Municipal heat supply network return water and ground source heat pump coupling heat supply system and working method thereof

Abstract

The invention relates to the technical field of heat supply systems, in particular to a municipal heat supply network backwater and ground source heat pump coupling heat supply system and a working method thereof, and solves the problem that in the prior art, a ground source heat pump is independently adopted for heat supply, so that soil heat unbalance is easily caused, and the municipal heat supply network backwater and ground source heat pump coupling heat supply system comprises a heat supply network backwater heat compensation assembly, a heat storage assembly and a ground source heat pump assembly; the heat supply network backwater heat compensation assembly and the heat storage assembly are connected with a heat supply network backwater pipe network, the heat supply network backwater heat compensation assembly and the heat storage assembly are arranged in parallel, the heat supply network backwater heat compensation assembly or the heat storage assembly supplies heat to a user sequentially through a first valve station and a second valve station, and the ground source heat pump assembly supplies heat to the user through the second valve station. A buried pipe in the heat supply network backwater heat compensation assembly and a buried pipe in the ground source heat pump assembly are switched in parallel connection or series connection through a second valve station; or the heat storage assembly and the buried pipe in the ground source heat pump assembly are switched in parallel connection or series connection through the second valve station. The device has the advantages that water supplied to the buried pipes is heated in a cascade mode in a series connection mode, and the problem of soil thermal unbalance is relieved.

Description

Technical Field

[0001] This invention relates to the field of heating system technology, and in particular to a municipal heating network return water coupled with a ground source heat pump heating system and its working method. Background Technology

[0002] While conventional ground source heat pumps offer advantages such as renewability and decentralized on-site heat extraction, they are prone to soil thermal imbalance during long-term operation in typical cold seasons. Continuous heat extraction from the soil during winter causes a gradual decrease in ground temperature, leading to a drop in the unit's evaporation temperature, an increase in the compressor pressure ratio, and a gradual decline in the system and unit's COP. To maintain heating capacity, it is often necessary to increase the scale of buried pipes and the circulation flow rate, resulting in higher initial investment and pump consumption. Furthermore, their deployment is limited in urban areas with high heat loads. Under certain operating conditions, they may also cause the soil around the buried pipes to become excessively cold and frost, further affecting long-term stable operation.

[0003] The existing methods for utilizing waste heat from return water are mostly: indirect heating using plate heat exchangers or direct heat extraction from the return water side using a water source heat pump and then supplying it back. However, due to factors such as low return water temperature, small heat exchange temperature difference, fouling and aging of the heat exchange end, and fluctuations in the return water temperature at the end of the secondary network, these methods have limited improvement on the soil heat balance on the ground source side and have failed to form an effective synergy with the ground source heat pump.

[0004] Existing coupling or multi-energy complementary schemes, such as the patent disclosed in CN115325594A, involve a combined heating system integrating solar energy, geothermal energy, air source heat pump, and municipal heating network return water. This system includes a solar heating system, a ground source heat pump system, an air source heat pump system, a municipal heating network return water supplementary heating system, and a user-end heating system. While these systems can alleviate some of the load on the heat source side, they still have significant shortcomings. First, these schemes do not incorporate cascaded heat extraction and supplementary heating design from the perspective of introducing waste heat from the municipal heating network return water from the ground source side, thus failing to fully utilize the complementarity between waste heat from the return water and soil heat. Second, under the variable outdoor weather conditions and heat load levels during the heating season, there is a lack of effective coordinated control strategies, making it difficult to continuously expand the temperature difference between the supply and return water while ensuring stable terminal supply temperature, thereby limiting the potential for increasing transmission capacity under existing pipe diameter conditions. Furthermore, insufficient consideration is given to seasonal heat storage and heat balance restoration on the ground source side, making it prone to soil heat imbalance and system performance degradation during long-term operation.

[0005] In summary, relying solely on ground-source heat pumps for heating can easily lead to soil thermal imbalance and COP decay, making it difficult to balance long-term stability and economical operation. Currently, there is a lack of a complete technical solution that can organically introduce and efficiently utilize waste heat from the municipal heating network return water, widen the temperature difference between supply and return water, alleviate soil thermal imbalance, and improve the overall performance of the system. Summary of the Invention

[0006] This invention proposes a municipal heating network return water coupled with a ground source heat pump heating system and its working method, which solves the problem that the use of ground source heat pump heating alone in the prior art is prone to soil thermal imbalance and COP decay, and it is difficult to achieve both long-term stability and economic operation.

