A decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange.

Abstract

This invention discloses a centralized heat recovery system for decentralized exhaust air source heat pumps based on water-to-air heat exchange, belonging to the technical field of heat recovery systems. It includes an exhaust air collection module, a water-to-air heat exchange module, a heat pump unit, and a heat recovery and utilization module. The exhaust air collection module is connected to the water-to-air heat exchange module via a central duct. The water-to-air heat exchange module is connected to the heat pump unit via a water circulation pipeline. The heat pump unit is connected to the heat recovery and utilization module via a power supply pipe. This invention, by incorporating an exhaust air collection module, achieves centralized collection of decentralized exhaust air from various functional areas of a building and precise screening of high-quality hot air. This avoids the decrease in heat quality caused by mixing low-temperature and high-temperature exhaust air, improving the targeting and effectiveness of heat recovery.

Description

Technical Field

[0001] This invention relates to the field of heat recovery system technology, specifically to a decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange. Background Technology

[0002] In existing buildings, the exhaust air generated by functional areas such as office areas and equipment rooms is usually directly discharged to the outside, containing a large amount of waste heat. In particular, the exhaust air from air conditioning in summer and the exhaust air from equipment heat dissipation in winter are not effectively utilized, resulting in energy waste. Currently, waste heat recovery mostly adopts decentralized devices, such as single exhaust heat exchangers. Traditional equipment can only recover the heat of exhaust air from a single area, making it difficult to coordinate decentralized exhaust air with different temperatures and flow rates. Moreover, traditional equipment has low heat exchange efficiency, and the mixing of low-temperature exhaust air with high-temperature exhaust air will significantly reduce the quality of heat recovery, resulting in a decrease in the utilization value of recovered heat.

[0003] Patent CN104848597B discloses a geothermal recovery system, which achieves energy conservation and improves economic efficiency.

[0004] The aforementioned patent utilizes a free, low-grade heat source to drive an absorption heat pump, which can reduce the installed capacity of centrifugal heat pumps. By combining absorption heat pumps and centrifugal heat pumps, power consumption can be reduced, energy can be saved, and economic efficiency can be improved. However, there is still room for optimization in terms of heat recovery and gradient utilization of decentralized exhaust air.

[0005] Therefore, this application proposes a centralized heat recovery system for decentralized exhaust heat pumps that enables centralized recovery and cascade utilization of heat from decentralized exhaust air through water-to-air heat exchange. Summary of the Invention

[0006] The purpose of this invention is to provide a decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange, in order to solve the technical problems mentioned in the background art, such as the difficulty of traditional equipment in coordinating decentralized exhaust with different temperatures and flow rates and low heat exchange efficiency.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a decentralized exhaust source heat pump centralized heat recovery system based on water-to-air heat exchange, comprising an exhaust collection module, a water-to-air heat exchange module, a heat pump unit, and a heat recovery and utilization module. The exhaust collection module is connected to the water-to-air heat exchange module through a converging air duct. The water-to-air heat exchange module is connected to the heat pump unit through a water circulation pipeline. The heat pump unit is connected to the heat recovery and utilization module through a power supply pipe.

[0008] The exhaust gas acquisition module includes a distributed exhaust hood, an air volume regulation component, and a collection duct.

[0009] The distributed exhaust hoods are installed at the exhaust outlets of different functional areas of the building. A filter screen is installed at the inlet of the distributed exhaust hood. The air volume regulation component includes a temperature sensor and an electric air valve. The temperature sensor is used to detect the exhaust temperature, and the opening degree of the electric air valve is adjusted according to the change of exhaust temperature. One end of the collection duct is connected to each distributed exhaust hood, and the other end is connected to the air-side inlet of the heat exchanger, which is used to centrally transport the dispersed exhaust air to the heat exchanger.

[0010] Preferably, the exhaust gas collection module is connected to the water-to-air heat exchange module through a converging air duct;

[0011] The water-to-air heat exchange module includes a heat exchanger, a water pump, and a water circulation pipeline;

[0012] The water circulation pipeline includes an outlet pipe and a return pipe. The heat exchanger is equipped with an air-side inlet, an air-side outlet, a water-side inlet, and a water-side outlet. The air-side inlet of the heat exchanger is connected to the main air duct, and the air-side outlet of the heat exchanger is used to discharge the heat-exchanged gas. The water-side inlet and outlet of the heat exchanger are connected to the water circulation pipeline. A water pump is installed in the water circulation pipeline. The water pump drives the circulating water to flow between the heat exchanger and the evaporator of the heat pump unit, so that the circulating water exchanges heat with the exhaust air on the air side in the heat exchanger. The air side and water side of the heat exchanger are isolated from each other, and the exhaust air and circulating water transfer heat through the heat exchanger.

