Heat pump system for a beer production line and method for controlling the same

Abstract

The application provides a heat pump system for a beer production line, comprising: a heat recovery layer, a heat recovery layer water inlet, a heat source side water inlet of a first water source heat pump unit, a heat source side water outlet of the first water source heat pump unit and a heat recovery water outlet which are sequentially fluidly connected and form an ice water path for ice water flow, and a first regulating valve is arranged on the ice water path; a heat utilization layer, a heat utilization layer water inlet, a cold source side water inlet of a second water source heat pump unit, a cold source side water outlet of the second water source heat pump unit and a heat utilization layer water outlet which are sequentially fluidly connected and form a hot water path for hot water flow, and a second regulating valve is arranged on the hot water path; an intermediate layer, a cold source side water inlet of the first water source heat pump, a cold source side water outlet of the first water source heat pump, a heat source side water inlet of the second water source heat pump and a heat source side water outlet of the second water source heat pump which are sequentially fluidly connected and form an intermediate loop, and a buffer water tank and an intermediate water pump are arranged on the intermediate loop.

Description

Technical Field

[0001] This invention relates to the field of heat pump system technology, and in particular to a heat pump system for a beer production line and its control method. Background Technology

[0002] Beer production lines have hot water systems for providing high-temperature hot water and chilled water systems for providing low-temperature chilled water. High-temperature hot water is mainly used for bottle washing and sterilization, with a maximum temperature requirement of 92°C. Low-temperature chilled water is mainly used for wort cooling, fermentation tank temperature control, beer maturation and storage, and bottling line cooling, with a lower temperature requirement of 4-12°C.

[0003] Traditional beer production lines typically use cooling towers to provide cooling for the ice water system. During this process, some of the heat from the ice water is directly released into the atmosphere without being utilized. This reduces the thermal energy utilization rate of the beer production line to some extent. Summary of the Invention

[0004] In order to solve the technical problem of low thermal energy utilization rate in traditional beer production lines, the purpose of this invention is to provide a heat pump system and its control method for beer production lines, which can effectively recover and utilize the waste heat of ice water.

[0005] To achieve the above objectives, the present invention provides the following first technical solution: a heat pump system for a beer production line, the beer production line including an ice water system and a hot water system, both the ice water system and the hot water system having an outlet and a return outlet; the heat pump system comprising: a heat recovery layer, including a heat recovery layer inlet fluidly connected to the outlet of the ice water system, a heat recovery layer outlet fluidly connected to the return outlet of the ice water system, a first water source heat pump unit, and a first regulating valve with adjustable opening; the heat recovery layer inlet, the heat source side inlet of the first water source heat pump unit, the heat source side outlet of the first water source heat pump unit, and the heat recovery layer outlet are sequentially fluidly connected to form an ice water path for ice water flow; the first regulating valve is disposed on the ice water path to adjust the ice water flow rate; and a heat utilization layer, including a heat utilization layer inlet fluidly connected to the outlet of the hot water system, a heat utilization layer outlet fluidly connected to the return outlet of the hot water system, a second water source heat pump unit, and a first regulating valve with adjustable opening. The second regulating valve is configured to regulate the flow rate of hot water. The heat utilization layer inlet, the cold source side inlet of the second water source heat pump unit, the cold source side outlet of the second water source heat pump unit, and the heat utilization layer outlet are sequentially fluidly connected to form a hot water path. The intermediate layer includes a buffer tank for storing heat transfer water and an intermediate water pump for transporting heat transfer water. The cold source side inlet of the first water source heat pump unit, the cold source side outlet of the first water source heat pump unit, the heat source side inlet of the second water source heat pump unit, and the heat source side outlet of the second water source heat pump unit are sequentially fluidly connected to form an intermediate loop for circulating heat transfer water. The buffer tank and the intermediate water pump are both configured on the intermediate loop. A controller is also included, which is simultaneously signal-connected to the first water source heat pump unit, the second water source heat pump unit, the first regulating valve, the second regulating valve, and the intermediate water pump to control the operation of the heat pump system.