[0007] The technical solution of this invention is implemented as follows: A municipal heating network return water coupled with a ground source heat pump heating system includes a heating network return water replenishment component, a heat storage component, and a ground source heat pump component. The heating network return water replenishment component and the heat storage component are connected to the heating network return water pipeline, respectively. The heating network return water replenishment component and the heat storage component are arranged in parallel. The heating network return water replenishment component or the heat storage component sequentially supplies heat to users through a first valve station and a second valve station. The ground source heat pump component supplies heat to users through a second valve station. The buried pipes in the heating network return water replenishment component and the ground source heat pump component can be switched between parallel and series connection through the second valve station; alternatively, the buried pipes in the heat storage component and the ground source heat pump component can be switched between parallel and series connection through the second valve station. The buried pipes include multiple parallel U-shaped pipes. Through the coordinated operation of the heating network return water replenishment component and the ground source heat pump component, waste heat from the return water is effectively recovered, the return water temperature difference is increased, the system energy efficiency is significantly improved, and energy waste is reduced. Meanwhile, by using a series connection to heat the water supply through the underground pipes in stages, the problem of soil thermal imbalance can be effectively alleviated, ensuring the stable operation of the ground source heat pump under low-temperature conditions.

[0008] The ground source heat pump assembly also includes an evaporator and a condenser. The water supply and return pipes of the buried pipe are connected to the evaporator. A compressor is installed between the evaporator and the condenser. After absorbing heat, the heat exchange medium in the evaporator is compressed and heated by the compressor, and then enters the condenser to release heat. The condenser supplies heat to the user.

[0009] The second valve station includes a first pipeline, a second pipeline, and a third pipeline. The first pipeline connects the water supply pipe at the output end of the first valve station to the water supply pipe of the buried pipe. The second pipeline connects the return water pipe at the output end of the first valve station to the water supply pipe of the buried pipe. The third pipeline connects the return water pipe at the output end of the first valve station to the return water pipe of the buried pipe. A fifth valve is installed on the first pipeline, a seventh valve on the second pipeline, and an eighth valve on the third pipeline. A sixth valve is installed on the water supply pipe of the buried pipe, located between the fifth and seventh valves. By opening and closing the fifth, sixth, seventh, and eighth valves in the second valve station, the flow of the pipelines can be controlled, thereby enabling the switching of the series or parallel connection between the heat network return water replenishment component and the ground source heat pump component, and thus switching the heating mode.

[0010] The buried water supply pipe is equipped with a temperature monitoring component for monitoring the water supply temperature. The temperature monitoring component is located between the buried pipe and the second valve station. The heating system's operating mode is switched based on the buried water supply temperature. The monitored temperature data is transmitted to the controller, which controls the opening and closing of each valve and the start and stop of each circulating pump.

[0011] The aforementioned heat network return water replenishment component includes a first heat exchanger. The water supply pipe on the heat absorption side of the first heat exchanger is connected to the heat network return water network through a twelfth valve and a heat network return water circulation pump. The return water pipe on the heat absorption side of the first heat exchanger is connected to the heat network return water network through an eleventh valve. The water supply pipe and return water pipe on the heat release side of the first heat exchanger are connected to a first valve station.

[0012] The heat storage assembly includes a hot water storage tank. The heat absorption side of the hot water storage tank absorbs heat from the return water network of the heating network through a second heat exchanger, and the heat release side of the hot water storage tank is connected to a first valve station through a third heat exchanger. The switching between heating network heat supply and hot water storage tank heat supply modes is achieved by controlling the opening and closing of valves in the first valve station.

