Enzyme-heat combined intensified kitchen garbage biological drying method and device

Abstract

The application discloses a kind of enzyme-heat combined intensification kitchen garbage biological drying method and device, and add composite enzyme to kitchen garbage according to enzyme activity ratio, and add bacterial agent and conditioning agent, adjust moisture content and carbon-nitrogen ratio to form pile, start exogenous auxiliary heating, the temperature of pile in reaction device is heated, and continuous aeration is carried out using aeration pump, the temperature in pile is maintained for 1-2h after being separated from low temperature stage, then stop heating, re-start exogenous auxiliary heating when entering low temperature stage again, the moisture content of pile can be discharged when being reduced to 40% or less, complete a processing cycle, part of discharge is used as return material, and other discharge is used for resource utilization.The application can control the entire biological drying reduction process within 3-4 days, and the moisture content of discharge can be reduced to about 30% when the moisture content of kitchen garbage is 55-65%, the application can reduce the difficulty and cost of kitchen garbage collection and transportation processing, and the reduction product can be used for resource treatment in later period, with obvious environmental and economic benefits.

Description

Technical Field

[0001] This invention belongs to the field of kitchen waste treatment technology, and relates to biological drying treatment process, and in particular to an enzyme-thermal combined enhanced method and device for biological drying of kitchen waste. Background Technology

[0002] Kitchen waste refers to the waste generated in daily life, food processing, catering services, and unit catering activities. It includes discarded vegetable leaves, leftover food, fruit peels, eggshells, tea dregs, bones (chicken bones, fish bones, etc.), etc. Its main sources are family kitchens, restaurants, hotels, canteens, markets, and other industries related to food processing.

[0003] Bio-drying is a method for treating kitchen waste. Generally speaking, the traditional bio-drying cycle is 7-15 days. The drying effect is poor in the early and late stages of bio-drying, resulting in a long drying time. Even after extending the low-temperature residence time, the moisture content of the final product may still be higher than 45%, which not only has a low degree of stabilization, but is also far higher than the moisture content requirements for the preparation of RDF (<25%) or the moisture content requirements for spontaneous combustion of materials (<30%). Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide an enzyme-thermal combined enhanced biological drying method and apparatus for kitchen waste, so as to solve the problems of long biological drying cycle and low drying degree.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A method for enhancing the biological drying of kitchen waste using an enzyme-thermal combined approach includes the following steps:

[0007] Step 1: Add compound enzyme to kitchen waste according to the enzyme activity ratio.

[0008] Step 2: Add microbial agents and conditioning agents to the kitchen waste, adjust the moisture content and carbon-nitrogen ratio, mix evenly, load into a nylon filter to form a pile, and place into the reaction device.

[0009] Step 3: Start external auxiliary heating to raise the temperature of the reactor core and continuously aerate it using an aeration pump. Maintain the internal temperature of the core for 1-2 hours after it moves out of the low-temperature stage, then stop heating. The external auxiliary heating temperature is 30-37℃, and the low-temperature stage refers to the biological drying stage with a temperature ≤40℃.

[0010] Step 4: When the reactor enters the low-temperature stage again, its heat generation capacity is low. At this time, external auxiliary heating (at the same temperature as above) can be restarted to heat the reactor.

[0011] Step 5: Once the moisture content of the stockpile is reduced to below 40%, the material can be discharged, completing one processing cycle. Part of the discharged material is used for reprocessing, while the rest is used for resource utilization. The entire processing cycle takes 3-4 days.

[0012] Step 6: Replace the compound enzyme in Step 1 with the recycled material from Step 5, and repeat Steps 2 to 5 3 to 5 times, thereby running for a total of 4 to 6 processing cycles.

[0013] The kitchen waste described in this invention mainly includes typical kitchen waste, high-protein kitchen waste, high-fat kitchen waste, and canteen kitchen waste, etc. Among them, typical kitchen waste, high-protein kitchen waste, and high-fat kitchen waste are mainly composed of carbohydrates, proteins, and fats, respectively, while canteen kitchen waste is the remaining material after draining.

