Organic fertilizer anti-deterioration storage device and method for inhibiting secondary fermentation

Abstract

The application discloses an organic fertilizer anti-deterioration storage device and method for inhibiting secondary fermentation, and relates to the technical field of organic fertilizer storage and preservation. The device comprises a temperature control on-off valve, a gas circulation loop, an exhaust pipe, a condensate water separator, a return gas pipe and a stack body. The gas circulation loop is connected with the condensate water separator inlet through the exhaust pipe, and the condensate water separator outlet is connected to the bottom of the stack body through the return gas pipe. The temperature control on-off valve is arranged on the upstream of the exhaust pipe or the condensate water separator. The valve is actuated by a shape memory alloy driving element. The action temperature of the shape memory alloy driving element is set as a critical temperature for inhibiting secondary fermentation. The application automatically starts and stops the gas circulation regulation process according to the temperature change of the stack body. When the stack body appears a secondary fermentation temperature rising trend, the loop is started to quickly discharge the hot and humid gas in the stack body. The material is cooled and dehumidified through condensation and dehumidification. The carbon dioxide gas generated by fermentation is used to replace the oxygen in the stack body, so that a low-oxygen and high-carbon-dioxide inhibiting environment is formed in the stack body, the microbial activity is inhibited from the source, and the secondary fermentation reaction is blocked.

Description

Technical Field

[0001] This invention relates to the field of organic fertilizer storage and preservation technology, and in particular to an organic fertilizer storage device and method for inhibiting secondary fermentation and preventing spoilage. Background Technology

[0002] After the initial fermentation and maturation of organic fertilizer, a large number of microorganisms and incompletely decomposed organic matter still remain inside the material. During conventional storage and stacking, fluctuations in ambient temperature and residual oxygen inside the material continuously activate microbial activity, triggering a secondary fermentation reaction in the organic fertilizer. This secondary fermentation process continuously releases heat and moisture, further increasing the temperature and humidity of the organic fertilizer pile, creating a high-temperature, high-humidity fermentation environment that accelerates microbial reproduction and causes continuous decomposition and loss of organic matter.

[0003] Traditional methods of storing organic fertilizer often involve open-air piling, simple sealed storage, or ventilated drying. Open-air piling is susceptible to external rain, temperature, and air, leading to severe secondary fermentation and making the organic fertilizer prone to mold, clumping, and nutrient loss. Conventional sealed storage only provides basic oxygen and dust prevention, failing to remove the heat and moisture generated during fermentation within the pile. This results in a continuous increase in internal temperature and humidity, making it difficult to stop the secondary fermentation process and causing poor storage stability. While ventilated drying can reduce humidity, it continuously introduces external oxygen, further promoting microbial fermentation and causing the loss of available nutrients through volatilization.

[0004] Existing organic fertilizer storage technologies lack targeted mechanisms for inhibiting and regulating secondary fermentation. They cannot achieve adaptive regulation based on the fermentation temperature of the compost pile, and it is difficult to simultaneously achieve stable storage conditions with temperature control, dehumidification, and oxygen isolation. This results in short storage cycles and rapid quality degradation of organic fertilizers, significantly reducing the effectiveness of organic fertilizer application and the added value of products, and failing to meet the production needs of large-scale, long-term storage and preservation. Summary of the Invention

[0005] To solve the above-mentioned technical problems, this invention provides a device and method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation. The technical solution is as follows: A method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation includes the following steps: Step 1: Pile the organic fertilizer that has completed the initial fermentation into an airtight storage container, and set up a gas collection hood inside or above the pile. Step 2: Construct an airflow circulation loop including a temperature-controlled on / off valve. The loop connects the gas collection hood to the inlet of the condensate separator through the exhaust pipe. The outlet of the condensate separator is connected to the bottom of the pile through the return gas pipe. The temperature-controlled on / off valve is located upstream of the exhaust pipe or the condensate separator. The valve disc is actuated by a shape memory alloy actuator. The operating temperature of the shape memory alloy actuator is set to the critical temperature for inhibiting secondary fermentation. Step 3: When the temperature of the organic fertilizer pile rises to a level greater than or equal to the critical temperature due to secondary fermentation, the shape memory alloy drive component deforms to open the temperature control valve. The hot and humid gas generated in the pile enters the condensate separator through the exhaust pipe. The water vapor is condensed into liquid water and discharged. The remaining carbon dioxide-rich gas after cooling and dehumidification is injected from the bottom of the pile through the return gas pipe to form an air cushion layer that displaces upwards and blocks oxygen. Step 4: As carbon dioxide-rich gas is continuously injected, the oxygen concentration inside the stack gradually decreases, and the stack temperature drops due to dehumidification and heat dissipation. When the temperature drops to the set reset temperature, the shape memory alloy drive returns to its original shape, causing the temperature control valve to close, gas circulation stops, and the stack is stably stored under the inhibited state of low oxygen, high carbon dioxide, low temperature and low humidity.

[0006] Optionally, in step 2, the shape memory alloy driving component is a compression helical spring or a two-way shape memory alloy sheet, and the austenitic phase transformation end temperature is... Set to the critical temperature Similarly, the martensitic phase transformation initiation temperature Set as reset temperature And hysteresis interval Between 5℃ and 15℃ .

