Tea leaf electric baking equipment and baking method capable of performing composite heat transfer by combining convection heating and radiation wall

Abstract

According to the technical scheme, the invention discloses a tea leaf electric baking device and baking method combining convection heating and a radiation wall for composite heat transfer. The invention relates to tea leaf electric baking equipment for composite heat transfer by combining convection heating and a radiation wall. The tea leaf electric baking equipment comprises a box body, a multi-layer bracket rotating bracket, a forced convection heating mechanism, a thermal radiation electric heating mechanism and an electric control mechanism, according to the technical scheme, electric power serves as energy, a traditional charcoal baking firepower baking technology is replaced, large-scale, precise and high-quality material baking is achieved, and meanwhile the problems that existing equipment is large in occupied area, complex in operation and unstable in batch quality are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tea processing equipment, in particular to an electric baking equipment for composite heat transfer by combining convection heating and radiation wall, which can also be applied to drying and aroma extraction process in processing of materials such as agaric and shiitake mushrooms, and is especially suitable for large-scale processing of tea categories such as green tea and Wuyi rock tea with high requirements for baking quality. BACKGROUND

[0002] In the processing flow of materials such as tea, agaric, shiitake mushrooms, and Chinese herbal medicines, drying and aroma extraction are key process links that determine product quality. Taking tea processing as an example, the formation and retention of aroma substances directly affect the flavor and market value of tea, and the aroma sources mainly include free-state aroma substances contained in fresh leaves, aroma substances generated by physical and chemical changes or enzymatic reactions under heat during processing, and adsorption of exogenous aroma by tea leaves, among which heat reaction during processing is the core approach to the generation of aroma substances.

[0003] In the prior art, the tea baking equipment mainly has the following deficiencies: 1. Limitation of single heating mode: The existing equipment only uses forced air convection heating, which cannot meet the differentiated needs of different processing stages of tea for heat transfer modes, and is prone to cause process problems such as loss of aroma substances or “water retention”; in addition, although other existing equipment realizes switching between hot air and radiation, manual intervention is required to switch the process, and the two heat transfer modes cannot be cooperatively controlled, making it difficult to accurately match the complex reaction process of tea aroma formation.

[0004] 2. Defects of traditional charcoal baking technology: Traditional handmade tea relies on charcoal baking cages, which have problems such as low single-cage yield, dependence on experience for charcoal fire control, and large differences in quality between batches. Although the number of charcoal baking cages has been increased to improve yield, a wide workshop space (large floor area) is required, and the combustion processes of multiple charcoal fires are difficult to control synchronously, so there are still significant differences in the quality of tea in the same batch.

[0005] 3. Insufficient parameter regulation accuracy: The existing equipment lacks systematic control over key parameters during the baking process, such as real-time monitoring and accurate adjustment of parameters such as air flow, radiation temperature, and material temperature, which cannot meet the process requirements of “drying method, temperature, time, and moisture content directly affecting the conversion of tea contents” proposed in “Research Progress on the Formation of Green Tea Nutmeg and Its Process” (Chinese Agricultural Bulletin, 2020, 36(2)), and it is difficult to stably generate high-quality aroma substances. SUMMARY

[0006] In view of the deficiencies of the prior art, the tea electric baking equipment for composite heat transfer combining convection heating and radiation wall is provided, which uses electricity as energy source, replaces the traditional charcoal baking technology, realizes the scaling, precision and high quality of material baking, and solves the problems of large equipment area, complex operation and unstable batch quality.

[0007] The application also relates to a tea electric baking method using the above-mentioned tea electric baking equipment.

[0008] The tea electric baking equipment for composite heat transfer combining convection heating and radiation wall comprises the following components. The box body is provided with a sealing door, and a closed space is formed in the sealing door, which is only communicated with the outside through the flow inlet and the flow outlet, so that the baking environment is stable; the sealing door facilitates the loading and unloading of materials; and the multi-layered bracket rotating support is used for placing the drying box body containing materials, is driven by a motor to rotate around the rotating support rotating shaft in the vertical direction, and ensures that the materials on each layer of the bracket uniformly receive radiation heating and convection heating. The forced convection heating mechanism comprises a fan, a duct electric heating element and a duct structure; the fan is installed on the duct of the box body, the duct is communicated with the outside through the flow inlet and the flow outlet, and passes through the multi-layered bracket rotating support in the box body, so that the hot air and the materials are in full contact; a baffle is arranged in the duct to prevent air flow short circuit; and a one-way air valve is arranged on the baffle, so that when the flow inlet and the flow outlet are closed, the air in the duct is forced to circulate, and the air temperature is rapidly increased. The heat radiation electric heating mechanism has a heating ceramic plate, the heating ceramic plate is vertically arranged between the multi-layered bracket rotating support and the box body, and the materials are ensured to receive radiation heating in all directions. The electric control mechanism comprises a temperature control system and a touch display screen; the temperature control system realizes real-time monitoring and automatic control of the air temperature in the duct, the temperature of the radiation wall and the temperature of the materials; and the touch display screen supports target parameter combination setting and real-time parameter combination and performance parameter combination display, and is convenient to operate.

[0009] The electric control mechanism establishes three parameter systems of real-time parameter combination, target parameter combination and performance parameter combination, realizes precise control of the baking process, and specifically as follows. a. Real-time parameter combination: reflecting the current running state of the equipment, comprising: Fluid parameters: real-time controllable flow outlet area / flow rate and real-time controllable flow inlet area / flow rate; Temperature and power parameters: real-time air temperature in the duct, real-time electric heating power of the duct, real-time radiation temperature / power of the heating ceramic plate and real-time material temperature; b. Target parameter combination: set by the user according to the characteristics of the materials, comprising: Fluid parameters: target controllable flow outlet area / flow rate, target controllable flow inlet area / flow rate Temperature and power parameters: target air duct air temperature / electric heating power, target heat-emitting ceramic plate radiation temperature / power, target material temperature Process parameters: target air duct air temperature rise process controllable point temperature quantity and adjacent controllable point temperature time used, i.e. support segmented setting c. Performance parameter combination: reflecting device operation capacity, including: Fluid performance: slowest / fastest air duct conveying flow (volume) Power performance: maximum air duct electric heating element electric heating power, maximum heat-emitting ceramic plate radiation electric heating power Regulation performance: maximum air duct air temperature rise process controllable point temperature quantity

[0010] The airing box body is made of stainless steel wire mesh, facilitating radiation penetration and air circulation.

