Heat pump drying system

Abstract

The utility model discloses a heat pump drying system which comprises a dehumidification reheating heat pump system, a heat pump system, a heat pump system and a heat pump system. The heat storage water tank is located below the first evaporator and used for storing condensate water generated by the first evaporator; the heat recovery heat pump system comprises a second compressor, a second condenser, a second throttling device and a second evaporator which are connected in sequence; the second evaporator is connected with the heat storage water tank and used for providing heat for the second condenser through water in the heat storage water tank. The second condenser communicates with the air inlet of the drying room and is used for conducting secondary heating on the inlet air entering the drying room. The problems that in the prior art, condensate water in a heat pump drying system is not effectively utilized, and heat is wasted are solved, dehumidification condensate water heat is fully utilized, the air supply temperature is increased, the whole machine energy saving performance of the heat pump drying system is improved, and the temperature regulation and control range of the drying process is widened.

Description

TECHNICAL FIELD

[0001] The utility model relates to drying technical field, specifically, relate to a kind of heat pump drying system. BACKGROUND

[0002] Heat pump drying system is applied in crop, fruit and vegetable, silt etc. in industry and agriculture, using high-temperature heat pump principle, the temperature in drying / roasting room is improved, and the moisture in drying object is removed. In the dehumidification process, the evaporator of heat pump will condense a large amount of condensate water, and the temperature of condensate water in heat pump drying system is relatively high, generally above 30℃-40℃ or even higher, and this part of heat directly discharged will cause a lot of heat waste.

[0003] Patent No. 202010924128.2 discloses a kind of heat pump drying system, but the system mainly relies on opening bypass air duct, part of the humid hot air in drying room is introduced into condenser, and the dehumidified air after cooling from evaporator is combined and reheated, then high-temperature hot air is sent to drying room. The scheme of wet air heat bypass of the patent solves the problem of low outlet air to some extent, but the return air temperature of drying room is low, the humidity of combined air is improved, the temperature of reheated air is limited, the humidity of hot air sent to drying room is relatively high, the overall drying effect is discounted, and the heat carried by condensate water is not well utilized, causing waste.

[0004] In view of the problem that the condensate water in the heat pump drying system is not effectively utilized and there is heat waste in the related technology, no effective solution has been proposed so far. UTILITY MODEL CONTENT

[0005] The utility model provides a kind of heat pump drying system, to at least solve the problem that condensate water in heat pump drying system in prior art is not effectively utilized, there is heat waste.

[0006] To solve the above technical problems, according to an aspect of an embodiment of the present application, a heat pump drying system is provided, which is applied to a drying room, and comprises: a dehumidification and reheating heat pump system, comprising: a first compressor, a first condenser, a first throttling device and a first evaporator connected in sequence; wherein the first evaporator is communicated with a return air outlet of the drying room, and is used for condensing return air of the drying room; after the humidity of the return air is reduced, the return air is introduced into an air inlet of the drying room; the first condenser is communicated with the air inlet of the drying room, and is used for heating the air entering the drying room; a heat storage water tank is located below the first evaporator, and is used for storing condensate water generated by the first evaporator; a heat recovery heat pump system, comprising: a second compressor, a second condenser, a second throttling device and a second evaporator connected in sequence; wherein the second evaporator is connected with the heat storage water tank, and is used for providing heat for the second condenser by using water in the heat storage water tank; and the second condenser is located on an air supply duct from the first evaporator to the first condenser, and is used for performing secondary heating on the return air entering the first condenser.

[0007] Further, the heat pump drying system further comprises: an air valve located on the air supply duct from the first evaporator to the first condenser, and used for adjusting the proportion of the return air directly entering the first condenser and flowing through the second condenser, so as to adjust the air inlet temperature of the drying room.

[0008] Further, the heat pump drying system further comprises: a heat exhaust cooling system, one end of which is communicated with a heat exhaust outlet of the drying room, and the other end of which is connected with the heat storage water tank, and is used for absorbing heat of the gas discharged from the heat exhaust outlet, and heating the water in the heat storage water tank.

[0009] Further, the heat exhaust cooling system comprises: a third compressor, a third condenser, a third throttling device and a third evaporator connected in sequence; wherein the third evaporator is located at the heat exhaust outlet of the drying room, and the third condenser is connected with the heat storage water tank, and is used for heating the water in the heat storage water tank by using heat of the third condenser.