[0013] Preferably, the water-to-air heat exchange module is connected to the heat pump unit via a water circulation pipeline;

[0014] A heat pump unit consists of a compressor, an evaporator, and a condenser;

[0015] The compressor, evaporator, and condenser are connected in sequence through pipelines to form a closed loop. The evaporator is equipped with a water-side inlet, a water-side outlet, an inlet, and an outlet. The water-side inlet of the evaporator is connected to the outlet pipe of the water circulation pipeline, and the water-side outlet of the evaporator is connected to the return pipe of the water circulation pipeline to form a circulating water circuit. The evaporator outlet is connected to the compressor inlet to allow low-pressure, low-temperature refrigerant vapor to enter the compressor. The compressor outlet is connected to the condenser inlet to send high-pressure, high-temperature refrigerant vapor into the condenser. The condenser outlet is connected to the evaporator inlet to throttle and reduce the pressure of the condensed refrigerant liquid before it is fed into the evaporator to complete the circulation.

[0016] Preferably, the condenser is connected to the heat recovery module via a power supply pipe, and the heat recovery module is connected to the heat pump unit via a recovery pipe to form a circulation pipeline;

[0017] The heat recovery and utilization module includes a district heating station, energy-consuming equipment, and a domestic hot water storage tank;

[0018] The condenser has a heat carrier inlet and a heat carrier outlet. The heat carrier outlet is connected to the input end of the district heating station through a power supply pipeline. The district heating station is equipped with a reversing valve group to control the flow of heat carrier to the energy-consuming equipment and the domestic hot water storage tank. The output end of the district heating station is connected to the energy-consuming equipment and the domestic hot water storage tank through branch pipelines. The energy-consuming equipment has heat exchange components inside to exchange heat with the heat carrier. The heat exchange components in the domestic hot water storage tank are in contact with the heat carrier through the pipe wall. The return flow from the energy-consuming equipment and the domestic hot water storage tank is collected and connected to the heat carrier inlet of the condenser through a recovery pipe.

[0019] Preferably, the circulating water in the evaporator forms an independent circulation system. The circulating water is sent to the water-side inlet of the evaporator through the outlet pipe of the water-to-air heat exchange module. After the circulating water completes heat exchange with the refrigerant in the evaporator, it is driven by a water pump to flow from the water-side outlet of the evaporator back to the heat exchanger of the water-to-air heat exchange module through the return water pipe. The heat carrier of the condenser forms another independent circulation system. The heat carrier enters the regional heating station of the heat recovery and utilization module through the energy supply pipeline from the heat carrier outlet of the condenser. After being distributed by the reversing valve group, it flows into the energy-consuming equipment and the domestic hot water storage tank. After releasing heat, the heat carrier is collected and returned to the heat carrier inlet of the condenser through the recovery pipe. The circulating water system of the evaporator is connected to the water-to-air heat exchange module and circulates only between the two. The heat carrier circulation system of the condenser is connected to the heat recovery and utilization module and circulates only between the two. The two circulation systems are independent of each other.

[0020] Preferably, the distributed exhaust hoods are installed at the exhaust outlets of each functional area of ​​the building. The distributed exhaust hoods are funnel-shaped and have an inlet end and an outlet end. The inlet end is equipped with a removable filter screen to intercept particulate matter in the exhaust air. The outlet end of the distributed exhaust hood is connected to the main exhaust duct through a branch duct. The airflow regulation component includes a temperature sensor and an electric damper. The temperature sensor is installed in the branch duct at the outlet end of the distributed exhaust hood to detect the temperature of the exhaust air flowing through it. The electric damper is installed in the branch duct to adjust the valve opening. Each branch duct of the distributed exhaust hood is equipped with an airflow regulation component. All branch ducts are connected to the inlet of the main exhaust duct after being combined. The outlet of the main exhaust duct is connected to the air-side inlet of the heat exchanger in the water-to-air heat exchange module.