[0011] The heat-emitting ceramic plate has a size not less than the parallel projection of the multi-layer bracket rotating support on the plate surface, and the plate surface is flat.

[0012] The real-time controllable flow outlet area and the target controllable flow outlet area are the total area of the small holes of the air outlet plate array, and the real-time controllable flow inlet area and the target controllable flow inlet area are the total area of the small holes of the air inlet plate array, which are adjusted by replacing air outlet plates / air inlet plates with different small hole densities.

[0013] A tea electric baking method combining convection heating and radiation wall for composite heat transfer, comprising the following steps: a. Material preparation: placing the tea to be baked into a stainless steel wire mesh airing box body, controlling the material stacking thickness, placing the box body layer by layer on a multi-layer bracket rotating support, and closing the sealing door b. Parameter setting: the user sets the following parameters through the touch display screen: Segmented process parameters: dividing the air duct air temperature rise process into a first stage of baking, i.e. rapid heating, a second stage of aroma enhancement, i.e. constant temperature and aroma preservation, and a third stage of cooling, i.e. temperature reduction to normal temperature, and setting the target temperature and duration of each stage Radiation and convection parameters: target heat-emitting ceramic plate radiation temperature / power, target flow inlet / flow outlet flow rate Material parameters: target material temperature, used for linkage control of radiation and convection power c. Start operation: After cold start, the fan is started, fresh air from the outside enters the air duct through the automatic adjustment air valve of the air inlet, is heated by the air duct electric heating element, and then flows to the multi-layer bracket rotating support through the air inlet cavity, the air inlet plate small hole, and exchanges heat with the material Radiation wall synchronous start, release infrared radiation to the material, multi-layer bracket rotating support rotation to ensure uniform heating of the material; The air after heat exchange enters the exhaust cavity through the small holes of the air outlet plate, and is discharged to the outside through the exhaust port flow valve. When the inlet / exhaust port is closed, the one-way air valve is opened, and the air circulates in the air duct for heating; d. Real-time control: The temperature control system monitors various parameters in real time. When there is a deviation between the real-time parameter combination and the target parameter combination, the air duct electric heating power, the radiation wall power, or the air valve opening degree is automatically adjusted to ensure process stability; e. End of material taking: After the equipment runs to the end of the third stage, it automatically stops, opens the sealing door, takes out the drying box, and completes the green tea baking.

[0014] The outlet flow rate is automatically adjusted by adjusting the air inlet automatic adjusting valve and the exhaust port flow valve.

[0015] The touch display screen sets the target air duct air temperature rise process controllable point temperature and the time used by the adjacent target air duct air temperature rise process controllable point temperature; sets the target heating ceramic plate radiation temperature or the target radiation electric power; sets the flow valve flow or the automatic adjusting valve flow; the touch display screen displays the real-time material temperature and the real-time air duct air temperature.

[0016] The target air duct air temperature rise process controllable point temperature and the time used by the adjacent target air duct air temperature rise process controllable point temperature are divided into three stages: the first stage of baking, the second stage of aroma enhancement, and the third stage of cooling.

[0017] The present case has the following advantages: 1. The existing box-type forced convection heating electric baking equipment is modified into an electric baking equipment that simulates the natural process of traditional charcoal baking firepower baking. The characteristics of large capacity and rotation of the multi-layer bracket rotating support loaded with materials are ingeniously used. The radiation wall is installed on the side of the multi-layer bracket rotating support, so that the materials on each bracket can equally receive radiation from the radiation wall. This solves the problem of needing many charcoal baking cages to achieve large material quantity baking.

[0018] 2. Compared with the horizontal and upward radiation of the radiation surface of the charcoal baking furnace, the radiation surface of the present case is in the vertical direction, and the radiation direction is horizontal. The materials are layered and stacked on the multi-layer bracket rotating support, which can be extended upward to add materials. This solves the problem of expanding the land area to achieve large material quantity for multiple charcoal baking cages placed on the ground, and achieves small land area per unit weight of material.

[0019] 3. The charcoal roasting furnace has difficulty in controlling the fire power during the charcoal combustion process. The present application uses commercial or industrial electricity to achieve stable voltage and stable fire power. This is beneficial for users to control the fire power, accumulate experience in making tea, and achieve rapid progress in exploring the production process.

[0020] 4. A parameter system is proposed, including real-time parameter combination, target parameter combination, and performance parameter combination, which has a wide range of depth and a wide range of depth. Users can use the device to roast materials, and the device can be operated in multiple states by selecting parameter combinations. This provides powerful support for current people exploring radiation heating and convection heating to roast various materials. At the same time, it also lays the foundation for subsequent improvement of the device and opens up an effective direction for effort. The parameter system covers key indicators such as fluid, temperature, and power, supports segmented process setting, and can adapt to the roasting needs of different materials such as green tea, Wuyi rock tea, agaric, and shiitake mushrooms, and provides device support for aroma formation mechanism research.

[0021] 5. The temperature of the controllable point of the air temperature rise process of each target air duct and the time used for the temperature of the controllable point of the air temperature rise process of the adjacent target air duct are divided into three stages: the first stage is roasting, the second stage is aroma extraction, and the third stage is cooling. A three-stage roasting process is adopted, which is simple and convenient to operate. Combined with touch screen operation, users can start without professional roasting experience. Compared with traditional charcoal roasting experience that requires 3-5 years of experience accumulation, the training period of the operator is shortened to 1-2 weeks. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is the front view of the present application; Figure 2 is the right view of the present application; Figure 3 is the left view of the present application; Figure 4 is the cross-sectional view of the present application Figure 5 is Figure 4 A-A cross-sectional view of the present application; Figure 6 is Figure 4 B-B cross-sectional view of the present application; Figure 7 is Figure 4 C-C cross-sectional view of the present application; 1. Motor, 2. Box, 3. Sealing door, 4. Electric control mechanism, 5. Fan, 6. Air outlet plate, 7. Multi-layer bracket rotating support, 8. Exhaust cavity, 9. Radiant wall, 10. Rotating support shaft, 11. Partition, 12. Air duct heating element, 13. Air inlet plate, 14. Air inlet cavity, 15. Outlet, 16. Inlet. DETAILED DESCRIPTION

[0023] Please refer to Figures 1 to 7, the electric baking equipment of one kind of composite heat transfer of convection heating combined with the radiation wall 9 in the figure, mainly designs the box 2, the multi-layer bracket rotating support 7, the forced convection heating mechanism, the thermal radiation electric heating mechanism, the electric control mechanism 4; through the configuration of the above components, the equipment can realize the material baking of large scale, precision and high quality, and solve the problems of large floor area, complex operation and unstable batch quality of existing equipment.

