Heat release catalyst and perishable garbage chemical catalysis enhanced biological drying decomposition promoting process

Abstract

The invention discloses a heat release catalyst and a perishable garbage chemical catalysis enhanced biological drying decomposition promoting process. The manganese-cerium bimetallic loaded oxidation heat release catalyst is prepared by adopting an ultrasonic dispersion-two-step hydrothermal method. When the heat release catalyst is added into the perishable garbage biological drying process, material pores can be improved, oxygen can be promoted to be converted into active oxygen, organic matter is catalyzed and oxidized to generate a large amount of heat energy, temperature rise and organic matter decomposition in the biological drying humification process are promoted, efficient succession of thermophilic functional microorganisms is promoted, and the biological drying humification effect is improved. Therefore, the fertilizer forming period is shortened to 6-9 days, and the rotten fertilizer with the seed germination index as high as 90% is obtained. According to the method, the idea that traditional composting only depends on biological heat generated by microorganisms is broken through, chemical catalysis and microbial decomposition are combined, the bottleneck problems that heating dehydration is difficult in the starting stage, the decomposition period is long, the occupied area is large, and the fertilizer quality is low are effectively solved, and reference is provided for efficient and rapid fertilization of perishable garbage.

Description

Technical Field

[0001] The present invention belongs to the field of resource treatment of perishable waste, and particularly relates to a heat-releasing catalyst and a chemical catalytic enhanced biological drying and composting promotion process for perishable waste. Background Art

[0002] If various organic wastes such as municipal domestic waste and agricultural wastes (including crop straws, livestock and poultry manure, etc.) are not properly treated, they will cause environmental pollution, such as occupying land resources, polluting soil and water bodies, and releasing greenhouse gases.

[0003] In the treatment and utilization of perishable waste, although aerobic composting of perishable waste has been widely applied, bottleneck problems such as difficult moisture removal, slow start-up temperature rise, long composting cycle, and large floor area caused by high moisture content (≥70%) still restrict the popularization and application of the composting technology. Research shows that although the composting effect and quality can be improved by inoculating compound microbial agents, thermophilic cellulose bacteria, etc., the effect of microbial agents is easily affected by the material composition and native microorganisms and cannot be recycled, and there are huge limitations in terms of stability, effect improvement and cost control.

[0004] In terms of process research, on the basis of the research on traditional composting methods such as windrow composting and in-vessel composting, new processes such as machine composting, ultra-high temperature composting, and hydrothermal pretreatment improve the composting conditions by means of mechanical stirring, aeration and ventilation during the composting process, and have achieved certain results in improving the composting efficiency and product quality. On this basis, more and more research has begun to focus on coupling the biological drying process and the high-temperature composting process to achieve the rapid humification of perishable waste. For example, in the biological drying and composting promotion two-phase integration process and equipment in the invention patents with publication numbers CN115650781A and CN114195562A, the biological drying section is used as the pretreatment process of high-temperature composting, shortening the composting cycle to 7-10 days, and at the same time, the compost product indexes meet the requirements of the "Organic Fertilizer" (NY / T 525—2021) standard. Nevertheless, compared with other resource utilization methods such as anaerobic biogas production, the aerobic composting method does not have an advantage in terms of land utilization rate, which is 2-4 times that of an anaerobic biogas production project with the same treatment scale, seriously hindering the popularization and application of the aerobic composting mode. How to further break through the bottlenecks in the composting cycle and floor area on the basis of the biological drying and composting promotion process is an important research direction for the aerobic composting technology.

[0005] The oxidation of organic matter can release a large amount of heat. According to calculations, the complete oxidation and decomposition of 1g of carbohydrates can produce 16.7kJ of heat, which can raise the temperature of 1kg of perishable garbage by 6~9℃. Perishable garbage contains a large amount of organic matter that is easily oxidized and decomposed, and has great potential for spontaneous heating. In theory, by utilizing the high lattice oxygen activity and redox activity of efficient chemical catalysts, a large amount of active oxygen can be generated at the beginning of composting to promote the catalytic oxidation and heat release of organic matter, which can quickly increase the composting temperature and achieve material dehydration, thereby promoting the rapid succession of functional microorganisms and greatly shortening the composting cycle.

[0006] Therefore, it is urgent to develop efficient catalytic oxidation heat release catalysts for perishable waste, coupled with biological drying and rapid composting technology and equipment, so as to improve the rapid heating, rapid dehydration and rapid humification of organic solid residue composting in the perishable waste treatment industry. However, how to design low-cost and high-efficiency oxidation heat release catalysts and combine them with biological drying and composting technology is a technical problem that needs to be solved urgently. Summary of the invention

[0007] The present invention provides a heat-releasing catalyst and a process for promoting the decomposition of perishable garbage by chemical catalysis and enhanced biological drying to accelerate decomposition, aiming at the bottleneck problems of difficulty in heating and dehydrating in the startup phase, long decomposition cycle, large land occupation, and low fertilizer quality caused by high moisture content of perishable garbage. The present invention accelerates the heating and dehydration of perishable garbage and accelerates the degradation of materials by chemical catalysis and oxidation to shorten the fertilizer-making cycle to 6 to 9 days.

[0008] The specific technical solutions adopted by the present invention are as follows: In a first aspect, the present invention provides a method for preparing a heat-releasing catalyst, comprising mixing a mixed solution of manganese nitrate and a soluble metal salt with carrier particles, performing a reaction under an oscillating state after ultrasonic dispersion to obtain a uniform mixture, wherein the soluble metal salt is a soluble cerium salt or a soluble cobalt salt, and the carrier particles are activated carbon or a molecular sieve; after the reaction is completed, the mixture is allowed to stand for aging, the aged solid is separated, dried, and calcined at 450-550°C for 2.5-3 hours, and cooled to obtain a heat-releasing catalyst.

[0009] As a preferred embodiment of the first aspect, in the mixed solution, the mass ratio of manganese element to metal element in soluble metal salt is (1.5~2.5):1; when the mixed solution is mixed with carrier particles, the mass ratio of manganese element to carrier particles is 1:(20~25).

[0010] As a preferred embodiment of the first aspect, the soluble metal salt is cerium nitrate hexahydrate, and the carrier particles are spherical 13X molecular sieves with a diameter of 3 to 5 mm.