[0021] Preferably, the directional valve assembly includes a main directional valve, a branch control valve, and a signal receiving unit;

[0022] The main reversing valve is installed on the main pipeline between the input and output ends of the heating station to switch the main direction of the heat carrier. The branch control valves are connected to the branch pipelines of the energy-consuming equipment and the domestic hot water storage tank to control the opening and closing of each branch. The signal receiving unit is electrically connected to each valve to receive external control signals and drive the valves to operate, which is used for switching and distributing between different energy consumption paths.

[0023] Preferably, one end of the outlet pipe of the water circulation pipeline is connected to the water-side outlet of the heat exchanger in the water-to-air heat exchange module, and the other end is connected to the water-side inlet of the evaporator of the heat pump unit through a flange. One end of the return pipe of the water circulation pipeline is connected to the water-side outlet of the evaporator, and the other end is connected to the water-side inlet of the heat exchanger.

[0024] Preferably, the temperature sensor is connected to the control module via a transmission line;

[0025] The control module includes a controller and transmission lines;

[0026] The controller is connected to the temperature sensors and electric air valves in the branch ducts of each distributed exhaust hood via transmission lines. After receiving the temperature signal, the controller outputs control commands to the electric air valves to adjust the valve opening. The controller is also connected to the signal receiving unit via transmission lines to transmit reversing and flow control signals to the signal receiving unit.

[0027] Preferably, the controller is connected to the water pump via a transmission line, which is connected to the drive motor in the water pump. The controller outputs start, stop, and speed control signals to the drive motor. The controller is also connected to the compressor via a transmission line, which is connected to the frequency converter in the compressor. The controller adjusts the operating frequency of the compressor through the frequency converter.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. This invention, by designing an exhaust collection module and a control module, realizes the centralized collection of dispersed exhaust air from various functional areas of a building and the precise screening of high-grade hot air. It avoids the decrease in heat grade caused by the mixing of low-temperature exhaust air and high-temperature exhaust air, improves the targeting and effectiveness of hot air recovery, and solves the problem that existing decentralized devices can only recover exhaust air from a single area and cannot coordinate and control exhaust air at different temperatures.

[0030] 2. This invention, by designing a water-to-air heat exchange module, achieves efficient and isolated transfer of exhaust heat to circulating water, improving heat exchange efficiency while avoiding pollution of circulating water by exhaust pollutants, thus solving the problems of low efficiency and easy cross-contamination of media in traditional heat exchange devices.

[0031] 3. By installing a heat pump unit, this invention converts low-grade exhaust waste heat into high-grade usable heat energy, breaking through the environmental temperature limitation and enabling the system to operate stably under different climatic conditions. This solves the problems of traditional heat pumps being greatly affected by the environment and having unstable energy efficiency.

[0032] 4. This invention, through the design of a heat recovery and utilization module, realizes dynamic allocation based on heat demand. By coordinating with the control module through the reversing valve group, it matches the heating and domestic hot water demand, improves the flexibility and overall efficiency of heat recovery and utilization, and solves the problems of rigid heat allocation, supply and demand mismatch and single utilization scenario in traditional systems. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall process of the present invention;

[0034] Figure 2 This is a schematic diagram of the exhaust air collection module of the present invention;

[0035] Figure 3 This is a schematic diagram of the circulating water flow process of the present invention;

[0036] Figure 4 This is a schematic diagram of the refrigerant circulation process of the present invention;

[0037] Figure 5 This is a schematic diagram of the heat carrier circulation process of the present invention; Detailed Implementation

[0038] 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.

[0039] Please see Figure 1 and Figure 2 The present invention provides an embodiment of a decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange. The distributed exhaust hoods are set at the exhaust outlets of different functional areas of the building. The inlet is equipped with a filter screen. The opening degree of the electric air valve is adjusted according to the exhaust temperature. One end of the collection air duct is connected to each distributed exhaust hood, and the other end is connected to the air-side inlet of the heat exchanger, so as to centrally transport the decentralized exhaust air to the heat exchanger.

[0040] Temperature sensors are installed in the branch ducts at the outlet of the distributed exhaust hood to detect the temperature of the exhaust air flowing through them. Electric air valves are installed in the branch ducts to adjust the valve opening. Each branch duct of the distributed exhaust hood is equipped with an airflow regulating component. All branch ducts are connected to the inlet of the main duct after being combined. The outlet of the main duct is connected to the air-side inlet of the heat exchanger in the water-to-air heat exchange module.

