A method and apparatus for controlling soil-borne diseases by burning straw and stubble.

Abstract

This invention discloses a method and apparatus for controlling soil-borne diseases by burning straw and stubble. The method includes the following steps: S1. Digging multiple smoldering trenches arranged in an array in farmland, filling the trenches with crop stubble and / or straw, installing a perforated cover plate on the upper side of the trenches, and then covering the perforated cover plate with crop stubble and / or straw, followed by soil, and then covering it with an arched shed to form a sealed space; S2. Burning crop stubble and / or straw outside the arched shed, and introducing the high-temperature flue gas generated by the combustion into the smoldering trenches to warm the surrounding soil; S3. Finally, stopping the introduction of high-temperature flue gas into the smoldering trenches, then igniting the crop stubble and / or straw in the smoldering trenches, and maintaining the temperature for a certain period of time to complete the eradication of soil-borne diseases. This application can make full use of the abundant crop straw and stubble resources in farmland to reduce energy consumption and achieve the goal of green prevention and control in agricultural production.

Description

Technical Field

[0001] This invention belongs to the field of agricultural technology, specifically relating to a method and apparatus for preventing soil-borne diseases by burning straw and stubble. Background Technology

[0002] Soil-borne pests and diseases mainly include insect pests and pathogenic microorganisms active in the shallow soil layer, crop roots, and crop stems. They primarily damage the roots and stems of crops and are common diseases affecting various crops. Because the diseases often occur below the soil layer and in the later stages of crop production, they are difficult to detect. Once plants show symptoms, it indicates that the pest or disease infestation is already quite severe, causing irreversible damage. Currently, the control of soil-borne pests and diseases mainly relies on chemical control, with the main forms of application being foliar spraying, root and stem spraying, and direct soil application. These methods achieve control by directly killing the pests and diseases through contact. However, in the later stages of crop growth, due to the large height of the plants, direct application of pesticides is not easy. Direct soil application is not only cumbersome to operate, but pesticides are also absorbed into the plant through the roots, posing a risk to the safety of agricultural products and potentially causing environmental pollution. In recent years, direct straw return to the field, excessive application of chemical fertilizers, and unscientific farming practices have exacerbated soil-borne diseases and pests in field crops. Diseases such as root rot and sheath blight in wheat and corn, as well as pests like grubs and crickets, have become widespread and prevalent, posing serious threats to grain production. Therefore, low-toxicity, low-damage, and highly efficient green methods for controlling soil-borne diseases and pests have become crucial for improving the quality and efficiency of modern agricultural production and ensuring stable food security.

[0003] Bacteria, fungi, insects, and insect eggs that cause crop diseases and pests have limited temperature tolerance. Temperatures of 50–60℃ can denature their proteins, achieving a disinfecting effect. Temperatures of 70–80℃ can completely eradicate diseases, pests, and eggs within a short time. Maintaining high soil temperatures for a certain period can effectively kill soil-borne diseases and pests, thus controlling them in crops. Simultaneously, crop stubble and straw carrying numerous pathogenic microorganisms, insect eggs, and weed seeds can be thoroughly eliminated through high-temperature treatment and burning, thereby reducing the amount of pathogenic microorganisms and pests at the source.

[0004] After crop harvest, a large amount of crop straw and stubble remains in the field, carrying a certain amount of crop pathogens, insect eggs, and weed seeds. Burning these straws and stubble can heat the soil and stubble with the high temperature generated during combustion, which can not only directly kill crop pathogens, but also improve the soil ecological environment through pyrolysis and carbonization.

[0005] Based on the above, this application proposes a method and device for controlling soil-borne diseases by heating the soil with high-temperature flue gas generated from burning straw and stubble. Summary of the Invention

[0006] The purpose of this invention is to provide a method and apparatus for preventing soil-borne diseases by burning straw and stubble to overcome the shortcomings of existing technologies.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A method for controlling soil-borne diseases by burning straw and stubble includes the following steps:

[0009] S1. Dig multiple smoldering trenches in an array in the farmland, fill the smoldering trenches with crop stubble and / or straw, install a perforated cover plate on the upper side of the smoldering trenches, and cover the perforated cover plate with a layer of crop stubble and / or straw and a layer of soil in sequence, then cover several of the smoldering trenches with an arched shed to form a sealed space, and set a flue and a flue at both ends of the smoldering trenches;

[0010] S2. On the outside of the arched shed, crop stubble and / or straw are burned, and the high-temperature flue gas generated by the combustion is introduced into the smoldering trench through the flue to warm the surrounding soil, and then discharged from the flue.

