Total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system

Abstract

The present invention provides a total heat recovery vacuum fresh-keeping heat pump drying and puffing embrittlement system, belonging to the technical field of food processing equipment, which includes a vacuum wheel group system, a vacuum pump group system, a cold trap system, and a heat energy recovery and temperature control circulation system; the vacuum wheel group system includes n parallel vacuum tanks, where n≥2. A main gas pipeline is provided on one side of the n vacuum tanks. A puffing tank is connected to the main gas pipeline, and the vacuum tanks are connected to the main gas pipeline through branch gas pipelines; the vacuum pump group system is used to achieve and maintain the vacuum degree of the vacuum tanks. The vacuum pump group system is connected to the main gas pipeline, and the cold trap system is connected between the vacuum pump group system and the main gas pipeline; the heat energy recovery and temperature control circulation system is used to recover the heat of the vacuum pump group system and the cold trap system, and the heat energy recovery and temperature control circulation system is used for heating and cooling the vacuum tanks; the present invention realizes total heat recovery, operates under vacuum, and dries and puffs at low temperature, and can achieve a high drying quality, and the drying process is green and environmentally friendly.

Description

Technical Field

[0001] The present invention relates to the technical field of food processing equipment, and particularly relates to a total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system. Background Art

[0002] Puffed food is a new type of food developed internationally in recent years. It uses grains, beans, potatoes, vegetables, etc. as raw materials, and through the processing of puffing equipment, a variety of puffed foods are manufactured, with delicate shapes, rich nutrition, crispy and delicious taste. Therefore, it uniquely forms a large category of food.

[0003] During the production process of puffed food, after the food is formed, it needs to be put into a drying device to remove part of the moisture for drying and shaping. Therefore, the drying efficiency directly determines the production efficiency of puffed food.

[0004] There are various food drying methods, such as high-temperature drying, freeze-drying, low-temperature drying, etc. High-temperature drying usually causes various physical and chemical changes in food, mainly including loss of nutrients, changes in flavor and shape, and browning. The main influencing factors are temperature and time. The higher the temperature and the longer the time, the more serious the damage to substances. Therefore, high-temperature drying is not suitable for heat-sensitive substances; freeze-drying can maintain the original color, aroma, taste and nutrition of substances, and the drying quality is the best, but the drying system has a complex structure, high initial investment in equipment, long drying time, and extremely high energy consumption, which limits its application.

[0005] Low-temperature drying is a process of using low-temperature and low-humidity air to circulate over food to gradually reduce its moisture content to achieve drying. Low-temperature drying causes little damage to heat-sensitive substances and has a relatively low cost, thus showing great development potential. Low-temperature drying uses air with extremely low moisture content and not high temperature as a carrier for material drying. During the drying process, the product temperature does not exceed 35°C. Therefore, it is suitable for drying heat-sensitive materials such as medicine and food. Low-temperature drying uses the vapor pressure difference between dry air and wet materials as the driving force. Therefore, the key technology is the acquisition of dry air.

[0006] At present, the existing puffed food drying equipment has some deficiencies due to the limitations of drying principles and structures: 1. The heat energy dissipated during the drying process is not convenient for recycling, resulting in a great waste of energy; 2. Since the food directly contacts the outside cold air during the drying process, the following problems occur: the drying time will change with the change of the outside temperature; the energy consumption changes with the change of the outside temperature, and the cost also increases rapidly; the temperature is very difficult to control within the required range. If the temperature is too low, the moisture content error of the food is large and cannot reach the required value. If it is too high, the food volume expands and there are burnt particles; contacting with air affects the freshness of the product and the processing effect; 3. It is not convenient to achieve large-scale food processing or continuous operation, and the processing efficiency needs to be improved. Summary of the Invention

[0007] In view of this, the present invention provides a total heat recovery vacuum fresh-keeping heat pump drying and puffing and embrittling system, which realizes total heat recovery, operates under vacuum, and performs low-temperature drying and puffing, can achieve a relatively high drying quality, and the drying process is green and environmentally friendly.