[0011] Preferably, for the first aspect described above, the ultrasonic power for ultrasonic dispersion is at least 200 watts, and the ultrasonic dispersion time is at least 5 minutes; the reaction time of the homogeneous mixture under the oscillating state is at least 2 hours, and the standing aging time after the reaction is at least 12 hours; when drying the separated and aged solid, the drying temperature is 100 - 110 °C, and the drying time is at least 2 hours.

[0012] Preferably, for the first aspect described above, the calcination process is carried out in a muffle furnace, heating up to 450 °C at a rate of 4 °C per minute and then calcining for 3 hours.

[0013] In a second aspect, the present invention provides a heat-releasing catalyst prepared by the preparation method described in any one of the above first aspect solutions.

[0014] In a third aspect, the present invention provides an application of the heat-releasing catalyst described in the second aspect above in accelerating the temperature rise, dehydration, and decomposition of perishable garbage in the aerobic composting process.

[0015] In a fourth aspect, the present invention provides a composting process for chemically catalytically oxidizing heat release to accelerate the temperature rise, dehydration, and decomposition of perishable garbage, which includes: S1. Pretreat the perishable garbage and transfer it as the material to be processed to a sealed biological drying equipment to mix with the old material, and add the heat-releasing catalyst described in the second aspect above accounting for 1% - 5% of the mass of the perishable garbage. After uniformly mixing through full mixing and stirring, carry out intermittent full mixing, aeration, and dehumidification by suction in the biological drying equipment for a residence time of 22 - 24 hours to complete the biological drying stage, and obtain the dried material with a temperature higher than 50 °C and a water content of 55% - 60%. S2. Transfer the dried material to a sealed composting fermentation equipment under heat preservation conditions, adopt a continuous feeding and discharging operation mode and push the material forward by turning and throwing in a plug flow manner to carry out aerobic composting fermentation. During the fermentation process, carry out negative pressure dehumidification by suction throughout the process, and intermittently carry out aeration and turning of the pile, so as to maintain the internal temperature of the material at 55 - 70 °C for more than 5 days; the residence time of the material in the composting fermentation equipment is maintained for 5 - 7 days, and it is output after the internal temperature drops below 40 °C. S3. Use a screening equipment to screen the material output from the composting fermentation equipment, collect the screened heat-releasing catalyst for recycling, and obtain a mature organic fertilizer with a plant seed germination index greater than 70% and a water content lower than 30%.

[0016] Preferably, for the fourth aspect described above, the pretreatment of the perishable waste includes sorting, impurity removal, crushing, and extrusion dehydration. Finally, the water content of the pretreated perishable waste material is maintained at 65-75%, and the particle size is 3-5 cm. The feeding of the biological drying equipment is based on a daily treatment cycle. Before feeding each day, 50%-80% of the dried material in the equipment from the previous day is transferred to the composting and fermentation equipment, and the remaining old material is retained and mixed with the newly pretreated perishable waste of the day.

[0017] Preferably, for the fourth aspect described above, during the aerobic composting and fermentation process, the frequency of intermittent aeration is 5-15 minutes per hour, and the turning frequency is 1 time per day.

[0018] Preferably, for the fourth aspect described above, when recycling the heat-releasing catalyst, the heat-releasing catalyst screened out by the screening equipment needs to be cleaned, dried, and then re-added to the biological drying equipment for reuse.

[0019] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention gives full play to the role of organic matter heat-releasing catalysis in the fully mixed biological drying system. The heat generated by chemical catalysis can reach 50%-80% of the heat generated by biochemical decomposition, rapidly increasing the temperature of the compost pile in the early stage of composting, promoting the removal of moisture from the material, and significantly shortening the microbial growth lag period caused by the entry of new materials. The start-up heating time is shortened during the process, the original microbial quantity of perishable waste is rapidly amplified, the succession of thermophilic functional microorganisms is strengthened, and the efficient degradation effect of dominant microorganisms is exerted. Without adding microbial agents, the composting cycle is shortened to 6-9 days, greatly saving the land occupation cost.

[0020] (2) Compared with the composting process with microbial agent addition and external auxiliary heating, the catalyst used in the present invention can be recycled, greatly saving the operation cost.

[0021] (3) The composting process of the present invention for accelerating the heating, dehydration, and composting of perishable waste by chemical catalytic oxidation heat release, through the addition of a recyclable heat-releasing catalyst, synergistically acts with microorganisms to strengthen the decomposition, further realizing the rapid dehydration and composting of perishable waste. The perishable waste can be converted into a mature fertilizer meeting the standard of "Organic Fertilizer" (NY / T 525-2021) within 6-9 days, overcoming the bottleneck problems of traditional composting such as difficult heating and dehydration in the start-up stage, long composting cycle, large land occupation area, and low fertilizer quality, and realizing the efficient resource utilization of perishable waste. Description of the Drawings

[0022] Figure 1 It is a flow chart for the preparation of the heat-releasing catalyst.

[0023] Figure 2 It is a flow chart for the composting process of accelerating the heating, dehydration, and composting of perishable waste by chemical catalytic oxidation heat release. Detailed implementation manners

[0024] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description through specific implementation manners. Many specific details are set forth in the following description to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below. The technical features in various embodiments of the present invention can be combined correspondingly without conflict.

[0025] The present invention provides a heat-releasing catalyst and a preparation method thereof, and at the same time provides a composting process for accelerating the temperature rise, dehydration, and decomposition of perishable garbage by chemical catalytic oxidation based on the heat-releasing catalyst. The basic concept of the present invention is to give full play to the oxidation of organic matter by chemical catalysts in a fully mixed biodrying system, release a large amount of heat energy, rapidly increase the temperature of the compost pile in the early stage of composting, promote the removal of material moisture, greatly shorten the microbial growth lag period caused by the entry of new materials, and accelerate the succession of functional microorganisms. The present invention breaks the traditional idea of relying solely on biological heat generated by microorganisms in composting, combines chemical catalysis with microbial decomposition, effectively overcomes the bottleneck problems of difficult temperature rise and dehydration, long decomposition period, large floor area, and low fertilizer quality in the starting stage, shortens the composting period to 6 - 9 days, and obtains a decomposed fertilizer with a seed germination index as high as 90%, providing a reference for the efficient and rapid fertilization of perishable garbage.

[0026] The following provides a detailed description of the heat-releasing catalyst and its preparation method of the present invention.

