A drain system for a two-stage cascade heat pump

Abstract

The utility model discloses a kind of drainage systems for two-stage cascade heat pump, including condensate water collection unit, for collecting the condensate water generated by two-stage heat pump's evaporator, intercooler and pre-cooler;Conveying pipeline, its input end is communicated with condensate water collection unit;Electric water valve, is set on conveying pipeline, for controlling the on-off of condensate water's delivery;Heat recovery unit, with the output end of conveying pipeline communication, for carrying out heat recovery to condensate water;Condensing pump unit, through pipeline with heat recovery unit communication, for discharging system to the condensate water that has been heat recovered;Control unit is electrically connected with electric water valve, temperature sensor on pipeline respectively, for controlling the action of electric water valve according to the detection signal of temperature sensor, product advantage: system is through plate heat recovery device to the condensate water generated by evaporator, intercooler and pre-cooler carries out waste heat recovery, avoid the waste of heat caused by high-temperature condensate water direct discharge.

Description

Technical Field

[0001] This utility model relates to the field of two-stage heat pump technology, and in particular to a drainage system for a two-stage cascade heat pump. Background Technology

[0002] Two-stage regenerative heat pumps are widely used in heating, cooling, and hot water supply due to their high energy efficiency and wide applicable temperature range. During operation, core heat exchange components such as the evaporator, intercooler, and precooler generate a large amount of condensate due to temperature differences. If the condensate is not treated in time, it can easily accumulate inside the equipment, leading to component corrosion, reduced heat exchange efficiency, and even equipment failure. Furthermore, the condensate contains heat, and direct discharge results in energy waste. In addition, the condensate may contain dust and impurities, which can clog pipes over time, increasing maintenance costs. In existing technologies, the drainage systems of two-stage regenerative heat pumps mostly adopt simple direct pipe discharge or manual control methods, which have the following defects: incomplete condensate collection, easily missing condensate generated by some components; lack of effective impurity filtration structure, resulting in a high risk of pipe blockage; failure to recover heat from condensate, resulting in low energy utilization; and drainage control relying on manual or simple mechanical valves, which cannot be dynamically adjusted according to operating conditions, resulting in poor flexibility. Utility Model Content

[0003] The purpose of this invention is to overcome the defects of existing two-stage regenerative heat pump drainage systems, such as incomplete collection, insufficient impurity filtration, heat waste, and unintelligent control, and to provide a drainage system for two-stage regenerative heat pumps.

[0004] This utility model achieves the above objectives through the following technical solutions: A drainage system for a two-stage cascade heat pump includes a condensate collection unit for collecting condensate from the evaporator, intercooler, and precooler of the two-stage cascade heat pump; a delivery pipeline with its inlet connected to the condensate collection unit; an electric water valve installed on the delivery pipeline for controlling the flow of condensate; a heat recovery unit connected to the output of the delivery pipeline for heat recovery of the condensate; a condensate pump unit connected to the heat recovery unit via a pipeline for discharging the heat-recovered condensate from the system; and a control unit electrically connected to the electric water valve and a temperature sensor on the pipeline for controlling the operation of the electric water valve based on the detection signal from the temperature sensor.

[0005] Furthermore, the condensate collection unit includes a collection tank with multiple grid structures inside for preliminary filtration of impurities in the condensate. To prevent impurities in the condensate from clogging the pipes or affecting the heat recovery efficiency, the condensate collection unit includes a collection tank with multiple grid structures inside. The aperture of the grids can be designed according to the actual particle size of the impurities. Preliminary filtration of the condensate is achieved through physical interception, and the intercepted impurities can be cleaned periodically.

[0006] Furthermore, the heat recovery unit is a plate-type recovery device with multiple sets of heat exchange plates inside, used to realize heat exchange between condensate and the fluid to be treated. In order to improve the heat recovery efficiency, the heat recovery unit adopts a plate-type recovery device, which has multiple sets of parallel heat exchange plates inside. The condensate and the fluid to be heated / cooled (such as circulating water) flow on both sides of the plates respectively, and perform efficient heat exchange through the plates. The heat exchange efficiency can reach more than 80%, effectively recovering the waste heat in the condensate.