[0007] Optionally, in step 3, the condensate separator is equipped with multi-stage inclined baffles and heat dissipation fins, which utilize the natural convection of ambient air for cooling; the condensate is collected in the bottom water collection chamber and discharged through a water-sealed drainage device to prevent backflow of external air.

[0008] Optionally, in step 3, the end of the return gas pipe is connected to an annular porous gas distributor, which is laid flat at the bottom of the reactor body; a flow-limiting orifice plate is installed on the return gas pipe so that the reinjected carbon dioxide-rich gas is injected in a laminar flow state to avoid disturbing the reactor structure.

[0009] Optionally, when the ambient temperature is higher than a preset value, an auxiliary radiator containing phase change thermal storage material can be added upstream of the condensate separator. The phase change temperature of the phase change thermal storage material is lower than... The condensate separator is designed to meet the following condensation capacity requirements. , For condensing load, To maximize gas production mass flow rate, and These are the specific enthalpy of the gas at the inlet and outlet of the condensate separator, respectively. This represents the maximum heat generation rate of the secondary fermentation of the pile.

[0010] Optionally, in step 4, the oxygen concentration in the reactor core is reduced to below 5% by controlling the volume of injected carbon dioxide-rich gas, with the minimum required replacement volume... According to the formula Confirmed, among which The void volume of the stack. This represents the initial oxygen concentration. The target oxygen concentration.

[0011] An organic fertilizer storage device for inhibiting secondary fermentation and preventing spoilage is provided to implement a method for storing organic fertilizer for inhibiting secondary fermentation and preventing spoilage. The device includes an airtight storage container, a gas collection hood, a temperature-controlled valve, a condensate separator, a return gas pipe, and a drainage device. The airtight storage container is used to pile up organic fertilizer. The gas collection hood is installed above the pile and connected to the exhaust pipe. The temperature-controlled on / off valve is installed on the exhaust pipe and includes a valve body, valve disc and shape memory alloy drive component; the condensate separator inlet is connected to the temperature-controlled on / off valve outlet and has a condensation component inside. One end of the return pipe is connected to the outlet of the condensate separator, and the other end extends into the bottom of the airtight storage container and is connected to the annular porous gas distributor. The drainage device is connected to the water collection section of the condensate separator.

[0012] Optionally, the shape memory alloy drive component is a NiTi shape memory alloy spring, with one end fixed to the valve body and the other end fixed to the valve disc; when the ambient temperature reaches the austenite termination temperature... When the temperature drops to the martensitic initiation temperature, the spring extends and opens the valve disc; when the temperature drops to the martensitic initiation temperature... When the spring contracts, the valve disc closes.

[0013] Optionally, the condensate separator includes a vertical housing, downwardly inclined baffles arranged alternately inside the housing, vertical heat dissipation fins on the outside of the housing, and a bottom water collection hopper forming a drainage device through a U-shaped water seal pipe.

[0014] Optionally, the annular porous gas distributor is an annular porous tube with multiple outlet holes of 1mm-3mm in diameter at the lower part of the tube wall. The diameter of the annular porous tube is smaller than the inner diameter of the container, and the orifices face the bottom of the stack.

[0015] In summary, the present invention has at least one of the following beneficial technical effects: This invention provides a method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation. By constructing an adaptive temperature-controlled airflow circulation loop and utilizing the temperature response characteristics of shape memory alloys, precise and dynamic inhibition of secondary fermentation in organic fertilizer is achieved. The gas circulation control process can be automatically started and stopped according to changes in the pile temperature. When the pile shows a tendency to heat up due to secondary fermentation, the loop is automatically opened to quickly expel the hot and humid gas inside the pile. Cooling and dehumidifying the material is achieved through condensation, while carbon dioxide produced during fermentation replaces oxygen inside the pile, creating a low-oxygen, high-carbon dioxide inhibitory environment within the pile. This inhibits microbial activity at the source and completely blocks the secondary fermentation reaction. After the pile temperature drops back to a safe range, the device automatically closes the circulation loop, maintaining a stable low-temperature, low-humidity, and low-oxygen storage environment. No continuous manual control is required, demonstrating a high degree of automation.

[0016] Through a multi-stage baffle condensation and natural heat dissipation structure, water vapor separation of humid and hot gases can be efficiently achieved, preventing the material from becoming damp due to moisture backflow. Combined with a water-sealed drainage structure, it effectively prevents backflow of external air, ensuring the stability of the sealed storage environment. The bottom annular gas distribution structure allows for uniform laminar diffusion of carbon dioxide gas, preventing airflow disturbances from damaging the organic fertilizer compost pile structure, ensuring effective oxygen replacement throughout the entire pile, and achieving uniform preservation of freshness. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an organic fertilizer storage device for inhibiting secondary fermentation and preventing spoilage according to the present invention. Figure 2 yes Figure 1 Schematic diagram of the BB section; Figure 3 This is a three-dimensional structural diagram of an organic fertilizer storage device for inhibiting secondary fermentation and preventing spoilage, without the gas collection hood, according to the present invention. Figure 4 This is a schematic flowchart of a method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation according to the present invention.