[0008] To solve the above technical problems, the present invention provides a total heat recovery vacuum fresh-keeping heat pump drying and puffing and embrittling system, including a vacuum wheel group system, a vacuum pump group system, a cold trap system, and a heat energy recovery and temperature control circulation system;

[0009] The vacuum wheel group system includes n parallel vacuum tanks, where n≥2. A main gas pipeline is provided on one side of the n vacuum tanks. An expansion tank is connected to the main gas pipeline, and the vacuum tanks are connected to the main gas pipeline through branch gas pipelines;

[0010] The vacuum pump group system is used to achieve and maintain the vacuum degree of the vacuum tanks. The vacuum pump group system is connected to the main gas pipeline, and the cold trap system is connected between the vacuum pump group system and the main gas pipeline;

[0011] The heat energy recovery and temperature control circulation system is used to recover the heat of the vacuum pump group system and the cold trap system, and is used for heating and cooling the vacuum tanks.

[0012] By adopting the above technical solution, it is possible to drive the operation of the vacuum wheel group system containing multiple groups of vacuum tanks, realize the continuous operation of the dried materials in the vacuum tanks, meet the requirement of quickly reaching the vacuum degree, and effectively improve the work efficiency.

[0013] Further, a first gas path valve is provided on the branch gas pipeline, a pressure relief valve is provided on the vacuum tank, and a pressure sensor is provided inside the vacuum tank.

[0014] Further, a temperature and humidity sensor is provided inside the vacuum tank, a water coil is provided inside the vacuum tank, and the water coil is connected to the heat energy recovery and temperature control circulation system in a circulating manner through an inlet pipe and an outlet pipe.

[0015] Further, the heat energy recovery and temperature control circulation system includes a high-temperature water tank and an intermediate water tank;

[0016] First water valves are provided on the pipelines where the inlet pipe and the outlet pipe are connected to the high-temperature water tank, and second water valves are provided on the pipelines where the inlet pipe and the outlet pipe are connected to the intermediate water tank;

[0017] A first circulation water pump is provided on the inlet pipe.

[0018] Further, the intermediate water tank is connected to the spray cooling tower in a circulating manner. Third water valves are provided on the drainage pipeline and the return water pipeline connecting the intermediate water tank and the spray cooling tower, and a second circulation pump is provided on the drainage pipeline.

[0019] Further, the high-temperature water tank is connected in a cycle with the high-temperature heat pump water heater unit. A high-temperature unit circulation pump is provided on the circulation pipeline between the high-temperature water tank and the high-temperature heat pump water heater unit. The high-temperature heat pump water heater unit is connected with the vacuum pump group system and the cold trap system through a heat recovery circulation pipeline.

[0020] By adopting the above technical solution, environmental drying is realized through vacuum, the freshness preservation degree during the material drying process is improved, and the drying treatment effect is improved. In addition, heating and cooling are realized in a circulating manner, ensuring the drying rate and avoiding the phenomenon of scorching.

[0021] On the one hand, the temperature inside the vacuum tank can be increased through high-temperature circulation to realize the drying of components. On the other hand, through low-temperature circulating water, embrittlement treatment can be realized through cooling.

[0022] Further, the vacuum pump group system includes a primary vacuum pump and a secondary vacuum pump connected in series in sequence. The secondary vacuum pump is connected with the heat recovery circulation pipeline. A second gas path valve is provided on the pipeline where the primary vacuum pump is connected with the cold trap system.

[0023] Further, the cold trap system includes a cold trap catcher and a cold trap refrigeration unit for circulating refrigeration to the cold trap catcher;

[0024] The main gas pipeline is connected with one side of the cold trap catcher. The primary vacuum pump is connected with one side at the bottom end of the cold trap catcher. A condensate drain pipe is provided at the bottom end of the cold trap catcher, and a drain valve is provided on the condensate drain pipe;

[0025] One side of the cold trap refrigeration unit is connected with the heat recovery circulation pipeline.