[0006] In the first technical solution described above, preferably, the heat utilization layer further includes an air source heat pump unit and a third regulating valve with adjustable opening. The heat utilization layer inlet, the cold source side inlet of the air source heat pump unit, the cold source side outlet of the air source heat pump unit, and the heat utilization layer outlet are sequentially fluidly connected. The third regulating valve is disposed at the cold source side inlet or cold source side outlet of the air source heat pump unit and is signal-connected to the controller.

[0007] In the above preferred embodiment, more preferably, the heat utilization layer further includes a third water source heat pump unit and a fourth regulating valve with adjustable opening. The inlet of the heat utilization layer, the cold source side inlet of the air source heat pump unit, the cold source side outlet of the air source heat pump unit, the cold source side inlet of the second water source heat pump unit, the cold source side outlet of the second water source heat pump unit, the cold source side inlet of the third water source heat pump unit, the cold source side outlet of the third water source heat pump unit, and the outlet of the heat utilization layer are sequentially fluidly connected. The cold source side outlet of the second water source heat pump unit is fluidly connected to the inlet of the air source heat pump unit. The fourth regulating valve is disposed at the cold source side inlet or cold source side outlet of the third water source heat pump unit and is signal-connected to the controller. Further preferably, the heat utilization layer also includes a three-way valve connected to the controller via a signal. The three-way valve has an inlet, a first outlet with an independently adjustable opening, and a second outlet with an independently adjustable opening. The inlet is fluidly connected to the cold source side outlet of the second water source heat pump unit, the first outlet is fluidly connected to the cold source side inlet of the third water source heat pump unit, and the second outlet is fluidly connected to the cold source side inlet of the air source heat pump unit. The controller can control the opening of the first outlet and the second outlet based on the water temperature of the cold source side outlet of the third water source heat pump unit.

[0008] In the above preferred embodiment, it is further preferred that the heat utilization layer inlet is simultaneously fluidly connected to the cold source side inlet of the air source heat pump unit and the cold source side inlet of the second water source heat pump unit, and the heat utilization layer outlet is simultaneously fluidly connected to the cold source side outlet of the air source unit and the cold source side outlet of the second water source heat pump unit.

[0009] In the first technical solution described above, preferably, the heat recovery layer further includes a fourth water source heat pump unit, wherein the heat recovery layer inlet, the heat source side inlet of the first water source heat pump unit, the heat source side outlet of the first water source heat pump unit, the heat source side inlet of the fourth water source heat pump unit, the heat source side outlet of the fourth water source heat pump unit, and the heat recovery layer outlet are sequentially fluidly connected; the cold source side inlet of the first water source heat pump unit is fluidly connected to the cold source side inlet of the fourth water source heat pump unit, and the cold source side outlet of the first water source heat pump unit is fluidly connected to the cold source side outlet of the fourth water source heat pump unit.

[0010] In the first technical solution described above, preferably, it also includes a remote communication template for signal connection to the controller, so as to upload the real-time data of the heat pump system to the cloud platform.

[0011] Furthermore, the present invention also provides a control method for a heat pump system applied to any of the above-mentioned first technical solution and its preferred solutions. The first water source heat pump unit includes a variable frequency compressor, which has an upper frequency limit and a lower frequency limit. The control method includes: S1, obtaining the current evaporation temperature T1 of the heat transfer medium of the first water source heat pump; S2, setting the frequency of the compressor based on the evaporation temperature T1; wherein, when T1≤25℃, the compressor frequency of the first water source heat pump is set to the lower frequency limit D; when T1≥55℃, the compressor frequency of the first water source heat pump is set to the upper frequency limit U; when 25℃<T1<55℃, the compressor frequency of the first water source heat pump is set to: (T1-25)*(UD) / 25+D; S3, obtaining the current flow rate of chilled water or the water temperature at the outlet of the heat recovery layer, and adjusting the opening of the first regulating valve.

[0012] In the second technical solution described above, preferably, the control method further includes the following steps between steps S2 and S3: obtaining the water temperature T2 at the cold source side outlet of the first water source heat pump, and adjusting the frequency of the compressor based on the water temperature T2; when T2≤70℃, increasing the set compressor frequency by 2; when 70℃<T2≤80℃, increasing the set compressor frequency by 1; when T2>80℃, maintaining the currently set compressor frequency.