[0041] Furthermore, after the system starts, the controller of the control module first completes initialization and sends a start signal to the temperature sensor in each distributed exhaust hood branch duct through the transmission line, triggering the temperature sensor to enter the detection state. The temperature sensor collects the exhaust temperature in the branch duct in real time, such as the exhaust temperature in the office area and the exhaust temperature in the equipment room, and returns the temperature signal to the controller through the transmission line. The controller has a temperature threshold algorithm set inside, with a preset hot air recovery reference temperature of 25°C. When the temperature signal received by the controller is higher than the reference value of 25°C, the controller determines that it is recyclable hot air.

[0042] The temperature threshold algorithm is the program logic in the control module used to determine whether exhaust air has recycling value. When the controller detects that the exhaust air temperature of a certain branch duct is greater than 30℃, the controller sends a fully open command to the electric damper of that branch duct. The electric damper controls the valve plate opening to adjust to 100% to collect high-temperature exhaust air to the maximum extent. When the controller detects that the exhaust air temperature of a certain branch duct is between 25℃ and 30℃, it closes the range and sends a half-open command to the electric damper of that branch duct. The electric damper controls the valve plate opening to adjust to 50% to collect moderately. When the controller detects that the exhaust air temperature of a certain branch duct is lower than 25℃, the controller sends a close command to the electric damper of that branch duct. The electric damper controls the valve plate opening to close completely and stops collecting low-temperature exhaust air. Through real-time detection by the temperature sensor and dynamic adjustment of the electric damper, it is possible to accurately screen high-grade hot air, reduce the impact of low-temperature exhaust air on heat exchange efficiency, significantly reduce the energy consumption of the heat pump unit, and achieve efficient energy utilization.

[0043] Please see Figure 1 and Figure 3 The present invention provides an embodiment of a decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange. The water-side inlet of the evaporator is connected to the outlet pipe of the water circulation pipeline, and the water-side outlet of the evaporator is connected to the return pipe of the water circulation pipeline. The air-side inlet of the heat exchanger is connected to the exhaust air acquisition module through a combined air duct. The air-side outlet of the heat exchanger is used to discharge the heat-exchanged gas. The water-side inlet and outlet of the heat exchanger are connected to the water circulation pipeline. A water pump is installed in the water circulation pipeline. The water pump drives the circulating water to flow between the heat exchanger and the evaporator of the heat pump unit, so that the circulating water exchanges heat with the exhaust air on the air side in the heat exchanger. The air side and water side of the heat exchanger are isolated from each other. The exhaust air and circulating water transfer heat through the wall of the heat exchanger.

[0044] The circulating water is sent to the water-side inlet of the evaporator through the outlet pipe of the water-to-air heat exchange module. After the circulating water completes heat exchange with the refrigerant in the evaporator, it is driven by a water pump to flow back to the heat exchanger of the water-to-air heat exchange module through the return water pipe.

[0045] Furthermore, the hot air temperature after being filtered by the exhaust collection module is above 25°C. The hot air enters the heat exchanger through the converging air duct. The heat exchanger has a shell-and-tube structure with parallel heat exchange tubes inside. The outer wall of the heat exchange tubes is equipped with heat dissipation fins to increase the heat exchange area. A baffle is installed in the shell side to guide the hot air to flow evenly through all the heat exchange tubes. The heat exchange tubes are filled with circulating water. The outer side of the heat exchange tubes is a gas-side flow space. The gas side and water side are completely isolated by the tube wall. The hot air enters the shell side of the heat exchanger from the gas side inlet through the converging air duct. The hot air flows in a counter-current direction along the outer wall of the heat exchange tubes. The flow direction of the hot air is opposite to the flow direction of the circulating water in the heat exchange tubes. Finally, it is discharged from the gas side outlet. The circulating water enters the tube side from the water side inlet of the heat exchanger, flows through the inside of the heat exchange tubes, and then flows out from the water side outlet. It enters the evaporator of the heat pump unit through the water circulation pipeline.

[0046] When the system starts, the control module activates the water pump's drive motor, which in turn drives the circulating water at a stable flow rate of 1.5 m³ / h. 3 / h flows in the water circulation pipeline. The initial temperature of the circulating water is 15℃. The circulating water first enters the water side inlet of the heat exchanger. The hot air flowing in the tube side and shell side exchanges heat through the heat exchange tube wall. The heat of the hot air is transferred to the circulating water through the heat exchange tube wall, which raises the temperature of the circulating water. After the hot air releases heat, its temperature drops and it is discharged from the gas side outlet of the heat exchanger.