[0024] The box 2 in the figure has a sealing door 3 which is opened and closed, and the whole is a frame structure with an internal cavity, the shell has a heat preservation layer structure, and the shell top has an air inlet 16 and an air outlet 15.

[0025] The multi-layer bracket rotating support 7 in the figure is used to place materials, the materials are spread in the flat-bottomed shallow edge drying box 2, and the drying box 2 containing materials is placed on each layer of the multi-layer bracket rotating support 7. The drying box 2 is made of stainless steel wire mesh, which facilitates the radiation energy of the radiation wall 9 from the thermal radiation electric heating mechanism to irradiate the materials in the box 2 or facilitates the air in the air duct in the box 2 to pass through the gaps between the materials in the box 2 and exchange heat with the materials. The sealing door 3 is opened, and the operator enters the box 2 to put the materials on the shelf or takes the baked materials off the shelf. The sealing door 3 is closed, and the air in the box 2 is sealed in the box 2, so the box 2 forms a closed box 2 with the air inlet 16 and the air outlet 15. The multi-layer bracket rotating support 7 is driven by the motor 1 to rotate around the rotating support shaft 10; the rotating support shaft 10 is fixedly assembled with the output shaft of the motor 1, and the rotating support shaft 10 is perpendicular to the horizontal plane in the vertical plane.

[0026] The forced convection heating mechanism in the figure has a fan 5 and an air duct electric heating element 12 for heating the air in the air duct; the fan 5 is installed on the air duct of the box 2, and the air duct is communicated with the outside through the air inlet 16 and the air outlet 15, and the air duct passes through the multi-layer bracket rotating support 7 in the box 2, and the air inlet 16 and the air outlet 15 are isolated by the partition plate 11 in the box 2 to prevent air flow short circuit.

[0027] The core of the thermal radiation electric heating mechanism in the figure is to convert electric energy into infrared radiation energy to directly heat the materials, which has the characteristics of high efficiency and uniform heating. The case adopts the design of radiation wall 9, that is, multiple radiation heating components are installed longitudinally to form a structure similar to a wall. The thermal radiation electric heating mechanism used in the case can use existing thermal radiation electric heating mechanisms, such as ceramic infrared radiation heating devices, milky white quartz tube heating devices, carbon fiber quartz electric heating tubes, high-frequency infrared radiators, nano infrared electric heating rings or plates, resistance radiation electric heaters, and graphene far infrared electric heaters.

[0028] Specifically, when the ceramic infrared radiation heating device is used, it is composed of a plurality of heating ceramic plates and is erected in the box 2 in alternation with the multi-layered tray rotating support 7. The heating ceramic plate is not less than the parallel projection of the multi-layered tray rotating support 7 on the plate surface in size, and the plate surface is flat. The radiation wall 9 refers to the radiation surface being wide enough and close enough to the material so that the heat radiation is directly irradiated on the material and the air around the material, reducing the attenuation of the heat radiation caused by the space distance. When the radiation wall 9 is made, the electrodes of the heating ceramic plates with small plate surface area of the same specification are connected in parallel to each other, so that each plate is combined into a large-area heating ceramic plate with an area meeting the above requirements. The flat plate surface of the heating ceramic plate refers to the plate surface being flat in macroscopic view, but rough in microscopic view or magnified view. These rough surfaces are used to enhance the radiation and improve the radiation rate.

[0029] The radiation wall 9 simulates the heat radiation of the charcoal oven in the charcoal baking. The charcoal oven directly radiates to the material on one hand, and heats the air in the cage on the other hand, so that the hot air in the cage flows to the material to directly contact with the material and transfer heat to the material. After causing the temperature of the material to rise, the flowing hot air also loses heat and its temperature decreases. Because the air inside and outside the charcoal baking cage is completely connected and flows freely, the hot air in the cage continues to flow and passes through the numerous small holes on the cage wall to reach the outside after completing the heat exchange with the material. At the same time, the cold air outside the cage will pass through the numerous small holes on the cage wall to supplement into the cage in time due to the negative pressure in the cage and reach above the charcoal oven to be heated. The hot air after being heated flows to the material and repeats the above process to transfer heat to the material and then moves away from the charcoal baking cage to reach the outside. Corresponding to the role of heat radiation in the charcoal baking, the heat radiation to the material in the present case is completed by the radiation of the radiation wall 9 and the rotation of the multi-layered tray rotating support 7. The convection of the hot air around the material is simulated by the forced convection heating mechanism in the present case. The air heated by the air duct heating element 12 and the air heated by the radiation wall 9 are all forced to be transported in the air duct by the fan 5. The hot air after the heat exchange with the material leaves the material and is finally discharged to the outside of the box 2. In the charcoal baking, the hot air is entirely heated by the radiation of the charcoal oven, while in the present case, the air duct heating element 12 heats the air, the radiation wall 9 is as close to the material as possible, and the load of the air heated by the radiation wall 9 is reduced, which increases the intensity of the radiation directly radiated to the material by the radiation wall 9. Through the intensity adjustment, the control of the microcosmic reaction process in the material caused by the radiation energy irradiation is strengthened.

[0030] The electric control mechanism 4 in the figure includes a temperature control system and a touch display screen. Among them, the temperature control system completes the task of controlling the temperature stability, when the real-time temperature is lower than the target temperature threshold, the temperature control system turns on the power supply of the heating device, and selects the appropriate heating power according to the time allowed to turn on the power supply to supplement the heat to the monitored object, and increase the temperature of the monitored object, until the time of turning on the power supply is used up, the optimization of the temperature control system in the case is mainly in the parameter combination set for it.