[0013] Compared to existing technologies, the heat pump system provided by the first technical solution of this invention can cool the chilled water and recover its waste heat through a first water source heat pump located in the heat recovery layer, and finally transfer the recovered heat to the hot water through a second water source heat pump in the heat utilization layer, thereby improving the thermal energy utilization rate of the beer production line. The intermediate layer can temporarily store the heat recovered from the chilled water to coordinate the heat supply and heat load of the heat pump system. Attached Figure Description

[0014] Figure 1 This is a system diagram of the heat pump system provided by the present invention; Figure 2 for Figure 1 The diagram shows the controller signal connection of the heat pump system. Figure 3 A flowchart of the control method provided by the present invention.

[0015] The image is labeled as follows: 100. Heat pump system; 11. Heat recovery layer inlet; 12. Heat recovery layer outlet; 13. First water source heat pump unit; 14. Second water source heat pump unit; 15. First regulating valve; 21. Buffer water tank; 22. Intermediate water pump; 31. Inlet of heat utilization layer; 32. Outlet of heat utilization layer; 33. Third water source heat pump unit; 34. Fourth water source heat pump unit; 35. Second regulating valve; 36. Third regulating valve; 37. High temperature water pump; 38. Air source heat pump unit; 39. Fourth regulating valve; 310. Three-way valve; 4. Controller; 41. First calorimeter; 42. Second calorimeter; 43. Third calorimeter; 44. Remote communication module; Detailed Implementation

[0016] To explain in detail the technical content, structural features, achieved objectives and effects of this application, the technical solutions in the embodiments of this application will be described below with reference to the accompanying drawings.

[0017] In this application, spatial relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side” (e.g., as in a “sidewall”) are used to describe the relationship between one element and another element as shown in the accompanying drawings. Spatial relative terms are intended to include different orientations of the device in use, operation, and / or manufacture other than those depicted in the drawings. For example, if the device in the drawings is flipped, an element described as “below” or “under” another element or feature would then be positioned “above” said other element or feature. Thus, the exemplary term “below” can include both above and below orientations. Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), thus interpreting the spatial relative descriptive terms used herein accordingly.

[0018] This invention provides a heat pump system for a beer production line, designed to recover heat from the ice water in the beer production line and transfer some of that heat to the hot water, thereby improving the energy efficiency of the beer production line. For clarity, the necessary background technology and terminology are explained below.

[0019] A heat pump is a highly efficient heat transfer device, primarily used for building heating, cooling, or hot water supply. Its core principle is to transfer a portion of the heat from a heat source fluid (such as air or water) to a cold source fluid (usually water) by consuming a small amount of electrical energy. In this application, the term "heat source fluid" refers to the fluid that provides heat to the heat transfer medium within the corresponding heat pump, and "cold source fluid" refers to the fluid that absorbs heat from the heat transfer medium within the corresponding heat pump. Understandably, in the same heat pump system, the cold source fluid of one heat pump may be the heat source fluid of another heat pump (such as the heat transfer water in this application). In this application, a heat pump using water as the heat source fluid is called a water source heat pump, and a heat pump using ambient air as the heat source fluid is called an air source heat pump.

[0020] A heat pump operates based on the reverse Carnot cycle principle. Its main components include a compressor, condenser, expansion valve, and evaporator. These components are sequentially fluidly connected, forming a loop for the circulation of the heat transfer medium. In this cycle, the gaseous heat transfer medium exiting the evaporator is compressed in the compressor, causing a significant increase in temperature and pressure. The high-temperature, high-pressure gaseous heat transfer medium enters the condenser, releasing heat and condensing into a liquid state. This heat is transferred to the cold source fluid, causing its temperature to rise. The liquid heat transfer medium then passes through the expansion valve, causing its pressure to decrease. The liquid heat transfer medium exiting the expansion valve enters the evaporator, absorbing some heat from the heat source fluid and evaporating into a gaseous state, causing the heat source fluid's temperature to decrease. Thus, the heat transfer medium transfers a portion of the heat from the heat source fluid to the cold source fluid.

