Tobacco leaf curing process in middle of flue-cured tobacco container curing barn

Abstract

The invention discloses a flue-cured tobacco container curing barn middle tobacco leaf curing process which is characterized by comprising the steps of flue-cured tobacco airflow descending type container curing barn preparation before curing and flue-cured tobacco airflow descending type container curing barn middle tobacco leaf curing process. The flue-cured tobacco airflow descending type container curing barn is prepared before curing, after the curing barn is sealed, ignition furnace testing is carried out, furnace charging is carried out according to the'full and uniform 'standard, furnace charging is carried out in an'echelon distribution' mode, a tobacco loading chamber of the curing barn is transversely divided into three parts, the tobacco loading number of a high-temperature layer on the side of a heat insulation wall serves as the standard, and the tobacco loading number of the high-temperature layer from the heat insulation wall to a furnace door is gradually decreased by one rod in an echelon mode. One side of the heat insulation wall of the low-temperature layer and the middle part of the low-temperature layer are respectively reduced by one rod compared with the middle layer, and the cigarette loading quantity of one side of the furnace door is consistent with that of the middle layer; the dry tobacco quality and the first-class tobacco proportion can be improved, and the average price of the dry tobacco is further increased.

Description

Technical Field

[0001] The invention relates to the technical field of tobacco leaf baking, and in particular to a tobacco leaf baking process in the middle of a tobacco container baking house. Background Art

[0002] In recent years, with the urbanization and modernization of rural areas, characteristic agricultural industries such as grain, oil, cash and feed have shown the characteristics of scale and intensiveness. As far as the flue-cured tobacco industry is concerned, it is increasingly obvious that large agricultural crops compete with tobacco for land and people. In addition, with the active adjustment of the planting layout of tobacco areas, flue-cured tobacco planting has gradually become marginalized and scattered. Some old tobacco areas have gradually withdrawn from flue-cured tobacco planting, and tobacco facilities such as flue-curing houses have turned to the development of other industries. Since 2022, Shandong tobacco areas have seized the national trend of tobacco leaves "turning from stability to growth", gradually expanded the scale of planting, increased the flue-cured tobacco contract planting plan, and in order to solve the problem of supporting flue-curing houses for newly added tobacco fields, a batch of container flue-curing houses have been uniformly installed and equipped throughout the province. Facts have proved that container flue-curing houses are movable, have a large tobacco loading capacity, and have good thermal insulation performance. They effectively solve the problems of idle flue-curing houses with intensive civil engineering and insufficient supporting flue-curing houses in newly planned tobacco areas due to adjustments to the layout planning of tobacco areas.

[0003] The overall length of the container curing room is longer. Under the conditions of the same power fan, the wind speed is lower than that of the conventional intensive curing room. In terms of internal components, it is easier to promote the transformation and accumulation of internal components of tobacco leaves, reduce the loss of small molecule aroma substances, and increase the aroma of tobacco leaves after curing. In terms of appearance quality, the lower wind speed can effectively reduce the proportion and probability of smooth and stiff tobacco leaves, and improve the appearance quality of tobacco leaves.