[0011] S3. After the temperature in the smoldering trench reaches the set value T1 and the temperature of the soil layer between the two adjacent smoldering trenches reaches the set value T2, stop introducing high-temperature flue gas into the smoldering trench, then ignite the crop stubble and / or straw in the smoldering trench, adjust the ventilation volume, and after the stubble and straw have smoldered for a set time S1, seal the flue gas inlet and outlet, and after heat preservation for a set time S2, complete the eradication of soil-borne diseases.

[0012] Preferably, the depth of the smoldering trench in step S1 is 20-25cm, the width is 25-30cm, and the distance between two adjacent smoldering trenches is 25-30cm; the height of the crop stubble and / or straw filling in the smoldering trench is 15-20cm.

[0013] The crop stubble and / or straw layer covering the porous cover plate is 3-5 cm high, and the soil layer covering it is 4-6 cm high.

[0014] The highest point of the arched shed is 50-60cm high.

[0015] Preferably, in step S3, T1 is 90-100℃, T2 is 75-80℃, and the T2 temperature is the soil temperature at a distance of 4-6cm between the surface layer of the two adjacent smoldering ditches.

[0016] S1 is 1 to 2 hours; S2 is 4 to 5 hours.

[0017] A device for preventing soil-borne diseases by burning straw and stubble includes multiple smoldering ditches dug in farmland and a combustion furnace;

[0018] The smoldering trench is filled with crop stubble and / or straw. A perforated cover plate is provided on the upper side of the smoldering trench, and a layer of crop stubble and / or straw and a layer of soil are sequentially covered on the perforated cover plate. An arched shed for forming a sealed space is provided above the soil covering of several of the smoldering trenches. A flue and an exhaust duct are provided at both ends of the smoldering trench.

[0019] The combustion furnace is located outside the arched shed and is used to burn crop stubble and / or straw to generate high-temperature flue gas. The combustion furnace is provided with a flue outlet that communicates with the flue inlet. The high-temperature flue gas can be transported through the flue outlet and the flue inlet to the smoldering ditch to heat the soil in the smoldering ditch and between two adjacent smoldering ditches.

[0020] Preferably, the inlet flue is provided with a first regulating damper, and the outlet flue is provided with a second regulating damper.

[0021] Preferably, the combustion furnace includes a hopper and a furnace chamber from top to bottom, and the hopper is provided with a discharge port at the bottom;

[0022] The furnace chamber is equipped with a grate, which is located below the discharge port of the hopper; the smoke outlet is located at the bottom of the furnace chamber.

[0023] The furnace shell includes an inner wall and an outer wall. Between the inner wall and the outer wall is a sandwich layer with openings at both the upper and lower ends. The lower opening of the sandwich layer is an air inlet. There is a gap between the inner wall and the outlet of the hopper. The outer wall extends to the outside of the hopper shell and forms a seal.

[0024] The furnace air enters the jacket from the lower opening and is preheated. Then, it enters the grate from the upper opening of the jacket and the gap between the inner wall and the material outlet of the hopper to mix and burn with the material. The high-temperature flue gas generated by combustion enters the flue gas inlet through the flue gas outlet and then enters the smoldering trough.

[0025] Preferably, the furnace chamber below the grate is a gradually tapering cone shape;

[0026] The outer wall of the furnace includes an inclined section at the bottom and a vertical section at the top, and support legs for supporting the furnace and the hopper are connected to the vertical section.

[0027] Preferably, an emergency water tank with a water outlet valve is provided outside the arched shed;

[0028] An emergency water hose is installed in the middle of the smoldering ditch inside the arched shed, and multiple water outlets are provided on the emergency water hose along the laying direction; the water inlet of the emergency water hose is connected to the water outlet valve.