[0013] A method for operating the municipal heating network return water and ground source heat pump coupled heating system involves real-time monitoring of the water supply temperature of the buried pipe, and switching the system operation mode via a first valve station and a second valve station based on the water supply temperature of the buried pipe. Operating Mode 1: If the water supply temperature of the buried pipe is greater than 12℃, the heating supply of the heat network return water replenishment component and the heat storage component will be cut off through the second valve station, and the user will be heated only by the ground source heat pump component; at the same time, the heat storage component will recover the waste heat of the return water in the heat network return water pipe network. Operating Mode 2: If the water supply temperature on the buried pipe side is in the range of 7℃~12℃, the first valve station and the second valve station will switch to the parallel operation of the heat network return water replenishment component and the ground source heat pump component to jointly provide heat to users. Operating Mode 3: If the water supply temperature on the buried pipe side is lower than 7℃, the system switches to the series operation of the heat network return water replenishment component and the ground source heat pump component through the first and second valve stations. The water in the buried pipe supply pipe is heated in stages by the heat network return water replenishment component. After the water supply temperature is increased, the ground source heat pump component provides heat to the user.

[0014] In operating mode one, the underground circulating pump is started to deliver underground pipe-side water supply at a temperature of 10℃~15℃ to the evaporator; after the medium absorbs the heat from the underground pipe-side water supply in the evaporator, it is compressed and heated by the compressor and enters the condenser to release heat; the user-side circulating water pump is started to deliver the high-temperature water supply from the condenser outlet to the user for heating.

[0015] In operation mode two, when the water supply temperature on the buried pipe side is in the range of 7℃~12℃, and the return water volume of the heating network is insufficient, or during the emergency shutdown of the heating network or expansion and maintenance, the first valve station and the second valve station are switched to the parallel operation of the heat storage component and the ground source heat pump component to jointly supply heat to users.

[0016] In operation mode three, when the water supply temperature on the buried pipe side is below 7°C, and the return water volume of the heating network is insufficient, or during the emergency shutdown or expansion and maintenance of the heating network, the system switches to the series operation of the heat storage component and the ground source heat pump component through the first valve station and the second valve station. The water in the buried pipe supply pipe is heated in stages by the heat storage component. After the water supply temperature is increased, the ground source heat pump component supplies heat to the user.

[0017] The beneficial effects of this invention are as follows: By coordinating the operation of municipal heating network return water with a ground source heat pump system, waste heat from the return water can be effectively recovered, increasing the temperature difference between the supply and return water, significantly improving system energy efficiency, and reducing energy waste. Simultaneously, by using a series connection to provide cascade heating for the buried pipe water supply, the problem of soil thermal imbalance is effectively alleviated, ensuring the stable operation of the ground source heat pump under low-temperature conditions. The addition of a heat storage tank further enhances the system's ability to regulate and maintain heat supply during replenishment. Test results show that the adopted heat storage device has good insulation performance and low heat loss, effectively maintaining the heat storage effect, thereby improving the continuity and reliability of system operation, and making it suitable for energy-saving renovation and widespread application of existing heating facilities.

[0018] Energy utilization efficiency is significantly improved: by recovering the low-grade waste heat of 30℃~50℃ from the municipal heating network return water, the amount of waste heat wasted each year can be reduced; at the same time, the temperature difference between the supply and return water of the municipal heating network increases under the series operation mode, the heat transmission capacity of the heating network pipeline is improved, and the need for heating network expansion and renovation is reduced.

[0019] Enhanced system stability: By using 7℃ and 12℃ as the critical temperature points on the buried pipe side and dynamically switching between three operating modes, the COP value of the ground source heat pump unit can be avoided due to low temperature water supply, thus ensuring stable heating efficiency.

[0020] Improved reliability of emergency heating: The heat storage component can store the residual heat in the return water of the municipal heating network, enabling seamless emergency heating in the event of a heating network failure or insufficient return water volume, avoiding heating interruptions and reducing fluctuations in indoor temperature for users. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a thermal storage and synergistic heating system that couples municipal heating network return water with a ground source heat pump according to the present invention. Figure 2 Schematic diagram of standalone heating provided by ground source heat pump; Figure 3 Schematic diagram of parallel heating supply using municipal heating network return water coupled with ground source heat pumps; Figure 4 Schematic diagram of a municipal heating network return water coupled with a ground source heat pump in series for heating; Figure 5 Schematic diagram of parallel heating supply using a ground source heat pump coupled with thermal storage components; Figure 6 Schematic diagram of a series heating system using a ground source heat pump coupled with a thermal storage component for supplemental heating. Figure 7 A schematic diagram of the heat storage components for recovering waste heat from the municipal heating network return water.