[0047] By using counter-current heat exchange of hot air, efficient heat transfer of the hot air can be ensured. Moreover, the independent air-side and water-side flow channels avoid direct contact between exhaust air and circulating water, preventing circulating water pollution. The recovery of hot air heat provides a stable medium-temperature heat source for the evaporator of the heat pump unit, further improving the energy efficiency of the system.

[0048] Please see Figure 1 and Figure 4 One embodiment of the present invention is a decentralized exhaust heat pump centralized heat recovery system based on water-to-gas heat exchange. The water-side inlet of the evaporator is connected to the outlet pipe of the water circulation pipeline, and the water-side outlet of the evaporator is connected to the return pipe of the water circulation pipeline to form a circulating water circuit. The outlet of the evaporator is connected to the inlet of the compressor to allow low-pressure, low-temperature refrigerant vapor to enter the compressor.

[0049] Furthermore, the circulating water that absorbs heat enters the evaporator through the water circulation pipeline. The circulating water flows in from the water-side inlet of the evaporator, which has a shell-and-tube structure. The circulating water exchanges heat with the liquid refrigerant in the shell side of the evaporator tube side. At this time, the refrigerant is in a low-pressure state, at 0.5 MPa. The refrigerant absorbs heat from the circulating water through the tube wall and evaporates from a liquid state to a gaseous state. After releasing heat, the temperature of the circulating water drops to about 15°C. It flows back to the water-to-gas heat exchange module from the water-side outlet through the return water pipe, realizing the heat transfer between the circulating water and the refrigerant. The waste heat carried by the exhaust air in the circulating water is transferred to the refrigerant, preparing for subsequent heat upgrades. At the same time, the circulating water can re-participate in heat exchange after cooling down, forming a closed-loop water circuit.

[0050] Please see Figure 1 and Figure 4 One embodiment of the present invention provides a decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange. The water-side inlet of the evaporator is connected to the outlet pipe of the water circulation pipeline, and the water-side outlet of the evaporator is connected to the return pipe of the water circulation pipeline to form a circulating water circuit. The evaporator outlet is connected to the compressor inlet to supply low-pressure, low-temperature refrigerant vapor to the compressor. The compressor outlet is connected to the condenser inlet to send high-pressure, high-temperature refrigerant vapor into the condenser. The condenser outlet is connected to the evaporator inlet to throttle and depressurize the condensed refrigerant liquid before inputting it into the evaporator to complete the circulation. The controller is connected to the compressor through a transmission line, which is connected to the frequency converter in the compressor. The controller adjusts the operating frequency of the compressor through the frequency converter.

[0051] Furthermore, the gaseous refrigerant at the evaporator outlet enters the compressor through pipelines. The controller starts the compressor through transmission lines. The compressor compresses the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant through mechanical work. The compression increases the temperature and pressure of the refrigerant, making the refrigerant temperature higher than the subsequent energy demand. The high-temperature, high-pressure refrigerant vapor enters the shell side of the condenser from the compressor outlet. At this time, the temperature of the high-temperature, high-pressure gaseous refrigerant is 80°C. It exchanges heat with the 50°C heat carrier in the tube side of the condenser. The heat carrier is water. After releasing heat, the high-temperature, high-pressure refrigerant condenses into a high-pressure liquid refrigerant. After absorbing heat, the temperature of the heat carrier rises to 60°C. It is then transported to the heat recovery module through the energy supply pipeline. The condenser transfers the high-grade heat carried by the refrigerant to the energy user to meet the heating or domestic hot water demand.

[0052] Refrigerant liquefaction facilitates subsequent throttling and pressure reduction, maintaining cycle continuity. The high-pressure liquid refrigerant at the condenser outlet flows through the throttling valve, where its pressure is reduced to 0.5 MPa due to the throttling effect. The throttling effect occurs when the high-pressure refrigerant flows through the narrow valve orifice, utilizing the local resistance generated by the sudden reduction in the flow channel cross-section to achieve a pressure reduction and state change of the refrigerant. This results in a low-pressure refrigerant flowing into the evaporator inlet, completing the entire cycle. The throttling valve reduces the refrigerant pressure, maintaining a low-pressure evaporation environment within the evaporator, ensuring heat absorption from the circulating water and improving the heat exchange efficiency within the evaporator.