[0014] In one embodiment, to further improve the treatment effect, before step 1, non-degradable impurities such as plastics and shells are removed from the kitchen waste. Then, the kitchen waste is crushed to a particle size ≤ 5mm before proceeding to step 1. Smaller particle sizes allow for better contact with the enzymes, improving enzyme catalytic efficiency and increasing the contact area with microorganisms in the inoculant, which is beneficial for microbial metabolic activity. Correspondingly, in step 2, a 60-mesh nylon filter is used.

[0015] The composite enzyme described in this invention comprises carbohydrate enzyme, protease, and lipase, and the enzyme activity ratio is determined by the ratio of the activities of each enzyme in the composite enzyme. In the prior art, composite enzymes are prepared according to enzyme mass ratios. For example, when adding 8g of composite enzyme, with a mass ratio of 1:2:1, the masses of carbohydrate enzyme, protease, and lipase are 2g, 4g, and 2g, respectively. Assuming that the enzyme activities of 1g of carbohydrate enzyme, 1g of protease, and 1g of lipase are 5000U, 50000U, and 10000U, respectively, if the enzyme activity ratio is 1:2:1, then 4.7g, 0.9g, and 2.4g are added, respectively. Enzyme activity refers to the ability of an enzyme to catalyze a specific chemical reaction; under optimal conditions, the amount of enzyme required to convert 1 micromolar of substrate in 1 minute is one unit of enzyme activity (U). Therefore, the rate of enzymatic hydrolysis here is directly proportional to the enzyme activity of various complex enzymes, rather than the enzyme mass. Furthermore, the enzyme activity of the same enzyme varies between manufacturers. The optimal enzyme dosage and ratio obtained based on enzyme activity ratio is more universal and scientifically sound. Experiments have shown that, under the condition of adding the same mass of complex enzyme, the food waste hydrolysis rate (expressed as the amount of dissolved organic matter, i.e., soluble COD) based on enzyme activity ratio is more than 30% higher than that based on enzyme mass ratio.

[0016] In one embodiment, in step 1, the amount of compound enzyme added is 0.1-2 wt% of the wet weight of kitchen waste to enhance the degradation of organic matter. The enzyme activity ratio is set to a ratio of carbohydrate enzyme, protease, and lipase activity of 1:2:1. At this ratio, the best drying effect and efficiency can be obtained for various types of kitchen waste.

[0017] In one embodiment, the carbohydrate enzyme may be one or more of α-amylase, glucoamylase, arabinoxylanase, cellulase, and dextranase; when multiple enzymes are used, they are formulated with equal enzyme activity. The protease may be an acidic protease.

[0018] In one embodiment, the amount of microbial agent added is 5-10 wt% of the kitchen waste, and the amount of conditioning agent added is 10-20 wt% of the kitchen waste.

[0019] In one embodiment, the stockpile is aerated using an air pump to provide an aerobic atmosphere for aerobic microorganisms. The aeration flow rate is controlled at 0.5-1.5 L / kg based on the weight of the stockpile material using a flow meter. -1 ·min -1 .

[0020] In one embodiment, the types of microbial agents include, but are not limited to, EM microbial agents, Bacillus subtilis, etc., and a combination of multiple microbial agents may also be used; the conditioning agent is lignocellulose biomass such as sawdust, straw and corn cob, and one type or a combination of multiple conditioning agents may be used. The size of the conditioning agent is ≤10mm, which can adjust the moisture content of kitchen waste on the one hand, and act as a leavening agent to provide sufficient free space on the other hand.

[0021] In one embodiment, the external auxiliary heating is achieved through electric heating. This thermal assistance enhances the reduction effect of bio-drying, increasing the reduction rate and shortening the required time. When the temperature reaches 40-45°C, heating is restarted after a delay until the temperature drops again. The reactor's heat production capacity typically decreases after 72 hours, entering a low-temperature phase (temperature ≤40°C), at which point external heating is restarted. This invention heats the reactor during the low-temperature phase, contributing to increased reactor temperature, improved enzyme activity, and enhanced microbial metabolism. During the unheated phase, microbial degradation of organic matter generates bioheat to maintain the high-temperature phase of the reactor. Compared to traditional heating methods, the enzyme-heat combined approach is more energy-efficient.

[0022] In one embodiment, the pile is intermittently turned over during the entire bio-drying process to increase the uniformity of the pile, increase the contact area between enzymes and organic matter, the contact area between microorganisms and organic matter, and ensure a suitable free space in the pile. The turning frequency is 0.5-1 times / day.