[0004] Chinese patent CN108208905B discloses a baking process that effectively solves the problem of ash hanging on the upper tobacco leaves. The process adopts the tobacco rod weaving method and is divided into 9 stages according to the changing state of tobacco leaves during the baking process: the stage when the leaves turn yellow 70% to 80% and the leaf tips and edges become soft, the stage when the leaves turn yellow 90% and the mesophilic tobacco leaves begin to curl, the stage when the leaves turn yellow and have green veins and the mesophilic tobacco leaves reach the small tube stage, the stage when the tobacco leaf veins are completely yellow and the mesophilic leaves are 2 / 3 dry, the stage when the leaves turn yellow and have yellow veins and the leaves are completely dry, the stage when the tobacco veins begin to dry, and the stage when the base of the tobacco veins begin to turn brown , the tobacco ribs shrink and turn brown, the stage of drying more than 2 / 3, and the stage of complete drying of the tobacco ribs; 9 key temperature and humidity precise control points are set, and the baking process is accurately quantified, which greatly reduces baking errors, simplifies the baking process, automates baking, and accurately controls the time and speed changes of temperature and humidity. The tobacco leaves can be taken out in time to prevent the upper tobacco leaves from being covered with ash due to uneven time and temperature changes, thereby improving the baking quality of the tobacco leaves; however, due to the poor effect of regulating the air volume, the quality of dry tobacco is reduced, the proportion of high-quality tobacco is low, and the average price of dry tobacco is further reduced. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room, which can improve the quality of dry tobacco and the proportion of high-quality tobacco, and further increase the average price of dry tobacco.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: A tobacco leaf baking process in the middle of a flue-cured tobacco container curing barn, comprising: preparation before baking in a flue-cured tobacco airflow-downward container curing barn, and a tobacco leaf baking process in the middle of a flue-cured tobacco airflow-downward container curing barn; The flue-cured tobacco airflow descending container curing room is prepared before baking. After the curing room is sealed, the furnace is ignited for testing, and the furnace is loaded. The furnace is loaded according to the "dense, full and uniform" standard, and the furnace is loaded in a "step distribution" manner. The smoke loading chamber of the curing room is divided into three parts horizontally. The number of smoke loaded in the high-temperature layer on the side of the insulation wall is used as a benchmark. The number of smoke loaded in the high-temperature layer from the insulation wall to the furnace door is stepped down by 1 rod, and the number of smoke loaded in the middle layer is the same as that in the high-temperature layer. The one side and the middle part of the insulation wall of the low-temperature layer are each one rod less than the middle layer, and the amount of smoke loaded on the furnace door side is the same as that in the middle layer; The baking room is transformed from an abandoned container and adopts a downward airflow type air supply; The curing room includes a multi-purpose heating device for coal and biomass particles, a fan duct, a moisture exhaust port, and an observation window. The curing room is 12m long, the smoke loading chamber is 9.5m long, and a single furnace can load 300-320 smoke rods; The smoke chamber of the curing room has three dehumidification ports on both sides of the bottom, and a control iron sheet is installed at each dehumidification port to control the switch and opening degree of the dehumidification port; The flue-cured tobacco leaf baking process in the central part of the flue-cured tobacco airflow descending container flue-curing room includes: a yellowing stage, a color fixing stage, and a tendon drying stage; The yellowing stage includes: a first step, a second step, a third step, and a fourth step; The color fixing stage includes: a fifth step, a sixth step, a seventh step, and an eighth step; The dry tendon stage includes: step nine, step ten; In the first step, the dry bulb temperature is 36°C, the wet bulb temperature is 36°C, after ignition, the moisture outlets are all closed with control iron sheets, the temperature is raised to 36°C at a rate of 1°C / h, the temperature is stabilized, and the fan is operated at a low speed until there is no visible water on the blade surface; In the first step, the cold air door and the curing room door are manually closed, and the fan is turned on for high-speed internal circulation for 0.5-1h. For tobacco leaves with high moisture content, the cold air door and the curing room door are opened, and the fan is turned on for high-speed circulation; In the second step, the dry bulb temperature is 38°C and the wet bulb temperature is 37°C. The temperature is raised to 38°C at a rate of 1°C / h and the temperature is kept constant until the tips of the middle tobacco leaves become warm and soft. In the second step, the dehumidification ports are all closed with control iron sheets, and the fan is running at a low speed. If a large amount of condensed water droplets appear in the observation window, it means that the wet bulb temperature exceeds 37.5°C. Rotate the dehumidification port iron sheet to open 1 / 3 of the 4 dehumidification ports on the side and middle of the furnace door. If the humidity is appropriate, it does not need to be opened. In the third step, the dry bulb temperature is 40°C and the wet bulb temperature is 37°C, and the temperature is raised to 40°C at a rate of 0.5°C / h, and the temperature is stabilized until the middle leaves lose water and wilt and collapse, and turn yellow until both sides of the leaf veins are partially green and the rest are yellow; In the third step, from the beginning of the temperature rise, the dehumidification port iron sheet is rotated to open 1 / 3 of the four dehumidification ports on the side and middle of the furnace door, and the fan is turned on at high speed; In the fourth step, the dry bulb temperature is 42° C. and the wet bulb temperature is 37° C., and the temperature is raised to 42° C. at a rate of 0.5° C. / h, and the temperature is stabilized until the middle tobacco leaves lose water and the main veins become soft and can be twisted around fingers, and the upper tobacco leaves dry and turn yellow to basically yellow leaves with blue veins; In the fourth step, 1 / 2 of the 4 dehumidification ports on the side and middle of the furnace door and 1 / 3 of the 2 dehumidification ports on the side of the insulation wall are opened, and the fan is operated at high speed. If the yellowing speed is faster than the water loss speed, the wet bulb temperature is gradually adjusted to 36°C in the temperature stabilization, and then 2 / 3 of the 4 dehumidification ports on the side and middle of the furnace door and 1 / 2 of the 2 dehumidification ports on the side of the insulation wall are opened; In the fifth step, the dry bulb temperature is 45°C and the wet bulb temperature is 37°C, and the temperature is raised to 45°C at a rate of 0.5°C / h, and the temperature is stabilized until the middle leaves lose water to the point of curling and turn yellow to yellow leaves and veins; In the fifth step, all moisture outlets are completely released and the fan is operated at high speed; In the sixth step, the dry bulb temperature is 47°C and the wet bulb temperature is 37°C. The temperature is raised to 47°C at a rate of 1°C / h and the temperature is stabilized until the middle leaves lose water to 1 / 2 of the dry leaves, present a small roll state, and the yellowing degree reaches a level where there is no green in the whole furnace; In the seventh step, the dry bulb temperature is 50°C, the wet bulb temperature is 38°C, and the temperature is increased to 50°C at a rate of 1°C / h, and the temperature is stabilized until the blades in the low temperature layer are rolled up; In the eighth step, the dry bulb temperature is 54°C and the wet bulb temperature is 38°C. The temperature is raised to 54°C at a rate of 1°C / h, and the temperature is stabilized and baked until all the leaves in the furnace are completely dry and in a large roll state. In the ninth step, the dry bulb temperature is 60°C and the wet bulb temperature is 40°C, and the temperature is raised to 60°C at a rate of 1°C / h, and the temperature is stabilized until the middle layer of tobacco leaves loses water to 2 / 3 of the dry tendons; In the tenth step, the dry-bulb temperature is 68°C and the wet-bulb temperature is 41°C. The temperature is raised to 68°C at a rate of 2°C / h and maintained at a constant temperature until all the tobacco leaves and tendons in the furnace are completely dry.

