阅读说明：本技术 干燥装置和干燥方法 (Drying device and drying method ) 是由 王寿权 尹凤交 柴本银 史勇春 王宏耀 蒋斌 于 2019-10-09 设计创作，主要内容包括：本发明提供一种干燥装置和干燥方法,涉及农副产品加工领域。该干燥装置包括连续的多级干燥单元,每级干燥单元均包括干燥室和加热模块,加热模块用于使干燥室维持设定温度。在任意相邻两级干燥单元中,后一级干燥单元的加热模块产生的温度值低于前一级干燥单元的加热模块产生的温度值。该干燥方法包括：S1：在具有设定温度的干燥室内,对物料进行干燥；S2：将物料输送到温度更低的下一级干燥室,对物料进行干燥；S3：重复S2步骤。本发明缓解了现有技术中存在的热风干燥过程采用一个合适的干燥温度持续干燥果蔬,会在干燥后期导致果蔬本体升温较高,营养损失较多的技术问题。(The invention provides a drying device and a drying method, and relates to the field of agricultural and sideline product processing. The drying device comprises a plurality of continuous drying units, wherein each drying unit comprises a drying chamber and a heating module, and the heating module is used for maintaining the drying chamber at a set temperature. In any two adjacent drying units, the temperature value generated by the heating module of the next drying unit is lower than that generated by the heating module of the previous drying unit. The drying method comprises the following steps: s1: drying the material in a drying chamber with a set temperature; s2: conveying the material to a lower-temperature next-stage drying chamber, and drying the material; s3: the step of S2 is repeated. The invention solves the technical problems that the fruit and vegetable bodies are heated up relatively and the nutrition loss is relatively high in the later drying stage when the fruit and vegetable are continuously dried at a proper drying temperature in the hot air drying process in the prior art.)

1. Drying apparatus, characterized in that it comprises a succession of multi-stage drying units, each stage of said drying units comprising a drying chamber and a heating module for maintaining said drying chamber at a set temperature;

in any two adjacent stages of the drying units, the temperature value generated by the heating module of the drying unit at the next stage is lower than the temperature value generated by the heating module of the drying unit at the previous stage.

2. The drying apparatus of claim 1, wherein the drying unit further comprises a circulation fan and a duct;

the drying chamber is provided with an air inlet and an air outlet, and the air inlet, the pipeline and the air outlet are communicated in sequence;

the heating module and the circulating fan are both arranged on the pipeline, the heating module is used for heating the gas in the pipeline, and the circulating fan is used for enabling the gas to circularly flow in the drying chamber and the pipeline.

3. The drying apparatus according to claim 2, wherein the heating module in the drying unit located before the drying unit of the last stage is a heat exchanging apparatus, and the heating module in the drying unit of the last stage is a heat pump system.

4. The drying device according to any one of claims 1 to 3, further comprising a cooling unit, wherein the cooling unit comprises a cooling chamber and a cooling module, the cooling chamber is communicated with the drying chamber, and the cooling module is used for maintaining the cooling chamber at a set temperature.

5. The drying apparatus according to claim 4, further comprising a conveying mechanism, wherein an inlet end of the conveying mechanism is located outside the drying chamber in the first stage of the drying unit, and an outlet end of the conveying mechanism is located outside the cooling chamber after passing through the plurality of drying chambers and the cooling chamber in sequence.

6. The drying apparatus of claim 5, wherein the conveying mechanism comprises a conveyor belt, rollers, and a motor;

the feeding end and the discharging end of the conveying mechanism are both located on the conveying belt, the conveying belt is sleeved on the roller, the roller is connected with the motor, and the roller can be driven by the motor to rotate so as to drive the conveying belt to rotate.

7. A drying method, characterized in that the drying method comprises:

s1: drying the material in a drying chamber with a set temperature;

s2: conveying the material to a lower-temperature next-stage drying chamber, and drying the material;

s3: the step of S2 is repeated.

8. The drying method according to claim 7, wherein after the step of S2, the drying method further comprises:

s20: detecting whether the water content of the material is qualified or not, and if the water content of the material is qualified, conveying the material with qualified water content to a finished product area; and if the water content of the material is unqualified, performing S3 on the material with unqualified water content.

9. The drying method according to claim 7 or 8, wherein after the step of S3, the drying method further comprises:

s4: and conveying the material into a cooling chamber with a set temperature, and cooling the temperature of the material to room temperature.