[0027] In a preferred embodiment of the present invention, a preparation method of a heat-releasing catalyst is provided. As Figure 1 shown, the present invention uses ultrasonic dispersion - two-step hydrothermal method to prepare a manganese-cerium bimetal-supported heat-releasing catalyst. The specific method is as follows: Mix a mixed solution of manganese nitrate and a soluble metal salt with carrier particles, obtain a uniform mixture by ultrasonic dispersion, and then react under a shaking state. The soluble metal salt is a soluble cerium salt or a soluble cobalt salt, and the carrier particles are activated carbon or molecular sieve; after the reaction is completed, let it stand for aging, separate the aged solid, dry it, and then calcine it at 450 - 550 °C for 2.5 - 3 hours, and cool it to obtain the heat-releasing catalyst.

[0028] In the above preparation method, the manganese element (Mn) in manganese nitrate and the metal elements (Ce, Co) in soluble metal salts are the elements that control the active sites in the catalyst. The ratio between these elements needs to be reasonably optimized to ensure that a good heat release catalytic effect can be finally obtained. In a preferred embodiment of the present invention, in the above mixed solution, the mass ratio of the manganese element to the metal elements in the soluble metal salt (i.e., Mn:Ce or Mn:Co) is (1.5 - 2.5):1.

[0029] In addition, the ratio between the elements that control the active sites in the catalyst and the carrier should also be reasonably optimized. In a preferred embodiment of the present invention, when the above mixed solution is mixed with the carrier particles, the mass ratio of the manganese element to the carrier particles is 1:(20 - 25).

[0030] In addition, the specific reagents and materials of each raw material in the above preparation method can be optimized according to the final performance. In a preferred embodiment of the present invention, the above soluble metal salts can all be nitrates, that is, the soluble cerium salt is cerium nitrate, and the soluble cobalt salt is cobalt nitrate. And the above carrier particles can be activated carbon or molecular sieve, and the molecular sieve can be 5A molecular sieve or 13X molecular sieve. The selection of the molecular sieve diameter can be adjusted according to the pretreatment crushing process and equipment conditions of perishable garbage according to actual needs to achieve the recovery of the catalyst. The purity of the selected various reagents is recommended to be analytical pure or higher purity.

[0031] In a preferred embodiment of the present invention, among the three raw materials of the above preparation method, in addition to manganese nitrate, the other two materials can be preferably as follows: the soluble metal salt is cerium nitrate hexahydrate, and the carrier particles are spherical 13X molecular sieves with a diameter of 3 - 5 mm; and the mass ratio of the manganese element to the cerium element is 2:1, the mass ratio of the manganese element to the carrier particles is 1:20, and the mass ratio of the cerium element to the carrier particles is 1:40. Thus, based on the carrier particles, that is, spherical 13X molecular sieves, the mass percentages of the manganese element and the cerium element in the carrier particles are 5% and 2.5% respectively. In this optimal combination, using 13X molecular sieve as the carrier can facilitate the subsequent separation and recovery of the catalyst, and the loading method of 5% Mn + 2.5% Ce shows higher heating promotion activity compared with other catalyst raw material combinations, which is more conducive to the rapid start of the biological drying and composting promotion process.

[0032] In addition, in the above preparation method of the heat-releasing catalyst, the corresponding process parameters also need to be reasonably optimized. Among them, the ultrasonic power of the above ultrasonic dispersion is at least 200 watts, and the ultrasonic dispersion time is at least 5 minutes. Through ultrasonic dispersion, manganese and cerium can be evenly dispersed and the bubbles in the molecular sieve pores can be discharged, improving the loading efficiency. The reaction time of the above uniform mixture under the shaking state is at least 2 hours, and the standing aging time after the reaction is at least 12 hours; when drying the separated and aged solid, the drying temperature is 100-110 °C, and the drying time is at least 2 hours.

[0033] In addition, for the dried solid, its calcination temperature needs to be raised to 450-550 °C at a certain heating rate, calcined for 2.5-3 hours, and then naturally cooled. Controlling a certain heating and cooling rate in the present invention is beneficial to preventing furnace temperature overshoot and excessive temperature difference between the inside and outside of the catalyst, ensuring the stability of the catalyst structure. It should be noted that it is best to cool naturally slowly during the cooling process, because the rapid cooling-induced temperature drop is likely to cause the catalyst to burst.

[0034] The heat-releasing catalyst prepared by the above preparation method can be used as a catalyst for mixing with perishable garbage materials in the aerobic composting process, to accelerate the temperature rise, dehydration and decomposition of perishable garbage, shorten the decomposition cycle of the materials, and improve the degree of decomposition of the materials. Specifically, adding the above heat-releasing catalyst to the biological drying process of perishable garbage can improve the material pores and promote the conversion of oxygen into active oxygen, catalytically oxidize organic matter to generate a large amount of heat energy, promote the temperature rise of the biological drying and humification process and the decomposition of organic matter, and promote the efficient succession of thermophilic functional microorganisms, thereby shortening the composting cycle to 6-9 days and obtaining a mature fertilizer with a seed germination index as high as 90%. The specific application of this heat-releasing catalyst will be described in detail below.

[0035] In the embodiments of the present invention, a composting process for accelerating the temperature rise, dehydration and decomposition of perishable garbage by chemical catalytic oxidation heat release is provided, which includes the following steps S1-S3, Figure 2 The overall flow chart of this composting process is shown. The specific implementation methods of each step will be described in detail below.

[0036] S1. After pretreating the perishable garbage, transfer it as the material to be processed to a sealed biological drying device, mix it with the old material, and add 1%-5% of the above heat-releasing catalyst based on the mass of the perishable garbage. After uniformly mixing by full mixing, carry out intermittent full mixing, aeration and ventilation and dehumidification on the mixed material in the biological drying device for a residence time of 22-24 hours to complete the biological drying stage, and obtain dried material with a temperature higher than 50 °C and a moisture content of 55%-60%.

[0037] It should be noted that in the present invention, the perishable waste is preferably the kitchen waste generated from the classification of general household waste. Before the perishable waste is transferred to the biological drying equipment, necessary pretreatment is required to meet the requirements of composting. The specific pretreatment measures to be taken need to be determined according to the nature of the waste, including but not limited to sorting, impurity removal, crushing and extrusion dehydration. Non-organic matters such as stones, plastics, and metals are removed through sorting and impurity removal, and the impurities need to be transported out for treatment. In the present invention, the particle size and moisture content of large pieces of materials are controlled through crushing and dehydration, making it more suitable for humification composting. Additionally, when necessary, auxiliary materials such as wood chips, straws, and withered leaves or other microbial agent products can be added according to the situation to achieve faster decomposition. Finally, the moisture content of the pretreated perishable waste material transferred to the biological drying equipment should be maintained at 65-75%, and the particle size should be controlled at 3-5 cm preferably.