[0010] Further, the heat exhaust cooling system comprises: an air-water heat exchanger located at the heat exhaust outlet of the drying room, and connected with the heat storage water tank, and used for absorbing heat of the gas at the heat exhaust outlet, and heating the water in the heat storage water tank.

[0011] Further, the second evaporator comprises a first sub-evaporator and a second sub-evaporator arranged in parallel.

[0012] Further, the first sub-evaporator is an air-side evaporator, and the second sub-evaporator is a water-side evaporator.

[0013] Further, the second sub-evaporator is connected with the heat storage water tank, and a first water pump is arranged on a pipeline connected with the second sub-evaporator and the heat storage water tank.

[0014] Further, a second water pump is arranged on a pipeline connected with the heat extraction cooling system and the heat storage water tank.

[0015] Further, the heat pump drying system further comprises a water collecting device arranged below the first evaporator and used for collecting the condensed water generated by the first evaporator.

[0016] In the heat pump drying system, the heat waste in the heat pump drying system is utilized, and a condensed water heat recovery heat pump drying system is provided, which comprises a water collecting device in addition to a dehumidification and reheating heat pump system and is used for collecting the condensed water generated by the evaporator of the dehumidification and reheating heat pump system. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is an optional structural schematic diagram of the heat pump drying system according to the embodiment of the utility model;

[0018] Figure 2 is another optional structural schematic diagram of the heat pump drying system according to the embodiment of the utility model.

[0019] MARKED FOR EXPLANATION:

[0020] 1, first compressor; 2, first condenser; 3, first throttling device; 4, first evaporator; 5, drying room; 6, water collecting device; 7, heat storage water tank; 8, second compressor; 9, second condenser; 10, second throttling device; 11, first sub-evaporator; 12, second sub-evaporator; 13, air valve; 14, third compressor; 15, third condenser; 16, third throttling device; 17, third evaporator; 18, gas-water heat exchanger; 19, second water pump; 20, first water pump. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the utility model clearer, the utility model will be described in further detail below in combination with the drawings. Obviously, the described embodiments are only some of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the utility model.

[0022] The terms used in the embodiments of the utility model are merely for the purpose of describing specific embodiments, and are not intended to limit the utility model. The singular forms "a", "said" and "the" used in the embodiments of the utility model and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. "Multiple" generally includes at least two.

[0023] It should be understood that the term "and / or" used herein is merely a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0024] It should be understood that although the terms first, second, third, etc. may be used in the embodiments of the utility model to describe the controllers, these controllers should not be limited to these terms. These terms are only used to distinguish the controllers connected to different devices. For example, without departing from the scope of the embodiments of the utility model, the first controller can also be called the second controller, and similarly, the second controller can also be called the first controller.

[0025] Depending on the context, the word "if" as used herein can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting". Similarly, depending on the context, the phrase "if determined" or "if detecting (a stated condition or event)" can be interpreted as "when determined" or "in response to determining" or "when detecting (a stated condition or event)" or "in response to detecting (a stated condition or event)".

[0026] It should also be noted that the terms "comprise", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the goods or devices comprising a series of elements not only include those elements, but also include other elements not explicitly listed, or include elements inherent to such goods or devices. Without more limitations, the element defined by the sentence "comprises a" does not exclude the existence of other identical elements in the goods or devices comprising the element.

[0027] The optional embodiments of the utility model are described in detail below with reference to the drawings.

[0028] Embodiment 1

[0029] In the preferred embodiment 1 of the utility model, a heat pump drying system is provided, which is applied to a drying room 5 for drying or baking.

[0030] Specifically, Figure 1 An optional structural schematic diagram of the heat pump drying system is shown, as shown in the figure, the heat pump drying system comprises: Figure 1

[0031] The dehumidification and reheating heat pump system comprises a first compressor 1, a first condenser 2, a first throttling device 3 and a first evaporator 4 connected in sequence; wherein the first evaporator 4 is communicated with the return air outlet of the drying room 5, is used for condensing the return air of the drying room 5, and the return air is communicated with the air inlet of the drying room 5 after the humidity of the return air is reduced; the first condenser 2 is communicated with the air inlet of the drying room 5, is used for heating the air entering the drying room 5; when the dehumidification and reheating heat pump system works, the air drawn out of the drying room 5 is dehumidified, a large amount of condensate water is generated, and the dehumidified air is reheated and then sent into the drying room 5; the first condenser 2 and the first evaporator 4 are located in two separate chambers, as shown in the figure, to avoid mixing of the return air and the inlet air, and to reduce the effect of the inlet air; Figure 1