[0021] In this application, "heat source side inlet" and "heat source side outlet" refer to the inlet and outlet of the heat source fluid flowing into and out of the heat pump, respectively. It can be understood that the heat source side inlet, evaporator, and heat source side outlet are sequentially fluidly connected. "cold source side inlet" and "cold source side outlet" refer to the inlet and outlet of the cold source fluid flowing into and out of the heat pump, respectively. It can be understood that the cold source side inlet, condenser, and cold source side outlet are sequentially fluidly connected.

[0022] In this application, "heat pump unit" refers to a unit composed of several heat pumps. When the heat pump unit includes two or more heat pumps, the heat pumps within the unit can be connected in series or in parallel. Generally, a series connection can provide a higher temperature rise (or temperature drop) but a smaller fluid flow rate; a parallel connection can provide a higher fluid flow rate but a lower temperature rise (or temperature drop). The aforementioned series and parallel connection configurations and their advantages and disadvantages are common knowledge to those skilled in the art. Therefore, the following embodiments will all present the technical solution in the form of a heat pump unit. Those skilled in the art can select a single, series, or parallel heat pump at each heat pump unit based on the actual application situation.

[0023] For heat pump units in series, the heat source and cold source inlets of the heat pump unit are the heat source and cold source inlets of the upstream heat pump on the corresponding side, and the heat source and cold source outlets of the heat pump unit are the heat source and cold source outlets of the downstream heat pump on the corresponding side. For heat pump units in parallel, the heat source and cold source inlets and outlets of the heat pump unit are the heat source and cold source inlets and outlets of each heat pump.

[0024] See Figure 1-2The illustration shows a heat pump system 100 for a beer production line provided in this application. The beer production line has an ice water system (not shown) for providing low-temperature ice water and a hot water system (not shown) for providing high-temperature hot water, both with inlets and outlets. The heat pump system 100 includes a heat recovery layer for recovering heat from the ice water, an intermediate layer for temporarily storing the recovered heat, a heat utilization layer for transferring the recovered heat to the hot water, and a controller 4 as the control center. The controller 4 is typically configured as a PLC (Programmable Logic Controller). In this application, "ice water," "hot water," and "heat transfer water" refer to the low-temperature ice water in the ice water system, the high-temperature hot water in the hot water system, and the intermediate water medium used to transfer heat, respectively.

[0025] The heat recovery layer includes a heat recovery layer inlet 11, which is fluidly connected to the outlet of the chilled water system; a heat recovery layer outlet 12, which is fluidly connected to the return outlet of the chilled water system; a first water source heat pump unit 13; a second water source heat pump unit 14; and a first regulating valve 15 with adjustable opening. The heat recovery layer inlet 11, the heat source side inlet of the first water source heat pump unit 13, the heat source side outlet of the first water source heat pump unit 13, the heat source side inlet of the second water source heat pump unit 14, the heat source side outlet of the second water source heat pump unit 14, and the heat recovery layer outlet 12 are sequentially fluidly connected to form a chilled water path for chilled water flow. The first regulating valve 15 is disposed on the chilled water path to adjust the flow rate of the chilled water. The controller 4 is signal-connected to the first regulating valve 15 and can control the opening degree of the first regulating valve 15.

[0026] In this design, the cold source side inlet of the first water source heat pump unit 13 is fluidly connected to the cold source side inlet of the second water source heat pump unit 14, and the cold source side outlet of the first water source heat pump unit 13 is fluidly connected to the cold source side outlet of the second water source heat pump unit 15. That is, the first and second water source heat pumps are connected in series on the heat source side and in parallel on the cold source side. Beer production lines require high temperature accuracy for both ice water and hot water. This design allows the ice water to achieve a sufficient temperature drop in the heat recovery layer to ensure the water temperature at the return outlet of the ice water system. Simultaneously, it also keeps the cold source side water temperature of the first and second heat pump units low, maintaining high heat transfer efficiency.

[0027] In other embodiments, if sufficient temperature drop can be achieved in the heat recovery layer, only one water source heat pump unit may be configured.