[0038] The dosage of the heat-releasing catalyst added in the present invention is determined according to the actual operation effect, and the dosage can be appropriately increased for materials with high moisture content and low porosity.

[0039] In addition, during the biological drying process, the above-mentioned full mixing and stirring need to fully mix and stir all the materials to ensure the uniform mixing of the waste materials and the heat-releasing catalyst. The stirring duration is generally controlled at 10-20 minutes preferably.

[0040] During the entire biological drying process, full mixing and stirring, aeration, and ventilation and dehumidification should be carried out intermittently at preset intervals. The intermittent operation cycle of full mixing and stirring, aeration, and ventilation and dehumidification can be adjusted according to actual needs. Generally, one hour can be used as an intermittent cycle, that is, full mixing and stirring, aeration, and ventilation and dehumidification are performed once every hour to ensure that the materials are in a fully aerobic state. However, at the initial stage of the start of biological drying, due to the low activity of microorganisms and slow oxygen consumption, the intermittent cycle can be appropriately extended.

[0041] In order to ensure that the above-mentioned biological drying equipment can maintain a relatively stable biological drying effect, the feeding of the biological drying equipment can be based on a daily treatment cycle. Before feeding every day, 50%-80% of the dried materials after biological drying in the equipment on the previous day are transferred to the composting and fermentation equipment, and the remaining old materials (i.e., the remaining 50%-20% of the dried materials) are retained and mixed with the newly pretreated perishable waste on the same day. Thus, through the mixing mode of old materials and new materials, the stability of the microbial population in the materials can be fully ensured, and the overly long start-up time can be avoided.

[0042] In the present invention, a heat-releasing catalyst is added during the biological drying process, which can promote the oxidative decomposition of organic matter in the materials, thereby releasing a large amount of heat and promoting water removal, providing a suitable environment for the rapid reproduction of microorganisms, with an amplification factor as high as 100-300 times, greatly shortening the humification cycle of perishable waste. When the biological drying link is quickly completed, the subsequent aerobic composting and fermentation link can be carried out.

[0043] S2. Transfer the dried material to a sealed composting and fermenting device under heat preservation conditions. Adopt a continuous feeding and discharging operation mode and a pushing-type turning and throwing propulsion mode to carry out aerobic composting and fermentation. During the fermentation process, negative pressure air extraction and dehumidification are carried out throughout the process, and aeration and turning are carried out intermittently, so that the internal temperature of the material is maintained at 55-70 °C for more than 5 days; the residence time of the material in the composting and fermenting device is kept at 5-7 days, and it is output after the internal temperature drops below 40 °C.

[0044] It should be noted that since the dried material was originally in the biological drying device and needs to be transferred to the composting and fermenting device for aerobic composting and fermentation, heat preservation measures need to be taken during this transfer process to avoid losing the heat generated during the biological drying process.

[0045] The continuous feeding and discharging method adopted in the above composting and fermenting device, that is, the dried material after drying is continuously input at the feeding port, and then the dried material input from the feeding port is continuously turned and thrown forward through the operation mode of the pushing-type turning machine. The pushing-type turning machine can be realized by a chain plate turning machine. The chain plate turning machine can be installed on the plane walking drive mechanism and is driven by the plane walking drive mechanism to move from the feeding port to the discharging port inside the composting and fermenting device. And the chain plate turning machine obliquely extends into the material in the device and turns and throws the material at the position to the side close to the discharging end. Thus, different batches of materials will not be mixed with each other during the turning process, so that the materials are pushed towards the outlet end while turning the materials, which belongs to a progressive composting process.

[0046] In addition, during the above aerobic composting and fermentation process, negative pressure air extraction and dehumidification need to be carried out throughout the device, but the aeration and turning operations need to be carried out intermittently. The frequency of intermittent aeration is preferably controlled at 5-15 minutes / hour, that is, aeration is carried out for 5-15 minutes per hour, and no aeration is carried out for the rest of the time; while the turning frequency is preferably controlled at 1 time / day. The turning frequency and the distance of a single turning need to be determined according to the fermentation tank size and residence time of the composting and fermenting device, and it should be ensured that the material has sufficient residence time in the composting and fermenting device. In the embodiments of the present invention, the residence time of the material in the composting and fermenting device should be controlled at 5-7 days. The corresponding composting tank in the composting and fermenting device should be designed to have a sufficient length to ensure sufficient residence time.

[0047] Since the dried material of the present invention contains heat-releasing catalysts and a large amount of highly active thermophilic microorganisms are enriched in the material, under the control conditions of the above S2 step, after the material enters the sealed composting fermentation equipment for aerobic composting fermentation, the internal temperature of the material pile can rapidly rise above 60°C (it can reach 60-75°C) in the initial stage of fermentation (generally within 24 hours after the new material enters the composting fermentation equipment). The aeration frequency in the composting bin needs to be dynamically adjusted according to the pile temperature. When the temperature is high, more aeration is required to ensure sufficient oxygen supply and prevent high temperature from killing microorganisms. It should be noted that after the turning device turns the material backward, each batch of materials entering the composting bin is basically located on the same cross-sectional layer in the axial direction of the inner bin (the connection line between the inlet end and the outlet end), so as to ensure that each batch of materials has the same and sufficient residence time. In the present invention, by adjusting the aeration and turning operations, the internal temperature of the material can be controlled at 55-70°C for more than 5 days to make the material quickly and fully compost. The material to be treated needs to maintain a residence time of 5-7 days in the composting fermentation equipment, and after the internal temperature drops below 40°C, it can be output from the equipment and enter the drum screen at the end of the equipment. Of course, in special cases where the ambient temperature is low and the pile temperature rises abnormally, the residence time can be appropriately extended according to the actual situation of the material.