[0023] In one embodiment, in step 5, the discharged material still contains the added compound enzyme, which can be recycled to replace the addition of the compound enzyme, thereby reducing costs and increasing efficiency. Generally speaking, when used as recycled material, the amount of recycled material is 60-80% of the discharged material.

[0024] In one embodiment, step 2 involves adding a conditioner to adjust the initial moisture content of the pile, controlling it to be between 55% and 65%. After running one treatment cycle (3-4 days) of enzyme-thermal combined biological drying, the moisture content drops to 30-40%, and the moisture removal rate is 65-80%.

[0025] This invention also provides an enzyme-thermal combined biological drying device for rapid treatment of household kitchen waste, comprising a biological drying chamber and a leachate collection chamber. The biological drying chamber is located above the leachate collection chamber, and the two are separated by a porous filter plate. The biological drying chamber is connected to a compound enzyme dosing device, a microbial agent dosing device, and a conditioner dosing device. Dry air is introduced through the side wall of the leachate collection chamber. A water-absorbing sponge is installed on the top of the biological drying chamber, and there is a space between the water-absorbing sponge and the material inside the chamber. The air outlet pipe of the biological drying chamber passes through the water-absorbing sponge, connecting the space to the outside space. The chamber wall of the biological drying chamber is an plexiglass partition, which is a hollow double-layer glass structure with an air layer in the hollow layer. A heating band is provided on the outer wall of the plexiglass partition and wrapped with an insulation layer. A temperature recorder and a stirring device are installed in the biological drying chamber.

[0026] The device of this invention incorporates an air layer, a heating belt, and insulation cotton outside the drying chamber. The air layer serves two purposes: first, it slows down the rate of heat transfer from the drying chamber to the outside when the temperature inside the chamber exceeds the temperature of the heating belt (30-37°C), thus reducing heat loss from biological processes; second, although the heating belt is temperature-controlled within a range of 30-37°C, its power requirement is generally high (rapid heating). When the heating belt is activated, the temperature typically rises rapidly, reaching 40-50°C, far exceeding the required set temperature. Without the buffering effect of the air layer, this rapid temperature increase would cause temperature fluctuations inside the drying chamber, adversely affecting microbial metabolism. The insulation cotton outside the heating belt further reduces heat loss from the heating belt to the outside air.

[0027] In one embodiment, the bio-drying chamber contains a 60-mesh nylon filter of equal size, and kitchen waste is fed into the filter to form a pile.

[0028] Furthermore, the kitchen waste containing enzymes, microbial agents, and conditioning agents is placed entirely into a filter bag, which is then placed into a drying chamber. The filter bag fits tightly against the drying chamber, with its bottom positioned above the porous filter plate. Using a filter bag also facilitates weighing and measurement during the discharge and return operations in steps 5 and 7 (the entire filter bag is weighed).

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] (1) This enzyme-thermal combined biological drying method for rapid reduction of kitchen waste involves adding enzymes to the biological drying system and using the efficient catalytic effect of enzymes to hydrolyze organic matter efficiently. This hydrolyzes complex macromolecular organic matter that is difficult for microorganisms to utilize into small molecule organic matter that is easy for microorganisms to utilize, creating a good metabolic and reproductive environment for microorganisms, accelerating microbial growth, enhancing microbial metabolic activities, and thus accelerating the generation of microbial biothermia, thereby achieving the removal of organic matter and water and achieving the purpose of enhancing the reduction effect of biological drying.

[0031] (2) This enzyme-heat combined biological drying method for rapid volume reduction of kitchen waste, by supplementing the biological drying system with external heating, can, on the one hand, increase the temperature of the pile, provide suitable conditions for enzyme hydrolysis, enhance enzyme activity, further improve the hydrolysis effect of organic matter, provide small molecule organic matter, enhance the metabolic intensity of microorganisms, and increase the amount of biological heat generated; on the other hand, the external auxiliary heat can directly raise the temperature of the pile, improve the moisture carrying capacity of the air, accelerate the conversion of moisture into water vapor, strengthen the moisture removal effect of biological drying, and further improve the volume reduction effect.

