Modularized heat pump low-temperature dehumidification drying method based on double-heating control

Abstract

The invention provides a modular heat pump low-temperature dehumidification drying system and method based on double-heating control, a to-be-dried product production line, a modular circulating unit and a modular double-heating unit are arranged in a drying chamber, the modular circulating unit is arranged on the side portion of the to-be-dried product production line, a detection unit is arranged on the modular circulating unit, and the modular double-heating unit is arranged on the modular circulating unit. The modularized double-heating unit and the detection unit establish communication with the control platform; the modular circulating unit and the modular double-heating unit can be modularly installed in an original drying chamber according to needs, installation is more flexible and convenient, and the construction cost is lower. The drying medium can be recycled by the modular circulating unit, so that the effective recovery of waste heat is realized, and the energy consumption is reduced; the modularized double-heating unit is provided with the heat pump condenser and the heater, only the heat pump condenser is operated when the humidity is low, energy consumption is reduced, the heat pump condenser and the heater are operated at the same time when the humidity is high, efficient dehumidification is achieved, and balance of energy consumption, efficiency and quality is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of food, biological products, and drug drying, and particularly to a modular heat pump low-temperature dehumidification drying method based on dual heating control. Background Art

[0002] Heat pump dryers are widely used in the processing of food, biological products, drugs, herbs, textiles, paper products, chemicals, beauty products, etc. In the field of food processing, they are used for drying and preserving fruits and vegetables. These systems utilize advanced heat pump technology to effectively dehydrate agricultural products while maintaining product quality. Industrial-scale heat pump dryers are used for high-efficiency dehydration of fruits and vegetables, maintaining their nutritional value, flavor, and quality while extending their shelf life.

[0003] Heat pump dryers use a closed-loop system to circulate low-temperature, low-humidity air over the surface of fruits and vegetables, extracting moisture through evaporation. This process operates at a lower temperature (usually 30 - 60 °C), which helps to maintain the nutritional value, flavor, color, and texture of agricultural products compared to traditional dryers. By controlling temperature, humidity, and air flow, heat pump dryers minimize thermal degradation, oxidation, and other processes that damage quality, resulting in dried fruits and vegetables with better appearance, taste, and nutrient retention, making them more appealing to consumers. Heat pumps recover and reuse energy from the drying air, significantly reducing energy consumption compared to traditional drying methods. This makes the process cost-effective and environmentally friendly in large-scale operations.

[0004] Existing industrial-scale heat pump dryers involve complex mechanical and electrical systems, including compressors, heat exchangers, and refrigerants, which require professional maintenance. Regular maintenance and repair costs are high, and trained technicians are needed, thus increasing operating expenses. Also, due to their large footprint, existing industrial-scale heat pump dryers require a large amount of space for installation, which limits their use in scenarios with limited space. To address the above problems, although simplifying industrial-scale heat pump dryers can effectively solve these issues, there is currently a lack of mature related technologies on the market, and the drying efficiency of some products with high humidity may be low after the heat pump drying system is simplified, unable to meet the drying requirements.

[0005] Therefore, there is an urgent need for a modular heat pump low-temperature dehumidification drying method based on dual heating control that can solve the above problems. Summary of the Invention

[0006] The object of the present invention is to provide a modular heat pump low-temperature dehumidification drying method based on dual heating control to solve the problems existing in the above prior art.

[0007] To achieve the above object, the present invention provides the following solution:

[0008] The present invention provides a modular heat pump low-temperature dehumidification drying system based on dual heating control, comprising:

[0009] A drying chamber, in which a production line of products to be dried is provided;

[0010] A modular circulation unit, which is arranged in the drying chamber and correspondingly arranged at the side of the production line of products to be dried, and is used for low-temperature dehumidification drying of the products to be dried through a drying medium;

[0011] A modular dual heating unit, which is connected to the modular circulation unit and is used for adjusting the temperature and humidity of the drying medium;

[0012] A detection unit, which is arranged on the modular circulation unit and is used for detecting the air outlet wind speed, air outlet temperature, air outlet humidity, air suction wind speed, air suction temperature and air suction humidity;

[0013] A control platform, which establishes communication with the modular dual heating unit and the detection unit and is used for controlling the operation of the low-temperature dehumidification drying system.

[0014] Preferably, an installation platform is provided at the upper part of the drying chamber, and the modular circulation unit is installed on the installation platform.