[0029] The arched shed is equipped with a soil temperature sensor, which is electrically connected to the water outlet valve. When the soil temperature detected by the soil temperature sensor reaches the set value, the water outlet valve is automatically opened.

[0030] Preferably, the flue is also connected in sequence to a flue gas purification duct, an induced draft fan, and a chimney.

[0031] Preferably, the flue gas purification duct is filled with crushed straw and / or stubble, the length of which is 3-5 cm.

[0032] This application provides a method for controlling soil-borne diseases by utilizing high-temperature flue gas from burning straw stubble, smoldering straw stubble, and solar energy to heat the soil. This method is a physical control approach that fully utilizes farmland resources, reducing energy consumption by taking full advantage of the abundant crop straw stubble resources in farmland, thus achieving the goal of green pest control in agricultural production. Moreover, this method has minimal environmental impact and is easy to operate, providing a new method and technical approach for pest and disease control in my country's agricultural production. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of the device provided by the present invention;

[0034] Figure 2 This is a schematic diagram of the combustion furnace provided by the present invention.

[0035] Among them, 1-combustion furnace; 11-housing hopper; 12-housing hopper cover; 13-discharge port; 14-furnace chamber; 15-grate; 16-smoke outlet; 17-interlayer; 18-support leg; 19-outer wall; 2-smoldering trench; 21-perforated cover; 22-stubble, straw and soil covering layer; 23-soil temperature sensor; 24-smoke inlet; 25-smoke outlet; 26-first regulating damper; 27-second regulating damper; 28-smoke temperature sensor; 3-arched canopy; 41-emergency water tank; 42-emergency water hose; 5-flue gas purification duct; 6-induced draft fan; 7-chimney. Detailed Implementation

[0036] This invention provides a method for controlling soil-borne diseases by burning straw and stubble, comprising the following steps:

[0037] S1. Dig multiple smoldering trenches in an array in the farmland. Fill the trenches with crop stubble and / or straw (stubble and straw can be used alone or in combination). Install perforated covers on the upper side of the trenches, and then cover the perforated covers with a layer of crop stubble and / or straw, followed by a layer of soil. Then, cover several trenches with arched sheds to form a sealed space. Install inlet and outlet flues at both ends of the trenches. The arched sheds are preferably made of PVC solar film or polycarbonate panels. The highest point of the arched shed is 50-60cm high. While forming a sealed space to facilitate soil warming, solar energy can also be used to further heat the soil.

[0038] S2. On the outside of the arched greenhouse, crop stubble and / or straw are burned. The high-temperature flue gas generated from the combustion is introduced into the smoldering trench through the flue to warm and maintain the soil temperature. On the other hand, the stubble and straw in the smoldering trench are dried, which is beneficial for subsequent combustion. At the same time, the stubble and straw can also absorb and purify the flue gas before it is discharged from the flue. The straw covering the perforated cover plate can prevent the soil covering the upper layer from leaking into the smoldering trench through the holes of the cover plate, which would cause a large amount of flue gas to overflow. At the same time, the loose structure of the straw helps the flue gas flow and diffuse, increasing the heat diffusion rate. The soil covering the upper layer mainly forms an isolation, preventing the flue gas from directly entering the enclosed space below the arched greenhouse, and can isolate heat to avoid damage to the arched greenhouse.

[0039] S3. By adjusting the flow rate of high-temperature flue gas, a certain temperature can be maintained in the smoldering trench. As the temperature in the smoldering trench rises, the heat is transferred to both sides through the soil, and the soil temperature between two adjacent smoldering trenches also rises. After the temperature in the smoldering trench reaches the set value T1 and the temperature of the soil layer between two adjacent smoldering trenches (more specifically, the temperature of the soil layer 4-6 cm away from the surface between two adjacent smoldering trenches) reaches the set value T2, the flow of high-temperature flue gas into the smoldering trench is stopped. Then, the crop stubble and / or straw in the smoldering trench are ignited. The ventilation rate is adjusted to allow the stubble and straw to smolder (i.e., slow burning without flame) for a set time S1. After this time, the flue gas inlet and outlet are sealed, and the temperature is maintained for a set time S2, thus completing the eradication of soil-borne diseases. When the straw in the smoldering trench is smoldering, a small amount of straw on the perforated cover may also burn. Since it is covered with soil, no open flame will be produced inside the greenhouse.