[0032] (3) The enzyme-heat combined biological drying method for rapid reduction of kitchen waste achieves a water removal effect similar to that of full heating by adopting a heating mode with heating at both ends, greatly reduces energy consumption, and improves the degradation of organic matter, thereby further improving the reduction degree. Attached Figure Description

[0033] Figure 1 This is a process flow diagram of the rapid reduction method for kitchen waste provided by the present invention.

[0034] Figure 2 This is a schematic diagram of the device structure used in this invention.

[0035] Figure 3 This is a schematic diagram illustrating the changes in the moisture content of kitchen waste over a long period of time, as shown in the embodiments of the present invention.

[0036] Figure 4 This is a schematic diagram illustrating the changes in the moisture removal rate of kitchen waste over a long period of time, as shown in the embodiments of the present invention.

[0037] In the diagram: 1. Air pump 2. Drying bottle 3. 5mm porous filter plate 4. Collection bottle 5. Temperature recorder 6. Flow meter 7. Absorbent sponge 8. Air layer 9. Insulation cotton 10. Serpentine condenser 11. Heating belt 12. Air inlet 13. Biological drying chamber 14. Leachate collection chamber 15. Acrylic glass partition 16. Air outlet. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0039] Unless otherwise specified, all methods used in the examples were conventional or performed according to techniques or conditions described in the literature in this field, or in accordance with the product instructions. Reagents and instruments used without specified manufacturers were all conventional products that could be purchased from legitimate channels.

[0040] The process flow diagram of the following embodiments is as follows: Figure 1 As shown, the device used is as follows Figure 2 As shown, the changes in moisture content during long-term enzyme-thermal bio-drying are as follows: Figure 3 As shown, the change in water removal rate is as follows: Figure 4 As shown.

[0041] refer to Figure 1 As shown, the enzyme-thermal combined enhanced bio-drying method for kitchen waste in this embodiment mainly includes the following steps:

[0042] (1) Collect kitchen waste from the canteen, drain off the free water, remove recalcitrant materials such as shells, and crush it using a meat grinder to break it down to less than 5mm for subsequent biological drying. Take 320g of the crushed kitchen waste for volume reduction. It is worth noting that this step is not mandatory. If crushing conditions are lacking, time requirements are not high, or the size of the kitchen waste itself is not excessively large, you can proceed directly to the next step.

[0043] (2) The compound enzyme was prepared according to the enzyme activity ratio. The enzyme activity ratio used was carbohydrate enzyme:protease:lipase = 1:2:1. This ratio is applicable to typical kitchen waste, high-protein kitchen waste, and high-fat kitchen waste, and has the widest range. The compound enzyme dosage was 1 wt% of the mass of the crushed kitchen waste. The microbial agent used was EM microbial agent, and the dosage was 5 wt% of the mass of the crushed kitchen waste. The compound enzyme and EM microbial agent were mixed evenly and then added to the crushed kitchen waste and mixed thoroughly.

[0044] (3) The conditioner used is wood chips, and the amount added is 15wt% of the mass of the crushed kitchen waste. The conditioner wood chips are added to the crushed kitchen waste and mixed evenly. The initial moisture content is adjusted to about 60%, and it is placed in a 60-mesh nylon filter and put into a biological drying device.

[0045] (4) Continuous aeration is performed using an aeration pump, and the ventilation volume is quantitatively controlled using a flow meter, adjusting the ventilation rate to 1 L·kg⁻¹. -1 ·min -1 The turning frequency of the biological drying process (1 time / day) is as follows: samples are taken every 24 hours to test the moisture content of the material, and the device and the material (placed in a 60-mesh sieve) are weighed.

[0046] (5) Heat the reactor body at 37°C using an external source, and combine this with the heat generated by the reactor body itself. Once the temperature reaches 42°C, maintain this temperature for 1-2 hours and then stop providing heat assistance to the reactor body.

[0047] (6) When the process reaches 72 hours, the temperature has dropped below 40°C. At this time, the external heating at 37°C is restarted to improve enzyme activity, microbial activity and biological drying effect through the external heating source.

[0048] (7) When the moisture content is below 40%, the material can be discharged. 100g of the discharged material is used for recycling. Repeating steps 1-7 allows for long-term operation.