[0053] Please see Figure 1 and Figure 5 The present invention provides an embodiment of a decentralized exhaust source heat pump centralized heat recovery system based on water-to-air heat exchange. The heat carrier outlet is connected to the input end of a regional heating station through an energy supply pipeline. The regional heating station is equipped with a reversing valve group to control the flow of the heat carrier to the energy-consuming equipment and the domestic hot water storage tank. The output end of the regional heating station is connected to the energy-consuming equipment and the domestic hot water storage tank through branch pipelines. The energy-consuming equipment is equipped with heat exchange components to exchange heat with the heat carrier. The heat exchange components in the domestic hot water storage tank are in contact with the heat carrier through the pipe wall. The return flow from the energy-consuming equipment and the domestic hot water storage tank is collected and connected to the heat carrier inlet of the condenser through a recovery pipe.

[0054] The reversing valve assembly includes a main reversing valve, branch control valves, and a signal receiving unit. The main reversing valve is installed on the main pipeline between the input and output ends of the heating station and is used to switch the main flow direction of the heat carrier. The branch control valves are connected to the branch pipelines of the energy-consuming equipment and the domestic hot water storage tank respectively and are used to control the on / off of each branch. The signal receiving unit is electrically connected to each valve, receives external control signals and drives the valves to operate, and is used for switching and distributing between different energy consumption paths.

[0055] Furthermore, the heat carrier that absorbs heat is heated to 60°C and enters the regional heating station through the power supply pipeline. The controller of the control module is connected to the temperature sensor of the energy-consuming equipment through the transmission line. The controller is also connected to the water temperature sensor of the domestic hot water storage tank through the transmission line. The control module drives the reversing valve group to switch and distribute by detecting the temperature signals of the energy-consuming equipment and the domestic hot water storage tank.

[0056] When the controller detects that the indoor temperature of the energy-consuming equipment is less than 25°C and the water temperature in the storage tank is less than 50°C, the controller sends a dual-path opening command to the signal receiving unit of the reversing valve group. The main reversing valve rotates to the dual-pass position, allowing the heat carrier to flow into the heating and hot water branch pipes simultaneously. Then, the signal receiving unit drives the two sets of branch control valves to open. The heat carrier flows through the heat exchange components of the energy-consuming equipment to release heat, raising the room temperature to 25°C. At the same time, it flows through the heat exchange tubes of the storage tank to heat the cold water, raising the water temperature to 50°C. The low-temperature carrier is collected and flows back through the recovery pipe.

[0057] When the controller detects that the indoor temperature of the energy-consuming equipment is less than 25℃, but the water temperature in the storage tank is greater than 50℃, the controller sends a heating single-circuit start command to the signal receiving unit. The main reversing valve switches to the heating position, the heating branch control valve opens, the hot water branch control valve closes, and all the heat carrier flows into the energy-consuming equipment. The heat is quickly released through the heat exchange components, raising the room temperature to above 25℃ within 20 minutes. The low-temperature carrier that releases heat flows back through the recovery pipe.

[0058] When the controller detects that the water temperature in the storage tank is less than 50℃, but the room temperature of the energy-consuming equipment is greater than 25℃, the controller sends a hot water single-channel start command to the signal receiving unit. The main reversing valve switches to the hot water on position, the hot water branch control valve opens, the heating branch control valve closes, and all the heat carrier flows into the heat exchange tube of the storage tank. The cold water is efficiently heated through the tube wall, and the water temperature is raised to 50℃ within 30 minutes. The low temperature carrier flows back through the recovery tube.

[0059] When the controller detects that the room temperature of the energy-consuming equipment is greater than 25°C and the water temperature in the storage tank is greater than 50°C, the controller sends a full-close signal to the electric air valves of all distributed exhaust hood branch ducts through the transmission line, driving the valve plates to rotate to the closed state, cutting off the channel for exhaust air from each functional area to enter the main duct. At the same time, the control module turns off the real-time detection function of the temperature sensor of the exhaust air acquisition module, retains the standby state, avoids invalid signal transmission, and stops collecting exhaust air. This can reduce the ineffective heat exchange between the heat exchanger and the circulating water, reduce the no-load energy consumption of the water pump and compressor, and at the same time avoid the problem of condensation in the pipeline caused by low-temperature exhaust air entering the system, thus extending the service life of the equipment.