[0007] Compared with the prior art, the present invention has the following beneficial effects: (1) The tobacco leaf baking process in the middle of the flue-cured tobacco container curing room of the present invention optimizes the baking process, realizes scientific control of temperature and humidity, achieves good quality of tobacco leaves after baking, high grade structure, significant benefits, and realizes integrated optimization and simplification of baking; by manually controlling the size of the dehumidification port during the step-by-step tobacco loading and baking process, the problem of low wind speed on the furnace door side caused by the long tobacco loading room in the container curing room is perfectly solved, and the baking quality of the curing room is effectively improved; (2) The maturity, leaf structure, quality, oil content and chromaticity of the dried tobacco obtained by the flue-cured tobacco container flue-cured barn flue-cured process of the present invention are not significantly different from those of the conventional flue-cured process in the intensive flue-cured barn and the conventional flue-cured process in the airflow-down container flue-cured barn. The maturity is mature, the leaf structure is loose, the quality is medium, the oil content is present and the chromaticity is medium. (3) The tobacco leaf baking process in the middle of the flue-cured tobacco container curing room of the present invention has a fresh tobacco weight of 5000 kg, a dry tobacco weight of 540 kg, a high-quality tobacco ratio of 65.2%, a medium-quality tobacco ratio of 31.4%, a sales weight of 521 kg, and an average price of 30.12 yuan / kg. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic diagram of the number of cigarettes loaded in the cigarette loading chamber in Example 1; Figure 2 This is a schematic diagram of the moisture discharge port in Example 1. DETAILED DESCRIPTION

[0009] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation methods of the present invention are now described.