[0031] The touch display screen of the human-computer interaction interface is needed for display, and the finger touch is input by the operator, which can adopt the existing configuration. The touch display screen sets the temperature of the controllable point of the air temperature rise process of each target air duct and the time used by the temperature of the controllable point of the air temperature rise process of the adjacent target air duct; set the target heating ceramic plate radiation temperature or the target radiation electric power; the touch display screen displays the real-time material temperature, the real-time air temperature of the air duct. Real-time material temperature, real-time heating ceramic plate radiation temperature, real-time air temperature of air duct, real-time controllable flow outlet 15 area and real-time controllable flow inlet 16 area, these parameters are displayed on the touch display screen, the user can simply understand the current running condition of the electric baking equipment in the case. And the target controllable flow outlet 15 area, the target controllable flow inlet 16 area; the temperature of the controllable point of each target air duct air temperature rise process; the time used by the temperature of the controllable point of the air temperature rise process of the adjacent target air duct; the target heating ceramic plate radiation temperature or the target radiation electric power; the target material temperature These parameters are set by the user himself, so that the user himself decides the electric baking equipment in the case to run the baking material in what working condition. Those target parameters in the foregoing target parameter combination which are not set by the user on the touch display screen can be calculated according to the relevant theory or empirical formula by the target parameter combination value set by the user on the touch display screen, and the engineers can store this calculation method and the target parameter combination obtained by the calculation method in the temperature control system, and the temperature control system executes.

[0032] The electric control mechanism 4 in the case establishes three parameter systems of real-time parameter combination, target parameter combination and performance parameter combination to construct the necessary parameters of the simulation carbon baking roasting process of the case, and realizes the precise control of the baking process. Among them, the real-time parameter combination is the state parameter of the actual operation of the electric control system in the case at the current time. The target parameter combination is the state parameter that the user, that is, the operator, expects the electric control system in the case to reach in the future time, and when the time reaches the future time, the deviation of each target parameter combination from the corresponding real-time parameter combination is 0 deviation in normal circumstances, that is, no deviation. The target parameter combination enables the user to conveniently adopt the latest research results explored by predecessors for specific materials. The performance parameter combination is the running performance of the case to reach the state described by the target parameter combination, reflecting the execution ability of each execution element of the case and the anti-interference ability of the whole case. The performance parameter combination reflects the running ability of the equipment.

[0033] Specifically, the real-time parameter combination has the combination of the real-time controllable flow inlet 16 / flow outlet 15 area and the real-time controllable flow inlet 16 / flow outlet 15 flow rate, the real-time air duct air temperature and the real-time air duct electric heating power, the real-time heating ceramic plate radiation temperature and the real-time heating ceramic plate radiation power, and the real-time material temperature.

[0034] The real-time controllable flow inlet 16 / flow outlet 15 area and the real-time controllable flow inlet 16 / flow outlet 15 flow rate are described and expressed as follows: The air flowing into the cage is heated and then moves to the material surface, contacts the material surface, and then leaves the material surface, and finally passes through the cage wall to the outside. Obviously, the sum of all the surface areas of the material exposed to the air is an important heat exchange physical quantity. It represents the area of the material that contacts the hot air and absorbs the heat carried by the hot air during contact. The material roasted in the cage, such as tea leaves, is a stack of a certain number of granular materials, and each granule is curled, needle-shaped, spherical or flat due to previous processing. During roasting, hot air passes through the gaps inside the material stack, and only the surface exposed to hot air has the opportunity to contact hot air and exchange heat with hot air. The total area of all these surfaces needs to be manually intervened during roasting. The conventional operation is to shake and turn, thereby changing the posture of each granule in the material stack and changing the surface area that contacts the hot air. The purpose of shaking and turning is to give each granule an equal opportunity to be heated, so that the same batch of material has the same quality.

[0035] Corresponding to the total area of these surfaces, the box-type roasting of the present case uses the area of the air flowing into the multi-layer tray rotating support 7 and the area of the air flowing out of the multi-layer tray rotating support 7 as parameters, which can explain from another aspect where the hot air participates in heat exchange. This is because the heat absorbed by the material granules on the surface area that contacts the hot air is equal to the heat released by the hot air. The actual amount of hot air flowing in through the flow inlet 16 (area) and flowing out through the flow outlet 15 (area) is indicated by the controllable flow inlet 16 flow rate and the controllable flow outlet 15 flow rate of the air passing through the flow inlet 16 and the flow outlet 15, respectively. With the two parameters of area and flow rate, their product is the flow. How much hot air participates in heat release over how long a period of time can be accurately calculated in theory, thereby achieving accurate control of the amount of air flowing in and out, and finally achieving the purpose of accurately controlling the material temperature and the micro-reaction process inside the material during roasting.

[0036] The real-time air temperature and real-time heating power of the air duct are explained as follows: To achieve the user's desired temperature for the material, the temperature control system needs to heat the air in the air duct, exchanging heat between the hot air and the material to increase the material's temperature. The real-time air temperature displays the temperature of the air flowing towards the material in the air duct, i.e., the air before it reaches the multi-layer bracket rotating support 7. The real-time heating power of the air duct indicates the current amount of heat being supplied to the air in the air duct; it is the power currently energized by the air duct heating element 12.

[0037] The radiant temperature and radiant power of a real-time heating ceramic plate are explained as follows: The radiant temperature of the real-time heating ceramic plate is its current temperature. The heating ceramic plate contains heating resistors; current flowing through these resistors generates heat, which raises the temperature of the ceramic plate. The heating ceramic plate radiates electromagnetic waves, and its total radiated energy density is proportional to the fourth power of its temperature (absolute temperature scale) (Steffen-Boltzmann law). In the absence of energy loss, according to the law of conservation and transformation of energy, the radiant power of the heating ceramic plate is equal to the electrical power generated when a voltage is applied to the electrodes of the heating resistors inside the plate. Therefore, the real-time radiant power of the heating ceramic plate can be represented by the current electrical power of the total heating resistors within the plate.

[0038] Real-time material temperature refers to the current temperature of the material.

[0039] Specifically, the target parameter combination includes the area of ​​the target controllable outlet 15 and the flow velocity of the target controllable outlet 15 / inlet 16, the target air temperature and the target air heating power, the number of controllable point temperatures in the target air temperature rise process and the time taken for the controllable point temperatures in adjacent target air temperatures rise process, and the combination of the radiation temperature of the target heating ceramic plate and the radiation power of the target heating ceramic plate.