[0015] Preferably, the modular circulation unit includes an air outlet pipeline and a return air pipeline. The air inlet end of the air outlet pipeline is connected to the modular dual heating unit. The air outlet end of the air outlet pipeline is provided with a plurality of air outlets side by side. The air inlet end of the return air pipeline is provided with a plurality of air suction openings side by side. The air suction openings are arranged opposite to the air outlets. The air outlet end of the return air pipeline is connected to the modular dual heating unit.

[0016] Preferably, a pressure balance plate is arranged in the air outlet pipeline.

[0017] Preferably, the air suction opening is connected to the return air pipeline through a flexible bellows.

[0018] Preferably, the modular dual heating unit includes a processing chamber. The air outlet pipeline and the return air pipeline are respectively connected to both ends of the processing chamber. A variable-frequency blower is arranged between the air outlet pipeline and the processing chamber. A variable-frequency air suction fan is arranged between the return air pipeline and the processing chamber. A heat pump condenser and a heater are oppositely arranged in the middle of the processing chamber. The variable-frequency blower, the variable-frequency air suction fan, the heat pump condenser and the heater all establish communication with the control platform.

[0019] Preferably, the detection unit includes an air outlet wind speed sensor, an air outlet temperature sensor, an air outlet humidity sensor, a return air wind speed sensor, a return air temperature sensor, and a return air humidity sensor. The air outlet wind speed sensor, the air outlet temperature sensor, and the air outlet humidity sensor are all arranged on the air outlet, and the return air wind speed sensor, the return air temperature sensor, and the return air humidity sensor are all arranged on the air suction port.

[0020] The present invention also provides a modular heat pump low-temperature dehumidification and drying method based on dual heating control, including the following steps:

[0021] S1. System initialization, presetting a humidity threshold, a humidity hysteresis interval, a safety temperature threshold, an initial drying temperature, and an initial drying wind speed through a control platform;

[0022] S2. The control platform controls the operation of the modular dual heating unit. In the initial operation stage, only the heat pump condenser operates, and the heater is default closed;

[0023] S3. The air outlet wind speed sensor, the air outlet temperature sensor, and the air outlet humidity sensor collect the parameters of the drying medium at the air outlet in real time and feedback them to the control platform. The control platform adjusts the states of the heat pump condenser and the variable frequency blower in real time according to the preset initial drying temperature and initial drying wind speed;

[0024] S4. The return air wind speed sensor, the return air temperature sensor, and the return air humidity sensor collect the parameters of the drying medium at the air suction port in real time and feedback them to the control platform. When the return air humidity collected by the return air humidity sensor is greater than the sum of the humidity threshold and the humidity hysteresis interval, the control platform calculates the relationship between the drying rate and the humidity change according to the humidity dynamic model, judges whether to start the combined operation of the heater, and the control platform controls the system operation according to the judgment result.

[0025] Preferably, in step S4, the relationship between the drying rate and the humidity change is:

[0026] dH / dt = -α·(P total -β·H current ) ;

[0027] Wherein, α is the drying efficiency coefficient of the product to be dried, β is the humidity attenuation coefficient under the influence of the wind speed, P total is the total heating power, and H current is the humidity collected in real time.

[0028] Preferably, it further includes: S5. When the air outlet temperature sensor detects that the air outlet temperature is greater than the safety temperature threshold, the control platform controls the heater to be forcibly closed.

[0029] The present invention has achieved the following beneficial technical effects compared with the prior art:

[0030] A modular heat pump low-temperature dehumidification drying system and method based on dual heating control provided by the present invention. A production line of products to be dried, a modular circulation unit, and a modular dual heating unit are arranged in a drying chamber. The modular circulation unit is arranged on the side of the production line of products to be dried. A detection unit is provided on the modular circulation unit. Both the modular dual heating unit and the detection unit are in communication with a control platform. The modular circulation unit and the modular dual heating unit can be modularly installed in the original drying chamber as needed, with more flexible and convenient installation and lower construction costs. Moreover, the modular circulation unit can recycle the drying medium, effectively recover waste heat, and reduce energy consumption. The modular dual heating unit has a heat pump condenser and a heater. When the humidity is low, only the heat pump condenser operates to reduce energy consumption. When the humidity is high, both the heat pump condenser and the heater operate to efficiently dehumidify, achieving a balance among energy consumption, efficiency, and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0032] Figure 1 It is a schematic structural diagram of a modular heat pump low-temperature dehumidification drying system provided by the present invention;