[0018] Explanation of reference numerals in the attached drawings: 1. Airtight storage container; 3. Gas collection hood; 4. Temperature-controlled on / off valve; 5. Exhaust pipe; 6. Condensate separator; 7. Return gas pipe; 8. Annular perforated gas distributor. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings.

[0020] This invention discloses an organic fertilizer storage device and method for inhibiting secondary fermentation and preventing spoilage.

[0021] Reference Figures 1-4 Example 1: A method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation, comprising the following steps: Step 1: The organic fertilizer that has completed the initial fermentation is piled in an airtight storage container 1, and a gas collection hood 3 is set inside or above the pile. Step 2: Construct an airflow circulation loop including a temperature-controlled on / off valve 4. The loop connects the gas collection hood 3 to the inlet of the condensate separator 6 via the exhaust pipe 5. The outlet of the condensate separator 6 is connected to the bottom of the pile via the return gas pipe 7. The temperature-controlled on / off valve 4 is located upstream of the exhaust pipe 5 or the condensate separator 6. The valve disc is actuated by a shape memory alloy actuator. The operating temperature of the shape memory alloy actuator is set to the critical temperature for inhibiting secondary fermentation. Step 3: When the temperature of the organic fertilizer pile rises to a level greater than or equal to the critical temperature due to secondary fermentation, the shape memory alloy drive component deforms to open the temperature control valve 4. The hot and humid gas generated in the pile enters the condensate separator 6 through the exhaust pipe 5. The water vapor is condensed into liquid water and discharged. The remaining carbon dioxide-rich gas after cooling and dehumidification is injected from the bottom of the pile through the return gas pipe 7 to form an air cushion layer that displaces upwards and blocks oxygen. Step 4: As carbon dioxide-rich gas is continuously injected, the oxygen concentration inside the stack gradually decreases, and the stack temperature drops due to dehumidification and heat dissipation. When the temperature drops to the set reset temperature, the shape memory alloy drive returns to its original state, causing the temperature control valve 4 to close, gas circulation stops, and the stack is stably stored under the inhibited state of low oxygen, high carbon dioxide, low temperature and low humidity.

[0022] By adopting the above technical solution, the heat and carbon dioxide generated by the secondary fermentation of organic fertilizer are utilized to inhibit fermentation through passive adaptive controlled atmosphere circulation. In specific implementation, the organic fertilizer that has completed its primary fermentation is first piled in an airtight storage container 1 to form a pile, and a gas collection hood 3 is installed above the pile to collect the gas released from it. Then, an airflow circulation loop including a temperature-controlled on / off valve 4 is constructed: one end of the exhaust pipe 5 is connected to the gas collection hood 3, and the other end is connected to the inlet of the condensate separator 6 via the temperature-controlled on / off valve 4. The outlet of the condensate separator 6 extends to the bottom of the pile through a return gas pipe 7 and is connected to an annular porous gas distributor 8. The valve disc of the temperature-controlled on / off valve 4 is actuated by a shape memory alloy actuator, the operating temperature of which is preset to the critical temperature Tc for inhibiting secondary fermentation.

[0023] When organic fertilizer undergoes secondary fermentation due to the metabolism of residual microorganisms, the temperature of the compost pile gradually rises. Once the temperature reaches or exceeds the critical temperature... The shape memory alloy drive component undergoes a phase change and deforms, pushing the temperature-controlled on / off valve 4 to open. The slightly positive pressure hot and humid gases accumulated within the reactor core due to fermentation enter the condensate separator 6 through the gas collection hood 3 and exhaust pipe 5. These gases are rich in carbon dioxide and water vapor. In the condensate separator 6, the gases are cooled, the water vapor condenses into liquid water and is discharged through the drainage device, and the remaining gas becomes a cooled and dehumidified carbon dioxide-rich gas stream. This gas stream is transported to the bottom of the reactor core through the return gas pipe 7 and injected in a laminar flow manner through the annular porous gas distributor 8, forming a low-temperature, high-concentration carbon dioxide gas cushion layer at the bottom of the reactor core, displacing oxygen in the reactor core voids from bottom to top.

[0024] As carbon dioxide-rich gas is continuously injected, the oxygen concentration inside the reactor core gradually decreases. Simultaneously, heat is carried away by the gas flow and dissipated through condensation, causing the temperature to gradually drop. When the temperature decreases to the preset reset temperature... At this time, the shape memory alloy drive component undergoes another phase change to restore its original shape, causing the temperature control valve 4 to close, gas circulation to stop, and the reactor core to enter a suppressed state of low oxygen, high carbon dioxide, low temperature, and low humidity. Due to Below This creates a temperature hysteresis range for the switching mechanism, preventing frequent opening and closing of the valves. If the reactor temperature subsequently exceeds this range again... The above-mentioned ventilation and dehumidification process will be repeated to achieve long-term stable storage.

[0025] Example 2: In step 2, the shape memory alloy driving component is a compression helical spring or a two-way shape memory alloy sheet, and the austenitic phase transformation end temperature is... Set to the critical temperature Similarly, the martensitic phase transformation initiation temperature Set as reset temperature And hysteresis interval Between 5℃ and 15℃ .

