CN210220598U

CN210220598U - Closed loop heat pump dryer

Info

Publication number: CN210220598U
Application number: CN201920872453.1U
Authority: CN
Inventors: Yongjun Zhu; 朱勇俊; Wei Li; 李炜; Jiajia Wang; 王佳佳; Shuqian Zhang; 张树前; Xiaojun Yuan; 袁晓军
Original assignee: Zhejiang Zhongguang Electric Appliances Co Ltd
Current assignee: Zhejiang Zhongguang Electric Appliance Group Co Ltd
Priority date: 2019-06-11
Filing date: 2019-06-11
Publication date: 2020-03-31
Anticipated expiration: 2029-06-11

Abstract

The utility model provides a closed loop heat pump drying-machine belongs to heat pump technical field. It has solved the poor scheduling problem of prior art design stoving effect. The closed-loop heat pump dryer comprises a casing, wherein a circulating heating system comprising a compressor, a condenser and an evaporator is arranged in the casing, the compressor is electrically connected with a controller, an exhaust outlet for outputting hot air made by the heating system to the outside by an exhaust fan arranged in the casing is formed in the casing, and an air return opening for allowing hot and humid air which is already heated to the outside to enter and a secondary heat exchanger for carrying out heat exchange with the hot air coming from the air return opening for twice are further formed in the casing. This closed loop heat pump drying-machine's advantage lies in: the ventilating plate is provided with a plurality of ventilating holes, the effect of increasing the circulating air volume of the condenser and reducing the running power of the unit can be achieved through 10% -20% of ventilating volume, the increase of the circulating air volume is more beneficial to the drying speed of materials, the power is reduced, and the running cost of the unit is more energy-saving.

Description

Closed loop heat pump dryer

Technical Field

The utility model belongs to the technical field of the heat pump, especially, relate to a closed loop heat pump drying-machine.

Background

The air energy heat pump dryer mainly comprises an open-loop type dryer, a direct-heating type dryer and a closed-loop type dryer, wherein the open-loop type dryer has the advantages that the temperature is quickly increased, but the drying materials are mainly subjected to moisture removal, a large amount of heat is discharged while the moisture removal is carried out, and the heat energy is wasted; the direct-heating dryer is influenced by the ambient temperature, heat is directly discharged after passing through materials during drying, and a large amount of heat energy is wasted; the closed loop type dryer dries materials mainly by means of dehumidification, basically realizes zero emission, prevents the materials from being polluted by the external environment, has long temperature rise time and high water removal efficiency.

Just because the closed-loop air energy dryer has the advantages, the application of the dryer is more and more, the structure of various manufacturers is similar, but the functions are different, and the existing closed-loop dryer has the following defects: because a sensible heat exchanger is not additionally arranged in the partial closed-loop type dryer, a large amount of cold energy is consumed to eliminate the sensible heat of air in the dehumidification process, and therefore the effective utilization efficiency of the evaporator for dehumidification is too low; in addition, although the sensible heat exchange device is additionally arranged in the existing partial closed-loop dryer, the current situation that temperature is continuously increased and constant temperature cannot be kept exists, so that the relative humidity in the drying room is lower and the load is smaller when the materials are dried more and more in the later drying period, and the temperature of the unit can be continuously increased at the moment, therefore, the existing closed-loop dryer cannot well meet the drying process requirements of temperature control and dehumidification.

SUMMERY OF THE UTILITY MODEL

The utility model aims at the above-mentioned problem, provide a reasonable in design, provide a dehumidification more high-efficient, the accuse temperature is more stable, collects the dehumidification, accuse temperature closed loop heat pump drying-machine as an organic whole.

In order to achieve the above purpose, the utility model adopts the following technical proposal: the utility model discloses a closed loop heat pump drying-machine, including the casing, be equipped with in the casing by the circulation heating system who comprises compressor, condenser and evaporimeter, the compressor is connected with the controller electricity, offers on the casing and supplies the hot-blast output to outside air exit that makes this heating system by the exhaust fan of locating in the casing, its characterized in that: the shell is also provided with a return air inlet for allowing the outside hot and humid air to enter and a secondary heat exchanger for carrying out secondary heat exchange with the hot air coming from the return air inlet, the hot air entering the return air inlet carries out primary heat exchange with the secondary heat exchanger, then reenters the secondary heat exchanger after flowing through an evaporator communicated with the secondary heat exchanger and carries out secondary heat exchange with the secondary heat exchanger, the shell is also internally provided with a ventilation plate which enables part of the hot air entering the return air inlet to directly flow into the condenser without passing through the secondary heat exchanger, the ventilation plate is provided with a plurality of ventilation holes, and the hot air which has finished the secondary heat exchange and the hot air flowing through the ventilation holes are mixed and enter the condenser communicated with the ventilation plate.