[0033] In the figure: 1: drying chamber, 11: installation platform, 2: modular circulation unit, 21: air outlet pipeline, 22: return air pipeline, 23: air outlet, 24: air suction port, 25: pressure balance plate, 26: flexible bellows, 3: modular dual heating unit, 31: treatment chamber, 32: variable-frequency blower, 33: variable-frequency suction fan, 34: heat pump condenser, 35: heater. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0035] The purpose of the present invention is to provide a modular heat pump low-temperature dehumidification drying system and method based on dual heating control to solve the problems existing in the prior art.

[0036] To make the above objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Embodiment 1:

[0038] This embodiment provides a modular heat pump low-temperature dehumidification drying system based on dual heating control. As Figure 1 shown, it includes:

[0039] A drying chamber 1, in which a production line of products to be dried is provided;

[0040] A modular circulation unit 2, which is arranged in the drying chamber 1 and correspondingly set on the side of the production line of products to be dried, and is used for low-temperature dehumidification drying of the products to be dried through a drying medium;

[0041] A modular dual heating unit 3, which is connected to the modular circulation unit 2 and is used for adjusting the temperature and humidity of the drying medium;

[0042] A detection unit, which is arranged on the modular circulation unit 2 and is used for detecting the outlet air velocity, outlet air temperature, outlet air humidity, inlet air velocity, inlet air temperature, and inlet air humidity;

[0043] A control platform, which establishes communication with the modular dual heating unit 3 and the detection unit and is used for controlling the operation of the low-temperature dehumidification drying system.

[0044] By adopting the above technical solutions, both the modular circulation unit 2 and the modular dual heating unit 3 can be modularly installed as needed in the original drying chamber 1, with more flexible and convenient installation and lower construction costs; moreover, the modular circulation unit 2 can recycle the drying medium, effectively recovering waste heat and reducing energy consumption; the modular dual heating unit 3 has a heat pump condenser and a heater. When the humidity is low, only the heat pump condenser operates to reduce energy consumption, and when the humidity is high, both the heat pump condenser and the heater operate to achieve efficient dehumidification, realizing the balance of energy consumption, efficiency, and quality.

[0045] As an implementation manner, an installation platform 11 is provided on the upper part of the drying chamber 1, and the modular circulation unit 2 is installed on the installation platform 11.

[0046] By adopting the above technical solutions, the installation difficulty of the heat pump drying system is effectively reduced, and the installation space is saved.

[0047] As an implementation, the modular circulation unit 2 includes an air outlet pipeline 21 and an air return pipeline 22. The air inlet end of the air outlet pipeline 21 is connected to the modular double heating unit 3. A plurality of air outlets 23 are arranged side by side at the air outlet end of the air outlet pipeline 21. The air outlet pipeline 21 can be made of UPVC material, which can transport high-pressure and high-temperature dry air and evenly send it out through the plurality of air outlets 23. A plurality of air inlets 24 are arranged side by side at the air inlet end of the air return pipeline 22. The air inlets 24 are arranged opposite to the air outlets 23. The air outlet end of the air return pipeline 22 is connected to the modular double heating unit 3, so as to suck away the wet and cold air after replacing the moisture and recycle it.

[0048] By adopting the above technical solution, the dry matrix is blown onto the product to be dried through the plurality of air outlets 22, so as to effectively replace the moisture in the product to be dried, and realize the uniform and efficient drying of the product to be dried. Since the replaced drying medium still has a certain amount of waste heat, the wet and cold air containing moisture can be completely sucked away through the air inlets 24, avoiding the rehumidification of the product to be dried, and at the same time realizing waste heat recovery.

[0049] As an implementation, a pressure balance plate 25 is arranged in the air outlet pipeline 21.

[0050] By adopting the above technical solution, the pressure balance plate 25 can extend the path of the drying medium, so that the pressures at the plurality of air outlets 23 are the same, avoiding uneven wind force caused by unbalanced pressure.

[0051] As an implementation, the air inlet 24 and the air return pipeline 22 are connected through a flexible bellows 26.

[0052] By adopting the above technical solution, the flexible bellows 26 is convenient for adjusting the length and direction, so as to ensure the recovery effect.