[0028] Continue reading Figure 1-2The heat utilization layer is equipped with a heat utilization layer inlet 31 (fluidly connected to the outlet of the hot water system), a heat utilization layer outlet 32 ​​(fluidly connected to the return outlet of the hot water system), a third water source heat pump unit 33, a fourth water source heat pump unit 34, an adjustable second regulating valve 35, an adjustable third regulating valve 36, and a high-temperature water pump 37 for transporting hot water. The high-temperature water pump 37 is located adjacent to the heat utilization layer inlet 31, where the temperature is lower, effectively reducing the required net positive suction head (NPSH) for the high-temperature water pump 37. The cold source side inlets of the third and fourth water source heat pump units are fluidly connected to the heat utilization layer inlet 31, and the cold source side outlets of the third and fourth water source heat pump units are fluidly connected to the heat utilization layer outlet 32. The second and third regulating valves are respectively located at the cold source side outlets (or cold source side inlets) of the third and fourth water source heat pump units to control the flow rate of hot water entering the third and fourth water source heat pump units. The controller 4 is simultaneously connected to the second and third regulating valves and can control the opening degree of the second and third regulating valves.

[0029] Furthermore, the heat utilization layer is also equipped with an air source heat pump unit 38 and a fourth regulating valve 39 located at the cold source side inlet or outlet of the air source heat pump unit 38. The heat utilization layer inlet 31, the cold source side inlet of the air source heat pump unit 38, the cold source side outlet of the air source heat pump unit 38, the cold source side inlet of the third water source heat pump unit 33, the cold source side outlet of the third water source heat pump unit 33, the cold source side inlet of the fourth water source heat pump unit 34, the cold source side outlet of the fourth water source heat pump unit 34, and the heat utilization layer outlet 32 ​​are sequentially fluidly connected. Typically, all equipment in the heat pump system 100 is arranged within the same building. The aforementioned air source heat pump unit 38 can absorb some of the heat from the ambient air, thereby reducing the building temperature. While improving heat utilization efficiency, it can also reduce the temperature difference between the chilled water and the building temperature, reducing chilled water cold leakage. The controller 4 is connected to the fourth regulating valve 39 and can control the opening degree of the fourth regulating valve 39.

[0030] Furthermore, the cold source side outlet of the third water source heat pump unit 33 is fluidly connected to the cold source side inlet of the air source heat pump unit 38. Thus, a loop for hot water circulation is formed between the air source heat pump unit 38 and the third water source heat pump unit 33. The controller 4, by adjusting the output of the high-temperature water pump 37 and the opening of the second, third, and fourth regulating valves, can regulate the flow rate of the hot water flowing from the cold source side outlet of the third water source heat pump 33 into the aforementioned recirculation system and the fourth water source heat pump unit 34. This design allows hot water to circulate within the loop and increase the water temperature in the loop. A portion of the hot water in the loop is subsequently further heated in the fourth water source heat pump unit 34 to ensure that the water temperature at the heat utilization layer outlet 32 ​​meets the requirements of the beer production line and improves the heat pump system 100's precise temperature control capability at that location.

[0031] Furthermore, the heat utilization layer is also equipped with a three-way valve 310. This three-way valve 310 has an inlet (not shown in the figure) that is fluidly connected to the cold source side outlet of the third water source heat pump unit 33, a first outlet (not shown in the figure) that is fluidly connected to the cold source side inlet of the air source heat pump unit 38, and a second outlet (not shown in the figure) that is fluidly connected to the cold source side inlet of the fourth water source heat pump unit 34. The first and second outlets of the three-way valve 310 are both configured to have independently adjustable openings. The controller 4 is signal-connected to the three-way valve 310 and can control the opening of the first and second outlets to precisely control the water temperature at the heat utilization layer outlet 32.

[0032] In other embodiments, if the temperature rise requirement of hot water can be met, only one water source heat pump unit can be installed; alternatively, one water source heat pump unit and one air source heat pump unit can be installed, with the inlet of the heat utilization layer simultaneously connected to the cold source side inlet of the water source heat pump unit and the cold source side inlet of the air source heat pump unit, and the outlet of the heat utilization layer simultaneously connected to the cold source side outlet of the water source heat pump unit and the air source side outlet, that is, the water source heat pump unit and the air source heat pump unit are connected in parallel on the cold source side.