[0048] It should be noted that the above biological drying equipment can be any sealed biological drying equipment with the functions of aeration, stirring, and heat preservation, and the above composting fermentation equipment can be a sealed composting fermentation equipment with the functions of aeration, turning, and heat preservation. The biological drying equipment and the composting fermentation equipment can be a separate drying bin and composting bin. In this case, heat preservation measures need to be taken during the material transportation and transfer process between the two, and at the same time, the outside of the drying bin and the composting bin should also be covered with heat preservation materials. An aeration device, a stirring device, and an exhaust device for ventilation and dehumidification need to be set inside the drying bin, while an aeration device, a stirring device, and an exhaust device for ventilation and dehumidification also need to be set inside the composting bin. However, the stirring device in the drying bin needs to fully mix the material, and a turning machine or a screw stirring mechanism capable of fully mixing the material can be used. The stirring device in the composting bin does not need to fully mix the material, and the aforementioned push-flow turning machine can be used. In addition, the drying bin and the composting bin can also be integrated. For example, the perishable waste treatment device described in the invention patent with the application number CN202211138803.4 and the invention name "Perishable Waste Treatment Device and Process for Biological Drying and Promoting Composting" can be used to achieve this.

[0049] In addition, it should be noted that in the above S1 and S2 steps, the material generates heat by itself and does not require the introduction of an external heat source.

[0050] S3. Use a screening device to screen the materials output by the composting and fermentation device, collect the screened heat-releasing catalyst for recycling, and obtain a mature organic fertilizer with a plant seed germination index greater than 70% and a moisture content lower than 30%.

[0051] It should be noted that the main function of the above screening device is to separate the heap materials and the heat-releasing catalyst. Equipment suitable for separating these two types of materials can be used, such as a drum screen. The specific screening particle size can be selected according to the particle size of the heat-releasing catalyst. In the embodiments of the present invention, since the prepared heat-releasing catalyst is spherical particles with a diameter of 3 - 5 mm, a drum screen with a screen aperture of 3 - 5 mm can also be selected. After screening the materials with a drum screen, the heat-releasing catalyst screened out below the screen can be collected, cleaned, dried, and sent back to the biological drying equipment for reuse. However, it should be noted that the heat-releasing catalyst obtained by screening in the present invention will be mixed with relatively small particles of mature materials. Generally speaking, the catalyst mixed with mature materials can be directly transported back to the biological drying bin for addition and use. However, due to the long-term use of the catalyst, the surface pores may be blocked, affecting the catalytic effect. In actual operation, the heat-releasing catalyst can be secondarily screened as needed, soaked, cleaned, dried, regenerated, and reused. The impurities generated by screening can be transported out for treatment.

[0052] The following shows the preparation method of the above heat-releasing catalyst and the technical effects of the application of such heat-releasing catalyst in the aerobic composting process through several embodiments.

[0053] Example 1. Preparation of the heat-releasing catalyst In this example, a heat-releasing catalyst for accelerating the composting of perishable garbage was prepared. The specific preparation method is as follows: 1). Prepare a mixed solution of manganese nitrate and cerium nitrate: Mix 46.48 g of cerium nitrate hexahydrate (Ce(NO 3 ) 3 ·6H 2 O) with 195.44 g of a 50% manganese nitrate solution by mass, and then make up the volume to 1 L with pure water to obtain a mixed solution of manganese nitrate and cerium nitrate (which contains approximately 30 g of manganese element and approximately 15 g of cerium element); then, according to the solid-liquid ratio of molecular sieve mass (kg): mixed solution volume (L) = 3:5, fully mix the mixed solution with spherical artificial 13X molecular sieve with a diameter of 3 - 5 mm to obtain a mixture. In this mixture, calculated based on the 13X molecular sieve, the mass percentages of manganese element and cerium element relative to the 13X molecular sieve are 5% and 2.5% respectively.

[0054] 2). After ultrasonic dispersing the mixture obtained in step 1) with a power of 200 watts for 5 minutes, place it in a shaker and shake at 180 revolutions per minute for 2 hours, then let it stand for aging for 12 hours, and finally perform solid-liquid separation to obtain the aged solid.

[0055] 3), After spreading the aged solid obtained in step 2) flat in an oven at 105 °C for 2 hours, transfer it to a muffle furnace, heat it up to 450 °C at a rate of 4 °C per minute, calcine for 3 hours, and take it out after natural cooling to obtain an exothermic catalyst. In the exothermic catalyst prepared in this example, the carrier is 13X molecular sieve, and the loading sites are 5% Mn + 2.5% Ce.

[0056] Example 2. Preparation of exothermic catalyst In this example, an exothermic catalyst for accelerating the composting of perishable garbage was prepared. The specific preparation method is as follows: 1), Prepare a mixed solution of manganese nitrate and cobalt nitrate: Mix 74.07 g of cobalt nitrate hexahydrate (Co(NO 3 ) 2 ·6H 2 O) with 195.44 g of a 50% manganese nitrate solution by mass, and make up the volume to 1 L with pure water to obtain a mixed solution of manganese nitrate and cobalt nitrate (containing approximately 30 g of manganese element and 15 g of cobalt element); then, according to the solid-liquid ratio of molecular sieve mass (kg): mixed solution volume (L) = 3:5, fully mix the mixed solution with spherical artificial 13X molecular sieve with a diameter of 3 - 5 mm to obtain a mixture. In this mixture, based on the conversion of 13X molecular sieve, the mass percentages of manganese element and cobalt element relative to 13X molecular sieve are 5% and 2.5% respectively.

[0057] 2), After subjecting the mixture obtained in step 1) to ultrasonic dispersion with a power of 200 watts for 5 minutes, place it in a shaker and shake it at 180 revolutions per minute for 2 hours, then let it stand for aging for 12 hours, and finally separate the solid and liquid to obtain the aged solid.

[0058] 3), After spreading the aged solid obtained in step 2) flat in an oven at 105 °C for 2 hours, transfer it to a muffle furnace, heat it up to 450 °C at a rate of 4 °C per minute, calcine for 3 hours, and take it out after natural cooling to obtain an exothermic catalyst. In the exothermic catalyst prepared in this example, the carrier is 13X molecular sieve, and the loading sites are 5% Mn + 2.5% Co.