[0040] The ash from burning on the outside of the arched shed contains certain inorganic nutrients, and it is preferable to return it to the field to increase the soil nutrient content.

[0041] After treating the soil with high temperatures, the damage to beneficial microorganisms caused by the high-temperature treatment can be effectively compensated by targeted supplementation of beneficial microorganisms, thus restoring normal ecological conditions to the soil.

[0042] After crop harvest, a large amount of crop straw and stubble remains in the field, carrying a certain amount of crop pathogens, insect eggs, and weed seeds. Utilizing the high temperature generated by burning crop straw to heat the soil and stubble not only directly kills crop pathogens, but the pyrolysis and carbonization of the straw and stubble also positively promotes the improvement of the soil's ecological environment. This application first uses the high-temperature flue gas generated by burning outside a greenhouse to heat and dry the straw and stubble filling the smoldering trench, initially raising the temperature of the soil in and around the trench. Then, the dried straw and stubble in the smoldering trench are ignited and allowed to burn slowly without flame, further raising the temperature of the soil in and around the trench. The greenhouse creates a closed space, which not only maintains a high soil temperature and retains heat, but also reduces water loss due to evaporation when the soil is heated, maintaining a high-temperature, high-humidity, and highly efficient sterilization state. Simultaneously, it fully utilizes daytime solar energy resources, further increasing soil temperature through the greenhouse effect created by the greenhouse, reducing straw consumption and shortening the soil sterilization time.

[0043] Therefore, this application provides a method for controlling soil-borne diseases by utilizing high-temperature flue gas from burning straw stubble, smoldering straw stubble, and solar energy to heat the soil. This method is a physical control method that fully utilizes farmland resources, reducing energy consumption by making full use of the abundant crop straw stubble resources in farmland, and achieving the goal of green pest control in agricultural production. This method has minimal environmental impact, is easy to operate, and can provide a new method and technical approach for pest and disease control in my country's agricultural production.

[0044] The size and spacing of the smoldering trenches should be appropriate to ensure suitable soil temperature within and between adjacent trenches. Preferably, the depth of the smoldering trenches is 20–25 cm, the width is 25–30 cm, and the distance between two adjacent smoldering trenches is 25–30 cm. The height of crop stubble and / or straw filling the smoldering trenches is 15–20 cm. The height of the crop stubble and / or straw layer covering the perforated cover plate is 3–5 cm, and the height of the soil layer covering it is 4–6 cm.

[0045] Preferably, the temperature T1 is 90-100℃, T2 is 75-80℃, S1 is 1-2h, and S2 is 4-5h. Within this temperature and time range, harmful microorganisms, pests, and insect eggs in the soil inside and between the smoldering trenches can be effectively killed, while the temperature is not too high and may easily cause a fire.

[0046] This application also provides an apparatus suitable for the above-described method, such as... Figure 1 As shown, it includes multiple smoldering trenches 2 excavated in the farmland and a combustion furnace 1.

[0047] The smoldering ditch 2 is a place where crop stubble and straw smolder and slowly release heat to heat the soil. It is filled with crop stubble and / or straw, and the surface of the smoldering ditch is provided with a perforated cover plate 21. A layer of crop stubble and / or straw and a layer of soil are sequentially covered on the perforated cover plate (see reference). Figure 1 The system consists of a stubble layer, straw, and soil covering (22). An arched shed (3) is installed above the soil covering of several smoldering trenches. The arched shed (3) serves to insulate, retain moisture, and increase the temperature of the soil blocks to be treated. The arched membrane is preferably made of PVC solar film or polycarbonate sheet, with a maximum height of 50-60 cm. The arched shed covers several groups of smoldering trenches to form a sealed space. At both ends of the smoldering trenches, there are inlet ducts (24) and outlet ducts (25) for the entry and exit of flue gas. The inlet and outlet ducts are preferably located outside the arched shed to facilitate control of the flue gas flow, ensuring that the temperature of each smoldering trench is as uniform as possible, avoiding short circuits that could cause excessively high local temperatures or blocked flue gas flow in a particular smoldering trench. This also facilitates ignition operations during the smoldering stage.