[0053] As an implementation, the modular double heating unit 3 includes a processing chamber 31. The air outlet pipeline 21 and the air return pipeline 22 are respectively connected to both ends of the processing chamber 31. A variable frequency blower 32 is arranged between the air outlet pipeline 21 and the processing chamber 31, and a variable frequency suction fan 33 is arranged between the air return pipeline 22 and the processing chamber 31. A heat pump condenser 34 and a heater 35 are arranged opposite to each other in the middle of the processing chamber 31. The variable frequency blower 32, the variable frequency suction fan 33, the heat pump condenser 34 and the heater 35 are all in communication with the control platform.

[0054] By adopting the above technical solution, only the heat pump condenser 34 operates when the humidity is low, reducing energy consumption. When the humidity is high, both the heat pump condenser 34 and the heater 35 operate, achieving high-efficiency dehumidification and realizing the balance of energy consumption, efficiency and quality.

[0055] As an implementation manner, the detection unit includes an air outlet wind speed sensor, an air outlet temperature sensor, an air outlet humidity sensor, a return air wind speed sensor, a return air temperature sensor, and a return air humidity sensor. The air outlet wind speed sensor, the air outlet temperature sensor, and the air outlet humidity sensor are all arranged on the air outlet 23, and the return air wind speed sensor, the return air temperature sensor, and the return air humidity sensor are all arranged on the air suction port 24.

[0056] By adopting the above technical solution, the temperature, air volume, and humidity of the dry hot air and the wet cold air can be collected in real time, thereby providing a basis for dynamic control.

[0057] This embodiment also provides a modular heat pump low-temperature dehumidification and drying method based on dual heating control, including the following steps:

[0058] S1. System initialization, presetting a humidity threshold, a humidity hysteresis interval, a safety temperature threshold, an initial drying temperature, and an initial drying wind speed through a control platform;

[0059] S2. The control platform controls the modular dual heating unit 3 to operate. In the initial operation stage, only the heat pump condenser 34 operates, and the heater 35 is default closed;

[0060] S3. The air outlet wind speed sensor, the air outlet temperature sensor, and the air outlet humidity sensor collect the parameters of the drying medium at the air outlet 23 in real time and feedback them to the control platform. The control platform adjusts the states of the heat pump condenser 34 and the variable frequency blower 32 in real time according to the preset initial drying temperature and initial drying wind speed;

[0061] S4. The return air wind speed sensor, the return air temperature sensor, and the return air humidity sensor collect the parameters of the drying medium at the air suction port 24 in real time and feedback them to the control platform. When the return air humidity collected by the return air humidity sensor is greater than the sum of the humidity threshold and the humidity hysteresis interval, the control platform calculates the relationship between the drying rate and the humidity change according to the humidity dynamic model, judges whether to start the combined operation of the heater 35, and the control platform controls the system operation according to the judgment result; wherein,

[0062] The relationship between the drying rate and the humidity change is:

[0063] dH / dt = -α·(P total - β·H current );

[0064] wherein, α is the drying efficiency coefficient of the product to be dried, β is the humidity attenuation coefficient under the influence of the wind speed, P total is the total heating power, and H current is the humidity collected in real time;

[0065] S5. When the air outlet temperature sensor detects that the air outlet temperature is greater than the safety temperature threshold, the control platform controls the heater to be forcibly closed.

[0066] The present invention uses specific examples to illustrate the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A modular heat pump low-temperature dehumidification drying system based on dual heating control, characterized in that: Comprising: A drying chamber (1), in which a production line of products to be dried is provided; A modular circulation unit (2), which is arranged in the drying chamber (1) and correspondingly arranged on the side of the production line of products to be dried, and is used for low-temperature dehumidification drying of the products to be dried by a drying medium; A modular dual heating unit (3), which is connected to the modular circulation unit (2) and is used for adjusting the temperature and humidity of the drying medium; A detection unit, which is arranged on the modular circulation unit (2) and is used for detecting the outlet air velocity, outlet air temperature, outlet air humidity, inlet air velocity, inlet air temperature and inlet air humidity; A control platform, which establishes communication with the modular dual heating unit (3) and the detection unit and is used for controlling the operation of the low-temperature dehumidification drying system.