[0040] The area of ​​the target controllable flow outlet 15 and the flow velocity of the target controllable flow outlet 15 / inlet 16 are described and expressed as follows: The target controllable outflow area and the target controllable inflow area 16 are both fixed in size in the implementation of the present case. The air outlet plate 6 is a stainless steel plate that is the same height and width as the multi-layered tray rotating support 7, and the plate is distributed with a two-dimensional array of small holes, which are used for the outflow of air in the air duct to the multi-layered tray rotating support 7. The total area of these small holes is the target controllable outflow area 15. Similarly, the air inlet plate 13 is also a stainless steel plate that is the same height and width as the multi-layered tray rotating support 7, and the plate is distributed with a two-dimensional array of small holes. These small holes are used for the inflow of air in the air duct to the multi-layered tray rotating support 7. The total area of these small holes is the target controllable inflow area. In the implementation, several plates of the same size can be made, and the size of the small holes or the density of the small hole distribution is different, so that there are different total areas of the small holes, which are temporarily selected and combined into the electric baking equipment by the user according to different materials. In such an embodiment, the real-time controllable outflow area 15 and the target controllable outflow area 15 are both the total area of the small holes on the air outlet plate 6. The target controllable inflow area 16 and the real-time controllable inflow area 16 are both the total area of the small holes on the air inlet plate 13. In the case where the air inlet plate 13 and the air outlet plate 6 are the same size, the plate used as the air inlet plate 13 and the plate used as the air outlet plate 6 can be used interchangeably.

[0041] The target controllable outflow area 15 flow rate refers to the flow rate of air flowing out of the target controllable outflow area 15. In the case of using the air outlet plate 6, it refers to the speed of air flowing out of the small holes on the air outlet plate 6 when flowing through the small holes. The target controllable inflow area 16 flow rate refers to the speed of air flowing into the target controllable inflow area 16. In the case of using the air inlet plate 13, it refers to the speed of air flowing into the small holes on the air inlet plate 13 when flowing through the small holes.

[0042] How to control the target controllable outflow area 15 flow rate and the target controllable inflow area 16 flow rate. In the implementation of the present case, an exhaust flow valve and an inlet flow valve are installed at the exhaust port of the box 2 and the inlet port of the box 2 respectively. Between the exhaust port of the box 2 and the air outlet plate 6 is the exhaust cavity 8. Adjusting the exhaust flow valve, the amount of air flowing out of the exhaust port of the box 2 per unit time changes, and the air pressure in the exhaust cavity 8 changes, and the speed of air flowing out of each small hole of the air outlet plate 6 also changes. Similarly, between the inlet port of the box 2 and the air inlet plate 13 is the inlet cavity 14. Adjusting the inlet flow valve, the air pressure in the inlet cavity 14 changes, and the flow rate of air flowing into the small holes on the air inlet plate 13 changes.

[0043] The target air duct temperature and the target air duct electric heating power are described as follows: The target air temperature of the air duct is set by the user, which is the temperature of the air flowing to the rotating support 7 of the multi-layered carrier in the air duct in the box 2 desired by the user. The target air heating power of the air duct indicates that after the user sets the target air temperature of the air duct and specifies the time used to reach the temperature from the current temperature, the temperature control system automatically adjusts the power of the air duct heating element 12 to be started according to the total mass of the air in the air duct and the temperature and time set by the user, so as to meet the user's requirements for temperature and time.

[0044] The number of target air temperature rising process controllable point temperatures of the air duct and the time used by the adjacent target air temperature rising process controllable point temperatures are described and expressed as follows: In the temperature rising process, the difference between the normal temperature and the target air temperature of the air duct is the largest. If the air duct heating element 12 is started at the maximum power, the time used for temperature rising is the shortest. However, the thermal inertia in this case is the largest. This is not conducive to the user's roasting control of the tea and other materials which need to be roasted at a specific temperature to allow the internal micro-reaction of the materials to proceed fully. Obviously, between the two temperatures with the largest difference, a number of controllable point temperatures are inserted, so that the difference between adjacent temperatures in the temperature rising process can be very small, and the time required can be long enough. Therefore, it is required that the power of the execution element is adjustable, and the target air heating power of the air duct that can be adjusted by the temperature control system has a wider range. The number of target air temperature rising process controllable point temperatures is also better.

[0045] The target heating ceramic plate radiation temperature and the target heating ceramic plate radiation electric power are described and expressed as follows: The inside of the heating ceramic plate is a heating resistance circuit. Different voltages are applied to the two electrodes of the heating plate, and the current flowing through the resistance is different, so the electric power of the heating is different. The heat energy converted by the electric energy is all conducted and absorbed by the material of the heating ceramic plate. The temperature of the heating ceramic plate after absorbing the heat energy rises. The air in contact with the surface of the heating ceramic plate will take away part of the heat energy in the heating ceramic plate in the form of heat exchange. The air after absorbing the heat energy can enter the air duct or avoid entering the air duct. Avoiding entering the air duct is beneficial to the independent and accurate completion of the task of the air duct electric heating element 12, and is also beneficial to the temperature rise of the heating ceramic plate. After the heat energy converted by the electric energy is all absorbed by the heating ceramic plate to become the heat energy in the ceramic plate, in addition to the part of the heat energy in the ceramic plate taken away by the air in contact with the surface of the ceramic plate, in the case of high radiation rate, most of the heat energy in the ceramic plate will be radiated outward in the form of radiation energy, and will be radiated onto the multi-layer carrier rotating support 7. Because the total radiation energy density is proportional to the fourth power of the absolute temperature of the heating ceramic plate, it is very important to maintain the radiation of the heating ceramic plate at a certain absolute temperature. When the target heating ceramic plate radiation temperature is set, the temperature control system determines the voltage loaded on the two electrodes of the heating ceramic plate according to the heat energy generated by the current flowing through the internal resistance of the heating ceramic plate, so as to generate the power required to maintain this temperature, which is the target heating ceramic plate radiation electric power.

[0046] The target material temperature is expressed as follows: the target material temperature is the temperature that the user hopes the material on the multi-layer carrier rotating support 7 can reach. This parameter helps the user to use the best temperature discovered by people in the experiment of baking tea and other materials. When the user finds that the real-time material temperature deviates from the target material temperature, the user can choose and set whether the target heating ceramic plate radiation electric power and the target air duct electric heating power of the air duct electric heating element 12 in the temperature control system are associated with each other. If the associated execution is selected, the air heating and radiation heating will realize the temperature rise of the material in a joint power according to the associated proportion.

[0047] The performance parameter combination has the combination of the slowest air duct conveying flow (volume), the fastest air duct conveying flow (volume), the maximum air duct electric heating element 12 electric heating power, the maximum heating ceramic plate radiation electric heating power, and the maximum air duct air temperature rise process controllable point temperature number.