[0048] The combustion furnace 1 is located outside the arched shed 3 and is used to burn crop stubble and / or straw to generate high-temperature flue gas. The combustion furnace is equipped with a flue outlet 16 that is connected to the flue gas inlet.

[0049] The high-temperature flue gas generated by burning straw and stubble in the combustion furnace can be transported through the flue outlet 16 and the flue inlet 24 to the smoldering ditch 2 to heat the soil in the smoldering ditch and between two adjacent smoldering ditches, and to dry the straw and stubble in the smoldering ditch. At the same time, the straw and stubble also adsorb and purify the flue gas before it is discharged from the flue outlet. When the temperature in the smoldering ditch reaches the set value T1 and the temperature of the soil layer between two adjacent smoldering ditches reaches the set value T2, the combustion furnace is stopped. Then, the crop stubble and / or straw in the smoldering ditch are ignited at one end of the flue inlet. The ventilation is adjusted to allow the stubble and straw to smolder (i.e., slow burning without flame) for a set time S1. After that, the flue inlet and outlet are closed and the temperature is maintained for a set time S2, thus completing the eradication of soil-borne diseases.

[0050] As mentioned above, preferably, the depth of the smoldering trench is 20-25cm, the width is 25-30cm, and the distance between two adjacent smoldering trenches is 25-30cm; the filling height of crop stubble and / or straw in the smoldering trench is 15-20cm; the crop stubble and / or straw layer covering the perforated cover plate is 3-5cm high, and the covering soil layer is 4-6cm high.

[0051] Preferably, the temperature T1 is 90-100℃, T2 is 75-80℃, S1 is 1-2h, and S2 is 4-5h.

[0052] Preferably, a first regulating damper 26 is provided on the flue duct 24, and a second regulating damper 27 is provided on the flue duct 25. By regulating the dampers, the input volume of high-temperature flue gas and the air volume can be adjusted. Specifically, when the combustion furnace is burning, by adjusting the input volume of high-temperature flue gas, the soil in the smoldering ditch and between adjacent smoldering ditches can be kept at a set temperature. When the straw and stubble in the smoldering ditch are ignited, the first regulating damper and the second regulating damper can be adjusted to maintain a small ventilation volume so that the straw and stubble can be kept burning in a smoldering state.

[0053] The combustion furnace can adopt any existing structure, preferably, such as Figure 2 As shown, the combustion furnace 1 includes a hopper 11 and a furnace chamber 14 from top to bottom. The hopper 11 has a discharge port 13 at the bottom and a hopper cover plate 12 at the top.

[0054] The furnace chamber 14 is equipped with a grate 15, which is located below the material outlet 13 of the hopper; the flue gas outlet 16 is located at the bottom of the furnace chamber 14, and is connected to and sealed with the flue gas inlet 24.

[0055] The furnace shell includes an inner wall and an outer wall 19. Between the inner wall and the outer wall is a sandwich layer 17 with openings at both the upper and lower ends. The lower opening of the sandwich layer is an air inlet. There is a gap between the inner wall and the discharge port of the hopper. The outer wall 19 extends to the outside of the shell of the hopper 11 and forms a seal.

[0056] The air supply enters the jacket 17 from the lower opening of the jacket. Due to the high combustion temperature inside the furnace, the air supply temperature is increased, which is beneficial to the complete combustion of materials (especially for damp materials, the evaporation of moisture during combustion will take away some heat, causing the combustion environment temperature to drop and resulting in flameout. The increased air supply temperature can prevent flameout). At the same time, the air supply also absorbs heat from the inner wall to avoid high furnace temperature. Then it escapes from the upper opening of the jacket. Due to the obstruction of the outer wall and the hopper shell, it enters the grate 15 from the gap between the inner wall and the hopper outlet to mix and burn with the materials. The high-temperature flue gas generated by combustion enters the flue gas inlet through the flue gas outlet and then enters the smoldering ditch. On the one hand, it heats the straw, stubble and surrounding soil in the smoldering ditch. On the other hand, it uses the soil on the side wall of the smoldering ditch and the straw, stubble to purify the flue gas. The purified flue gas is discharged through the flue gas outlet.