[0026] By adopting the above technical solution, a closed loop is integrally formed, the heat generated by the cold trap system and the vacuum pump group system is effectively recovered, and is used to heat the water in the high-temperature water tank, effectively improving the heat energy recovery and reducing the waste of energy.

[0027] Further, a third gas path valve is provided on the pipeline where the puffing tank is connected with the main gas pipeline, and a pressure valve is provided on the puffing tank.

[0028] The beneficial effects of the above technical solution of the present invention are as follows:

[0029] 1. The present invention can realize the operation of driving the vacuum wheel group system containing multiple vacuum tanks, realize the continuous operation of drying materials in the vacuum tank, can meet the requirement of quickly reaching the vacuum degree, and effectively improve the working efficiency.

[0030] 2. In the present invention, a closed loop is formed as a whole, and the heat generated by the cold trap system and the vacuum pump group system is effectively recovered and used to heat the water in the high-temperature water tank, effectively improving the heat energy recovery and reducing the waste of energy.

[0031] 3. In the present invention, diverse treatments such as material puffing, drying, and crisping can be realized, forming a relatively complete associated operation system, which is more convenient to use.

[0032] 4. In the present invention, environmental drying is achieved through vacuum, improving the freshness during the material drying process and enhancing the drying treatment effect. Additionally, heating and cooling are realized through a circulation method, ensuring the drying rate while avoiding the phenomenon of scorching;

[0033] On the one hand, the temperature inside the vacuum tank can be increased through high-temperature circulation to achieve component drying, and on the other hand, through low-temperature circulating water, crisping treatment can be achieved through cooling. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic diagram of the total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system of the present invention;

[0035] Figure 2 is a schematic diagram of the vacuum wheel group system in the present invention;

[0036] Figure 3 is a schematic diagram of the cold trap system in the present invention;

[0037] Figure 4 is a schematic diagram of the heat energy recovery and temperature control circulation system in the present invention.

[0038] 1. Vacuum wheel group system; 11. Vacuum tank; 111. Bronchial pipeline; 112. First air valve; 113. Pressure relief valve; 114. Pressure sensor; 115. Temperature and humidity sensor; 116. Water coil; 117. Water inlet pipe; 118. Water outlet pipe; 12. Main air pipeline; 13. Puffing tank; 131. Third air valve; 132. Pressurizing valve;

[0039] 2. Vacuum pump group system; 21. Primary vacuum pump; 22. Secondary vacuum pump; 23. Second air valve;

[0040] 3. Cold trap system; 31. Cold trap catcher; 32. Cold trap refrigeration unit;

[0041] 4. Heat energy recovery and temperature control circulation system; 41. High-temperature water tank; 411. First water valve; 42. Intermediate water tank; 421. Second water valve; 43. First circulation water pump; 44. Spray cooling tower; 441. Third water valve; 442. Second circulation pump; 45. High-temperature heat pump water heater unit; 451. High-temperature unit circulation pump; 452. Heat recovery circulation pipeline. Detailed Implementation Modes

[0042] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the following will describe the technical solutions of the embodiments of the present invention clearly and completely in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention fall within the scope of protection of the present invention. Figures 1-4

[0043] As Figures 1-4 shown: A total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system includes a vacuum wheel group system 1, a vacuum pump group system 2, a cold trap system 3, and a heat energy recovery and temperature control circulation system 4;

[0044] The vacuum wheel group system 1 includes 4 parallel-connected vacuum tanks 11. A main gas pipeline 12 is provided on one side of n vacuum tanks. A puffing tank 13 is connected to the main gas pipeline 12. The vacuum tank 11 is connected to the main gas pipeline 12 through a branch gas pipeline 111;

[0045] The vacuum pump group system 2 is used to achieve and maintain the vacuum degree of the vacuum tank 11. The vacuum pump group system 2 is connected to the main gas pipeline 12. The cold trap system 3 is connected between the vacuum pump group system 2 and the main gas pipeline 12;

[0046] The heat energy recovery and temperature control circulation system 4 is used to recover the heat of the vacuum pump group system 2 and the cold trap system 3, and the heat energy recovery and temperature control circulation system 4 is used for heating and cooling the vacuum tank 11.