[0023] In the diagram: 1. Heating network return water pipe network, 2. Heating network return water circulation pump, 3. First circulation pump, 4. Second circulation pump, 5. Hot water storage tank, 6. Buried side circulation pump, 7. User side circulation pump, 8. Third circulation pump, 9. First valve station, 10. Second valve station, 11. First heat exchanger, 12. Second heat exchanger, 13. Buried pipe, 14. Third heat exchanger; 101. First valve, 102. Second valve, 103. Third valve, 104. Fourth valve, 105. Fifth valve, 106. Sixth valve, 107. Seventh valve, 108. Eighth valve, 109. Ninth valve, 110. Tenth valve, 111. Eleventh valve, 112. Twelfth valve, 113. Thirteenth valve, 114. Fourteenth valve, 115. Fifteenth valve, 116. Sixteenth valve, 117. Seventeenth valve, 118. Eighteenth valve. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1, such as Figure 1As shown, a municipal heating network return water coupled with a ground source heat pump heating system includes a heating network return water replenishment component, a heat storage component, and a ground source heat pump component. The heating network return water replenishment component and the heat storage component are respectively connected to the heating network return water pipeline 1. The heating network return water replenishment component and the heat storage component are arranged in parallel. The heating network return water replenishment component or the heat storage component supplies heat to users through a first valve station 9 and a second valve station 10 in sequence. The ground source heat pump component supplies heat to users through the second valve station 10. The buried pipe 13 in the heating network return water replenishment component and the ground source heat pump component can be switched between parallel or series connection through the second valve station 10; or the buried pipe 13 in the heat storage component and the ground source heat pump component can be switched between parallel or series connection through the second valve station 10. The buried pipe 13 includes multiple parallel U-shaped pipes. The U-shaped pipe is buried in the soil; the first valve station 9 switches the heating network return water replenishment component to supply heat to the user or the heat storage component to supply heat to the user, so as to achieve seamless emergency heat replenishment when the heating network fails or the return water volume is insufficient, avoid heating interruption, and reduce the fluctuation of indoor temperature of the user.

[0026] In addition, the municipal heating network return water replenishment components and the ground source heat pump components work together to effectively recover waste heat from the return water, increase the temperature difference between the supply and return water, significantly improve system energy efficiency, and reduce energy waste. At the same time, by using a series connection to provide cascade heating for the buried pipe water supply, the problem of soil thermal imbalance is effectively alleviated, ensuring the stable operation of the ground source heat pump under low-temperature conditions.

[0027] Furthermore, the ground source heat pump assembly also includes an evaporator and a condenser. The water supply and return pipes of the buried pipe 13 are connected to the evaporator. A compressor is installed between the evaporator and the condenser. After absorbing heat, the heat exchange medium in the evaporator is compressed and heated by the compressor, and then enters the condenser to release heat. The condenser then supplies heat to the user. This process completes the efficient temperature raising and heat delivery from the low-grade heat source on the buried side.

[0028] Furthermore, the second valve station 10 includes a first pipeline, a second pipeline, and a third pipeline. The first pipeline connects the water supply pipe at the output end of the first valve station 9 and the water supply pipe of the buried pipe 13. The second pipeline connects the return water pipe at the output end of the first valve station 9 and the water supply pipe of the buried pipe 13. The third pipeline connects the return water pipe at the output end of the first valve station 9 and the return water pipe of the buried pipe 13. A fifth valve 105 is provided on the first pipeline, a seventh valve 107 is provided on the second pipeline, an eighth valve 108 is provided on the third pipeline, and a sixth valve 106 is provided on the water supply pipe of the buried pipe 13. The sixth valve 106 is located between the fifth valve 105 and the seventh valve 107. By switching the fifth valve 105, sixth valve 106, seventh valve 107, and eighth valve 108 in the second valve station 10, the on / off state of the pipeline can be regulated, thereby enabling the switching of the series or parallel connection between the heating network return water replenishment component and the ground source heat pump component, and thus switching the heating mode. Specifically, when the fifth valve 105, sixth valve 106, and seventh valve 107 are open and the eighth valve 108 is closed, the heating network return water replenishment component and the ground source heat pump component are connected in parallel for heating; when the fifth valve 105 and eighth valve 108 are open and the sixth valve 106 and seventh valve 107 are closed, the heating network return water replenishment component and the ground source heat pump component are connected in series for heating.