[0007] Furthermore, the conveying pipeline is also equipped with a discharge pipe for discharging condensate during maintenance or abnormal operating conditions. To facilitate system maintenance or respond to abnormal operating conditions (such as pipeline blockage or equipment repair), the conveying pipeline is also equipped with discharge fittings (such as manual ball valves or quick couplings) that can directly discharge condensate without starting the main drainage process, thereby improving the system's maintenance convenience.

[0008] Furthermore, the temperature sensor is installed on the pipeline between the heat recovery unit and the condensate pump to detect the temperature of the condensate after heat recovery. In order to accurately monitor the heat recovery effect and provide a signal to the control unit, the temperature sensor is installed on the pipeline between the heat recovery unit and the condensate pump unit to detect the temperature of the condensate after heat recovery in real time. The control unit can determine whether heat recovery is completed based on the temperature.

[0009] Furthermore, the control unit is also electrically connected to the condensate pump and is used to control the start and stop of the condensate pump.

[0010] Furthermore, the bottom of the collection tank is provided with a drain outlet for discharging deposited impurities.

[0011] Compared with the prior art, the beneficial effects of this utility model are: 1. The system recovers waste heat from the condensate produced by the evaporator, intercooler and precooler through a plate heat recovery device, transferring the heat in the condensate to the circulating water or other fluids to be heated / cooled. This design avoids the heat waste caused by the direct discharge of high-temperature condensate, and allows the waste heat to be reused. This reduces the additional energy consumption of the heat pump system and indirectly improves the heating / cooling efficiency of the entire heat pump system, meeting the application requirements of energy saving and consumption reduction.

[0012] 2. On the one hand, the grid structure of the condensate collection unit achieves preliminary filtration of impurities, preventing solid particles from clogging the delivery pipelines, heat exchange plates, or condensate pump, thus reducing equipment wear. On the other hand, the control unit monitors the condensate temperature after heat recovery in real time through temperature sensors, precisely controlling the on / off state of the electric water valve and the start / stop of the condensate pump to ensure that discharge is only completed after heat recovery, while preventing water accumulation or backflow under abnormal operating conditions. Furthermore, the design of the discharge pipes facilitates rapid pressure relief and drainage during maintenance, further reducing the risk of system failure and extending the service life of the heat pump unit and related drainage system components.

[0013] 3. The system's structural design fully considers operation and maintenance needs: impurities intercepted by the grille can be cleaned periodically without complex disassembly; the discharge fittings (manual ball valve / quick connector) support direct discharge of condensate during abnormal operating conditions or maintenance, without needing to start the main drainage process, shortening downtime for maintenance; intelligent control logic reduces the frequency of manual operation, and the control unit can automatically adjust the equipment's operating status based on detection signals, reducing manual monitoring and operation costs. The overall design achieves convenient management of the entire "filtration-recovery-discharge" process, improving the system's practicality and operation and maintenance efficiency. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the present invention.

[0015] In the diagram, 1-condensate collection unit, 2-heat recovery unit, 3-control unit, and 4-condensate pump unit. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] Combination Figure 1As shown, a drainage system for a two-stage cascade heat pump includes a condensate collection unit for collecting condensate from the evaporator, intercooler, and precooler of the two-stage cascade heat pump; a delivery pipeline with its inlet connected to the condensate collection unit; an electric water valve installed on the delivery pipeline for controlling the flow of condensate; a heat recovery unit connected to the outlet of the delivery pipeline for heat recovery of the condensate; a condensate pump unit connected to the heat recovery unit via a pipeline for discharging the heat-recovered condensate from the system; and a control unit electrically connected to the electric water valve and a temperature sensor on the pipeline for controlling the operation of the electric water valve based on the detection signal from the temperature sensor. The condensate collection unit uses a stainless steel collection tank. The input end of the collection tank is connected to the condensate outlets of the evaporator, intercooler, and precooler of the two-stage regenerative heat pump via branch pipes, ensuring that the condensate generated by each component can flow into the collection tank. Three layers of grids are horizontally installed inside the collection tank, with an adjacent grid spacing of 10cm, to intercept dust, debris, and other impurities in the condensate. A drain outlet with a manual valve is located on one side of the bottom of the collection tank, which is opened once a week to drain the deposited impurities. The heat recovery unit uses a plate heat exchanger, with its hot-side inlet connected to the output end of the delivery pipeline (through which condensate is introduced), and its cold-side inlet connected to the auxiliary circulating water pipeline of the heat pump (through which circulating water to be heated is introduced). Heat exchange is achieved through 20 sets of stainless steel heat exchange plates, and the waste heat of the condensate is absorbed by the circulating water and used for auxiliary heating of the heat pump.