[0047] Among them, a third gas path valve 131 is provided on the pipeline connecting the puffing tank 13 and the main gas pipeline 12, and a pressure increasing valve 132 is provided on the puffing tank 13.

[0048] Specifically, puffing treatment can be achieved through the puffing tank 13.

[0049] The whole forms a closed loop. The heat generated by the cold trap system and the vacuum pump group system is effectively recovered and used to heat the water in the high-temperature water tank, effectively improving the heat energy recovery and reducing the waste of energy.

[0050] Among them, a first gas path valve 112 is provided on the branch gas pipeline 111, a pressure relief valve 113 is provided on the vacuum tank 11, and a pressure sensor 114 is provided inside the vacuum tank 11.

[0051] Among them, a temperature and humidity sensor 115 is provided inside the vacuum tank 11, a water coil pipe 116 is provided inside the vacuum tank 11, and the water coil pipe 116 is connected to the heat energy recovery and temperature control circulation system 4 in a circulating manner through a water inlet pipe 117 and a water outlet pipe 118. ​

[0052] Among them, the heat energy recovery and temperature control circulation system 4 includes a high-temperature water tank 41 and an intermediate water tank 42;

[0053] On the pipelines where the water inlet pipe 117 and the water outlet pipe 118 are connected to the high-temperature water tank 41, first water valves 411 are provided, and on the pipelines where the water inlet pipe 117 and the water outlet pipe 118 are connected to the intermediate water tank 42, second water valves 421 are provided;

[0054] A first circulation water pump 43 is provided on the water inlet pipe 117.

[0055] Among them, the intermediate water tank 42 is externally connected to the spray cooling tower 44 in a circulating manner. Third water valves 441 are provided on both the drainage pipeline and the return water pipeline connecting the intermediate water tank 42 and the spray cooling tower 44, and a second circulation pump 442 is provided on the drainage pipeline.

[0056] Among them, the high-temperature water tank 41 is connected to the high-temperature heat pump water heater 45 in a circulating manner, and a high-temperature unit circulation pump 451 is provided on the circulation pipeline between the high-temperature water tank 41 and the high-temperature heat pump water heater 45.

[0057] Environmental drying is achieved through vacuum, improving the freshness during the material drying process and the drying treatment effect. In addition, heating and cooling are achieved through a circulating method, ensuring the drying rate while avoiding the phenomenon of charring.

[0058] On the one hand, it can achieve an increase in the temperature inside the vacuum tank 11 through high-temperature circulation to realize component drying, and on the other hand, it can achieve embrittlement treatment through low-temperature circulating water for cooling.

[0059] In another embodiment of the present invention, as Figure 1 shown,

[0060] The high-temperature heat pump water heater 45 is connected to the vacuum pump group system 2 and the cold trap system 3 through a heat recovery circulation pipeline 452.

[0061] Among them, the vacuum pump group system 2 includes a primary vacuum pump 21 and a secondary vacuum pump 22 connected in series in sequence. The secondary vacuum pump 22 is connected to the heat recovery circulation pipeline 452, and a second gas path valve 23 is provided on the pipeline where the primary vacuum pump 21 is connected to the cold trap system 3.

[0062] Among them, the cold trap system 3 includes a cold trap catcher 31 and a cold trap refrigeration unit 32 for circulating refrigeration of the cold trap catcher 31;

[0063] The main gas pipeline 12 is connected to one side of the cold trap catcher 31, the primary vacuum pump 21 is connected to one side of the bottom end of the cold trap catcher 31, a condensate drain pipe is provided at the bottom end of the cold trap catcher 31, and a drain valve is provided on the condensate drain pipe.