[0026] By adopting the above technical solution, the shape memory alloy driving component is selected from a compression helical spring or a two-way shape memory alloy sheet, and its austenitic phase transformation end temperature is... Set to the critical temperature Similarly, the martensitic phase transformation initiation temperature Set to reset temperature Same. Hysteresis interval Depend on minus The value is determined to be between 5℃ and 15℃. When the reactor temperature rises to... At that time, the shape memory alloy actuator completes the austenitic phase transformation, generating driving force to open the valve; when the stack temperature drops to... At this time, the driving component returns to the martensitic state, and the valve closes. Because the temperature change caused by secondary fermentation is relatively slow, combined with... and The hysteresis characteristic ensures that the valve only opens when the temperature exceeds the limit and closes only after sufficient cooling, preventing repeated fluctuations around a single threshold, thus improving the system's operational stability and component lifespan.

[0027] In Example 3, the condensate separator 6 in step 3 is equipped with multi-stage inclined baffles and heat dissipation fins, which are cooled by natural convection of ambient air. The condensate is collected in the bottom water collection chamber and discharged through a water-sealed drainage device to prevent backflow of external air.

[0028] By adopting the above technical solution, the condensate separator 6 has multiple stages of downwardly inclined baffles arranged alternately inside its shell. Hot and humid gas flows along the tortuous channels formed by the baffles after entering, effectively increasing the gas residence time and heat exchange contact area. Vertical heat dissipation fins are installed on the outside of the shell, utilizing natural convection of ambient air to cool the shell without the need for an external fan. When high-temperature, high-humidity gas flows through the baffles, heat is dissipated to the outside through the plate walls and heat dissipation fins, lowering the gas temperature. Water vapor in the gas reaches a supersaturated state and condenses on the surface of the baffles. The condensate flows down the inclined plate surface and collects in the bottom water collection chamber. The drainage device uses a water seal; condensate is discharged through a U-shaped water seal pipe, using the accumulated water to form a liquid seal. While discharging liquid water, it prevents outside air from flowing back into the system from the drain outlet, maintaining the airtightness of the entire loop.

[0029] In Example 4, the end of the return gas pipe 7 in step 3 is connected to an annular porous gas distributor 8, which is laid flat at the bottom of the reactor body. A flow-limiting orifice plate is provided on the return gas pipe 7 so that the reinjected carbon dioxide-rich gas is injected in a laminar flow state to avoid disturbing the reactor structure.

[0030] By adopting the above technical solution, the end of the return gas pipe 7 is connected to an annular porous gas distributor 8, which is laid flat at the bottom of the reactor body. A flow-limiting orifice plate is installed on the return gas pipe 7 to control the flow rate of the reinjected gas. The carbon dioxide-rich gas, after condensation and dehumidification, enters the bottom of the reactor body uniformly at a low laminar flow velocity through multiple outlet holes on the annular porous gas distributor 8. This laminar flow injection method avoids disturbance to the reactor structure. Simultaneously, by utilizing the low temperature and high density characteristics of the carbon dioxide-rich gas, a stable air cushion layer is formed at the bottom of the reactor body, gradually pushing upwards to displace oxygen in the reactor body voids, achieving efficient oxygen displacement.

[0031] Example 5: When the ambient temperature is higher than a preset value, an auxiliary radiator containing phase change cold storage material is added upstream of the condensate separator 6. The phase change temperature of the phase change cold storage material is lower than... The condensate separator 6 is designed to meet the following condensation capacity requirements. , For condensing load, To maximize gas production mass flow rate, and These are the specific enthalpy of the gas at the inlet and outlet of the condensate separator 6, respectively. This represents the maximum heat generation rate of the secondary fermentation of the pile.

[0032] By adopting the above technical solution, when the ambient temperature is higher than the preset value, resulting in insufficient natural heat dissipation, an auxiliary radiator containing phase change thermal storage material is added upstream of the condensate separator 6. The phase change temperature of this phase change thermal storage material is selected to be lower than the reset temperature. It can pre-cool the hot and humid gas before it enters the condensate separator 6 through condensation and heat storage at night or when the temperature is low, and through melting and heat absorption during the high-temperature period of the day, thereby enhancing the subsequent condensation and dehumidification effect. At the same time, the condensate separator 6 must be designed with a condensation capacity that meets the requirements. ,and Greater than or equal to the maximum heat production rate of secondary fermentation in the pile ,in This represents the maximum gas production mass flow rate that secondary fermentation may generate. and These are the specific enthalpy of the gas at the inlet and outlet of the condensate separator 6, respectively. This relationship is used to determine the condensation area, ensuring that even under high fermentation intensity, all excess moisture in the produced gas can be fully condensed and precipitated, preventing moisture back-injection and subsequent reheating of the pile.

[0033] Example 6: In step 4, the oxygen concentration in the reactor core is reduced to below 5% by controlling the volume of injected carbon dioxide-rich gas. The minimum required replacement volume is... According to the formula Confirmed, among which The void volume of the stack. This represents the initial oxygen concentration. The target oxygen concentration.