[0018] The condensate collection unit includes a collection tank with multiple grid structures for preliminary filtration of impurities in the condensate. To prevent impurities from clogging pipes or affecting heat recovery efficiency, the condensate collection unit includes a collection tank with multiple grid structures. The grid aperture can be designed according to the actual impurity particle size (e.g., 5-10mm). Preliminary filtration of condensate is achieved through physical interception, and the intercepted impurities can be cleaned periodically. The heat recovery unit is a plate-type recovery device with multiple sets of heat exchange plates inside for heat exchange between the condensate and the fluid to be treated. To improve heat recovery efficiency, the heat recovery unit uses a plate-type recovery device with multiple sets of parallel heat exchange plates inside. The condensate and the fluid to be heated / cooled (such as circulating water) flow on opposite sides of the plates, achieving efficient heat exchange through the plates. The heat exchange efficiency can reach 80%. The system effectively recovers over 0% of the waste heat in the condensate. A drain valve is installed on the delivery pipeline for discharging condensate during maintenance or abnormal operating conditions. To facilitate system maintenance or respond to abnormal conditions (such as pipeline blockage or equipment repair), drain fittings (such as manual ball valves or quick couplings) are also installed on the delivery pipeline, allowing direct discharge of condensate without activating the main drainage process, thus improving system maintenance convenience. A temperature sensor is installed on the pipeline between the heat recovery unit and the condensate pump to detect the temperature of the condensate after heat recovery. To accurately monitor the heat recovery effect and provide a signal to the control unit, the temperature sensor is installed on the pipeline between the heat recovery unit and the condensate pump unit to detect the temperature of the condensate after heat recovery in real time. The control unit can determine whether heat recovery is complete based on this temperature. The control unit is also electrically connected to the condensate pump to control its start and stop.

[0019] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0020] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A drainage system for a two-stage cascade heat pump, characterized in that, The system includes a condensate collection unit for collecting condensate from the evaporator, intercooler, and precooler of a two-stage regenerative heat pump; a delivery pipeline with its inlet connected to the condensate collection unit; an electric water valve installed on the delivery pipeline for controlling the flow of condensate; a heat recovery unit connected to the output of the delivery pipeline for heat recovery of the condensate; a condensate pump unit connected to the heat recovery unit via a pipeline for discharging the heat-recovered condensate from the system; and a control unit electrically connected to the electric water valve and a temperature sensor on the pipeline for controlling the operation of the electric water valve based on the detection signal from the temperature sensor.

2. The drainage system for a two-stage cascade heat pump according to claim 1, characterized in that: The condensate collection unit includes a collection tank, which is equipped with multiple grid structures for preliminary filtration of impurities in the condensate.

3. A drainage system for a two-stage cascade heat pump according to claim 2, characterized in that: The heat recovery unit is a plate-type recovery device, which has multiple sets of heat exchange plates inside to realize the heat exchange between condensate and the fluid to be treated.

4. A drainage system for a two-stage cascade heat pump according to claim 3, characterized in that: The pipeline is also equipped with a drain pipe for draining condensate during maintenance or abnormal operating conditions.

5. A drainage system for a two-stage cascade heat pump according to claim 4, characterized in that: The temperature sensor is installed on the pipeline between the heat recovery unit and the condensate pump to detect the temperature of the condensate after heat recovery.

6. A drainage system for a two-stage cascade heat pump according to claim 5, characterized in that: The control unit is also electrically connected to the condensate pump and is used to control the start and stop of the condensate pump.

7. A drainage system for a two-stage cascade heat pump according to claim 6, characterized in that, The bottom of the collection tank is equipped with a drain outlet for discharging deposited impurities.

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