[0059] Comparative Example 1. Preparation of exothermic catalyst In this comparative example, an exothermic catalyst for composting perishable garbage was prepared. The specific preparation method is as follows: 1), Preparation of manganese nitrate solution: 195.44 g of manganese nitrate solution with a mass percentage of 50% was diluted to 1 L with pure water to obtain a manganese nitrate solution (containing approximately 30 g of manganese element); then, according to the solid-liquid ratio of molecular sieve mass (kg): manganese nitrate solution volume (L) = 3:5, the mixed solution was fully mixed with spherical artificial 13X molecular sieve with a diameter of 3 - 5 mm to obtain a mixture. In this mixture, calculated based on the 13X molecular sieve, the mass percentage of manganese element and cobalt element relative to the 13X molecular sieve was 5%.

[0060] 2), The mixture obtained in step 1) was ultrasonically dispersed at a power of 200 watts for 5 minutes, then placed in a shaker and shaken at 180 revolutions per minute for 2 hours, and then left to age for 12 hours. Finally, solid-liquid separation was carried out to obtain the aged solid.

[0061] 3), The aged solid obtained in step 2) was spread out flat in an oven at 105°C and dried for 2 hours, then transferred to a muffle furnace and heated to 450°C at a rate of 4°C per minute, calcined for 3 hours, and taken out after natural cooling to obtain the heat-releasing catalyst. In the heat-releasing catalyst prepared in this example, the carrier was 13X molecular sieve and the loading site was 5% Mn.

[0062] Example 3, Preparation of heat-releasing catalyst In this example, a heat-releasing catalyst for accelerating the composting of perishable waste through biodrying was prepared. The difference from Example 1 was only that the carrier was replaced from 13X molecular sieve to 5A molecular sieve, and the other procedures were the same. Thus, in the heat-releasing catalyst prepared in this example, the carrier was 5A molecular sieve and the loading site was 5% Mn + 2.5% Ce.

[0063] Example 4, Preparation of heat-releasing catalyst In this example, a heat-releasing catalyst for accelerating the composting of perishable waste through biodrying was prepared. The difference from Example 2 was only that the carrier was replaced from 13X molecular sieve to 5A molecular sieve, and the other procedures were the same. Thus, in the heat-releasing catalyst prepared in this example, the carrier was 5A molecular sieve and the loading site was 5% Mn + 2.5% Co.

[0064] Comparative Example 2, Preparation of heat-releasing catalyst In this comparative example, a heat-releasing catalyst for accelerating the composting of perishable waste through biodrying was prepared. The difference from Comparative Example 1 was only that the carrier was replaced from 13X molecular sieve to 5A molecular sieve, and the other procedures were the same. Thus, in the heat-releasing catalyst prepared in this comparative example, the carrier was 5A molecular sieve and the loading site was 5% Mn.

[0065] Example 5, Preparation of heat-releasing catalyst In this example, a heat-releasing catalyst for accelerating the decomposition of perishable garbage by biological drying is prepared. The difference between this example and Example 1 is that the carrier is replaced by activated carbon instead of 13X molecular sieve, and the rest of the methods are the same. In the heat-releasing catalyst prepared in this example, the carrier is activated carbon, and the loading site is 5% Mn + 2.5% Ce.

[0066] Example 6. Preparation of heat-releasing catalyst In this example, a heat-releasing catalyst for accelerating the decomposition of perishable garbage by biological drying is prepared. The difference between this example and Example 2 is that the carrier is replaced by activated carbon instead of 13X molecular sieve, and the rest of the methods are the same. In the heat-releasing catalyst prepared in this example, the carrier is activated carbon, and the loading site is 5% Mn + 2.5% Co.

[0067] Comparative Example 3: Preparation of heat-releasing catalyst In this comparative example, a heat-releasing catalyst for accelerating the decomposition of perishable garbage by biological drying is prepared. The difference between this example and comparative example 1 is that the carrier is replaced by activated carbon from 13X molecular sieve, and the rest of the methods are the same. In the heat-releasing catalyst prepared in this comparative example, the carrier is activated carbon, and the loading site is 5% Mn.

[0068] Example 7: Verification of the heating effect of different heat-releasing catalysts In this embodiment, based on the heat-releasing catalysts prepared under 9 different carriers and active site ratios in the above-mentioned Examples 1 to 6 and Comparative Examples 1 to 3, they were applied to the biological drying aerobic fermentation process to verify their effect of promoting the temperature rise of the material. The specific experimental process of this embodiment is as follows: The perishable garbage collected and classified from the nearby garbage transfer station was collected for pretreatment. The moisture content was maintained at 65-75% and the particle size was 3-5 cm by sorting, removing impurities, crushing and extruding dehydration. After the material was fully mixed, the bio-drying reactor was started and operated. Ten groups of control experiments were set up using this batch of materials, of which 9 experimental groups were added with 9 different heat-releasing catalysts (the addition amount was 3 wt.% of the mass of the perishable garbage material after pretreatment), and the control group did not add any catalyst. Three parallels were set up for each group. Before the experiment started, the full mixing of the bio-drying bin was started for 20 minutes to ensure that the experimental materials were fully uniform. After the materials and catalysts were fully mixed according to the groups and the starting temperature was controlled to be similar, they were placed in a customized high-insulation composting tank for fermentation test. The aeration frequency was controlled to 1 minute / hour, and the pile was not turned over during the period and there was no external heating. The temperature changes of each group were measured after 8 hours of reaction. The experimental results are shown in Table 1.

[0069] Table 1

[0070] As can be seen from Table 1, among the 9 groups of different catalysts, the heat-releasing catalysts prepared in Examples 1 to 6 of the present invention all achieved better temperature-raising effects than the catalysts in Comparative Examples 1 to 3. In particular, with 13X molecular sieve as the carrier, the loading method of 5% Mn + 2.5% Ce showed the highest temperature-raising activity, which was more conducive to the rapid initiation of the biological drying and composting process.