[0048] Among them, the slowest air duct conveying flow (volume) and the fastest air duct conveying flow (volume) are expressed as follows: The air flowing in the air duct simulates the air flow in the charcoal roaster. When the fire is strong in the charcoal roaster, the air speed flowing to the material is fast, and when the fire is controlled, or in the initial stage of combustion, or in the final stage of combustion, the air speed flowing to the material is the slowest. Therefore, the slowest air duct conveying flow (volume), that is, how much flow when the air flow is the slowest, indicates how much hot air per unit time participates in heat exchange with the material when the "fire" is the weakest. And the fastest air duct conveying flow (volume), that is, how much flow when the air flow is the fastest, indicates how much hot air per unit time participates in heat exchange with the material when the "fire" is the strongest. The charcoal roaster roasts through the appropriate fire obtained by covering ash, and the electric roasting equipment in the case obtains the "fire" size between the slowest air duct conveying flow (volume) and the fastest air duct conveying flow (volume) by operating the flow valve and the power and speed of the fan 5. The greater the difference between the two, the more "fire" sizes the user can choose.

[0049] The maximum air duct electric heating element 12 electric heating power is described as follows: The air duct electric heating element 12 for heating the air in the air duct has its rated power, which is the electric heating power of the execution element at the rated voltage. This electric heating power is the maximum air duct electric heating element 12 electric heating power. In order to obtain an average electric heating power lower than the maximum air duct electric heating element 12 electric heating power, the temperature control system usually uses intermittent power-on to obtain an average power lower than the rated power. This average power is the target air duct electric heating power required by the temperature control system. Therefore, the size of the maximum air duct electric heating element 12 electric heating power determines the range of the average electric heating power, and thus determines the number of target air duct air temperature rise process controllable point temperatures that the user can set and the time used by adjacent target air duct air temperature rise process controllable point temperatures.

[0050] The maximum heating ceramic plate radiant electric heating power is described as follows: The heating ceramic plate used for constructing the radiation wall 9 is a non-standard power element. When the internal resistance circuit is connected to the current, the heat generated by the internal resistance circuit is directly conducted to the material constituting the heating ceramic plate. With the absorption of heat, the temperature of the heating ceramic plate is continuously increased. The total radiation energy density radiated outward by the heating ceramic plate is proportional to the fourth power of the absolute temperature of the heating ceramic plate. The radiation energy is converted from the electric energy. The greater the consumed electric energy, the greater the radiated radiation energy, and the higher the temperature of the heating ceramic plate during radiation. According to the Wien displacement law, the product of the wavelength λ and the temperature T corresponding to the peak value of the radiation energy density curve is equal to 2898 μm•K. When the wavelength of the resonant absorption photon of the material is given, the Celsius temperature t of the ceramic plate is 2898 / λ-273.15, wherein the unit of the wavelength λ is μm, and the unit of the Celsius temperature t is ℃. Therefore, in the case that different materials have different resonant absorption wavelengths or the same material has multiple resonant absorption wavelengths, or other wavelengths with high absorption appear beside the resonant absorption wavelength of the material, the ceramic plate needs to be adjusted to the corresponding temperature. The heating ceramic plate is adjusted by adjusting the power to adjust the radiation temperature. The greater the maximum heating power of the ceramic plate, the greater the adjustable power range, and the greater the corresponding adjustment of the radiation temperature range. The heating ceramic plate is adjusted by adjusting the power to adjust the radiation temperature. The greater the maximum heating power of the ceramic plate, the greater the adjustable power range, and the greater the corresponding adjustment of the radiation temperature range.

[0051] The number of controllable point temperatures of the air temperature rise process in the maximum air duct is described as follows: The number of controllable point temperatures of the air temperature rise process in the maximum air duct needs to be sufficient. There are four limitations and requirements: first, the heat released by the air duct electric heating element 12 needs to be fully mixed with the original air, and the change in the temperature of the mixed air needs to be responded by the sensor in the air duct and detected by the temperature control system. Second, the power of the air duct electric heating element 12 used for convection heating is limited, and the power of the air duct electric heating element 12 is only in the adjustable range to supply heat to the air in the air duct. Third, the temperature rise is subject to time constraints, which is a requirement for user operation. Fourth, when the material resonantly absorbs the radiation energy from the radiation wall 9, the material temperature of the material itself is appropriate, and the time required to heat the material to the appropriate temperature by convection heating is a subject that people are exploring and need to be further studied.

[0052] The above-mentioned real-time controllable outlet 15 area and target controllable outlet 15 area are the sum of the areas of all array holes of the air outlet plate 6; the real-time controllable inlet 16 area and target controllable inlet 16 area are the sum of the areas of all array holes of the air inlet plate 13; the real-time controllable outlet 15 flow rate and target controllable outlet 15 flow rate are controlled by the exhaust valve installed at the exhaust port of the cabinet 2 by changing the air flow rate discharged to the outside to change the pressure in the exhaust cavity 8; the real-time controllable inlet 16 flow rate and target controllable inlet 16 flow rate are controlled by the automatic regulating air valve installed at the air inlet of the cabinet 2 by changing the air flow rate sucked from the outside to change the pressure in the air inlet cavity 14. The total area of all holes on the air inlet plate 13 and the total area of all holes on the air outlet plate 6 remain unchanged during baking, and the air duct is closed around, so under steady-state conditions, the air flow rate flowing into the cabinet from the outside through the automatic regulating air valve at the air inlet of the cabinet 2 is equal to the air flow rate discharged to the outside through the exhaust valve at the exhaust port of the cabinet 2. Therefore, the flow rate discharged from the exhaust port of the cabinet 2 or the amount of fresh air charged into the air duct from the air inlet of the cabinet 2 can equally describe the air speed of the numerous holes on the air outlet plate 6 or the numerous holes on the air inlet plate 13. Therefore, the significance of setting the flow rate of the flow valve or the flow rate of the automatic regulating air valve on the human-computer interaction interface touch display screen is to adjust the air speed entering the multi-layer tray rotating support 7 or the air speed leaving the multi-layer tray rotating support 7.

[0053] A one-way air valve is installed on the partition plate 11, and in the case of closing the air inlet of the cabinet 2 and the exhaust port of the cabinet 2, the air fan 5 drives the air in the air duct to flow in a forced circulation manner. The one-way air valve allows the air in the exhaust cavity 8 to pass through the one-way air valve into the air inlet cavity 14; and the air in the air inlet cavity 14 can only reach the exhaust cavity 8 after passing through the air inlet cavity 14 and the multi-layer tray rotating support 7, and cannot directly enter the exhaust cavity 8 in reverse. During the forced circulation of the air in the air duct, the total air mass in the air duct remains unchanged, and the heat released by the air duct heating element 12 can be used to quickly raise the temperature of the air for convection heating.