[0060] Working principle: First, the distributed exhaust hoods of the exhaust collection module collect exhaust air from various functional areas of the building. The control module adjusts the electric air valves based on temperature sensor data, and high-temperature exhaust air is sent to the heat exchanger through the collection duct. In the water-to-air heat exchange module, the water pump drives the circulating water to flow in a closed loop between the heat exchanger and the heat pump evaporator. The circulating water absorbs the heat of the exhaust air through the heat exchanger wall, and the cooled exhaust air is discharged from the air side outlet.

[0061] Then, the circulating water in the evaporator of the heat pump unit transfers heat to the low-pressure refrigerant, causing it to evaporate into a gaseous state. After being compressed by the compressor, the refrigerant becomes a high-pressure, high-temperature gaseous refrigerant at 80°C, which enters the condenser to release heat. The heat carrier absorbs the heat and its temperature rises to 60°C.

[0062] Finally, the heat carrier enters the heat recovery and utilization module through the power supply pipeline. The control module distributes the heat carrier according to the room temperature of the energy-consuming equipment and the water temperature of the domestic hot water storage tank through the reversing valve group. After releasing heat, the carrier flows back to the condenser through the recovery pipe. Throughout the process, the control module dynamically adjusts the air valve, water pump, compressor and reversing valve group to achieve precise heat recovery and efficient utilization.

[0063] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A decentralized exhaust air source heat pump centralized heat recovery system based on water-gas heat exchange, comprising an exhaust air collection module, a water-gas heat exchange module, a heat pump unit and a heat recovery and utilization module, characterized in that: The exhaust gas acquisition module is connected to the water-to-air heat exchange module through a collection duct; The water-to-air heat exchange module includes a heat exchanger, a water pump, and a water circulation pipeline. The water-to-air heat exchange module is connected to the heat pump unit through a water circulation pipeline, and the heat pump unit is connected to the heat recovery module through a power supply pipe. The exhaust gas acquisition module includes a distributed exhaust hood, an air volume regulation component, and a collection duct. The distributed exhaust hoods are installed at the exhaust outlets of different functional areas of the building. Each branch duct of the distributed exhaust hood is equipped with an airflow regulating component. A filter screen is installed at the inlet of the distributed exhaust hood. The airflow regulating component includes a temperature sensor and an electric damper. The temperature sensor is used to detect the exhaust temperature, and the opening degree of the electric damper is adjusted according to the exhaust temperature. One end of the converging duct is connected to each distributed exhaust hood, and the other end of the converging duct is connected to the air-side inlet of the heat exchanger, which is used to centrally transport the dispersed exhaust air to the heat exchanger.

2. The heat recovery system of claim 1, wherein: The water circulation pipeline includes an outlet pipe and a return pipe; The heat exchanger is equipped with an air-side inlet, an air-side outlet, a water-side inlet, and a water-side outlet. The air-side inlet of the heat exchanger is connected to the main air duct, and the air-side outlet is used to discharge the heat-exchanged gas. The water-side inlet and outlet of the heat exchanger are connected to the water circulation pipeline. A water pump is installed in the water circulation pipeline. The water pump drives the circulating water to flow between the heat exchanger and the evaporator of the heat pump unit, so that the circulating water exchanges heat with the exhaust air on the air side in the heat exchanger. The air side and water side of the heat exchanger are isolated from each other, and the exhaust air and circulating water transfer heat through the heat exchanger.

3. The heat recovery system of claim 2, wherein: The heat pump unit includes a compressor, an evaporator, and a condenser; The compressor, evaporator, and condenser are connected in sequence through pipelines to form a closed loop. The evaporator is equipped with a water-side inlet, a water-side outlet, an inlet, and an outlet. The water-side inlet of the evaporator is connected to the outlet pipe of the water circulation pipeline, and the water-side outlet of the evaporator is connected to the return pipe of the water circulation pipeline to form a circulating water circuit. The evaporator outlet is connected to the compressor inlet to allow low-pressure, low-temperature refrigerant vapor to enter the compressor. The compressor outlet is connected to the condenser inlet to send high-pressure, high-temperature refrigerant vapor into the condenser. The condenser outlet is connected to the evaporator inlet to throttle and reduce the pressure of the condensed refrigerant liquid before it is fed into the evaporator to complete the circulation.