[0071] Example 8. Verification of the temperature-raising and dehydration effect of the heat-releasing catalyst In this example, the heat-releasing catalyst prepared in Example 1 (with 13X molecular sieve as the carrier and 5% Mn + 2.5% Ce as the loading site) was further used for experiments to verify the temperature-raising and dehydration effect of the heat-releasing catalyst for the biological drying and accelerated composting of perishable garbage on the materials during the composting startup temperature-raising stage, so as to prove the feasibility of the present invention. The specific experimental process of this example is as follows: Collect perishable garbage collected by a nearby garbage transfer station for pretreatment. Through sorting, impurity removal, crushing and extrusion dehydration, the moisture content is kept at 65 - 75%, and the particle size is 3 - 5 cm. After fully mixing the materials, start and run the biological drying reactor. Using this batch of materials, 3 groups of control experiments were set up, namely 5% heat-releasing catalyst addition, 5% blank molecular sieve addition and blank without addition, and three parallels were set in each group. Before the experiment started, the full-mix stirring of the biological drying bin was started for 20 minutes to ensure the full uniformity of the experimental materials. After fully mixing the materials and the heat-releasing catalyst according to the groups and controlling the initial temperatures to be similar, they were placed in a customized high-insulation composting tank for fermentation experiments. The aeration frequency was controlled at 1 minute / hour, and there was no turning of the pile and no external heating during the period. The temperature and moisture content changes of each group were measured. After 8 hours of fermentation, the temperatures of the catalytic group, the molecular sieve group and the blank group rose from 40.2 ± 0.4 °C to 55.6 ± 1.4 °C, 46.9 ± 0.6 °C, and 44.5 ± 0.1 °C respectively. The temperature-raising effect was 258% higher than that of the blank, and the temperature-raising effect of the catalyst was significant. After 8 hours of fermentation, the water removal amounts of the catalytic group, the molecular sieve group and the blank group were 30.9 ± 3.3 g / kg, 5.3 ± 1.2 g / kg, and 8.5 ± 0.5 g / kg respectively. The dehydration effect of the catalyst was significant. Therefore, the results show that the application of the heat-releasing catalyst prepared in the present invention has a significant effect on the temperature-raising and dehydration of the materials, which is conducive to the rapid initiation of the biological drying and composting process.

[0072] Example 9. Experiment on the optimal dosage of the heat-releasing catalyst In this example, the heat-releasing catalyst prepared in Example 1 (with 13X molecular sieve as the carrier and 5% Mn + 2.5% Ce as the loading site) was further used for experiments to verify the temperature-raising and dehydration effect of different dosages of the heat-releasing catalyst on the materials, so as to determine the appropriate dosage for actual use. The specific experimental process of this example is as follows: Collect the perishable waste sorted and collected by nearby garbage transfer stations for pretreatment. Through sorting, impurity removal, crushing, and extrusion dehydration, keep its moisture content at 65 - 75% and the particle size at 3 - 5 cm. After fully mixing this material, start and operate the biological drying reactor. Set up 4 groups of control experiments with this batch of materials, namely 5% heat-releasing catalyst addition, 3% heat-releasing catalyst addition, 1% heat-releasing catalyst addition, and 0% heat-releasing catalyst addition, with three parallels set for each group. Before the experiment starts, start the full-mix stirring of the biological drying bin for 20 minutes to ensure the full uniformity of the materials used in the experiment. After fully mixing the materials and the heat-releasing catalyst according to the groups and controlling the initial temperatures to be similar, place them in a customized high-insulation composting tank for fermentation experiments. Control the aeration frequency at 1 minute / hour, without turning the pile and without external heating during the period, and measure the temperature and moisture content changes of each group. After 8 hours of fermentation, the temperatures of the 5%, 3%, 1%, and 0% heat-releasing catalyst addition groups rise from 38.0 ± 0.5 °C to 52.6 ± 1.1 °C, 52.2 ± 0.3 °C, 50.8 ± 0.7 °C, and 44.4 ± 0.1 °C respectively. The temperature-raising effect is increased by 258% compared to the blank, and the temperature-raising effect of the catalyst is significant. After 8 hours of fermentation, the water removal amounts of the 5%, 3%, 1%, and 0% heat-releasing catalyst addition groups are 31.8 ± 2.9 g / kg, 31.5 ± 0.5 g / kg, 18.7 ± 3.5 g / kg, and 10.8 ± 1.4 g / kg respectively. The water-dehydrating effect of the catalyst is significant. Therefore, the results show that the heat-releasing catalyst prepared by the present invention has a significant effect on promoting the temperature rise and water dehydration of the materials at an addition amount of 1 - %% (the specific percentage is not clear in the original text). It should be noted that under the experimental conditions, the temperature-raising and water-dehydrating effects are close at the addition amounts of 5% and 3%, but are significantly higher than the 1% addition amount and the blank.

[0073] Example 10: Verification of the effect of the heat-releasing catalyst on improving the degree of maturity In this example, further based on the heat-releasing catalyst prepared in Example 1 (the carrier is 13X molecular sieve, and the loading site is 5% Mn + 2.5% Ce), through biological drying experiments under the operating conditions of adding the heat-releasing catalyst in the whole process, verify the effect of the heat-releasing catalyst on shortening the composting cycle and improving the degree of maturity of the materials. The specific experimental process of this example is as follows: The perishable garbage collected and classified from the nearby garbage transfer station was collected for pretreatment. The moisture content was maintained at 65-75% and the particle size was 3-5 cm through sorting, impurity removal, crushing and extrusion dehydration. After the material was fully mixed, the biological drying reactor was started and operated. Three groups of control experiments were set up using this batch of materials, including 5% heat release catalyst addition, 5% blank molecular sieve addition and blank without addition, with three parallels in each group. After the biological drying equipment completed the loading of the material to be processed, it started the built-in mixer, the external equipment connected to the aeration pipeline and the exhaust dehumidification equipment, and operated according to the set intermittent operation mode. The specific operating conditions of the intermittent operation mode are: with an intermittent cycle of 1 hour, aeration and exhaust dehumidification are operated in linkage for 15 minutes, and aeration and exhaust dehumidification are carried out while the linkage is running. At the same time, full mixing and stirring are carried out for 10 minutes after the aeration is started. No full mixing, aeration and exhaust dehumidification are carried out for the remaining 45 minutes in an intermittent cycle. The materials to be treated that have completed biological drying in the biological drying equipment are directly transferred from the discharge port to the closed and insulated composting and fermentation equipment for aerobic composting and fermentation. The composting and fermentation equipment operates in a continuous feeding and discharging mode. The newly transferred materials to be treated are piled at the inlet end of the composting and fermentation equipment, and will not be completely mixed with the existing materials in the composting and fermentation equipment, but will be layered. During the aerobic composting and fermentation process, the compost turning device, mixer, external equipment connected to the aeration pipeline and exhaust and dehumidification equipment in the composting and fermentation equipment operate according to the preset layered operation mode. The specific operating conditions are: exhaust and dehumidification are carried out throughout the fermentation process, and all materials to be treated are intermittently turned and aerated. The aeration frequency is 20 minutes / hour, and the turning frequency is 1 time / day.