[0057] When the treatment area of ​​the arched furnace is small and the amount of ash generated by combustion is small, an ash outlet may not be required. The ash will fall directly into the lower flue through the smoke outlet and be returned to the field after the soil heating task is completed. When the combustion furnace is continuously burning or the treatment area of ​​the arched furnace is large, it is preferable to set an ash outlet at the bottom of the furnace to prevent excessive accumulation of ash from affecting normal smoke output.

[0058] In traditional combustion furnaces, fuel is added from the side. As combustion occurs, a pusher device on the grate pushes the material horizontally, resulting in high-temperature flue gas rising and combustion ash descending. However, in this application, the flue gas inlet is underground. Therefore, if a traditional combustion furnace structure is used, the high-temperature flue gas must bend before entering the inlet, increasing the number of high-temperature flue gas pipes and making them more prone to hazard, while also complicating the device structure. Furthermore, in traditional combustion furnaces, ash accumulates on the upper side of the grate after combustion, and since the high-temperature flue gas rises, the high-temperature zone is also on the upper side of the grate, easily causing slagging and affecting combustion. This application uses a reverse combustion structure, where high-temperature flue gas descends directly into the inlet, effectively avoiding slagging. Simultaneously, the ash also descends after combustion, eliminating the need to consider ash discharge. Additionally, the fuel bin is located above the grate; straw and stubble materials placed on the grate automatically move downwards under gravity during combustion, eliminating the need for further pushing.

[0059] Therefore, the combustion furnace of this application adopts a reverse combustion structure, and the high-temperature flue gas is discharged from the bottom, which effectively avoids the problems of material pushing and slagging in traditional combustion furnaces. Moreover, it cleverly utilizes the furnace shell jacket to preheat the furnace air distribution, so that the material is fully combusted.

[0060] Preferably, the furnace chamber 14 below the grate is a tapered shape that gradually narrows; the outer wall of the furnace chamber includes an inclined section at the bottom and a vertical section at the top, and the support legs 18 for supporting the furnace chamber and the hopper are connected to the vertical section, and more preferably the support legs are connected to the vertical section by welding.

[0061] To prevent the straw and stubble in the smoldering ditch from burning open flames and causing damage to the arched film, thus endangering field safety, preferably, an emergency water tank 41 with a water outlet valve is installed outside the arched shed; an emergency water hose 42 is installed in the middle of the smoldering ditch inside the arched shed, with multiple water outlets along the laying direction on the emergency water hose; the water inlet end of the emergency water hose is connected to the water outlet valve.

[0062] Soil temperature sensors 23 are installed inside the arched shed. There are multiple soil temperature sensors installed in different locations inside the arched shed, including at least one in the smoldering ditch and one in the soil layer between two adjacent smoldering ditches.

[0063] Soil temperature sensor 23 is electrically connected to the water outlet valve. When the soil temperature detected by the soil temperature sensor reaches the set value, the water outlet valve is automatically opened to cool the soil. Preferably, the water outlet valve is automatically opened when the soil temperature sensor covering the upper side of the smoldering ditch exceeds 150°C to avoid open flames and potential hazards.

[0064] Preferably, a flue gas temperature sensor 28 is also provided at the flue gas outlet to detect the flue gas temperature, so as to facilitate the adjustment of the size of the second regulating damper 27. When the flue gas temperature is too high, the second regulating damper can be reduced to prolong the residence time of the high-temperature flue gas in the combustion trough. Conversely, when the flue gas temperature is too low, the second regulating damper can be increased.

[0065] Preferably, the flue gas outlet is also connected in sequence to a flue gas purification duct 5, an induced draft fan 6, and a chimney 7. The induced draft fan facilitates the flow of flue gas and air distribution. The flue gas, which has been cooled and initially purified by the combustion trough, undergoes further deep purification in the flue gas purification duct before being discharged from the chimney behind the fan.

[0066] In a further preferred embodiment, the flue gas purification duct 5 is filled with straw and / or stubble, which can not only purify the flue gas, but also provide an abundant source. After the soil heating is completed, the straw and / or stubble can be left in the flue gas purification duct and directly returned to the field for treatment.