[0033] The heat source-side inlets and outlets of the third and fourth water source heat pump units in the heat utilization layer are fluidly connected to each other, meaning that the third and fourth water source heat pump units in the heat utilization layer are connected in parallel on the heat source side. The cold source-side inlets of each water source heat pump unit in the heat recovery layer, the cold source-side outlets of each water source heat pump unit in the heat recovery layer, the heat source-side inlets of each water source heat pump unit in the heat utilization layer, and the heat source outlets of each water source heat pump unit in the heat utilization layer are sequentially fluidly connected, forming an intermediate loop for the circulation of heat transfer water.

[0034] The intermediate layer includes a buffer tank 21 for temporary storage of heat transfer water and an intermediate water pump 22 for transporting heat transfer water. Both the buffer tank 21 and the intermediate water pump 22 are configured on the aforementioned intermediate loop. The buffer tank 22 coordinates the supply and demand relationship between the heat supply (i.e., the heat absorbed from the chilled water) and the heat load (i.e., the heat required for hot water) in the heat pump system 100. The intermediate water pump 22 is located between the heat source side outlet of the third and fourth water source heat pump units and the cold source side inlet of the first and second water source heat pump units. The water temperature at this location is relatively low, effectively reducing the net positive suction head (NPSH) required by the intermediate water pump 22.

[0035] Continue reading Figure 1-2The heat pump system 100 also includes a first calorimeter 41 disposed in the heat recovery layer, a second calorimeter 42 disposed in the intermediate layer, and a third calorimeter 43 disposed in the heat utilization layer. The first calorimeter 41 is used to obtain the total heat lost by the chilled water in the heat recovery layer, the second calorimeter 42 is used to obtain the total heat gained by the heat transfer water in the intermediate layer, and the third calorimeter 43 is used to obtain the total heat gained by the hot water in the heat utilization layer. The structure and working principle of the calorimeters are existing technologies and will not be described in detail here.

[0036] Furthermore, the heat pump system 100 also includes a remote communication module 44 for signal connection controller 4, so as to transmit the real-time data of the heat pump system 100 to the cloud platform for users to view on remote devices such as computers and mobile phones.

[0037] Combination Figure 3 To ensure the stability of the chilled water flow rate, this invention also provides a control method for controlling the chilled water temperature and flow rate. The following description uses a first heat pump unit 13 as an example. The first heat pump unit 13 has a variable frequency screw compressor (not shown in the figure), and a controller 4 is connected to the screw compressor and can adjust its frequency. The screw compressor has a lower frequency limit D (e.g., 25) and an upper frequency limit U (e.g., 50).

[0038] The control method provided by this invention includes the following steps: S1. Obtain the current evaporation temperature T1 of the heat transfer medium in the first water source heat pump unit; The evaporation temperature of the heat transfer medium is the phase change temperature at which the heat transfer medium evaporates within the corresponding evaporator. A higher evaporation temperature means a higher evaporation pressure, increased heat absorption (latent heat) by the heat transfer medium in the evaporator, and increased heat transfer per unit time (heating capacity). However, a higher evaporation temperature also means a higher suction pressure for the screw compressor, requiring a greater output.

[0039] S2. Based on the above evaporation temperature, set the frequency of the screw compressor; wherein, when T1≤25℃, the frequency of the screw is set to the lower frequency limit D; when T1≥55℃, the frequency of the screw compressor is set to the upper frequency limit U; when 25℃<T1<55℃, the frequency of the screw compressor is set to: (T1-25)*(UD) / 25+D; As mentioned above, the higher the evaporation temperature, the higher the output of the screw compressor, meaning the set frequency should be higher. However, the frequency of the screw compressor is also limited by its own upper and lower frequency limits. Therefore, a suitable screw compressor frequency can be obtained based on the evaporation temperature.

[0040] S3. Obtain the current flow rate of chilled water or the water temperature at the outlet of the heat recovery layer, and adjust the opening of the first regulating valve.