2. The modular heat pump low-temperature dehumidification and drying system based on dual heating control according to claim 1, characterized in that: An installation platform (11) is provided at the upper part of the drying chamber (1), and the modular circulation unit (2) is installed on the installation platform (11).

3. The modular heat pump low-temperature dehumidification and drying system based on dual heating control according to claim 1, characterized in that: The modular circulation unit (2) includes an outlet air pipeline (21) and a return air pipeline (22). The inlet end of the outlet air pipeline (21) is connected to the modular dual heating unit (3). A plurality of outlet air ports (23) are arranged side by side at the outlet end of the outlet air pipeline (21). A plurality of inlet air ports (24) are arranged side by side at the inlet end of the return air pipeline (22). The inlet air ports (24) are arranged opposite to the outlet air ports (23). The outlet end of the return air pipeline (22) is connected to the modular dual heating unit (3).

4. The modular heat pump low-temperature dehumidification and drying system based on dual heating control according to claim 3, characterized in that: A pressure balance plate (25) is arranged in the outlet air pipeline (21).

5. The modular heat pump low-temperature dehumidification and drying system based on dual heating control according to claim 3, wherein: The inlet air ports (24) and the return air pipeline (22) are connected through a flexible bellows (26).

6. The modular heat pump low-temperature dehumidification drying system based on dual heating control according to claim 3, characterized in that: The modular dual heating unit (3) includes a processing chamber (31). The outlet air pipeline (21) and the return air pipeline (22) are respectively connected to both ends of the processing chamber (31). A variable frequency blower (32) is arranged between the outlet air pipeline (21) and the processing chamber (31). A variable frequency suction fan (33) is arranged between the return air pipeline (22) and the processing chamber (31). A heat pump condenser (34) and a heater (35) are oppositely arranged in the middle of the processing chamber (31). The variable frequency blower (32), the variable frequency suction fan (33), the heat pump condenser (34) and the heater (35) are all in communication with the control platform.

7. The modular heat pump low-temperature dehumidification and drying system based on dual heating control according to claim 6, characterized in that: The detection unit includes an outlet air velocity sensor, an outlet air temperature sensor, an outlet air humidity sensor, a return air velocity sensor, a return air temperature sensor and a return air humidity sensor. The outlet air velocity sensor, the outlet air temperature sensor and the outlet air humidity sensor are all arranged on the outlet air ports (23). The return air velocity sensor, the return air temperature sensor and the return air humidity sensor are all arranged on the inlet air ports (24).

8. Modular heat pump low-temperature dehumidification drying method based on dual heating control, characterized in that: Including the following steps: S1. System initialization, presetting a humidity threshold, a humidity hysteresis interval, a safety temperature threshold, an initial drying temperature and an initial drying air velocity through the control platform; S2. The control platform controls the operation of the modular dual heating unit (3). In the initial operation stage, only the heat pump condenser (34) operates, and the heater (35) is default closed. S3. The air outlet wind speed sensor, air outlet temperature sensor, and air outlet humidity sensor collect the parameters of the drying medium at the air outlet (23) in real time and feedback them to the control platform. The control platform adjusts the states of the heat pump condenser (34) and the variable frequency blower (32) in real time according to the preset initial drying temperature and initial drying wind speed. S4. The return air wind speed sensor, return air temperature sensor, and return air humidity sensor collect the parameters of the drying medium at the air inlet (24) in real time and feedback them to the control platform. When the return air humidity collected by the return air humidity sensor is greater than the sum of the humidity threshold and the humidity hysteresis interval, the control platform calculates the relationship between the drying rate and the humidity change according to the humidity dynamic model, determines whether to start the combined operation of the heater (35), and the control platform controls the system operation according to the judgment result.

9. The modular heat pump low-temperature dehumidification and drying method based on dual heating control according to claim 8, characterized in that: In step S4, the relationship between the drying rate and the humidity change is: dH / dt = -α·(P total - β·H current ); Among them, α is the drying efficiency coefficient of the product to be dried, β is the humidity attenuation coefficient under the influence of wind speed, P total is the total heating power, and H current is the humidity collected in real time.

10. The modular heat pump low-temperature dehumidification drying method based on dual heating control according to claim 8, characterized in that: It also includes: S5. When the air outlet temperature sensor detects that the air outlet temperature is greater than the safety temperature threshold, the control platform controls the heater (35) to be forcibly closed.

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