[0032] The water collecting device 6 is located below the first evaporator 4 and is used for collecting the condensate water generated by the first evaporator 4; the water collecting device 6 can adopt a water collecting tray or other water collecting forms, as long as it can collect the condensate water and avoid leakage of the condensate water;

[0033] The hot water storage tank 7 is connected with the water outlet of the water collecting device 6 and is used for storing the condensate water;

[0034] The heat recovery heat pump system comprises a second compressor 8, a second condenser 9, a second throttling device 10 and a second evaporator connected in sequence; wherein the second evaporator is connected with the hot water storage tank 7 and is used for providing heat for the second condenser 9 by using the water in the hot water storage tank 7; the second condenser 9 is communicated with the air inlet of the drying room 5 and is used for heating the inlet air of the drying room 5 twice. Figure 1 As shown in the figure, the hot water storage tank 7 and the second evaporator are heat exchanged through a water channel to increase the temperature of the second evaporator, thereby providing higher temperature refrigerant for the second condenser 9, improving the heat exchange effect of the second condenser 9 and increasing the inlet air temperature. That is, the heat recovery heat pump system fully utilizes the heat in the condensate water, reheats the dehumidified and cooled air once, and then supplies the conventional dehumidification and reheating heat pump for secondary reheating, thereby improving the air supply heat and increasing the air supply temperature.

[0035] ​​In the above embodiment, in view of the heat waste in the heat pump drying system, a condensate heat recovery heat pump drying system is proposed. In addition to the dehumidification and reheating heat pump system, the system also includes a water collecting device for collecting the condensate water generated by the evaporator of the dehumidification and reheating heat pump system. In order to effectively utilize the collected condensate water, a heat storage water tank is also provided to store the condensate water, and a heat recovery heat pump system uses the water in the heat storage water tank to provide heat for the condenser thereof to perform secondary heating on the incoming air of the drying chamber to increase the incoming air temperature of the drying chamber. By coupling the condensate heat recovery heat pump system, the dehumidification condensate heat is fully utilized, the problem of low reheated air temperature after dehumidification and cooling of the heat pump drying system is avoided, the air supply heat and temperature are improved, the energy waste is greatly reduced, and the heating temperature is improved. The energy saving and drying process temperature control range of the heat pump drying system are improved.

[0036] As shown in Figure 1 , the system further includes: a wind valve 13 located on the air supply air duct of the first evaporator 4 to the first condenser 2, used to adjust the proportion of the air directly entering the first condenser 2 and the return air flowing through the second condenser 9, so as to adjust the incoming air temperature of the drying chamber 5. By adjusting the proportional opening size of the wind valve 13, the air flow through the second condenser 9 is adjusted, and then the proportion of the first reheating is determined, and the temperature regulation of the air before the secondary reheating is realized.

[0037] In order to further improve the energy utilization rate, the system further includes: a heat rejection cooling system, one end of which is in communication with the heat rejection outlet of the drying chamber 5, and the other end is connected with the heat storage water tank 7, used to absorb the heat of the gas discharged from the heat rejection outlet to heat the water in the heat storage water tank 7. The heat rejection cooling system utilizes the heat pump principle to absorb the heat in the drying chamber 5 when the drying chamber 5 needs to be cooled or the heat needs to be discharged after drying, and transfers the heat to the heat storage water tank 7 for subsequent reuse.

[0038] Optionally, as shown in Figure 1 , the heat rejection cooling system includes: a third compressor 14, a third condenser 15, a third throttling device 16 and a third evaporator 17 connected in sequence; wherein the third evaporator 17 is located at the heat rejection outlet of the drying chamber 5, and the third condenser 15 is connected with the heat storage water tank 7, used to heat the water in the heat storage water tank 7 by using the heat of the third condenser 15. The heat pump system can efficiently realize the collection and utilization of heat and improve the energy utilization rate.

[0039] Figure 2 Another optional embodiment of the heat rejection cooling system is shown in Figure 2As shown, the heat exhaust cooling system includes: a gas-water heat exchanger 18 located at the heat exhaust outlet of the drying room 5, the gas-water heat exchanger 18 is connected with the heat storage water tank 7, and is used for absorbing the heat of the heat exhaust outlet gas and heating the water in the heat storage water tank 7. The heat exhaust cooling heat pump storage system can be realized by an air-water heat exchanger, although the cooling speed is lower than that of the heat pump system, but no additional energy consumption is needed, which is beneficial to improve the energy efficiency of the overall system.