[0029] Furthermore, a temperature monitoring component is installed on the water supply pipe of the buried pipe 13 to monitor the water supply temperature of the buried pipe 13. The temperature detection component is located between the buried pipe 13 and the second valve station 10. The working mode of the heating system is switched based on the water supply temperature of the buried pipe 13. The monitored temperature data is transmitted to the controller, which controls the opening and closing of each valve and the start and stop of each circulating pump.

[0030] Furthermore, the heat network return water replenishment component includes a first heat exchanger 11. The supply pipe on the heat absorption side of the first heat exchanger 11 is connected to the heat network return water network 1 through the twelfth valve 112 and the heat network return water circulation pump 2. The return water pipe on the heat absorption side of the first heat exchanger 11 is connected to the heat network return water network 1 through the eleventh valve 111. The supply and return water pipes on the heat release side of the first heat exchanger 11 are connected to the first valve station 9. The first heat exchanger 11 is a plate heat exchanger. The heat network return water circulation pump 2 can drive the flow of the medium when it starts. Specifically, the heat network return water network 1 includes a primary network supply water pipe and a primary network return water pipe. The heat network return water circulation pump 2 pushes the water in the primary network return water pipe to the first heat exchanger 11. After heat exchange in the first heat exchanger 11, the water flows back to the primary network return water pipe. The water supply pipe on the heat dissipation side of the first heat exchanger 11 is connected to the third valve 103 in the first valve station 9, and the water return pipe on the heat dissipation side of the first heat exchanger 11 is connected to the fourth valve 104 in the first valve station 9.

[0031] Example 2, based on Example 1, provides a municipal heating network return water coupled with a ground source heat pump heating system. The heat storage component includes a hot water storage tank 5. The heat absorption side of the hot water storage tank 5 absorbs heat from the heating network return water pipe network 1 through a second heat exchanger 12, and the heat release side of the hot water storage tank 5 is connected to a first valve station 9 through a third heat exchanger 14. The second heat exchanger 12 is a plate heat exchanger. The supply and return water pipes on the heat release side of the second heat exchanger 12 are both connected to the hot water storage tank 5. The supply water pipe on the heat release side of the second heat exchanger 12 is sequentially equipped with a third circulating pump 8, a thirteenth valve 113, and a fourteenth valve 114, and the return water pipe on the heat release side of the second heat exchanger 12 is sequentially equipped with a seventeenth valve 117 and a sixteenth valve 116.

[0032] In addition, the eighteenth valve 118 is connected to the sixteenth valve 116 on the water supply pipe on the heat absorption side of the third heat exchanger 14. The second circulating pump 4 and the fifteenth valve 115 are sequentially installed on the return water pipe on the heat absorption side of the third heat exchanger 14. The fifteenth valve 115 is connected to the fourteenth valve 114. The water supply pipe on the heat release side of the third heat exchanger 14 is connected to the second valve 102 in the first valve station 9. The return water pipe on the heat release side of the third heat exchanger 14 is connected to the first valve 101 in the first valve station 9.

[0033] Example 3, based on Example 2, describes a method for operating a municipal heating network return water and ground source heat pump coupled heating system. This method involves real-time monitoring of the water supply temperature of the buried pipe 13, and switching the system operating mode via the first valve station 9 and the second valve station 10 based on the water supply temperature of the buried pipe 13. Operating Mode 1: If the water supply temperature of the buried pipe 13 is greater than 12℃, the heating supply to the heat network return water replenishment component and the heat storage component will be cut off through the second valve station 10, and only the ground source heat pump component will supply heat to the user; at the same time, the heat storage component will recover the waste heat of the return water in the heat network return water pipe network 1; such as Figure 2 As shown, the fifth valve 105, the seventh valve 107, and the eighth valve 108 in the second valve station 10 are closed, the sixth valve 106 is opened, and the underground side circulation pump 6 is started to deliver underground pipe side water with a temperature of 10℃~15℃ to the evaporator; after the medium absorbs the heat of the underground pipe side water in the evaporator, it is compressed and heated by the compressor and enters the condenser to release heat; the user side circulation water pump 7 is started to deliver the high-temperature water from the condenser outlet to the user for heating.