[0054] The time for setting the above-mentioned target air duct air temperature rising process controllable point temperature and the adjacent target air duct air temperature rising process controllable point temperature is divided into three stages: the first stage of baking, the second stage of flavoring, and the third stage of cooling. The first stage of baking is a rapid heating stage, and the electric heating power of the air duct heating element 12 can be operated at the maximum power to raise the real-time air duct air temperature to the flavoring temperature of the material. The second stage of flavoring is a flavoring baking according to the flavoring temperature and time of the material. The third stage of cooling is to close the electric heating power of the air duct heating element 12 to lower the temperature of the material to room temperature. If necessary, multiple temperature control point temperatures can be inserted in the same stage.

[0055] Actual application of tea making example: 1. Material preparation: Place the green tea with a moisture content of 7-8% to be baked into the stainless steel wire mesh drying box 2, control the stacking thickness to be 20mm, place the box 2 layer by layer on the multi-layer bracket rotating support 7 (13), close the sealing door 3 (5); 2. Parameter setting: Set through the touch screen: Stage parameters: first stage (65℃, 45 minutes), second stage (100℃, 15 minutes), third stage (room temperature, 15 minutes); Radiation parameters: first stage radiation power 50%, second stage 75%, third stage 0%; Flow parameters: first stage air valve flow 75%, second stage 15%, third stage 100%; 3. Start operation: Start the equipment, the temperature control system automatically adjusts the power of the air duct heating element 12 (23) and the radiation wall 9 (17), the fan 5 (9) drives air flow, and the real-time parameter combination (material temperature, air duct temperature, etc.) is displayed on the touch screen; 4. Real-time control: The temperature control system monitors each parameter in real time, and when there is a deviation between the real-time parameter combination and the target parameter combination, automatically adjusts the air duct heating power, the radiation wall 9 power or the air valve opening degree to ensure process stability; 5. End of material removal: After the equipment runs to the end of the third stage, it automatically stops, opens the sealing door 3, removes the drying box 2, and completes the baking of green tea.

[0056] This case simulates a charcoal baking oven, using convection heating and radiation wall 9 heating as two heat sources, which is equivalent to separating air convection heating and thermal radiation in charcoal fire, achieving a significant increase in the amount of baked materials, thereby achieving the following characteristics of the baked materials (taking the above green tea as an example): 1. Appearance Color: The surface of the tea leaves will become more shiny and lustrous due to the loss of water and changes in substances during the baking process. For example, the original green tea may change from emerald green to dark green or black green, and it looks more compact and dry, giving a visual impression of better quality.

[0057] Strands (form): After baking, the tea leaves will become more tightly connected. This is because high temperature further reduces the moisture content in the tea leaves, making the internal structure of the tea leaves more compact, and the originally loose parts will shrink, making the overall form of the tea leaves more regular and compact, which is beneficial for the storage and transportation of tea leaves.

[0058] 2. Aroma Rich aroma type: The roasting process of the composite heat source roasting aroma machine can promote the transformation and release of aroma components in tea leaves, making the aroma type more diverse. In addition to the original green tea aroma, such as fresh and tender aroma, unique roasted aroma, such as chestnut aroma and grain aroma, will also be produced, giving people a comfortable olfactory experience. At the same time, some hidden aroma in tea leaves, such as floral and fruity aroma, may also be triggered, making the overall aroma more rich and harmonious. Strong and lasting aroma: The aroma concentration of roasted green tea will be significantly improved. During the brewing process, the aroma can be quickly released and last for a long time. Compared with unroasted green tea, its aroma disperses faster in the tea soup and can maintain a strong and lasting aroma in the air for a long time, giving people a strong olfactory impact and enhancing the appeal of tea leaves.

[0059] 3. Taste Rich and sweet aftertaste: After roasting, the taste of green tea becomes more mellow. This is because the tea polyphenols and other components in tea leaves undergo certain transformation during the roasting process, and the bitter and astringent taste is relatively reduced, while the relative content of amino acids, soluble sugars and other substances that are fresh and sweet increases or their composition changes, making the tea soup more soft and full. After swallowing the tea soup, there will be a clear sweet aftertaste in the mouth, and the duration of this sweet aftertaste is longer, giving people a pleasant taste enjoyment.

[0060] Enhanced thickness: Roasting makes the internal substances of tea leaves more concentrated, and the taste of tea soup becomes thicker and more textured. Compared with unroasted green tea, the tea soup of roasted green tea has a more obvious sticky and fullness in the mouth, like silk sliding from the tip of the tongue, making people feel that the "flavor" of tea is more sufficient.

[0061] 4. Soup color Brighter color: Due to the removal or transformation of some impurities and undesirable components in tea leaves during the roasting process, as well as the rearrangement and combination of internal components, the transparency and brightness of the tea soup are improved. The soup color of green tea usually becomes clearer and brighter, showing a bright green, yellow-green or green-yellow color, giving people a fresh and pure visual experience.

[0062] Improved stability: The color of roasted green tea is relatively more stable during brewing. After a period of storage, its color changes slowly and is less likely to appear dark or quickly change color like unroasted green tea, which is beneficial to maintaining the stability of tea quality and is more convenient to drink.

[0063] 5. Leaf bottom Uniform and glossy color: the baked green tea leaves have more uniform and consistent color and are rich in luster. Because the tea leaves are evenly heated during baking, the pigment components in the leaves are well protected and transformed, and the leaf bottom does not have phenomena such as uneven color, color spots, etc., presenting a natural and healthy color such as yellow-green, green-brown, etc.

[0064] Suitable softness: although the moisture of the baked tea leaves is reduced, the softness of the leaf bottom is still maintained in a good state. The leaf bottom is soft and has a certain elasticity, and does not have phenomena such as dryness, brittleness, etc., which indicates that the internal structure of the tea leaves is not damaged during baking, and the quality is well preserved.