[0041] As mentioned above, the higher the evaporation temperature, the greater the heat transferred per unit time. Therefore, the flow rate of chilled water can be adjusted based on the frequency of the screw compressor. The adjustment method can be to preset a function between the screw compressor frequency and the chilled water flow rate. After obtaining the current chilled water flow rate (which can be obtained through sensors, etc.), the controller 4 adjusts the opening of the first regulating valve based on the difference between the current flow rate and the preset flow rate. Alternatively, it can obtain the water temperature at the outlet of the heat recovery layer and then adjust the opening of the first regulating valve.

[0042] As described above, the heat pump system 100 can periodically operate using the control method described above. The heat supply (i.e., the heat absorbed from the chilled water) of the heat pump system 100 is determined by first determining the frequency of the screw compressor; then, the chilled water temperature at the heat recovery layer outlet 12 is determined by adjusting the chilled water flow rate. This method effectively avoids fluctuations in the control system caused by simultaneous changes in chilled water flow rate and temperature, and improves the stability of the chilled water temperature.

[0043] Furthermore, considering that the water temperature at the cold source side outlet of the first and second water source heat pumps is low, it indicates that the heat demand of the heat pump system 100 is large (i.e., the hot water absorbs more heat, causing a drop in the temperature of the heat transfer water). Therefore, it is necessary to appropriately increase the heat supply of the heat pump system 100. Therefore, the above control method also includes step S21, located between steps S2 and S3: obtaining the current water temperature T2 at the cold source side outlet of the first water source heat pump unit, and adjusting the set frequency of the screw compressor based on the water temperature T2; wherein, when T2 ≤ 70℃, the set frequency of the screw compressor is increased by 2; when 70℃ < T2 ≤ 80℃, the set frequency of the screw compressor is increased by 1; when T2 > 80℃, the currently set frequency of the screw compressor is maintained.

[0044] The above embodiments are only for illustrating the technical concept and features of this application, and are intended to enable those skilled in the art to understand the content of this application and implement it accordingly. They should not be construed as limiting the scope of protection of this application. All equivalent changes or modifications made in accordance with the spirit of this application should be included within the scope of protection of this application.

Claims

1. A heat pump system for a beer production line, the beer production line comprising an ice water system and a hot water system, both the ice water system and the hot water system having an outlet and an inlet, characterized in that, The heat pump system includes: The heat recovery layer includes a heat recovery layer inlet fluidly connected to the outlet of the chilled water system, a heat recovery layer outlet fluidly connected to the return outlet of the chilled water system, a first water source heat pump unit, and a first regulating valve with adjustable opening. The heat recovery layer inlet, the heat source side inlet of the first water source heat pump unit, the heat source side outlet of the first water source heat pump unit, and the heat recovery layer outlet are sequentially fluidly connected to form a chilled water path for chilled water flow. The first regulating valve is disposed on the chilled water path to adjust the flow rate of the chilled water. The heat utilization layer includes a heat utilization layer inlet fluidly connected to the outlet of the hot water system, a heat utilization layer outlet fluidly connected to the return outlet of the hot water system, a second water source heat pump unit, and a second regulating valve with adjustable opening. The heat utilization layer inlet, the cold source side inlet of the second water source heat pump unit, the cold source side outlet of the second water source heat pump unit, and the heat utilization layer outlet are sequentially fluidly connected to form a hot water path for hot water flow. The second regulating valve is disposed on the hot water path to regulate the flow rate of hot water. The intermediate layer includes a buffer tank for storing heat transfer water and an intermediate water pump for transporting heat transfer water. The cold source side inlet of the first water source heat pump unit, the cold source side outlet of the first water source heat pump unit, the heat source side inlet of the second water source heat pump unit, and the heat source side outlet of the second water source heat pump unit are sequentially fluidly connected to form an intermediate loop for circulating heat transfer water. The buffer tank and the intermediate water pump are both disposed on the intermediate loop. The controller is simultaneously connected to the first water source heat pump unit, the second water source heat pump unit, the first regulating valve, the second regulating valve, and the intermediate water pump to control the operation of the heat pump system.