[0034] By adopting the above technical solution, in order to reliably reduce the oxygen concentration in the reactor to below 5% required to inhibit secondary fermentation, it is necessary to control the volume of carbon dioxide-rich gas injected in each cycle. The minimum required replacement volume... From the formula Confirmed. In the formula, The void volume of the stack is obtained by multiplying the apparent volume of the stack by the porosity. This represents the initial oxygen concentration, typically taken as 21%. The target oxygen concentration is set at 5%. This formula is based on an ideal piston flow model of laminar gas cushion displacement, where the injected carbon dioxide-rich gas pushes oxygen out of the reactor body from bottom to top. When the injected volume reaches... At that time, the average oxygen concentration in the reactor core can be reduced to the target value. The effective gas circulation volume corresponding to the opening of the temperature-controlled valve 4 in a single operation should be designed to be no less than this. The value is adjusted to ensure the oxygen-suppressing effect.

[0035] Example 7: An organic fertilizer storage device for inhibiting secondary fermentation and preventing spoilage, used to implement a method for storing organic fertilizer for inhibiting secondary fermentation and preventing spoilage. The device includes an airtight storage container 1, a gas collection hood 3, a temperature-controlled on / off valve 4, a condensate separator 6, a return gas pipe 7, and a drainage device. The airtight storage container 1 is used to pile up organic fertilizer. The gas collection hood 3 is installed above the pile and connected to the exhaust pipe 5. The temperature-controlled valve 4 is installed on the exhaust pipe 5 and includes a valve body, a valve disc and a shape memory alloy drive component; the inlet of the condensate separator 6 is connected to the outlet of the temperature-controlled valve 4 and has a condensation component inside. One end of the return pipe 7 is connected to the outlet of the condensate separator 6, and the other end extends into the bottom of the airtight storage container 1 and is connected to the annular porous air distributor 8. The drainage device is connected to the water collection section of the condensate separator 6.

[0036] By adopting the above technical solution, the device includes an airtight storage container 1, which is used to store organic fertilizer. A gas collection hood 3 is installed above the pile and is connected to the inlet of a temperature-controlled valve 4 via an exhaust pipe 5. The temperature-controlled valve 4 is installed on the exhaust pipe 5 and consists of a valve body, a valve disc, and a shape memory alloy drive component. The outlet of the temperature-controlled valve 4 is connected to the inlet of a condensate separator 6, which has a condensation component inside. Its outlet is connected to one end of a return gas pipe 7. The other end of the return gas pipe 7 extends into the bottom of the airtight storage container 1 and is connected to an annular porous gas distributor 8. A drainage device is connected to the water collection section at the bottom of the condensate separator 6. The entire device forms a closed gas circulation loop without external power. When the pile temperature reaches the critical temperature, the shape memory alloy drive component automatically opens the valve, allowing the hot and humid gas to be condensed and dehydrated into a carbon dioxide-rich gas stream that is then injected back into the bottom of the pile, achieving controlled atmosphere desiccation and cooling. When the temperature drops back to the reset temperature, the valve closes, thus maintaining the low-metabolic storage state of the pile in a continuous cycle.

[0037] Example 8: The shape memory alloy drive component is a NiTi shape memory alloy spring, one end of which is fixed to the valve body, and the other end is fixed to the valve disc; when the ambient temperature reaches the austenite termination temperature... When the temperature drops to the martensitic initiation temperature, the spring extends and opens the valve disc; when the temperature drops to the martensitic initiation temperature... When the spring contracts, the valve disc closes.

[0038] By adopting the above technical solution, the shape memory alloy driving component specifically uses a compression helical spring made of NiTi shape memory alloy. One end of the spring is fixed to the valve body of the temperature control valve 4, and the other end is fixedly connected to the valve disc.

[0039] When the internal ambient temperature of the device rises to the austenite termination temperature At this time, the NiTi shape memory alloy spring undergoes a martensitic-to-austenitic phase transformation, resulting in axial elongation. This elongation overcomes the closing force of the valve disc, opening it and allowing the airflow channel to open. As the temperature gradually decreases to the martensitic initiation temperature... When the shape memory alloy spring contracts in reverse phase change, the valve disc resets and closes under its own gravity or the action of an auxiliary elastic element. This driving method is powered entirely by the material phase change induced by temperature change, realizing passive integration of sensing and driving.

[0040] Example 9: The condensate separator 6 includes a vertical shell, downwardly inclined baffles arranged alternately inside the shell, vertical heat dissipation fins on the outside of the shell, and a bottom water collection hopper forming a drainage device through a U-shaped water seal pipe.

[0041] By adopting the above technical solution, the condensate separator 6 includes a vertical shell with multiple levels of downward-sloping baffles arranged alternately from top to bottom inside the shell, forming an airflow channel with multiple turns. Vertical heat dissipation fins are arranged along the circumference of the shell exterior to enhance natural convection heat exchange with the surrounding air. When the high-temperature, high-humidity gas entering the condensate separator 6 flows between the baffles, heat is continuously lost through the shell and heat dissipation fins. The temperature drop causes water vapor to condense into liquid water on the surface of the baffles and flow along the baffle surface to the water collection hopper at the bottom of the shell. The outlet of the water collection hopper is connected to a U-shaped water seal pipe, which is part of the drainage device. Water is always present inside the pipe, forming a liquid seal, allowing the condensate to drain smoothly while blocking outside air, thus ensuring that the internal atmosphere of the system is not diluted by external air.