[0040] As shown in the figure, Figure 1 As shown, the second evaporator includes a first sub-evaporator 11 and a second sub-evaporator 12 arranged in parallel, the first sub-evaporator 11 is an air-side evaporator, and the second sub-evaporator 12 is a water-side evaporator, the second sub-evaporator 12 is connected with the heat storage water tank 7, and a first water pump 20 is arranged on the pipeline connected with the heat storage water tank 7; a second water pump 19 is arranged on the pipeline connected with the heat storage water tank 7. The water pump can accelerate the circulation of the water circuit, increase the water flow, and thus improve the heat exchange effect.

[0041] Next, the specific working process of the heat pump drying system will be described below. Figure 1

[0042] (1) Dehumidification and reheating heat pump system

[0043] The gaseous refrigerant enters the compressor through the suction port of the compressor, is compressed into high-pressure high-temperature gaseous refrigerant, enters the first condenser 2, heats the dehumidified and cooled air from the first evaporator 4 into dehumidified and higher-temperature air, and is sent into the drying room 5. The refrigerant is condensed into high-pressure liquid refrigerant at the same time; after being throttled and pressure-reduced by the first throttling valve, it enters the first evaporator 4.

[0044] After throttling, the refrigerant absorbs the heat of the high-humidity high-temperature air sucked from the drying room 5, forms low-pressure gaseous refrigerant, and the high-humidity high-temperature air flows through the fin surface of the first evaporator 4 to release heat and condense a large amount of medium-temperature condensed water, thereby realizing dehumidification and cooling.

[0045] The low-pressure gaseous refrigerant is sucked into the compressor again for compression, and the process is repeated.

[0046] (2) Heat recovery heat pump system coupled with condensate water

[0047] When the above-mentioned (1) dehumidification and reheating heat pump system is running, a large amount of medium-temperature condensed water is generated by the first evaporator 4, is collected by the water collecting disc, and is stored in the heat storage water tank 7.

[0048] ​The low-pressure and low-temperature gaseous refrigerant from the second evaporator is sucked into the compressor to form high-pressure and high-temperature gaseous refrigerant, enters the second condenser 9 to reheat the air dehumidified by the first evaporator 4, and the refrigerant is condensed into high-pressure liquid refrigerant; then the high-pressure liquid refrigerant is throttled and pressure-reduced and temperature-reduced by the second throttling valve and enters the second evaporator to absorb the heat of the condensed water in the heat storage water tank 7, and the refrigerant is evaporated into low-pressure and low-temperature gaseous refrigerant, which enters the compressor again, and the process is repeated.

[0049] The system considers that the heat of the condensed water in the heat storage water tank 7 is insufficient or the recoverable heat is very small, for example, the condensed water is relatively small or the temperature is relatively low in the early stage of drying, and a route of air-side evaporator is added to absorb sufficient heat from the air, and the flow can be distributed through the opening degree of the second throttling valve to realize sufficient primary reheating.

[0050] (3) Heat exhaust cooling system

[0051] In the drying process, there is a case that the drying room 5 needs to exhaust heat or cool down, at this time, the heat in the drying room 5 is fully utilized to be absorbed and transferred to the heat storage water tank 7 according to the heat pump principle, and the specific process is as follows:

[0052] The low-pressure gaseous refrigerant from the third evaporator 17 is sucked into the third compressor 14, is compressed into high-pressure and high-temperature gaseous refrigerant, enters the third condenser 15 to release heat to the water in the heat storage water tank 7, is condensed into high-pressure liquid refrigerant, is throttled and pressure-reduced and temperature-reduced, enters the third evaporator 17 to absorb the heat of the medium-high-temperature air in the drying room 5 and cool down the air, and the refrigerant is evaporated into low-pressure gaseous refrigerant again, enters the compressor again, and the process is repeated.

[0053] The heat pump drying system of the condensed water heat recovery utility model mainly comprises a drying room, a set of dehumidification and reheating heat pump system, a set of heat recovery heat pump system coupled with condensed water, a set of heat exhaust cooling heat pump heat storage system and the like.