Preferably, at least one set of electric heating elements for heating the air coming out of the condenser is arranged between the condenser and the exhaust fan, and each electric heating element is electrically connected with the controller respectively.

Preferably, the number of electric heating elements is 2 groups. The size of electric heating is determined according to the temperature of the drying room, and the adjusting capability of the hot air temperature of the dryer is provided.

Preferably, the size of the sum of the sectional areas of all the vent holes is calculated on the basis that the maximum total ventilation amount required to flow through all the vent holes is 10 to 20% of the total flow amount of the hot wind entering from the return air inlet.

Preferably, the secondary heat exchanger is a sensible heat exchanger.

Preferably, the casing is further provided with a fresh air inlet for allowing outside air to enter, the fresh air inlet is provided with a fresh air valve for controlling the outside air entering flow, and outside air entering from the fresh air inlet is mixed with low-temperature dry air which flows through the evaporator after being subjected to primary heat exchange with the secondary heat exchanger and then enters the secondary heat exchanger again to perform secondary heat exchange.

Preferably, the fresh air valve is electrically connected to the controller. The automatic control of the fresh air intake is possible.

Compared with the prior art, the closed-loop heat pump dryer has the advantages that: 1. the ventilation plate is provided with a plurality of ventilation holes, so that the effects of increasing the circulating air quantity of the condenser and reducing the operating power of the unit can be achieved by 10-20% of ventilation quantity, the increase of the circulating air quantity is more beneficial to the drying speed of materials, the power is reduced, and the operating cost of the unit is more energy-saving; 2. fresh air is introduced into the system through the fresh air inlet and the fresh air valve, and is preheated through the secondary heat exchanger, so that the temperature of the drying room is prevented from greatly fluctuating, the energy input is saved, and the drying materials are more energy-saving and economical; 3. when the temperature of the drying room does not rise in sections, if the humidity does not meet the requirement, the unit can work all the time, the temperature can be continuously raised, the temperature deviates from the normal drying temperature of the materials, the drying process is damaged, and even the problem of material baking is caused; 4. the fresh air valve and the fresh air port can introduce fresh air to replace high-humidity air in the drying room when the humidity of the drying room is too high, so that the function of strong moisture removal is achieved; 5. through above-mentioned scheme, effectively solved the problem that current closed loop heat pump constantly heaies up, it is more energy-conserving to dry, reaches the dry purpose of constant temperature dehumidification.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 provides a schematic structural diagram of an embodiment of the present invention.

Fig. 2 provides a schematic structural diagram of a ventilation board in an embodiment of the present invention.

In the figure, a casing 101, a compressor 102, a condenser 103, an evaporator 104, a controller 105, an exhaust fan 106, an air return 107, a secondary heat exchanger 108, an air ventilation plate 109, an air ventilation hole 110, an electric heating element 111, a fresh air opening 112, a fresh air valve 113, an air exhaust opening 114, a first flow chamber 115, a second flow chamber 116, a third flow chamber 117, and a fourth flow chamber 118.

As shown in fig. 1 to 2, the embodiment of the present closed loop heat pump dryer includes, but is not limited to, the following examples.