[0042] Example 10: The annular porous gas distributor 8 is an annular porous tube with multiple gas outlet holes of 1mm-3mm in diameter at the lower part of the tube wall. The diameter of the annular porous tube is smaller than the inner diameter of the container, and the orifices face the bottom of the stack.

[0043] By adopting the above technical solution, the annular porous gas distributor 8 is a closed annular porous tube with a diameter smaller than the inner diameter of the gas-tight storage container 1, and is laid horizontally at the bottom of the stack. Multiple outlet holes with diameters between 1mm and 3mm are opened on the lower part of the tube wall, and all outlet holes face the bottom of the stack. After the carbon dioxide-rich gas from the return gas pipe 7 enters the annular porous tube, it escapes evenly through the small holes, diffuses slowly along the bottom surface of the container, and seeps upwards into the bottom of the stack in a laminar flow state. This gas distribution structure and method can quickly form a continuous and stable carbon dioxide gas cushion layer at the bottom of the stack, achieving overall displacement of oxygen in the stack voids from bottom to top, avoiding local airflow short-circuiting, and improving gas replacement efficiency.

[0044] The following specific embodiments illustrate the implementation principle of the present invention: A company producing 5,000 tons of commercial organic fertilizer annually frequently experiences clumping, mold growth, and nitrogen loss due to secondary fermentation during summer storage of its powdered cow dung organic fertilizer. The following provides specific implementation examples of the proposed solution and traditional processes in this scenario.

[0045] The present invention proposes the following method: 10 tons of powdered cow manure organic fertilizer that has completed the first fermentation and whose moisture content has been reduced to 30% are selected and piled in an airtight storage container 1 with a volume of 15 cubic meters to form a pile. The measured porosity ε of the pile is 0.40.

[0046] Step 1: Install a conical gas collection hood 3 0.3 meters above the pile body, with the lower edge of the gas collection hood 3 covering the entire surface of the pile body.

[0047] Step 2: Construct the airflow circulation loop. The exhaust pipe 5 is a 50mm diameter stainless steel pipe, connected at one end to the top outlet of the gas collection hood 3 and at the other end to the inlet of the temperature-controlled on / off valve 4. The temperature-controlled on / off valve 4 uses a lift-type valve body, with the valve disc actuated by a shape memory alloy actuator. The shape memory alloy actuator is a NiTi shape memory alloy compression coil spring, with the austenitic phase transformation end temperature... The temperature is set at 48℃, which is the critical temperature. 48℃ is the temperature at which the martensitic phase transformation begins. Set to 38℃, which is the reset temperature. The temperature is 38℃, and the hysteresis interval ∆T is 10℃. The outlet of the temperature-controlled on / off valve 4 is connected to the inlet of the condensate separator 6.

[0048] The condensate separator 6 adopts a vertical shell with five alternating stages of downward-sloping baffles inside. Vertical heat dissipation fins are welded to the outside of the shell. A U-shaped water seal pipe connects to the bottom collection hopper of the condensate separator 6 to form a drainage device. The outlet of the condensate separator 6 is connected to a return gas pipe 7, the other end of which extends into the bottom of the airtight storage container 1 and connects to an annular porous gas distributor 8. The annular porous gas distributor 8 is a 2-meter diameter annular porous pipe with 40 2-millimeter diameter outlet holes on the lower part of the pipe wall, facing the bottom of the stack. A flow-limiting orifice plate with an 8-millimeter diameter is installed on the return gas pipe 7. The airtight storage container 1 is sealed with a sealing door.

[0049] Step 3: On the second day after the organic fertilizer is placed in the storage facility, the pile begins to generate heat due to secondary fermentation by residual microorganisms, and the pile temperature gradually rises from the initial 32℃. On the afternoon of the third day, the pile temperature reaches 48℃, which is the critical temperature. The shape memory alloy drive component completes the austenitic phase transformation, and the NiTi shape memory alloy spring extends axially, pushing the valve disc of the temperature control valve 4 to open.

[0050] Hot, humid gas with a slight positive pressure inside the reactor enters the condensate separator 6 through the gas collection hood 3 and the exhaust pipe 5. The gas temperature is approximately 50°C, the relative humidity is close to 100%, and the carbon dioxide concentration is approximately 18%. The hot, humid gas flows through the condensate separator 6, changing direction multiple times along the baffle plates. Heat is dissipated into the environment through the shell and heat dissipation fins, where the ambient air temperature is approximately 30°C. The gas temperature drops to approximately 32°C, and water vapor condenses on the surface of the baffle plates. The condensate flows along the plate surface to the bottom water collection hopper and is discharged through the U-shaped water seal pipe. Approximately 1.5 liters of condensate are discharged in a single cycle.

[0051] After cooling and dehumidification, the carbon dioxide-rich gas enters the annular porous gas distributor 8 in a laminar flow state through the return gas pipe 7 and the flow-limiting orifice plate, and is evenly injected into the bottom of the reactor body from the bottom outlet. The gas temperature is about 32°C and the density is relatively high. It spreads at the bottom of the reactor body to form a carbon dioxide gas cushion layer, which displaces the oxygen in the voids of the reactor body from bottom to top.