[0064] One side of the cold trap refrigeration unit 32 is communicated with the heat recovery circulation pipeline 452.

[0065] The whole forms a closed loop, and the heat generated by the cold trap system and the vacuum pump group system is effectively recovered and used to heat the water in the high-temperature water tank, effectively improving the heat energy recovery and reducing the waste of energy.

[0066] The working method of the present invention: When specifically realizing vacuum fresh-keeping drying, materials are added into the vacuum tank 11 one by one. As Figure 1 shown, the four vacuum tanks 11 are numbered as the first vacuum tank, the second vacuum tank, the third vacuum tank, and the fourth vacuum tank from top to bottom in sequence; then the second air path valve 23 in the vacuum pump group system 2 and the first air path valve 112 on the upper bronchial pipeline 111 of the first vacuum tank are opened, and the primary vacuum pump 21 and the secondary vacuum pump 22 start to work. After the first vacuum tank reaches the vacuum degree, the first air path valve 112 on the upper bronchial pipeline 111 of the second vacuum tank is opened, and the vacuum pumping link is entered, and the treatment is carried out alternately in sequence; after the first vacuum tank reaches the target vacuum time, it is depressurized through the pressure relief valve 113 on it, and the pressure relief time is entered, and then the vacuum pumping treatment is entered again. The second, third, and fourth vacuum tanks are also depressurized and vacuum pumped alternately in sequence.

[0067] Meanwhile, the first water valve 411 on the pipeline connecting the water inlet pipe 117 and the water outlet pipe 118 with the high-temperature water tank 41 is opened to realize heating the inside of the vacuum tank 11 through the hot circulating water. During the vacuum pumping process, the extracted humid hot air passes through the cold trap catcher 31, and the moisture in the extracted air condenses into water in the cold trap catcher 31 and is discharged through the condensate drain pipe. Among them, the cold trap refrigeration unit 32 cools the cold trap catcher 31 through the refrigerant cycle with the cold trap catcher 31, and the refrigerant returns to the cold trap refrigeration unit 32 after absorbing heat, and the heat is recovered to the high-temperature heat pump water heater 45, and the high-temperature heat pump water heater 45 is used to heat the high-temperature water tank. Similarly, the heat generated by the vacuum pump group system 2 is also recovered to the high-temperature heat pump water heater 45.

[0068] When the materials need to be embrittled, after the drying and pressure relief treatment of the materials in the vacuum tank 11 is completed, the air path valve is closed, and at the same time, the first water valve 411 communicating with the high-temperature water tank 41 is closed, and at the same time, the second water valve 421 on the pipeline connecting with the intermediate water tank 42 is opened to realize circulating the low-temperature cold water in the intermediate water tank 42 into the vacuum tank 11 to realize the embrittlement treatment. After the circulating water in the intermediate water tank 42 becomes warmer during the temperature reduction process, it can be circulated and connected with the spray cooling tower 44 to realize cooling the water in the intermediate water tank 42.

[0069] When the material needs to be puffed, put the material to be puffed into the puffing tank 13, inject high-pressure nitrogen through the pressure valve 132 to maintain pressure for a certain period of time. After all the vacuum tanks 11 reach the target vacuum degree, quickly open the third gas path valve 131 and maintain it for a certain period of time, then close the third gas path valve 131. After depressurization, it is done.

[0070] This technical solution realizes total heat recovery, avoids energy waste, operates under vacuum, and dries and puffs at low temperature, effectively improving the freshness during the drying process, optimizing the drying effect, achieving a relatively high drying quality, with a green and environmentally friendly drying process, continuous operation during the drying process, and improving processing efficiency.

[0071] It can realize diversified treatments such as material puffing, drying, and crisping, forming a relatively complete associated operation system, which is more convenient to use.