[0054] The condensed water generated by dehumidification in the heat pump drying system is collected, the heat in the medium-temperature condensed water is fully absorbed through the coupled heat recovery system, high-temperature hot air is generated, the heat recovery in the heat pump drying system is realized, the air supply heat and temperature are improved, and the overall drying effect and energy saving performance of the system are improved.

[0055] The above-mentioned embodiment serial numbers of the utility model only serve for description, and do not represent the advantages and disadvantages of the embodiments.

[0056] In the above-mentioned embodiments of the utility model, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0057] In several embodiments provided in the present application, it should be understood that the disclosed technical contents can be implemented by other manners. Among them, the above-described device embodiments are only illustrative, for example, the division of the units can be a logical function division, and another division manner can be used in actual implementation, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units or modules shown or discussed can be indirect coupling or communication connection between the units or modules through some interfaces, and can be electrical or other forms.

[0058] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place or distributed on a plurality of units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0059] In addition, each functional unit in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0060] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various program code storage media.

[0061] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the application being indicated by the following claims.

[0062] It is to be understood that the application is not limited to the precise construction hereinafter described and as shown in the attached drawings, and that various changes in form and detail can be made therein without departing from the application. The scope of the application should only be limited by the appended claims.

Claims

1. A heat pump drying system, characterized in that, The heat pump drying system, used in drying rooms, includes: A dehumidification and reheat heat pump system includes: a first compressor, a first condenser, a first throttling device, and a first evaporator connected in sequence; wherein, the first evaporator is connected to the return air inlet of the drying room and is used to condense the return air of the drying room, reduce the humidity of the return air, and then introduce it into the air inlet of the drying room; the first condenser is connected to the air inlet of the drying room and is used to heat the air entering the drying room. A hot water storage tank, located below the first evaporator, is used to store the condensate produced by the first evaporator; A heat recovery heat pump system includes: a second compressor, a second condenser, a second throttling device, and a second evaporator connected in sequence; wherein, the second evaporator is connected to the hot water storage tank and is used to provide heat to the second condenser using water from the hot water storage tank; the second condenser is located on the air supply duct from the first evaporator to the first condenser and is used to perform secondary heating on the return air entering the first condenser.

2. The heat pump drying system according to claim 1, characterized in that, Also includes: An air valve, located on the air supply duct from the first evaporator to the first condenser, is used to adjust the ratio of return air directly entering the first condenser and flowing through the second condenser, thereby adjusting the inlet air temperature of the drying chamber.

3. The heat pump drying system according to claim 1, characterized in that, Also includes: The heat dissipation and cooling system is connected at one end to the heat dissipation outlet of the drying room and at the other end to the hot water storage tank. It is used to absorb the heat from the gas discharged from the heat dissipation outlet and heat the water in the hot water storage tank.

4. The heat pump drying system according to claim 3, characterized in that, The heat dissipation and cooling system includes: A third compressor, a third condenser, a third throttling device, and a third evaporator are connected in sequence; wherein, the third evaporator is located at the heat exhaust outlet of the drying chamber, and the third condenser is connected to the hot water storage tank for heating the water in the hot water storage tank using the heat from the third condenser.

5. The heat pump drying system according to claim 3, characterized in that, The heat dissipation and cooling system includes: A gas-water heat exchanger is located at the heat exhaust outlet of the drying chamber. The gas-water heat exchanger is connected to the hot water storage tank and is used to absorb the heat from the gas at the heat exhaust outlet to heat the water in the hot water storage tank.

6. The heat pump drying system according to claim 3, characterized in that, The second evaporator includes a first sub-evaporator and a second sub-evaporator arranged in parallel.

7. The heat pump drying system according to claim 6, characterized in that, The first sub-evaporator is an air-side evaporator, and the second sub-evaporator is a water-side evaporator.

8. The heat pump drying system according to claim 7, characterized in that, The second sub-evaporator is connected to the hot water storage tank, and a first water pump is installed on the pipeline connecting the second sub-evaporator and the hot water storage tank.

9. The heat pump drying system according to claim 3, characterized in that, A second water pump is installed on the pipeline connecting the heat dissipation and cooling system to the hot water storage tank.

10. The heat pump drying system according to claim 1, characterized in that, Also includes: A water collection device, located below the first evaporator, is used to collect the condensate produced by the first evaporator; wherein the outlet of the water collection device is connected to the inlet of the hot water storage tank, for introducing the condensate into the hot water storage tank.

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