[0052] Step 4: As carbon dioxide-rich gas is continuously injected, the oxygen concentration inside the reactor gradually decreases from the initial 21%. Apparent volume of the reactor. =15m³, porosity ε=0.40, voluminous volume of the pile body = ×ε=6m³. Initial oxygen concentration =21%, target oxygen concentration =5%. The minimum required displacement volume according to the ideal piston flow displacement model. Calculate using the following formula: =6m³×ln(21% / 5%)≈6m³×1.435=8.m³; In this embodiment, the effective gas circulation volume corresponding to a single opening cycle of the temperature-controlled valve 4 is approximately 9 m³, which satisfies... Requirements: When the oxygen concentration inside the reactor core drops to 4.8%, the reactor core temperature has returned to the reset temperature. =38℃. The shape memory alloy actuator reaches the martensitic phase transformation initiation temperature. The NiTi shape memory alloy spring contracts, and the valve disc of the temperature-controlled on / off valve 4 resets and closes under gravity, stopping gas circulation. At this time, the reactor enters a suppressed state, with an internal oxygen concentration of 4.8%, a carbon dioxide concentration of approximately 16%, a temperature of 38°C, and a further reduction in moisture content due to condensation and dehumidification.

[0053] Over the following week, the reactor temperature fluctuated between 36°C and 39°C, and the critical temperature was not triggered again. Secondary fermentation was effectively suppressed. After 60 days of storage, the organic fertilizer was tested and found to be loose, without lumps or mold, and the total nitrogen content decreased by only 3.2%.

[0054] Comparative Example: Traditional Stacking and Storage Process Ten tons of powdered cow manure organic fertilizer, which had completed its initial fermentation and had a moisture content of 30%, were directly piled on the floor of an ordinary warehouse of the same area. The pile was about 1.5 meters high and covered with a plastic film to prevent rain and surface drying. However, there were no airtight measures, no ventilation or dehumidification equipment, and no controlled atmosphere treatment. The pile was turned manually once a week to dissipate heat and improve ventilation.

[0055] On the second day of storage, the internal temperature of the pile rose to 52℃, reaching its peak on the third day. A large amount of condensation appeared on the inner wall of the surface film, dripping back into the pile and causing localized increases in moisture content. A strong ammonia odor was emitted during turning the pile. After 15 days of storage, white mold spots and a grayish-green mold layer appeared inside the pile, with severe localized clumping, making it difficult to move. Sampling and testing after 30 days of storage showed that the total nitrogen content at the center of the pile had decreased by 18.5% compared to the initial level, the organic matter loss rate was 12.7%, and the moisture content had increased to a certain percentage due to metabolic water production and condensation reflux. After 60 days, the pile was opened; the product had turned black and smelled foul over a large area, losing its commercial value, with an overall scrap rate of approximately 35%.

[0056] To visually demonstrate the differences in storage performance between the present invention and traditional processes, key indicators such as storage temperature control, oxygen concentration, moisture management, nitrogen loss, product condition, and energy consumption were compared. The comparative data are based on the actual measurement results of the two implementation cases mentioned above, where the relevant parameters of the present invention are determined by the critical temperature set in step 2. Reset temperature The replacement volume calculation in step 4 is controlled by traditional process parameters, which are the monitoring values ​​under natural stacking conditions.

[0057] The technical effects are compared in Table 1: Table 1 As can be seen from the above comparison, the present invention, by setting the phase transition temperature of the shape memory alloy driving component, achieves an adaptive ventilation and dehumidification cycle driven by the secondary fermentation heat of the reactor core itself, without any external energy source or sensors. When the reactor core temperature reaches the critical temperature... At 48 ℃, the temperature control valve 4 automatically opens. After being dehumidified by the condensate separator 6, the hot and humid gas is reinjected as a carbon dioxide-rich gas stream from the bottom of the annular porous gas distributor 8, forming a carbon dioxide cushion layer to displace oxygen. This rapidly reduces the oxygen concentration in the reactor core to below 5%, while simultaneously removing excess moisture and heat, thus maintaining the reactor core temperature at the reset temperature. =Approximately 38℃. The hysteresis interval ∆T=10℃ ensures the intermittent stability of the cycle. Ultimately, the pile is in a state of suppression characterized by low oxygen, high carbon dioxide, low temperature, and low humidity for a long period, with a total nitrogen loss of only 3.2% and an organic matter loss of 2.1%, maintaining the product quality intact. Compared with traditional stacking processes, which suffer from runaway temperature, severe deterioration due to high oxygen and high humidity, and a 35% scrap rate, the present invention has significant advantages in nitrogen preservation, mold prevention, no need for turning the pile, and zero energy consumption, making it particularly suitable for the long-term safe storage of large quantities of commercial organic fertilizer.