Example 1

The closed loop heat pump dryer comprises a machine shell 101, a circulation heating system composed of a compressor 102, a condenser 103 and an evaporator 104 is arranged in the machine shell 101, the compressor 102 is electrically connected with a controller 105, an exhaust outlet 114 for outputting hot air made by the heating system to the outside by an exhaust fan 106 arranged in the machine shell 101 is arranged on the machine shell 101, a return air inlet 107 for entering hot and humid air which is used for the outside and a secondary heat exchanger 108 for carrying out twice heat exchange with the hot air entering from the return air inlet 107 are also arranged on the machine shell 101, the hot and humid air is generally but not limited to a drying room from the hot air sent out by the dryer to the outside, the hot and humid air generated after the temperature of materials in the drying room is raised, the hot air entering the return air inlet 107 carries out the first heat exchange with the secondary heat exchanger 108, then enters the secondary heat exchanger 108 again after flowing through the evaporator 104 communicated with the secondary heat exchanger 108 and carries out the second heat exchange with the secondary heat exchanger, the evaporator 104 is used for dehumidifying the hot air with high humidity entering from the air return port 107, a ventilation plate 109 is further arranged in the shell 101, the part of the hot air entering the air return port 107 does not pass through the secondary heat exchanger 108 but directly flows into the condenser 103, a plurality of ventilation holes 110 are formed in the ventilation plate 109, and the hot air after twice heat exchange and the hot air flowing through the ventilation holes 110 are mixed and enter the condenser 103 communicated with the ventilation holes 110.

Specifically, a first flow chamber 115 in which a relatively independent supply air flow is enclosed by the casing 101, the ventilation board 109 and the secondary heat exchanger 108 is provided in the casing 101, the return air inlet 107 is communicated with the first flow chamber 115, a second flow chamber 116 in which a second relatively independent supply air flow is enclosed by the casing 101, the ventilation board 109, the condenser 103 and the secondary heat exchanger 108, a third flow chamber 117 in which a third relatively independent supply air flow is enclosed by the casing 101, the evaporator 104 and the secondary heat exchanger 108, and a fourth flow chamber 118 in which a fourth relatively independent supply air flow is enclosed by the casing 101, the evaporator 104 and the secondary heat exchanger 108.

Alternatively, at least one set of electric heating elements 111 for heating the air exiting from the condenser 103 is disposed between the condenser 103 and the exhaust fan 106, wherein the electric heating elements 111 are generally, but not limited to, electric heating pipes, and each electric heating element 111 is electrically connected to the controller 105.

Alternatively, the number of the electric heating members 111 is 2 groups. The size of the electric heating is determined according to the temperature of the drying room, the adjustment capability of the hot air temperature of the dryer is provided, and furthermore, a group of electric heating elements 111 can be arranged at the outlet end of the exhaust fan 106.

Alternatively, the total size of the sectional areas of all the vents 110 is calculated based on the requirement that the maximum total ventilation amount flowing through all the vents 110 is 10-20% of the total flow amount of the hot wind entering from the return air opening 107.

Alternatively, the secondary heat exchanger 108 is a sensible heat exchanger.

The working principle is as follows: through the reverse carnot cycle principle, the high temperature and high humidity wind outside the casing 101 enters the first flow chamber 115 from the air return port 107, flows through the secondary heat exchanger 108, realizes the first heat exchange, becomes low temperature and high humidity wind, at which the temperature of the wind is reduced to approach the dew point, then enters the third flow chamber 117, then flows through the evaporator 104, discharges condensed water through the evaporator 104 to realize the dehumidification function of the low temperature and high humidity wind, thereby achieving the low temperature and low humidity wind, then flows into the fourth flow chamber 118, then flows through the secondary heat exchanger 108 to perform the second heat exchange to increase the temperature of the low temperature and low humidity wind, thereby becoming high temperature and low humidity wind, then enters the second flow chamber 116 to mix with the high temperature and high humidity wind which is not heat exchanged, then enters the condenser 103 to further increase the temperature of the entering wind, the electric heating element 111 can be opened as required to heat the hot wind coming out from the condenser 103, finally, the hot air is conveyed to a place needing heating outside through the exhaust fan 106, which generally can be but is not limited to a drying room, the hot air enters the first flowing chamber 115 through the air return opening 107 again after being thermally utilized, so that continuous cyclic dehumidification and temperature rise are realized, and materials in the drying room are separated out continuously in a manner of discharging condensed water, so that the purpose of drying is achieved.

Example 2

This embodiment is substantially the same as embodiment 1 except that: the casing 101 is further provided with a fresh air inlet 112 for allowing outside air to enter, the fresh air inlet 112 is provided with a fresh air valve 113 for controlling the outside air entering flow, the outside air entering from the fresh air inlet 112 is mixed with the hot air which has undergone the first heat exchange with the secondary heat exchanger 108 and then flows through the evaporator 104 to enter the secondary heat exchanger 108 again for the second heat exchange, and the fresh air inlet 112 is communicated with the fourth flow chamber 118.

