hot water from the second heat extraction coil in the heat exchanger pipe side. In this process, the refrigerant in the dilute lithium bromide solution evaporates into refrigerant vapor and enters the second refrigeration unit heat exchanger (E11). The dilute lithium bromide solution in the first refrigeration unit heat exchanger The lithium bromide solution is heated and concentrated into a concentrated lithium bromide solution, which is then depressurized and throttled by a throttle valve (E15) and returned to the fourth refrigeration unit heat exchanger (E14); the refrigerant vapor from the first refrigeration unit heat exchanger is cooled and liquefied into a liquid refrigerant by low-temperature circulating water in the heat exchanger tube side of the second refrigeration unit heat exchanger (E11) and then flows out of the second refrigeration unit heat exchanger (E11), and then enters the third refrigeration unit heat exchanger (E13) after being depressurized and throttled into a liquid refrigerant by a first throttle valve (E12), and then absorbs heat from the circulating chilled water in the heat exchanger tube side in the shell side of the third refrigeration unit heat exchanger (E13), thereby evaporating and gasifying into refrigerant vapor, and then returning to the fourth refrigeration unit heat exchanger (E14), completing the refrigeration cycle of the lithium bromide refrigeration unit; The waste heat recovery cycle steps in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit adopt the same steps as the waste heat recovery cycle in the cooling mode of the soil source heat pump; The user-side chilled water cycle includes the following steps: The chilled water return water flowing out of the supplementary cooling heat exchanger (E23), the fan coil unit (E21) and the fresh air heat exchanger (E22) enters the first tube pass of the heat pump heat exchanger (E17) for heat exchange and cooling. The cooled chilled water flows from the heat pump heat exchanger (E17) through the second connecting pipeline into the third refrigeration unit heat exchanger (E13). The chilled water is cooled by the refrigerant in the shell pass of the heat exchanger in the tube pass of the third refrigeration unit heat exchanger (E13). Then, under the pressure of the fifth water pump, the chilled water enters the fan coil unit heat exchange circulation pipeline and returns to the user side fan coil unit (E21), the fresh air heat exchanger (E22) and the supplementary cooling heat exchanger (E23), thereby completing the user side chilled water circulation. The high-temperature hot water supply comprises the following steps: The high-temperature refrigerant from the solar thermal collector enters the upper heat collecting coil and exchanges heat with the hot water stored in the upper part of the heat collecting tank, and then cools down, and returns to the solar thermal collector under the pressure of the first water pump; the hot water stored in the upper part of the heat collecting tank is heated by the upper heat collecting coil; the hot water stored in the lower part of the heat collecting tank enters the pipe side of the fourth refrigeration unit heat exchanger (E14) under the promotion of the fourth water pump, and exchanges heat with the lithium bromide solution in the shell side of the fourth refrigeration unit heat exchanger to increase the temperature, and the heated circulating water flows out of the fourth refrigeration unit heat exchanger (E14) and enters the pipe side of the second refrigeration unit heat exchanger (E11), and is heated by the refrigerant in the shell side of the second refrigeration unit heat exchanger, and then returns to the heat collecting tank; the low-temperature circulating water after heat exchange in the lower heat collecting coil (E25) at the bottom of the heat collecting tank enters the second pipe side of the heat pump heat exchanger (E19), and exchanges heat with the gaseous refrigerant in the first pipe side of the heat pump heat exchanger. After the heat is heated, it returns to the lower heat collecting coil (E25) under the pressure of the sixth water pump; driven by the second water pump, the high-temperature stored water at the top of the heat collecting tank enters the heat taking tank through the lower circulating water inlet of the heat taking tank, and the low-temperature stored water at the bottom of the heat taking tank enters the top of the heat collecting tank through the lower circulating water outlet, thereby realizing the transfer of high-quality heat energy from the heat collecting tank to the heat taking tank; domestic tap water enters the first heat taking coil and heat exchanges with the stored water in the middle of the heat taking tank to increase its temperature, and the heated tap water is delivered to the user to meet the user's domestic hot water needs; the high-temperature hot water in the second heat taking coil at the top of the heat taking tank enters the tube side of the heat exchanger of the first refrigeration unit to exchange heat with the lithium bromide solution in the shell side for cooling, thereby providing high-quality heat energy for the lithium bromide absorption refrigeration unit; the circulating water that has been heat exchanged returns to the second heat taking coil under the drive of the third water pump, completing the high-temperature hot water supply.