[0034] In addition, such as Figure 7 As shown, the ninth valve 109, the tenth valve 110, the thirteenth valve 113, the fourteenth valve 114, the sixteenth valve 116 and the seventeenth valve 117 are opened, the third circulation pump 8 is started, and the second heat exchanger 12 absorbs the waste heat of the return water in the heat network return water pipe network 1 and sends it to the hot water storage tank 5 for storage.

[0035] Operating Mode 2: If the water supply temperature on the buried pipe side is between 7℃ and 12℃, the system switches to parallel operation of the heat network return water replenishment component and the ground source heat pump component via the first valve station 9 and the second valve station 10 to jointly supply heat to users; Figure 3 As shown, the first valve 101 and the second valve 102 in the first valve station 9 and the seventh valve 107 in the second valve station 10 are closed. The third valve 103 and the fourth valve 104 in the first valve station 9 and the fifth valve 105, the sixth valve 106, and the eighth valve 108 in the second valve station 10 are opened. The buried side circulation pump 6 and the first circulation pump 3 are started. The water that has been heat-exchanged by the first heat exchanger 11 flows into the water supply pipe of the buried pipe 13. The heat recovered by the heat network return water replenishment component is mixed with the heat output from the buried pipe 13, so that the supply water temperature entering the evaporator is maintained above 12°C, thereby ensuring that the unit operates under high-temperature efficiency. This effectively alleviates the performance degradation problem caused by single heat extraction from the ground source side, improves the overall heating capacity of the system, and further promotes the deep utilization of soil thermal energy while maintaining unit efficiency.

[0036] Operating Mode 3: If the water supply temperature on the buried pipe side is lower than 7℃, the system switches to a series operation of the heat network return water replenishment component and the ground source heat pump component via the first valve station 9 and the second valve station 10. The water in the buried pipe 13 is heated in stages by the heat network return water replenishment component, and after the water supply temperature is increased, the ground source heat pump component provides heat to the user. Figure 4 As shown, the first valve 101 and the second valve 102 in the first valve station 9, and the sixth valve 106 and the eighth valve 108 in the second valve station 10 are closed. The third valve 103 and the fourth valve 104 in the first valve station 9, and the fifth valve 105 and the seventh valve 107 in the second valve station 10 are opened. The buried side circulation pump 6 and the first circulation pump 3 are started. The water output from the buried pipe 13 enters the heat network return water replenishment component, absorbs the residual heat in the return water, and after secondary heating by the heat network return water replenishment component, flows back to the water supply pipe of the buried pipe 13, and then into the evaporator. The water in the buried pipe 13 undergoes staged heating through the heat network return water replenishment component, raising the supply water temperature to 12℃, thereby providing a heat source for the evaporator in the ground source heat pump component. This mode significantly reduces the heat network return water temperature. Through this adjustment, the efficient operation of the ground source heat pump can be maintained, while enhancing the heat transfer capacity of the entire heating system and further improving the deep utilization of soil thermal energy.

[0037] Example 4, based on Example 3, describes a working method for a municipal heating network return water and ground source heat pump coupled heating system. In operation mode two, when the water supply temperature on the buried pipe side is between 7℃ and 12℃, and the heating network return water volume is insufficient, or during emergency shutdown or expansion maintenance of the heating network, the system switches to parallel operation of the heat storage component and the ground source heat pump component through the first valve station 9 and the second valve station 10 to jointly supply heat to users. Figure 5As shown, the third valve 103 and the fourth valve 104 in the first valve station 9 and the seventh valve 107 in the second valve station 10 are closed. The first valve 101, the second valve 102, the fifth valve 105, the sixth valve 106, the eighth valve 108, the fourteenth valve 114, the fifteenth valve 115, the sixteenth valve 116, and the eighteenth valve 118 are opened. The buried side circulation pump 6, the first circulation pump 3, and the second circulation pump 4 are started. The heat from the hot water storage tank 5 is exchanged through the third heat exchanger 14 and then introduced into the water supply pipe of the buried pipe 13. The heat stored in the hot water storage tank 5 is mixed with the heat output from the buried pipe 13, maintaining the water supply temperature entering the evaporator above 12℃, thus ensuring the unit operates under high-efficiency temperature conditions. This provides seamless emergency heating in case of heating network failure or insufficient return water, avoiding heating interruptions and reducing indoor temperature fluctuations for users.