[0010] Example 1 A process for baking tobacco leaves in the middle of a flue-cured tobacco container curing house, comprising: 1. Preparation before baking in the flue-cured tobacco airflow downdraft container baking room The baking room is converted from abandoned containers and adopts downward airflow. It includes multi-purpose heating equipment for coal and biomass particles, fan ducts, dehumidification ports, and observation windows. The baking room is 12m long and the smoke loading chamber is 9.5m long. A single furnace can hold 300-320 smoke rods (clips).

[0011] (1) Since the baking room is transformed from abandoned containers and has no civil engineering, the sealing of the baking room should be checked before use, including the following two points: Baking room sealing: Use mud to seal all gaps in the furnace head, especially the bottom of the heating chamber, and check whether there is any problem of colloid cracking and air leakage; Ignition test furnace: ignite the furnace before baking to check whether there is air leakage or smoke leakage due to poor sealing of the furnace body; (2) Since the design principle of this type of curing room is based on the design of conventional dense curing rooms, there are 3 dehumidification ports on each side of the bottom of the smoke loading chamber. In actual use, if the furnace is installed according to the "dense, full and uniform" standard, the problem of abnormal dehumidification will occur when the length of the smoke loading chamber increases. When the quality of fresh smoke is poor, this problem will be particularly serious. For this reason, the furnace is installed in a "stepped distribution" manner, that is, the smoke loading chamber of the curing room is divided into three parts horizontally. The number of smoke loaded in the high-temperature layer on the side of the insulation wall is used as the benchmark. The number of smoke loaded in the high-temperature layer from the insulation wall to the furnace door is gradually reduced by 1 rod (clip), and the number of smoke loaded in the middle layer is the same as that in the high-temperature layer. The side of the insulation wall and the middle part of the low-temperature layer are each one rod less than the middle layer, and the amount of smoke loaded on the furnace door side is the same as that in the middle layer. See the schematic diagram of the number of smoke loaded in the smoke loading chamber for details. Figure 1 As shown, there are 2 moisture outlets on the furnace door side, 2 in the middle, and 2 on the insulation wall side.

[0012] In addition, in order to ensure the smooth baking process and better control the moisture in the room, it is necessary to install a control iron sheet at each dehumidification outlet. The control iron sheet can control the switch and opening degree of the dehumidification outlet. See the schematic diagram of the dehumidification outlet. Figure 2 shown.

[0013] 2. Flue-cured tobacco leaf baking process in the middle of the container flue-cured room with downward airflow After the fresh tobacco leaves are loaded into the oven, the tobacco rods are braided and the baking process is divided into three stages: yellowing stage, color fixing stage, and dry rib stage, which specifically include 10 temperature points. In this process, since the size of the tobacco loading room in the baking room is relatively long, manually controlling the size of the moisture outlet is the key to controlling the moisture content of the tobacco leaves in the oven.

[0014] In this process, the specific time of temperature stabilization in each stage is determined by the state.

[0015] Yellowing stage (1) The dry bulb temperature is 36℃, the wet bulb temperature is 36℃, after ignition, the moisture outlet is completely closed with the control iron sheet, starting from the internal temperature of the smoke loading chamber, the temperature is raised to 36℃ at a rate of 1℃ / h, and the temperature is kept stable for 2-4 hours. The fan runs at a low speed to balance the temperature in the furnace. At this stage, first, pay attention to avoid heating too fast and burning too much in the furnace, which will cause the base of the tobacco leaves in the high temperature area to turn green; second, pay attention to manually close the cold air door and the drying room door after the fresh tobacco leaves are loaded into the furnace, and turn on the fan for high-speed internal circulation for 0.5-1h to open the air flow channel, balance the moisture, and replenish oxygen; for tobacco leaves with high moisture content (after rain, dew, etc.), open the cold air door and the drying room door, and turn on the fan for high-speed circulation until there is no visible water on the leaf surface, and then go to step (2).