5. The method for operating a multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to claim 4, characterized in that: The refrigeration cycle steps of the soil source heat pump unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplement adopt the same steps as the refrigeration cycle steps of the soil source heat pump unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit; The refrigeration cycle steps of the lithium bromide absorption refrigeration unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplement adopt the same steps as the refrigeration cycle steps of the lithium bromide absorption refrigeration unit in the combined cooling mode of the soil source heat pump and the lithium bromide absorption refrigeration unit; The waste heat recovery cycle steps in the combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation adopt the same steps as the waste heat recovery cycle in the ground source heat pump cooling mode; The user-side chilled water circulation steps in the combined cooling mode of the ground source heat pump and the lithium bromide absorption refrigeration unit with gas heat supplementation adopt the same steps as the user-side chilled water circulation steps in the ground source heat pump cooling mode; The high-temperature hot water supply adopts the following steps: The high-temperature refrigerant in the solar thermal collector enters the upper heat collecting coil and exchanges heat with the stored water in the upper part of the heat collecting tank, where it is cooled and then returns to the solar thermal collector under the pressure of the water pump; the stored water in the heat collecting tank is heated by the upper heat collecting coil; the stored water in the lower part of the heat collecting tank enters the pipe side of the fourth refrigeration unit heat exchanger (E14) under the push of the fourth water pump, exchanges heat with the lithium bromide solution in the shell side of the fourth refrigeration unit heat exchanger, and the heated circulating water flows out of the fourth refrigeration unit heat exchanger (E14) and enters the pipe side of the second refrigeration unit heat exchanger (E11), and the circulating water heated again by the gaseous refrigerant in the shell side of the second refrigeration unit heat exchanger returns to the heat collecting tank; the low-temperature circulating water in the lower heat collecting coil (E25) at the bottom of the heat collecting tank enters the second pipe side of the heat pump heat exchanger (E19), exchanges heat with the gaseous refrigerant in the first pipe side of the heat pump heat exchanger, where it is heated and then returns to the lower heat collecting coil (E19) under the pressure of the sixth water pump. 25); the high-temperature stored water at the top of the heat collecting tank enters the bottom of the hot water tank under the promotion of the second water pump, and the low-temperature stored water at the bottom of the hot water tank enters the top of the heat collecting tank through the lower circulating water outlet of the hot water tank, thereby realizing the transfer of high-quality heat energy from the heat collecting tank to the hot water tank; the circulating water located at the upper part of the hot water tank enters the gas heating hot water boiler (E20) through the heat supplementary circulation pipeline under the pressure of the seventh water pump, and the circulating water after heat exchange with the high-temperature flue gas in the gas heating hot water boiler (E20) and heating is returned to the hot water tank; domestic tap water enters the first heat extraction coil and heat exchanges with the stored water in the middle of the hot water tank to heat it and then is delivered to the user to meet the user's domestic hot water demand; the high-temperature hot water in the second heat extraction coil at the top of the hot water tank enters the heat exchanger pipe of the first refrigeration unit, providing high-quality heat energy for the heat exchanger of the first refrigeration unit; the heat exchanged circulating water returns to the first heat collecting coil under the promotion of the third water pump, completing the high-temperature hot water supply.