[0038] Example 5, based on Example 3, describes a working method for a municipal heating network return water and ground source heat pump coupled heating system. In operation mode three, when the water supply temperature on the buried pipe side is below 7°C, and the heating network return water volume is insufficient, or during emergency shutdown or expansion maintenance of the heating network, the system switches from the first valve station 9 to the second valve station 10, where the heat storage component and the ground source heat pump component operate in series. The water in the buried pipe 13 supply pipe undergoes cascade heating through the heat storage component, and after the supply water temperature is increased, the ground source heat pump component supplies heat to the user. For example... Figure 6 As shown, the third valve 103 and the fourth valve 104 in the first valve station 9 and the sixth valve 106 and the eighth valve 108 in the second valve station 10 are closed. The first valve 101 and the second valve 102 in the first valve station 9 and the fifth valve 105 and the seventh valve 107 in the second valve station 10 are opened. The fourteenth valve 114, the fifteenth valve 115, the sixteenth valve 116, and the eighteenth valve 118 on the heat absorption side of the third heat exchanger 14 are opened. The underground circulation pump 6, the first circulation pump 3, and the second circulation pump 4 are started. The water output from the underground pipe 13 enters the heat storage component, absorbs the heat stored in the hot water storage tank 5, and after secondary heating by the heat storage component, flows back to the water supply pipe of the underground pipe 13 and then into the evaporator. The water in the underground pipe 13 is heated in stages by the heat storage component, raising the supply water temperature to 12°C, thereby providing a heat source for the evaporator in the ground source heat pump component. This mode significantly reduces the return water temperature of the heating network.

[0039] 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 within the protection scope of the present invention.

Claims

1. A municipal heating network return water coupled with a ground source heat pump heating system, characterized in that, It includes a heat network return water replenishment component, a heat storage component and a ground source heat pump component. The heat network return water replenishment component and the heat storage component are respectively connected to the heat network return water pipeline (1). The heat network return water replenishment component and the heat storage component are arranged in parallel. The heat network return water replenishment component or the heat storage component supplies heat to users through the first valve station (9) and the second valve station (10) in sequence. The ground source heat pump component supplies heat to users through the second valve station (10). The buried pipe (13) in the heat network return water replenishment component and the ground source heat pump component are switched in parallel or in series through the second valve station (10); or the buried pipe (13) in the heat storage component and the ground source heat pump component are switched in parallel or in series through the second valve station (10). The buried pipe (13) includes multiple parallel U-shaped pipes.

2. The municipal heating network return water and ground source heat pump coupled heating system according to claim 1, characterized in that, The ground source heat pump assembly also includes an evaporator and a condenser. The water supply pipe and return pipe of the buried pipe (13) are connected to the evaporator. A compressor is provided between the evaporator and the condenser. After absorbing heat, the heat exchange medium in the evaporator is compressed and heated by the compressor, and then enters the condenser to release heat. The condenser supplies heat to the user.

3. The municipal heating network return water and ground source heat pump coupled heating system according to claim 2, characterized in that, The second valve station (10) includes a first pipeline, a second pipeline and a third pipeline. The first pipeline connects the water supply pipe at the output end of the first valve station (9) and the water supply pipe of the underground pipe (13). The second pipeline connects the return water pipe at the output end of the first valve station (9) and the water supply pipe of the underground pipe (13). The third pipeline connects the return water pipe at the output end of the first valve station (9) and the return water pipe of the underground pipe (13). A fifth valve (105) is provided on the first pipeline, a seventh valve (107) is provided on the second pipeline, an eighth valve (108) is provided on the third pipeline, and a sixth valve (106) is provided on the water supply pipe of the underground pipe (13). The sixth valve (106) is located between the fifth valve (105) and the seventh valve (107).