[0074] Finally, after 7, 9, and 11 days of maturity cycles, the materials in the catalytic group, carrier group, and blank group were cooled and matured successively. The seed germination index of the obtained mature fertilizer was determined, and it was found that the seed germination index of the catalytic group, carrier group, and blank group was 92.8±3.9%, 79.0±5.3%, and 81.0±1.6%, respectively, and the maturity of the catalytic group was significantly increased. Other indicators of the obtained mature fertilizer were determined, with a moisture content of 19.9% ​​to 26.2% and a pH of 8.21 to 8.37. The relevant indicators all met the requirements of the "Organic Fertilizer" (NY / T 525-2021) standard. In addition, after 7, 9, and 11 days of maturity cycles, the humic acid (HA) content of the catalytic group, carrier group, and blank group materials was 46.8±1.2, 40.8±1.5, and 35.8±1.6 g / kg, respectively, and the humic acid content of the catalytic group materials increased by 30.7%.

[0075] In summary, the present invention provides a heat-releasing catalyst for accelerating the composting of perishable waste through biodrying. This heat-releasing catalyst can further promote the temperature rise and dehydration in the biodrying and composting process, achieving the rapid conversion of perishable waste into organic fertilizer. The present invention breaks the traditional idea of relying solely on the biological heat generated by microorganisms in composting, combines chemical catalysis with microbial decomposition, and effectively solves the problems such as poor temperature rise and dehydration effect, long composting cycle, and low degree of maturity during the fertilizer conversion process of perishable waste, providing a reference for the efficient, low-consumption and rapid treatment of perishable waste in engineering practice.

[0076] The above-described embodiments are only some preferred implementation solutions of the present invention, but are not intended to limit the present invention. Those of ordinary skill in the relevant technical fields can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all technical solutions obtained by means of equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A method for preparing a heat-releasing catalyst, characterized in that: A mixed solution of manganese nitrate and a soluble metal salt is mixed with carrier particles, and a uniform mixture is obtained by ultrasonic dispersion, followed by reaction under shaking, wherein the soluble metal salt is a soluble cerium salt or a soluble cobalt salt, and the carrier particles are activated carbon or a molecular sieve; after the reaction is completed, the mixture is allowed to stand for aging, the aged solid is separated, dried, and then calcined at 450-550° C. for 2.5-3 hours, and cooled to obtain a heat-releasing catalyst.

2. The method for preparing a heat-releasing catalyst according to claim 1, characterized in that: In the mixed solution, the mass ratio of manganese element to metal element in soluble metal salt is (1.5-2.5):1; when the mixed solution is mixed with carrier particles, the mass ratio of manganese element to carrier particles is 1:(20-25).

3. The method for preparing a heat-releasing catalyst according to claim 1, characterized in that: The soluble metal salt is cerium nitrate hexahydrate, and the carrier particles are spherical 13X molecular sieves with a diameter of 3 to 5 mm.

4. The method for preparing a heat-releasing catalyst according to claim 1, characterized in that: The ultrasonic power of the ultrasonic dispersion is at least 200 watts, and the ultrasonic dispersion time is at least 5 minutes; the uniform mixture is reacted in an oscillating state for at least 2 hours, and is allowed to stand for aging after the reaction is completed for at least 12 hours; when the separated and aged solid is dried, the drying temperature is 100-110° C., and the drying time is at least 2 hours.

5. A heat-releasing catalyst prepared by the preparation method according to any one of claims 1 to 4.

6. Use of the heat-releasing catalyst as claimed in claim 5 to accelerate the heating, dehydration and maturity of perishable garbage in an aerobic composting process.

7. A composting process for accelerating the heating, dehydration and maturity of perishable garbage by chemical catalytic oxidation and heat release, characterized in that: include: S1. Transfer the pre-treated perishable garbage as the material to be processed to a sealed biological drying device and mix it with the old material, and add the heat-releasing catalyst as claimed in claim 5, which accounts for 1% to 5% of the mass of the perishable garbage. After fully mixing and stirring, the mixed material is subjected to intermittent full mixing, aeration and dehumidification by ventilation in the biological drying device for a residence time of 22 to 24 hours to complete the biological drying stage, and obtain a dried material with a temperature higher than 50° C. and a moisture content of 55% to 60%; S2. Transfer the dried material to a sealed composting and fermentation equipment under heat preservation conditions, and carry out aerobic composting and fermentation by adopting a continuous feeding and discharging operation mode and pushing through plug-flow turning and throwing. During the fermentation process, negative pressure ventilation and dehumidification are carried out throughout the process, and aeration and compost turning are carried out intermittently, so that the internal temperature of the material is maintained at 55-70°C for more than 5 days; the residence time of the material in the composting and fermentation equipment is maintained for 5-7 days, and the material is discharged after the internal temperature drops below 40°C; S3. Use screening equipment to screen the materials output from the composting and fermentation equipment, collect the screened heat-releasing catalyst for recycling, and obtain composted organic fertilizer with a plant seed germination index greater than 70% and a moisture content less than 30%.

8. The composting process for accelerating the heating, dehydration and maturity of perishable garbage by chemical catalytic oxidation and heat release as claimed in claim 7, characterized in that: The pretreatment of the perishable garbage includes sorting, impurity removal, crushing and extrusion dehydration. The moisture content of the pretreated perishable garbage material is maintained at 65-75%, and the particle size is 3-5 cm. The feeding cycle of the biological drying equipment is daily. Before each day of feeding, 50%-80% of the dried material in the equipment on the previous day is transferred to the composting and fermentation equipment, and the remaining old material is retained and mixed with the new pretreated perishable garbage of the day.

9. The composting process for accelerating the heating, dehydration and maturity of perishable garbage by chemical catalytic oxidation and heat release as claimed in claim 7, characterized in that: During the aerobic fermentation process, the frequency of intermittent aeration is 5 to 15 minutes per hour, and the frequency of turning over is once a day.

10. The composting process for accelerating the heating, dehydration and maturity of perishable garbage by chemical catalytic oxidation and heat release as claimed in claim 7, characterized in that: When the heat-releasing catalyst is to be recycled, the heat-releasing catalyst screened out by the screening equipment needs to be cleaned and dried, and then added back into the bio-drying equipment for reuse.

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