[0016] (2) The dry bulb temperature is 38°C and the wet bulb temperature is 37°C. The temperature is raised to 38°C at a rate of 1°C / h. The temperature is kept stable for 10-12 hours. The dehumidification ports are all closed with control iron plates. The fan is operated at a low speed. If a large amount of condensed water droplets appear in the observation window, it means that the wet bulb temperature exceeds 37.5°C. Rotate the dehumidification port iron plates and open 1 / 3 of the 4 dehumidification ports on the side and middle of the furnace door. If the humidity is appropriate, there is no need to open them. Wait until the tips of the middle-layer tobacco leaves become warm and soft, and then proceed to step (3).

[0017] (3) The dry bulb temperature is 40℃, the wet bulb temperature is 37℃, and the temperature is raised to 40℃ at a rate of 0.5℃ / h. From the beginning of the temperature rise, rotate the dehumidification iron plate, open 1 / 3 of the 4 dehumidification ports on the side and in the middle of the furnace door, keep the temperature stable for 18-22 hours, and start the fan at high speed. At this stage, pay attention to the coordination of yellowing and water loss. When the middle leaves lose water to the point of withering and collapsing, and turn yellow to the point where there is some green on both sides of the leaf veins and the rest is yellow, proceed to step (4).

[0018] (4) The dry bulb temperature is 42°C and the wet bulb temperature is 37°C. The temperature is raised to 42°C at a rate of 0.5°C / h. The temperature is stabilized for 20-24 hours. 1 / 2 of the 4 dehumidification ports on the side and middle of the furnace door and 1 / 3 of the 2 dehumidification ports on the insulation wall are opened. The fan is operated at high speed. If the yellowing speed is faster than the water loss speed, the wet bulb temperature is gradually adjusted to 36°C during the temperature stabilization. Then 2 / 3 of the 4 dehumidification ports on the side and middle of the furnace door and 1 / 2 of the 2 dehumidification ports on the insulation wall are opened until the middle layer of tobacco leaves lose water and the main veins become soft and can be twisted around fingers. The upper layer of tobacco leaves are dry and tipped. The leaves turn yellow to the point where the leaves are basically yellow with blue veins. Then proceed to step (5).

[0019] Color Fixation Stage (5) The dry bulb temperature is 45°C and the wet bulb temperature is 37°C. The temperature is raised to 45°C at a rate of 0.5°C / h. The temperature is stabilized for 12-16 hours. All moisture outlets are completely released and the fan is operated at high speed until the middle blades lose water to the point of curling and turning yellow. Then proceed to step (6).

[0020] (6) The dry bulb temperature is 47°C and the wet bulb temperature is 37°C. The temperature is raised to 47°C at a rate of 1°C / h. The temperature is kept stable for 12-14 hours until the middle leaves lose water and become 1 / 2 dry, presenting a small roll state. The yellowing degree reaches a point where no green is left in the entire furnace. After this stage, proceed to step (7).

[0021] (7) The dry bulb temperature is 50°C and the wet bulb temperature is 38°C. The temperature is raised to 50°C at a rate of 1°C / h. The temperature is stabilized for 8-10 hours until the blades in the low temperature layer are rolled up, and then the process goes to step (8).

[0022] (8) The dry-bulb temperature is 54°C and the wet-bulb temperature is 38°C. The temperature is raised to 54°C at a rate of 1°C / h and the temperature is kept stable for 15 hours, which is conducive to the full formation of aroma substances. The leaves are baked until they are completely dry and in a large roll state, and then proceed to step (9).

[0023] Dry phase (9) The dry bulb temperature is 60°C and the wet bulb temperature is 40°C. The temperature is raised at a rate of 1°C / h to 60°C. The temperature is kept stable for 8 hours. The fan is operated at a low speed until the middle layer of tobacco leaves loses water to 2 / 3 of the dry tendons. Then proceed to step (10).

[0024] (10) The dry bulb temperature is 68°C and the wet bulb temperature is 41°C. The temperature is raised to 68°C at a rate of 2°C / h and maintained at a steady temperature for 14-20 hours until all the tobacco leaves and tendons in the furnace are completely dry.