10. The drying method according to claim 9, wherein before the step of S1, the drying method further comprises:

s0: the material is cut into a plurality of portions.

Technical Field

The invention relates to the technical field of agricultural and sideline product processing, in particular to a drying device and a drying method.

Background

Fruits and vegetables are rich in components necessary for human diet, such as saccharides, amino acids, vitamins, cellulose, trace elements, and the like. Fresh fruits and vegetables are not durable to store, and are easy to deteriorate or lose nutrition value with the passage of time. In order to prolong the shelf life of fresh fruit and vegetable and reduce the loss of nutrients, the method of drying fresh fruit and vegetable is commonly used.

The existing drying processing method mainly comprises two methods of freeze drying and hot air drying. Freeze drying is a drying method in which fruits and vegetables are first frozen to below freezing point to convert the water in the fruits and vegetables into ice, and then the ice is converted into water vapor under higher vacuum to be removed. The hot air drying is a drying method which takes hot air as a drying medium and carries out mass and heat transfer with fruits and vegetables in a natural or forced convection circulation mode so as to evaporate and remove water in the fruits and vegetables. The freeze-drying processing method is low in cost and low in working efficiency, so that the conventional drying processing method is hot air drying.

The hot air drying process requires attention to two key points: 1. the evaporation of water in the fruits and vegetables is accelerated, so that the water content in the fruits and vegetables reaches a target value as soon as possible; 2. in order to prevent the nutrition in the fruits and vegetables from being damaged due to overhigh temperature, the temperature rise of the fruit and vegetable body in the drying process needs to be controlled. In order to balance the product quality and the working efficiency in the existing hot air drying processing method, a proper drying temperature is generally selected for continuously drying fruits and vegetables by comprehensively considering the two key points, such as the temperature of about 60 ℃.

However, even if the drying temperature is a proper temperature, the drying temperature for evaporating water is still high, and after the water in the fruits and vegetables is evaporated in the later period of drying, the drying temperature still causes the body of the fruits and vegetables to be heated up, so that the nutrition loss is high.

Disclosure of Invention

The invention aims to provide a drying device and a drying method, which are used for solving the technical problems that in the prior art, the temperature of a fruit and vegetable body is relatively high and the nutrition loss is relatively high in the later drying stage when the fruit and vegetable is continuously dried at a proper drying temperature in a hot air drying process.

The drying device provided by the invention comprises continuous multi-stage drying units, wherein each stage of drying unit comprises a drying chamber and a heating module, and the heating module is used for maintaining the drying chamber at a set temperature;

in any two adjacent drying units, the temperature value generated by the heating module of the next drying unit is lower than that generated by the heating module of the previous drying unit.

Further, the drying unit also comprises a circulating fan and a pipeline;

the drying chamber is provided with an air inlet and an air outlet, and the air inlet, the pipeline and the air outlet are communicated in sequence;

the heating module and the circulating fan are both arranged on the pipeline, the heating module is used for heating gas in the pipeline, and the circulating fan is used for enabling the gas to circularly flow in the drying chamber and the pipeline.

Furthermore, the heating module in the drying unit before the last stage of drying unit is a heat exchange device, and the heating module in the last stage of drying unit is a heat pump system.

Further, drying device still includes cooling unit, and cooling unit includes cooling chamber and cooling module, and cooling chamber and drying chamber intercommunication, cooling module are used for making the cooling chamber maintain the temperature of settlement.

Furthermore, the drying device also comprises a conveying mechanism, the feeding end of the conveying mechanism is positioned outside the drying chamber in the first-stage drying unit, and the discharging end of the conveying mechanism is positioned outside the cooling chamber after sequentially passing through the plurality of drying chambers and the cooling chamber.

Further, the conveying mechanism comprises a conveying belt, a roller and a motor;

the feed end and the discharge end of the conveying mechanism are both located on the conveying belt, the conveying belt is sleeved on the roller, the roller is connected with the motor, and the roller can rotate under the driving of the motor to drive the conveying belt to rotate.

The drying method provided by the invention comprises the following steps:

s1: drying the material in a drying chamber with a set temperature;

s2: conveying the material to a lower-temperature next-stage drying chamber, and drying the material;

s3: the step of S2 is repeated.