[0058] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation, characterized in that: Includes the following steps: Step 1: The organic fertilizer that has completed the first fermentation is piled in an airtight storage container (1), and a gas collection hood (3) is set inside or above the pile. Step 2: Construct an airflow circulation loop including a temperature-controlled on / off valve (4). The loop connects the gas collection hood (3) to the inlet of the condensate separator (6) through the exhaust pipe (5). The outlet of the condensate separator (6) is connected to the bottom of the pile through the return gas pipe (7). The temperature-controlled on / off valve (4) is located upstream of the exhaust pipe (5) or the condensate separator (6). The valve disc is actuated by a shape memory alloy actuator. The operating temperature of the shape memory alloy actuator is set to the critical temperature for inhibiting secondary fermentation. Step 3: When the temperature of the organic fertilizer pile rises to a level greater than or equal to the critical temperature due to secondary fermentation, the shape memory alloy drive component deforms to open the temperature control valve (4). The hot and humid gas generated in the pile enters the condensate separator (6) through the exhaust pipe (5). The water vapor condenses into liquid water and is discharged. The remaining carbon dioxide-rich gas after cooling and dehumidification is injected from the bottom of the pile through the return gas pipe (7) to form an air cushion layer that displaces upwards and blocks oxygen. Step 4: As carbon dioxide-rich gas is continuously injected, the oxygen concentration inside the stack gradually decreases, and the stack temperature drops due to dehumidification and heat dissipation. When the temperature drops to the set reset temperature, the shape memory alloy drive returns to its original state, causing the temperature control valve (4) to close, the gas circulation stops, and the stack is stably stored under the inhibited state of low oxygen, high carbon dioxide, low temperature and low humidity.

2. The method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation according to claim 1, characterized in that: In step 2, the shape memory alloy driving component is a compression coil spring or a two-way shape memory alloy sheet, and the austenitic phase transformation end temperature is... Set to the critical temperature Similarly, the martensitic phase transformation initiation temperature Set as reset temperature And hysteresis interval Between 5℃ and 15℃ .

3. The method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation according to claim 2, characterized in that: In step 3, the condensate separator (6) is equipped with multi-stage inclined baffles and external heat dissipation fins, which utilize the natural convection of ambient air for cooling; the condensate is collected in the bottom water collection chamber and discharged through a water-sealed drainage device to prevent backflow of external air.

4. The method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation according to claim 3, characterized in that: In step 3, the end of the return gas pipe (7) is connected to the annular porous gas distributor (8), which is laid flat at the bottom of the stack. A flow-limiting orifice plate is installed on the return gas pipe (7) so that the carbon dioxide-rich gas is injected in a laminar flow state to avoid disturbing the stack structure.

5. A method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation according to claim 4, characterized in that: When the ambient temperature is higher than the preset value, an auxiliary radiator containing phase change cold storage material is added upstream of the condensate separator (6). The phase change temperature of the phase change cold storage material is lower than that of the phase change material. The condensate separator (6) is designed to meet the following condensation capacity requirements. , For condensing load, To maximize gas production mass flow rate, and These are the specific enthalpy of the gas at the inlet and outlet of the condensate separator (6), respectively. This represents the maximum heat generation rate of the secondary fermentation of the pile.

6. A method for storing organic fertilizer to prevent spoilage and inhibit secondary fermentation according to claim 5, characterized in that, In step 4, the oxygen concentration in the reactor is reduced to below 5% by controlling the volume of injected carbon dioxide-rich gas. The minimum replacement volume required is... According to the formula Confirmed, among which The void volume of the stack. This represents the initial oxygen concentration. The target oxygen concentration.

7. A storage device for organic fertilizer to inhibit secondary fermentation and prevent spoilage, characterized in that: To implement the method for storing organic fertilizer to prevent deterioration and inhibit secondary fermentation as described in claim 6, the device includes an airtight storage container (1), a gas collection hood (3), a temperature control valve (4), a condensate separator (6), a return gas pipe (7), and a drainage device. The airtight storage container (1) is used to pile up organic fertilizer. The gas collection hood (3) is installed above the pile and connected to the exhaust pipe (5). The temperature-controlled valve (4) is installed on the exhaust pipe (5) and includes a valve body, valve disc and shape memory alloy drive component; the air inlet of the condensate separator (6) is connected to the outlet of the temperature-controlled valve (4) and is equipped with a condensation component inside. One end of the return pipe (7) is connected to the outlet of the condensate separator (6), and the other end extends into the bottom of the airtight storage container (1) and is connected to the annular porous gas distributor (8). The drainage device is connected to the water collection section of the condensate separator (6).

8. The organic fertilizer storage device for inhibiting secondary fermentation and preventing spoilage according to claim 7, characterized in that, The shape memory alloy actuator is a NiTi shape memory alloy spring, with one end fixed to the valve body and the other end fixed to the valve disc; when the ambient temperature reaches the austenite termination temperature... When the temperature drops to the martensitic initiation temperature, the spring extends and opens the valve disc; when the temperature drops to the martensitic initiation temperature... When the spring contracts, the valve disc closes.

9. The organic fertilizer storage device for inhibiting secondary fermentation and preventing spoilage according to claim 8, characterized in that, The condensate separator (6) includes a vertical shell, downwardly inclined baffles arranged alternately inside the shell, vertical heat dissipation fins on the outside of the shell, and a bottom water collection hopper forming a drainage device through a U-shaped water seal pipe.

10. The organic fertilizer storage device for inhibiting secondary fermentation and preventing spoilage according to claim 9, characterized in that, The annular porous gas distributor (8) is an annular porous tube with multiple outlet holes of 1mm-3mm in diameter at the lower part of the tube wall. The diameter of the annular porous tube is smaller than the inner diameter of the container, and the orifice faces the bottom of the stack.

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