6. The method for operating a multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to claim 3, characterized in that: The heating cycle of the soil source heat pump unit includes the following steps: The compressor (E18) of the soil source heat pump unit compresses the low-temperature gaseous refrigerant into a high-temperature gaseous refrigerant. The compressed refrigerant flows into the second pipe side of the heat pump heat exchanger (E17), exchanges heat with the hot water return water from the fan coil unit (E21) on the user side and the fresh air heat exchanger (E22) in the first pipe side of the heat pump heat exchanger, and is cooled and liquefied into a liquid refrigerant. The liquid refrigerant then flows into the throttle valve (E20). The liquid refrigerant is throttled by the throttle valve (E20) and expands to become a gas-liquid two-phase mixed refrigerant. The gas-liquid two-phase mixed refrigerant enters the first pipe side of the heat pump heat exchanger, and absorbs heat from the circulating return water from the soil source heat exchanger (E9) in the second pipe side of the heat pump heat exchanger in the heat pump heat exchanger (E19). After that, the temperature of the gas-liquid two-phase mixed refrigerant is increased. The gas-liquid two-phase mixed refrigerant is heated to become superheated refrigerant vapor and returns to the compressor (E18) of the soil source heat pump unit, thus completing the heating cycle of the soil source heat pump unit. The user-side heating cycle includes the following steps: The hot water return from the fan coil unit (E21) and the fresh air heat exchanger (E22) on the user side enters the first tube side of the heat pump heat exchanger (E17) to exchange heat with the gaseous refrigerant in the second tube side of the heat pump heat exchanger to increase its temperature. The hot water flows out of the first tube side of the heat pump heat exchanger and, under the pressure of the fifth water pump (P5), enters the fan coil unit and the fresh air heat exchanger (E22) on the user side through the fan coil heat exchange pipeline for heat exchange, and then returns to the first tube side of the heat pump heat exchanger, thus completing the user side heating cycle. The domestic hot water supply comprises the following steps: The high-temperature refrigerant in the solar thermal collector enters the upper heat collecting coil, exchanges heat with the stored water in the upper part of the heat collecting tank, and then cools down. It then returns to the solar thermal collector under the pressure of the first water pump. The stored water in the heat collecting tank is heated by the upper heat collecting coil. The high-temperature stored water at the top of the heat collecting tank enters the bottom of the hot water tank under the pressure of the second water pump, and the low-temperature stored water at the bottom of the hot water tank enters the top of the heat collecting tank through the lower circulating water outlet, thereby transferring high-quality heat energy from the heat collecting tank to the hot water tank. The circulating water at the top of the hot water tank enters the gas-fired heating hot water boiler (E20) under the pressure of the seventh water pump, and the circulating water, after being heated by heat exchange with the high-temperature flue gas in the gas-fired heating hot water boiler (E20), returns to the hot water tank. Domestic tap water enters the first heating coil, exchanges heat with the stored water in the middle of the hot water tank, and is then supplied to users to meet their domestic hot water needs. In this way, domestic hot water supply is completed.

7. The method for operating a multi-energy coupled cooling and heating system for buildings in long-term cooling areas according to claim 6, characterized in that: The heating cycle steps of the ground source heat pump unit in the gas-heating supplementary ground source heat pump heating mode are the same as those of the ground source heat pump unit in the ground source heat pump heating mode; The user-side heating cycle includes the following steps: The hot water return water from the fan coil unit (E21) and the fresh air heat exchanger (E22) on the user side enters the first pipe side of the heat pump heat exchanger (E17), exchanges heat with the gaseous refrigerant in the second pipe side of the heat pump heat exchanger to increase the temperature, and then flows out of the first pipe side of the heat pump heat exchanger (E17). Then, under the pressure of the fifth water pump, it enters the gas heating hot water boiler (E20) through the heat supplementary circulation pipeline to exchange heat with the high-temperature flue gas to increase the temperature again. The heated hot water flows out of the gas heating hot water boiler (E20) and enters the fan coil unit (E21) and the fresh air heat exchanger (E22) on the user side for heat exchange, and then returns to the first pipe side of the heat pump heat exchanger (E17), thus completing the user-side heating cycle. The domestic hot water supply comprises the following steps: The high-temperature refrigerant in the solar thermal collector enters the upper heat collecting coil and exchanges heat with the hot water stored in the upper part of the heat collecting tank, where it is cooled and then returns to the solar thermal collector under the pressure of the first water pump; the hot water stored in the heat collecting tank is heated by the upper heat collecting coil (E2); The high-temperature stored water at the top of the heat collecting tank (E6) enters the bottom of the heat taking tank (E7) under the push of the second water pump (P2), and the low-temperature stored water at the bottom of the heat taking tank enters the top of the heat collecting tank through the lower circulating water outlet, thereby transferring the high-quality heat energy from the heat collecting tank to the heat taking tank; domestic tap water enters the first heat taking coil, exchanges heat with the stored water in the middle of the heat taking tank, and is then heated before being delivered to users, thereby meeting their domestic hot water needs; thus, domestic hot water supply is completed.

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