Further, after the step of S2, the drying method further includes:

s20: detecting whether the water content of the material is qualified or not, and if the water content of the material is qualified, conveying the material with qualified water content to a finished product area; and if the water content of the material is unqualified, performing S3 on the material with unqualified water content.

Further, after the step of S3, the drying method further includes:

s4: and conveying the material into a cooling chamber with a set temperature, and cooling the temperature of the material to room temperature.

Further, before the step of S1, the drying method further includes:

s0: the material is cut into a plurality of portions.

The drying device and the drying method provided by the invention can produce the following beneficial effects:

the drying device provided by the invention comprises a plurality of continuous drying units, wherein each drying unit comprises a drying chamber and a heating module. When the materials with moisture are dried, such as fruits and vegetables, the fruits and vegetables can sequentially pass through the drying chambers of the drying units at all stages. In the drying process, the evaporation rate of the moisture in the material is not constant, the evaporation rate of the moisture is gradually increased and then kept constant, and in the later drying stage, the evaporation rate of the moisture is gradually reduced. According to the invention, the drying process is divided into an evaporation acceleration stage, an evaporation constant speed stage and an evaporation deceleration stage according to the evaporation rate of water in the material, and drying units at all stages are set corresponding to the three stages. The drying unit with the front stage number in the drying device corresponds to the evaporation acceleration stage and the evaporation constant speed stage, and the set temperature of the drying chamber in the drying unit is higher, so that the moisture in the evaporated material can be accelerated when the material passes through the drying chamber in the drying unit. Because the earlier stage of the drying process, the temperature difference between the material and the drying chamber is large, the heat transfer driving force is strong, and the drying speed is high. Simultaneously, dry earlier stage material moisture content higher, moisture evaporation can absorb a large amount of heat to the temperature rise range that can make the material body is not high, can prevent the nutrition loss in the material body. The drying unit with the later stage number in the drying device corresponds to the evaporation speed reduction stage. When the moisture in the material is largely evaporated by the drying unit with the front stage number, the high-temperature drying material is continuously utilized to cause the temperature of the material body to rise too high. The drying chamber in the drying unit with the later stage is lower in set temperature, so that the ambient temperature of the material with a large amount of evaporated moisture is reduced when the material enters the drying chamber in the drying unit with the later stage, the temperature of the material body is prevented from being increased too high, and meanwhile, the moisture in the material can be continuously evaporated.

Compared with the prior art that the fruits and vegetables are continuously dried at a proper drying temperature, the drying device provided by the invention can accelerate the evaporation of water in the fruits and vegetables by using the high temperature in the drying unit with the front stage number, so that the water content in the fruits and vegetables can reach a target value as soon as possible, and the nutrition in the materials can not be damaged. The drying device provided by the invention can also utilize the temperature lower than the high temperature in the drying unit with the later stage number to prevent the materials with a large amount of evaporated moisture from being continuously heated in time, and then the materials can be continuously dried while the nutrition in the materials is prevented from being damaged. The drying device provided by the invention is used for drying materials, so that the drying time can be shortened, the working efficiency is improved, the nutrient loss of the dried materials can be reduced, and the double improvement of the working efficiency and the quality of finished products is realized. In addition, when the drying device provided by the invention is used for drying materials, a plurality of batches of materials can sequentially pass through the drying chambers of the drying units at all stages. Therefore, the drying device provided by the invention can continuously dry a large amount of materials, further improve the working efficiency and improve the yield.

The principle of the drying method provided by the invention is the same as that of the drying device, the drying process is divided into an evaporation acceleration stage, an evaporation constant speed stage and an evaporation deceleration stage, and drying chambers of all stages are set corresponding to the three stages. The method provided by the invention also enables the material to pass through the drying chamber with high temperature and then enter the drying chamber with the temperature lower than the high temperature, so that the material is firstly dried at the high temperature and then dried at the temperature lower than the high temperature. The principle of the drying method provided by the invention is the same as that of the drying device, so that the drying method provided by the invention has the same beneficial effects as the drying device.

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, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a drying device according to a first embodiment of the present invention;

FIG. 2 is a flow chart of a drying method provided in the second embodiment of the present invention;

fig. 3 is another flow chart of the drying method provided in the second embodiment of the present invention.

Icon: 1-a drying unit; 10-a drying chamber; 11-heating module; 12-a circulating fan; 13-a pipeline; 2-a cooling unit; 20-a cooling chamber; 21-a cooling pipe; 3-a conveying mechanism.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.