[0067] To facilitate smoldering and fully absorb and purify flue gas, the straw and / or stubble covering the smoldering trench, flue gas purification channel, and porous cover plate can be crushed before filling. The length of the crushed straw and / or stubble should be about 3-5 cm.

[0068] In use, the device employs solar energy to heat the soil through an arched shed. Simultaneously, the high-temperature flue gas generated from the combustion of straw in the furnace is introduced into the smoldering ditch. This process both warms and maintains the soil temperature and dries the stubble and straw in the smoldering ditch, which also absorbs and purifies the flue gas. The amount of flue gas entering the smoldering ditch is adjusted by regulating the dampers to maintain the temperature within the ditch at 90–100°C. The flue gas, cooled and initially purified by the smoldering ditch, undergoes further deep purification in the flue gas purification duct before being discharged by the induced draft fan and chimney. The heat in the smoldering ditch is transferred to both sides through the soil until the temperature of the soil layer 5cm above the surface at the center of two adjacent smoldering ditches reaches 75–80°C. The furnace is then shut down, and the stubble or straw in the smoldering ditch is ignited at one end of the flue gas inlet. The dampers are adjusted to maintain a small ventilation volume, allowing the stubble and straw to smolder for 1–2 hours. After this, the induced draft fan is turned off, and the flue gas inlet and outlet are sealed. After maintaining the temperature for 4–5 hours, the control of soil-borne diseases is completed. During the operation of the device, the soil temperature sensor detects the surface temperature. When the surface temperature exceeds 150°C, the water outlet valve is automatically opened to spray water for cooling, preventing the straw and stubble in the smoldering ditch from burning open flames, which could damage the arched film and endanger field safety.

[0069] The method and apparatus provided in this application can be used not only in open fields, but also in greenhouses, indoor cultivation, and other similar settings. Furthermore, it can be implemented using a single combustion furnace for a single arched greenhouse or multiple arched greenhouses connected to a single combustion furnace. Other fuels can also be filled into the smoldering trench and used in the combustion furnace.

[0070] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A method for controlling soil-borne diseases by burning of straw and root stubble, characterized by, It comprises the following steps: S1. Excavating a plurality of smoldering trenches in an array in a farmland, filling the smoldering trenches with crop root stubble and / or straw, arranging a plurality of porous cover plates on the upper side of the smoldering trenches, and sequentially covering a layer of crop root stubble and / or straw and a layer of soil on the porous cover plates, then covering a plurality of the smoldering trenches with a canopy to form a sealed space, and arranging a smoke inlet and a smoke outlet at both ends of the smoldering trenches; S2. Burning crop root stubble and / or straw outside the canopy, passing the high-temperature flue gas generated by the burning into the smoldering trenches through the smoke inlet to warm the surrounding soil, and then discharging from the smoke outlet; S3. After the temperature in the smoldering trenches reaches a set value T1 and the temperature of the soil layer between two adjacent smoldering trenches reaches a set value T2, stop passing high-temperature flue gas into the smoldering trenches, then ignite the crop root stubble and / or straw in the smoldering trenches, adjust the ventilation volume, make the root stubble and straw smolder for a set time S1, then close the smoke inlet and the smoke outlet, and after a set heat preservation time S2, complete the killing of soil-borne diseases.

2. The method for preventing and treating soil-borne diseases by burning crop root stubble and / or straw according to claim 1, wherein the depth of the smoldering trench in step S1 is 20-25 cm, the width is 25-30 cm, and the distance between two adjacent smoldering trenches is 25-30 cm; the filling height of the crop root stubble and / or straw in the smoldering trench is 15-20 cm. The height of the layer of crop root stubble and / or straw covered on the porous cover plate is 3-5 cm, and the height of the layer of soil covered is 4-6 cm. The height of the highest point of the canopy is 50-60 cm.

3. The method for preventing and treating soil-borne diseases by burning crop root stubble and / or straw according to claim 1, wherein the T1 in step S3 is 90-100℃, the T2 is 75-80℃, and the T2 temperature is the temperature of the soil layer 4-6 cm away from the surface between two adjacent smoldering trenches; The set time S1 is 1-2 h, and the set time S2 is 4-5 h. ​ ​

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