2. The heat pump system according to claim 1, characterized in that, The heat utilization layer also includes an air source heat pump unit and a third regulating valve with adjustable opening. The heat utilization layer inlet, the cold source side inlet of the air source heat pump unit, the cold source side outlet of the air source heat pump unit, and the heat utilization layer outlet are sequentially fluidly connected. The third regulating valve is located at the cold source side inlet or cold source side outlet of the air source heat pump unit and is signal-connected to the controller.

3. The heat pump system according to claim 2, characterized in that, The heat utilization layer further includes a third water source heat pump unit and a fourth regulating valve with adjustable opening. The inlet of the heat utilization layer, the cold source side inlet of the air source heat pump unit, the cold source side outlet of the air source heat pump unit, the cold source side inlet of the second water source heat pump unit, the cold source side outlet of the second water source heat pump unit, the cold source side inlet of the third water source heat pump unit, the cold source side outlet of the third water source heat pump unit, and the outlet of the heat utilization layer are sequentially fluidly connected. The cold source side outlet of the second water source heat pump unit is fluidly connected to the inlet of the air source heat pump unit. The fourth regulating valve is disposed at the cold source side inlet or cold source side outlet of the third water source heat pump unit and is signal-connected to the controller.

4. The heat pump system according to claim 3, characterized in that, The heat utilization layer also includes a three-way valve connected to the controller via a signal. The three-way valve has an inlet, a first outlet with an independently adjustable opening, and a second outlet with an independently adjustable opening. The inlet is fluidly connected to the cold source side outlet of the second water source heat pump unit, the first outlet is fluidly connected to the cold source side inlet of the third water source heat pump unit, and the second outlet is fluidly connected to the cold source side inlet of the air source heat pump unit. The controller can control the opening of the first outlet and the second outlet based on the water temperature of the cold source side outlet of the third water source heat pump unit.

5. The heat pump system according to claim 2, characterized in that, The heat utilization layer inlet is simultaneously fluidly connected to the cold source side inlet of the air source heat pump unit and the cold source side inlet of the second water source heat pump unit, and the heat utilization layer outlet is simultaneously fluidly connected to the cold source side outlet of the air source unit and the cold source side outlet of the second water source heat pump unit.

6. The heat pump system according to claim 1, characterized in that, The heat recovery layer further includes a fourth water source heat pump unit. The heat recovery layer inlet, the heat source side inlet of the first water source heat pump unit, the heat source side outlet of the first water source heat pump unit, the heat source side inlet of the fourth water source heat pump unit, the heat source side outlet of the fourth water source heat pump unit, and the heat recovery layer outlet are sequentially fluidly connected. The cold source side inlet of the first water source heat pump unit is fluidly connected to the cold source side inlet of the fourth water source heat pump unit, and the cold source side outlet of the first water source heat pump unit is fluidly connected to the cold source side outlet of the fourth water source heat pump unit.

7. The heat pump system according to claim 1, characterized in that, It also includes a remote communication template that connects to the controller to upload real-time data of the heat pump system to a cloud platform.

8. A control method for a heat pump system as described in any one of claims 1-7, characterized in that, The first water source heat pump unit includes a variable frequency screw compressor, which has an upper frequency limit and a lower frequency limit. The control method includes the following steps: S1. Obtain the current evaporation temperature T1 of the heat transfer medium in the first water source heat pump unit; S2. Based on the above evaporation temperature, set the frequency of the screw compressor; wherein, when T1≤25℃, the frequency of the screw is set to the lower frequency limit D; when T1≥55℃, the frequency of the screw compressor is set to the upper frequency limit U; when 25℃<T1<55℃, the frequency of the screw compressor is set to: (T1-25)*(UD) / 25+D; S3. Obtain the current flow rate of chilled water or the water temperature at the outlet of the heat recovery layer, and adjust the opening of the first regulating valve.

9. The control method according to claim 8, characterized in that, The method also includes the following steps between steps S2 and S3: obtaining the water temperature T2 at the cold source side outlet of the current first water source heat pump unit, and adjusting the set frequency of the screw compressor based on the water temperature T2; wherein, when T2≤70℃, the set frequency of the screw compressor is increased by 2; when 70℃<T2≤80℃, the set frequency of the screw compressor is increased by 1; when T2>80℃, the currently set frequency of the screw compressor is maintained.

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