[0025] Effect comparison 1 The maturity, leaf structure, identity, oil content and chromaticity of the dried tobacco obtained by the conventional baking process of the intensive flue-curing room, the middle tobacco leaf baking process of the flue-cured tobacco container flue-curing room of Example 1 and the conventional baking process of the airflow descending container flue-curing room were compared. The comparison results are shown in Table 1: Table 1

[0026] It can be seen from the above table that the appearance quality of the dry tobacco baked according to the process of Example 1 is not significantly different from that of the conventional baking process in a dense baking room and the conventional baking process in a downward airflow container baking room.

[0027] Effect comparison 1 The weight of fresh tobacco, the weight of dried tobacco, the proportion of high-quality tobacco, the proportion of medium-quality tobacco, the delivery weight, and the average price used in the conventional baking process of the intensive flue-curing room, the middle tobacco leaf baking process of the flue-cured tobacco container flue-curing room of Example 1, and the conventional baking process of the airflow descending container flue-curing room are compared. The comparison results are shown in Table 2: Table 2

[0028] It can be seen from the above table that after adopting the process of Example 1, the proportion of high-quality tobacco and the average price are significantly improved, and due to the reduction in wind speed, compared with the conventional baking process in a dense baking room, the proportion of high-quality tobacco in the dry tobacco obtained by the process of Example 1 is 8.8% higher, and the average price is 0.48 yuan / kg higher.

[0029] Unless otherwise specified, all percentages used in the present invention are by mass.

[0030] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room, characterized in that: include: Preparation before curing in a flue-cured tobacco container-curing barn with downward airflow, and the process of curing tobacco leaves in the middle of a flue-cured tobacco container-curing barn with downward airflow; The flue-cured tobacco airflow descending container flue-cured barn is prepared before baking. After the flue-cured barn is sealed, the furnace is ignited for testing, and the furnace is loaded. The furnace is loaded according to the "dense, full and uniform" standard, and the furnace is loaded in a "step distribution" manner. The flue-cured barn smoke loading chamber is horizontally divided into three parts. The number of smoke loaded in the high-temperature layer on the side of the insulation wall is used as a benchmark. The number of smoke loaded in the high-temperature layer from the insulation wall to the furnace door is stepped down by 1 rod, and the number of smoke loaded in the middle layer is the same as that in the high-temperature layer. The one side and the middle part of the insulation wall of the low-temperature layer are each one rod less than the middle layer, and the amount of smoke loaded on the furnace door side is the same as that in the middle layer; There are three dehumidification openings on both sides of the bottom of the smoke chamber of the curing room, and a control iron sheet is installed at each dehumidification opening to control the switch and opening degree of the dehumidification opening.

2. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room according to claim 1, characterized in that: The baking room is transformed from an abandoned container and adopts a downward airflow type air supply; The curing room includes multi-purpose heating equipment for coal and biomass particles, fan ducts, moisture exhaust ports, and observation windows. The curing room is 12 meters long, the smoke loading chamber is 9.5 meters long, and a single furnace can load 300-320 smoke rods.

3. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room according to claim 1, characterized in that: The flue-cured tobacco leaf baking process in the central portion of the flue-cured tobacco airflow descending container curing room comprises: a yellowing stage, a color fixing stage, and a tendon drying stage.

4. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room according to claim 3, characterized in that: The yellowing stage includes: a first step, a second step, a third step, and a fourth step; The color fixing stage includes: a fifth step, a sixth step, a seventh step, and an eighth step; The dry tendon stage includes: step nine and step ten.

5. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room according to claim 4, characterized in that: In the first step, the dry bulb temperature is 36°C, the wet bulb temperature is 36°C, after ignition, the moisture outlets are all closed with control iron sheets, the temperature is raised to 36°C at a rate of 1°C / h, the temperature is stabilized, and the fan is operated at a low speed until there is no visible water on the blade surface; In the first step, the cold air door and the drying room door are manually closed, and the fan is turned on for high-speed internal circulation for 0.5-1h. For tobacco leaves with high moisture content, the cold air door and the drying room door are opened, and the fan is turned on for high-speed circulation.

6. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room according to claim 4, characterized in that: In the second step, the dry bulb temperature is 38°C and the wet bulb temperature is 37°C. The temperature is raised to 38°C at a rate of 1°C / h and the temperature is kept constant until the tips of the middle tobacco leaves become warm and soft. In the second step, the dehumidification ports are all closed with control iron sheets, and the fan is running at low speed. If a large amount of condensed water droplets appear in the observation window, it means that the wet-bulb temperature exceeds 37.5°C. Rotate the dehumidification port iron sheets to open 1 / 3 of the 4 dehumidification ports on the side and middle of the furnace door. If the humidity is appropriate, there is no need to open them.

7. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room according to claim 4, characterized in that: In the third step, the dry bulb temperature is 40°C and the wet bulb temperature is 37°C, and the temperature is raised to 40°C at a rate of 0.5°C / h, and the temperature is stabilized until the middle leaves lose water and wilt and collapse, and turn yellow until both sides of the leaf veins are partially green and the rest are yellow; In the third step, from the beginning of temperature rise, the dehumidification port iron sheet is rotated to open 1 / 3 of the four dehumidification ports on the side and middle of the furnace door, and the fan is turned on to run at high speed.

8. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing room according to claim 4, characterized in that: In the fourth step, the dry bulb temperature is 42° C. and the wet bulb temperature is 37° C., and the temperature is raised to 42° C. at a rate of 0.5° C. / h, and the temperature is stabilized until the middle tobacco leaves lose water and the main veins become soft and can be twisted around fingers, and the upper tobacco leaves dry and turn yellow to basically yellow leaves with blue veins; In the fourth step, 1 / 2 of the 4 dehumidification ports on the side and middle of the furnace door and 1 / 3 of the 2 dehumidification ports on the insulation wall side are opened, and the fan is operated at high speed. If the yellowing speed is faster than the water loss speed, the wet-bulb temperature is gradually adjusted to 36°C in a stable temperature state, and then 2 / 3 of the 4 dehumidification ports on the side and middle of the furnace door and 1 / 2 of the 2 dehumidification ports on the insulation wall side are opened.

9. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing barn according to claim 4, characterized in that: In the fifth step, the dry bulb temperature is 45°C and the wet bulb temperature is 37°C, and the temperature is raised to 45°C at a rate of 0.5°C / h, and the temperature is stabilized until the middle leaves lose water to the point of curling and turn yellow to yellow leaves and veins; In the fifth step, all moisture outlets are completely released and the fan is operated at high speed; In the sixth step, the dry bulb temperature is 47°C and the wet bulb temperature is 37°C. The temperature is raised to 47°C at a rate of 1°C / h and the temperature is stabilized until the middle leaves lose water to 1 / 2 of the dry leaves, present a small roll state, and the yellowing degree reaches a level where there is no green in the whole furnace; In the seventh step, the dry bulb temperature is 50°C, the wet bulb temperature is 38°C, and the temperature is increased to 50°C at a rate of 1°C / h, and the temperature is stabilized until the blades in the low temperature layer are rolled up; In the eighth step, the dry bulb temperature is 54°C and the wet bulb temperature is 38°C. The temperature is raised to 54°C at a rate of 1°C / h, the temperature is stabilized, and the leaves in the furnace are baked until they are completely dry and in a large roll state.

10. The process for baking tobacco leaves in the middle of a flue-cured tobacco container curing barn according to claim 4, characterized in that: In the ninth step, the dry bulb temperature is 60°C, the wet bulb temperature is 40°C, and the temperature is increased at a rate of 1°C / h to 60°C, and the temperature is stabilized until the middle layer of tobacco leaves loses water to 2 / 3 of the dry tendons; In the tenth step, the dry-bulb temperature is 68°C and the wet-bulb temperature is 41°C. The temperature is raised to 68°C at a rate of 2°C / h and maintained at a constant temperature until all the tobacco leaves and tendons in the furnace are completely dry.

Images