Alternatively, the fresh air valve 113 is electrically connected to the controller 105. The automatic control of the fresh air intake is possible.

The working principle is as follows: the operation principle is basically the same as that of embodiment 1, except that the low-temperature fresh air entering from the fresh air port 112 and the fresh air valve 113 is introduced into the fourth flowing chamber 118, so that the low-temperature fresh air and the low-temperature and low-heat air flowing out from the evaporator 104 enter the secondary heat exchanger 108 to perform the second heat exchange, and the purpose of better controlling the temperature of the air conveyed by the dryer is realized by increasing the low-temperature air quantity, which is beneficial to avoiding the situation that the temperature of the hot air is too high under the condition that the moisture of the material is still high when the material is dried, thereby deviating the normal drying temperature of the material and even causing the problem of material burning.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Although the terms of the cabinet 101, the compressor 102, the condenser 103, the evaporator 104, the controller 105, the exhaust fan 106, the return air opening 107, the secondary heat exchanger 108, the vent plate 109, the vent hole 110, the electric heating element 111, the fresh air opening 112, the fresh air valve 113, the exhaust opening 114, the first flow chamber 115, the second flow chamber 116, the third flow chamber 117, the fourth flow chamber 118, etc., are used more herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed in a manner that is inconsistent with the spirit of the invention.

Claims

1. The utility model provides a closed loop heat pump drying-machine, includes casing (101), casing (101) in be equipped with by the circulation heating system who comprises compressor (102), condenser (103) and evaporimeter (104), compressor (102) be connected with controller (105) electricity, casing (101) on offer and supply by exhaust fan (106) of locating in casing (101) with hot-blast output to outside air exit (114) that this heating system made, its characterized in that: the shell (101) is also provided with an air return opening (107) for the entry of the outside hot and humid air which is used for heat utilization and a secondary heat exchanger (108) for carrying out heat exchange twice with the hot air entering from the air return opening (107), after the first heat exchange is carried out between the hot air entering the air return opening (107) and the secondary heat exchanger (108), then enters the secondary heat exchanger (108) again after flowing through the evaporator (104) communicated with the secondary heat exchanger and carries out secondary heat exchange with the secondary heat exchanger, a ventilation plate (109) which leads the part of hot air entering the air return opening (107) to directly flow into the condenser (103) without passing through the secondary heat exchanger (108) is also arranged in the shell (101), the ventilation plate (109) is provided with a plurality of ventilation holes (110), and the hot air which has completed twice heat exchange and the hot air flowing through the ventilation holes (110) are mixed and enter the condenser (103) communicated with the hot air.

2. A closed loop heat pump dryer as claimed in claim 1, characterized in that at least one set of electric heating elements (111) for heating the air coming out of the condenser (103) is arranged between the condenser (103) and the exhaust fan (106), each of said electric heating elements (111) being electrically connected to the controller (105), respectively.

3. Closed loop heat pump dryer as claimed in claim 2, characterized in that the number of electric heating elements (111) is 2 groups.

4. The closed loop heat pump dryer of claim 1, wherein the size of the sum of the sectional areas of all the vents (110) is calculated based on the requirement that the maximum total ventilation amount flowing through all the vents (110) is 10-20% of the total flow amount of the hot wind entering from the return air inlet (107).

5. A closed loop heat pump dryer as claimed in claim 1 wherein said secondary heat exchanger (108) is a sensible heat exchanger.

6. The closed loop heat pump dryer as claimed in any one of claims 1 to 5, wherein the casing (101) is further provided with a fresh air inlet (112) for allowing outside air to enter, the fresh air inlet (112) is provided with a fresh air valve (113) for controlling an outside air entering flow, and outside air entering from the fresh air inlet (112) is mixed with the low-temperature dry air which has undergone the first heat exchange with the secondary heat exchanger (108) and then flows through the evaporator (104) to reenter the secondary heat exchanger (108) for performing the second heat exchange.

7. A closed loop heat pump dryer as claimed in claim 6 wherein said fresh air valve (113) is electrically connected to the controller (105).