Claims

1. A tea electric roasting apparatus for composite heat transfer by convection heating in combination with a radiant wall 9, The utility model relates to a kind of drying cabinet, including: its characterized in that: Box (2) and multilayer bracket rotating support (7), the box (2) is with sealing door (3), sealing door (3) forms closed space, only through inlet (16) and outlet (15) with outside communication, guarantee baking environment stability;Sealing door (3) is convenient for material to go up and take down;The multilayer bracket rotating support (7) is used to place the drying box (2) containing material, by motor (1) drive around vertical direction rotating support pivot (10) rotation, ensure that the material on each layer bracket receives radiation heating and convection heating evenly; Forced convection heating mechanism, including fan (5), air duct electric heating element (12) and air duct structure;Fan (5) is installed on the air duct of box (2), air duct is communicated with outside through inlet (16) and outlet (15), and pass through multilayer bracket rotating support (7) in box (2), realize that hot air is contacted with material fully;Air duct is equipped with baffle (11), prevent airflow short circuit;Baffle (11) is installed one-way air valve, when closing inlet (16) and outlet (15), can realize that air in air duct is forced circulation, rapidly promote air temperature; Radiation electric heating mechanism has heating ceramic plate, heating ceramic plate is erected in box (2) with multilayer bracket rotating support (7) is in the interval, ensure that material receives radiation heating all directions; Electric control mechanism (4), including temperature control system and touch display screen;Temperature control system realizes to the real-time monitoring and automatic control of air duct air temperature, radiation wall (9) temperature, material temperature; Touch display screen supports target parameter combination setting and real-time parameter combination, performance parameter combination display, convenient operation.

2. The tea electric roasting apparatus of claim 1, wherein the tea electric roasting apparatus is characterized by: The electric control mechanism (4) establishes real-time parameter combination, target parameter combination, performance parameter combination three parameter systems, realizes the accurate control of baking process, as follows specifically: a. Real-time parameter combination: reflects the current operating state of the equipment, including: Fluid parameters: real-time controllable outlet (15) area / flow rate, real-time controllable inlet (16) area / flow rate; Temperature and power parameters: real-time air duct air temperature, real-time air duct electric heating power, real-time heating ceramic plate radiation temperature / power, real-time material temperature; b. Target parameter combination: set by the user according to the material characteristics, including: Fluid parameters: target controllable outlet (15) area / flow rate, target controllable inlet (16) area / flow rate; Temperature and power parameters: target air duct air temperature / electric heating power, target heating ceramic plate radiation temperature / power, target material temperature; Process parameters: target air duct air temperature rise process controllable point temperature number and adjacent controllable point temperature time used, i.e. support segmented setting; c. Performance parameter combination: reflects the operating capacity of the equipment, including: Fluid performance: slowest / fastest air duct delivery flow (volume); Power performance: maximum air duct electric heating element (12) electric heating power, maximum heating ceramic plate radiation electric heating power; Control performance: maximum air duct air temperature rise process controllable point temperature number.

3. The tea electric roasting apparatus of claim 2, wherein the tea electric roasting apparatus is characterized by: The drying box (2) is made of stainless steel mesh, which facilitates radiation penetration and air circulation.

4. The tea electric roasting apparatus of claim 3, wherein the tea electric roasting apparatus is characterized by: The size of the heating ceramic plate is not less than the parallel projection of the multi-layer bracket rotating support (7) on the plate surface, and the plate surface is flat.

5. The tea electric roasting apparatus of claim 4, wherein the tea electric roasting apparatus is characterized by: The area of ​​the real-time controllable flow outlet (15) and the area of ​​the target controllable flow outlet (15) are the total area of ​​the small holes in the air outlet plate (6) array, and the area of ​​the real-time controllable flow inlet (16) and the area of ​​the target controllable flow inlet (16) are the total area of ​​the small holes in the air inlet plate (13) array. The adjustment is made by replacing the air outlet plate (6) / air inlet plate (13) with different hole densities.

6. A tea electric roasting method using the tea electric roasting equipment of claim 5, which combines convection heating with radiant walls for composite heat transfer, comprising the following steps: characterized in that: a. Material preparation: Place the tea leaves to be roasted into the stainless steel wire mesh drying box (2), control the thickness of the stack, place the box (2) layer by layer on the multi-layer bracket rotating support (7), and close the sealing door (3). b. Parameter settings: Users can set the following parameters via the touch screen: Segmented process parameters: The air temperature rise process in the air duct is divided into three stages: the first stage of baking (rapid heating), the second stage of aroma enhancement (constant temperature aroma preservation), and the third stage of cooling (cooling down to room temperature). The target temperature and duration of each stage are set. Radiation and convection parameters: radiation temperature / power of target heating ceramic plate, flow velocity of target inlet (16) / outlet (15); Material parameters: target material temperature, used for coordinated control of radiation and convection power; c. Start running: After a cold start, the fan (5) starts, and fresh air from the outside enters the air duct through the air inlet automatic regulating valve. After being heated by the air duct heating element (12), it flows through the air inlet cavity (14) and the small holes of the air inlet plate (13) to the multi-layer bracket rotating support (7) for heat exchange with the material. The radiation wall (9) starts synchronously and releases infrared radiation to the material. The multi-layer bracket rotating support (7) rotates to ensure that the material is heated evenly. After heat exchange, the air enters the exhaust chamber (8) through the small hole of the air outlet plate (6) and is discharged to the outside through the exhaust port flow valve; when the inlet / outlet is closed, the one-way air valve opens and the air circulates and heats in the air duct; d. Real-time control: The temperature control system monitors each parameter in real time. When there is a deviation between the real-time parameter combination and the target parameter combination, it automatically adjusts the electric heating power of the air duct, the power of the radiant wall (9) or the opening of the air valve to ensure process stability. e. End of material handling: After the equipment has run to the end of the third stage, it will automatically stop, open the sealed door (3), take out the drying box (2), and complete the green tea roasting.

7. The electric roasting method for tea leaves using a combination of convection heating and radiant wall for composite heat transfer, as described in claim 6, is characterized in that: The flow rate at the outlet (15) is achieved by adjusting the air inlet valve and the exhaust flow valve of the box (2).

8. The tea electric baking method of claim 7, wherein the tea electric baking method is characterized in that: The touch screen displays the controllable temperature of the air temperature rise process in each target air duct and the time taken for the controllable temperature of the air temperature rise process in adjacent target air ducts. Set the target radiant temperature of the heating ceramic plate or the target radiant power; set the flow rate of the flow valve or the flow rate of the automatically regulating air valve; The touch screen displays the real-time material temperature and the real-time air temperature in the air duct.

9. The electric roasting method for tea leaves using a combination of convection heating and radiant wall for composite heat transfer as described in claim 8, characterized in that: The controllable temperature of the air temperature rise process in each target air duct and the time taken for the controllable temperature of the air temperature rise process in adjacent target air ducts are divided into three stages: the first stage is baking, the second stage is aroma enhancement, and the third stage is cooling.

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