4. The municipal heating network return water and ground source heat pump coupled heating system according to any one of claims 1 to 3, characterized in that, The water supply pipe of the underground pipe (13) is equipped with a temperature monitoring component for monitoring the water supply temperature of the underground pipe (13). The temperature detection component is located between the underground pipe (13) and the second valve station (10).

5. The municipal heating network return water and ground source heat pump coupled heating system according to claim 4, characterized in that, The heat exchanger return water replenishment component includes a first heat exchanger (11). The water supply pipe on the heat absorption side of the first heat exchanger (11) is connected to the heat exchanger return water network (1) through the twelfth valve (112) and the heat exchanger return water circulation pump (2). The return water pipe on the heat absorption side of the first heat exchanger (11) is connected to the heat exchanger return water network (1) through the eleventh valve (111). The water supply pipe and return water pipe on the heat release side of the first heat exchanger (11) are connected to the first valve station (9).

6. The municipal heating network return water and ground source heat pump coupled heating system according to claim 5, characterized in that, The heat storage component includes a hot water storage tank (5). The heat absorption side of the hot water storage tank (5) absorbs heat from the return water network (1) of the heating network through a second heat exchanger (12). The heat release side of the hot water storage tank (5) is connected to the first valve station (9) through a third heat exchanger (14).

7. A method for operating a municipal heating network return water coupled heating system with a ground source heat pump as described in any one of claims 1 to 6, characterized in that, The water supply temperature of the buried pipe (13) is monitored in real time, and the system operation mode is switched through the first valve station (9) and the second valve station (10) according to the water supply temperature of the buried pipe (13): Operating mode 1: If the water supply temperature of the buried pipe (13) is greater than 12℃, the heating network return water replenishment component and the heat storage component will be cut off through the second valve station (10), and the user will be heated only through the ground source heat pump component; at the same time, the heat storage component will recover the waste heat of the return water in the heat network return water pipe network (1). Operating mode 2: If the water supply temperature on the buried pipe side is in the range of 7℃~12℃, the first valve station (9) and the second valve station (10) are switched to the parallel operation of the heat network return water replenishment component and the ground source heat pump component to jointly supply heat to users; Operating mode 3: If the water supply temperature on the buried pipe side is lower than 7℃, the first valve station (9) and the second valve station (10) are switched to the series operation of the heat network return water replenishment component and the ground source heat pump component. The water in the buried pipe (13) water supply pipe is heated in stages by the heat network return water replenishment component. After the water supply temperature is increased, the ground source heat pump component will then supply heat to the user.

8. The working method of the municipal heating network return water and ground source heat pump coupled heating system according to claim 7, characterized in that, In operating mode one, the underground side circulation pump (6) is started to deliver the underground pipe side water supply to the evaporator; after the medium absorbs the heat of the underground pipe side water supply in the evaporator, it is compressed and heated by the compressor and enters the condenser to release heat; the user side circulation water pump (7) is started to deliver the high temperature water supply from the condenser outlet to the user for heating.

9. The working method of the municipal heating network return water and ground source heat pump coupled heating system according to claim 7, characterized in that, In operation mode 2, when the water supply temperature on the buried pipe side is in the range of 7℃~12℃, and the heat network return water volume is insufficient, or during the emergency shutdown or expansion maintenance of the heat network, the first valve station (9) and the second valve station (10) are switched to the parallel operation of the heat storage component and the ground source heat pump component to jointly supply heat to the user.

10. The working method of the municipal heating network return water and ground source heat pump coupled heating system according to claim 7, characterized in that, In operation mode 3, when the water supply temperature on the buried pipe side is below 7°C, and the heat network return water volume is insufficient, or during the emergency shutdown or expansion maintenance of the heat network, the first valve station (9) and the second valve station (10) are switched to the series operation of the heat storage component and the ground source heat pump component. The water in the buried pipe (13) water supply pipe is heated in stages by the heat storage component. After the water supply temperature is increased, the ground source heat pump component supplies heat to the user.

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