4. The heat recovery system of claim 3, wherein: The condenser is connected to the heat recovery module via a power supply pipe, and the heat recovery module is connected to the heat pump unit via a recovery pipe to form a circulation pipeline. The heat recovery and utilization module includes a district heating station, energy-consuming equipment, and a domestic hot water storage tank; The condenser has a heat carrier inlet and a heat carrier outlet. The heat carrier outlet is connected to the input end of the district heating station through a power supply pipeline. The district heating station is equipped with a reversing valve group to control the flow of heat carrier to the energy-consuming equipment and the domestic hot water storage tank. The output end of the district heating station is connected to the energy-consuming equipment and the domestic hot water storage tank through branch pipelines. The energy-consuming equipment has heat exchange components inside to exchange heat with the heat carrier. The heat exchange components in the domestic hot water storage tank are in contact with the heat carrier through the pipe wall. The return flow from the energy-consuming equipment and the domestic hot water storage tank is collected and connected to the heat carrier inlet of the condenser through a recovery pipe.

5. The heat recovery system of claim 3, wherein: The circulating water in the evaporator forms an independent circulation system. The circulating water is sent to the water-side inlet of the evaporator through the outlet pipe of the water-to-air heat exchange module. After the circulating water completes heat exchange with the refrigerant in the evaporator, it is driven by a water pump to flow from the water-side outlet of the evaporator back to the heat exchanger of the water-to-air heat exchange module through the return water pipe. The heat carrier in the condenser forms another independent circulation system. The heat carrier enters the regional heating station of the heat recovery and utilization module through the energy supply pipeline from the heat carrier outlet of the condenser. After being distributed by the reversing valve group, it flows into the energy-consuming equipment and the domestic hot water storage tank. After releasing heat, the heat carrier is collected and returned to the heat carrier inlet of the condenser through the recovery pipe. The circulating water system of the evaporator is connected to the water-to-air heat exchange module and circulates only between the two. The heat carrier circulation system of the condenser is connected to the heat recovery and utilization module and circulates only between the two. The two circulation systems are independent of each other.

6. A decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange according to claim 1, characterized in that: The distributed exhaust hood is funnel-shaped and has an inlet and an outlet. The inlet has a removable filter to intercept particulate matter in the exhaust air. The outlet of the distributed exhaust hood is connected to the main exhaust hood via branch ducts. A temperature sensor is installed in the branch duct at the outlet of the distributed exhaust hood to detect the temperature of the exhaust air flowing through it. An electric damper is installed in the branch duct to adjust the valve opening. All branch ducts are connected to the inlet of the main exhaust hood, and the outlet of the main exhaust hood is connected to the air-side inlet of the heat exchanger in the water-to-air heat exchange module.

7. A decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange according to claim 4, characterized in that: The reversing valve assembly includes a main reversing valve, a branch control valve, and a signal receiving unit; The main reversing valve is installed on the main pipeline between the input and output ends of the heating station to switch the main direction of the heat carrier. The branch control valves are connected to the branch pipelines of the energy-consuming equipment and the domestic hot water storage tank to control the opening and closing of each branch. The signal receiving unit is electrically connected to each valve to receive external control signals and drive the valves to operate, which is used for switching and distributing between different energy consumption paths.

8. A decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange according to claim 1, characterized in that: One end of the outlet pipe of the water circulation pipeline is connected to the water-side outlet of the heat exchanger in the water-to-air heat exchange module, and the other end is connected to the water-side inlet of the evaporator of the heat pump unit through a flange. One end of the return pipe of the water circulation pipeline is connected to the water-side outlet of the evaporator, and the other end is connected to the water-side inlet of the heat exchanger.

9. A decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange according to claim 1, characterized in that: The temperature sensor is connected to the control module via a transmission line; The control module includes a controller and transmission lines; The controller is connected to the temperature sensors and electric air valves in each branch duct of the distributed exhaust hood via transmission lines. After receiving the temperature signal, the controller outputs control commands to the electric air valves to adjust the valve opening. The controller is also connected to the signal receiving unit via transmission lines to transmit reversing and flow control signals to the signal receiving unit.

10. A decentralized exhaust heat pump centralized heat recovery system based on water-to-air heat exchange according to claim 9, characterized in that: The controller is connected to the water pump via a transmission line, which is connected to the drive motor in the water pump. The controller outputs start, stop, and speed control signals to the drive motor. The controller is also connected to the compressor via a transmission line, which is connected to the frequency converter in the compressor. The controller adjusts the operating frequency of the compressor through the frequency converter.

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