[0072] In the present invention, unless otherwise clearly specified and limited, for example, it can be fixedly connected, detachably connected, or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components or the interaction relationship between two components. Unless otherwise clearly defined, for those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0073] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle described in the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system, characterized in that: It includes a vacuum wheel set system (1), a vacuum pump set system (2), a cold trap system (3), and a heat recovery and temperature control circulation system (4); The vacuum wheel set system (1) includes n parallel vacuum tanks (11), where n≥2. A main gas pipeline (12) is provided on one side of the n vacuum tanks (11). An expansion tank (13) is connected to the main gas pipeline (12). The vacuum tank (11) is connected to the main gas pipeline (12) through a branch gas pipeline (111); A water coil (116) is provided in the vacuum tank (11), and the water coil (116) is connected to the heat recovery and temperature control circulation system (4) in a circulating manner through a water inlet pipe (117) and a water outlet pipe (118); The vacuum pump set system (2) is used to achieve and maintain the vacuum degree of the vacuum tank (11). The vacuum pump set system (2) is connected to the main gas pipeline (12), and the cold trap system (3) is connected between the vacuum pump set system (2) and the main gas pipeline (12); The heat recovery and temperature control circulation system (4) is used to recover the heat of the vacuum pump set system (2) and the cold trap system (3), and the heat recovery and temperature control circulation system (4) is used for heating and cooling the vacuum tank (11); The heat recovery and temperature control circulation system (4) includes a high-temperature water tank (41) and an intermediate water tank (42); First water valves (411) are provided on the pipelines where the water inlet pipe (117) and the water outlet pipe (118) are connected to the high-temperature water tank (41). Second water valves (421) are provided on the pipelines where the water inlet pipe (117) and the water outlet pipe (118) are connected to the intermediate water tank (42); A first circulation pump (43) is provided on the water inlet pipe (117); The intermediate water tank (42) is connected to the spray cooling tower (44) in a circulating manner externally. Third water valves (441) are provided on the drainage pipeline and the return water pipeline connected between the intermediate water tank (42) and the spray cooling tower (44). A second circulation pump (442) is provided on the drainage pipeline; The high-temperature water tank (41) is connected to the high-temperature heat pump water heater (45) in a circulating manner. A high-temperature unit circulation pump (451) is provided on the circulation pipeline between the high-temperature water tank (41) and the high-temperature heat pump water heater (45). The high-temperature heat pump water heater (45) is connected to the vacuum pump set system (2) and the cold trap system (3) through a heat recovery circulation pipeline (452).

2. The total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system according to claim 1, characterized in that: A first gas path valve (112) is provided on the branch gas pipeline (111). A pressure relief valve (113) is provided on the vacuum tank (11). A pressure sensor (114) is provided in the vacuum tank (11).

3. The total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system according to claim 2, wherein: A temperature and humidity sensor (115) is provided in the vacuum tank (11).

4. The total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system according to claim 1, wherein: The vacuum pump set system (2) includes a primary vacuum pump (21) and a secondary vacuum pump (22) connected in series in sequence. The secondary vacuum pump (22) is connected to the heat recovery circulation pipeline (452). A second gas path valve (23) is provided on the pipeline where the primary vacuum pump (21) is connected to the cold trap system (3).

5. The total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system according to claim 4, characterized in that: The cold trap system (3) includes a cold trap collector (31) and a cold trap refrigeration unit (32) for circulating refrigeration to the cold trap collector (31); The main gas pipeline (12) is communicated with one side of the cold trap collector (31), the primary vacuum pump (21) is communicated with one side of the bottom end of the cold trap collector (31), a condensate drain pipe is arranged at the bottom end of the cold trap collector (31), and a drain valve is arranged on the condensate drain pipe; One side of the cold trap refrigeration unit (32) is communicated with the heat recovery circulation pipeline (452).

6. The total heat recovery vacuum fresh-keeping heat pump drying and puffing and crisping system according to claim 1, characterized in that: A third gas path valve (131) is arranged on the pipeline communicating the puffing tank (13) and the main gas pipeline (12), and a pressurizing valve (132) is arranged on the puffing tank (13).

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