[0049] (8) In this embodiment of the invention, the moisture content of the output material from enzyme-thermal combined drying with heating at both ends is similar to that from enzyme-thermal combined drying with heating throughout the process. Figure 3 and Figure 4 It can be seen that the efficiency is below 40%, and the moisture removal rate is also similar, around 70%. However, the energy consumption of heating at both ends is less than half that of heating throughout the process, which greatly saves energy.

[0050] Figure 2 The structure of the biological drying device of the present invention is shown, which mainly includes a biological drying chamber 13 and a leachate collection chamber 14. These two chambers can be independent or isolated within a single container. The biological drying chamber 13 is located above the leachate collection chamber 14, and the two are separated by a porous filter plate 5, the pore size of which is preferably about 5 mm. The volume ratio of the leachate collection chamber 14 to the biological drying chamber 13 is preferably 1:9 to 1:4.

[0051] The biological drying chamber 13 is connected to a compound enzyme dosing device, a microbial agent dosing device, and a conditioner dosing device, which are used to add compound enzymes, microbial agents, and conditioners to the kitchen waste inside, respectively.

[0052] Dry air is introduced into the side wall of the leachate collection chamber 14. This dry air can be generated by the air pump 1 and the drying bottle 2, and the flow rate is controlled by the flow meter 6. After being dried by the air pump 1 into the drying bottle 2, the air is regulated by the flow meter 6 and enters the upper part of the leachate collection chamber 14 through the air inlet 12, and then passes through the porous filter plate 3 into the biological drying chamber 13. After being dried by the drying bottle 2, the air's moisture-carrying capacity is enhanced.

[0053] A water-absorbing sponge 7 is installed on the top of the biological drying chamber 13. The water-absorbing material 7 can be a sponge, which serves to prevent condensate backflow. There is space between the water-absorbing sponge 7 and the material inside the chamber. The gas outlet pipe 16 of the biological drying chamber 13 passes through the water-absorbing sponge 7, connecting this space with the space outside the chamber. For gas collection and detection, the gas outlet pipe 16 can be connected to a serpentine condenser pipe 10 in the space outside the chamber. The gas exiting through the serpentine condenser pipe 10 then enters the gas collection bottle 4. The gas exiting the gas collection bottle 4 is discharged after passing through an auxiliary drying bottle 17.

[0054] A heating belt 11 is arranged around the biological drying chamber 13 to provide auxiliary heating. A temperature recorder 5 is installed in the biological drying chamber 13 for temperature monitoring. A stirring device is installed in the biological drying chamber 13 to achieve turning. Furthermore, the wall of the biological drying chamber 13 is made of plexiglass 15, which is a double-layer hollow glass with an air layer 8 in the middle. The air layer 8 plays a role in slowing down heat loss. The heating belt 11 is placed on the outer wall, and a layer of heat insulation cotton 9 is wrapped on the heating belt 11. Air carrying water vapor leaves the biological drying chamber 13 through the air outlet 16. After being condensed by the serpentine condenser 10, the condensate enters the collection bottle 4. The condensed gas passes through the auxiliary drying bottle 17 and is then discharged into the air.

[0055] Furthermore, the biological drying chamber 13 contains a 60-mesh nylon filter of the same size, which serves to ensure uniform air intake and facilitate easy feeding and discharging of materials. Kitchen waste is put into the filter to form a pile.

[0056] In summary, this invention can control the entire biological drying and volume reduction process within 3-4 days, and can operate when the moisture content of kitchen waste is 55-65%, with the output moisture content reduced to approximately 30%. This method reduces the difficulty and cost of waste collection and treatment, minimizes secondary pollution during waste collection, improves the living environment and urban appearance, and increases resource recovery rates. It features a short cycle, high efficiency, and low energy consumption. Furthermore, the reduced volume products can be further processed for resource recovery, generating significant environmental and economic benefits.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for enhancing the biological drying of kitchen waste using an enzyme-thermal combined approach, based on an apparatus for the rapid treatment of household kitchen waste using an enzyme-thermal combined biological drying approach, the apparatus comprising a biological drying chamber (13) and a leachate collection chamber (14), the biological drying chamber (13) being located above the leachate collection chamber (14), the two being separated by a porous filter plate (3), the biological drying chamber (13) being connected to a compound enzyme dosing device, a microbial agent dosing device, and a conditioner dosing device, dry air being introduced into the side wall of the leachate collection chamber (14), the biological drying chamber (13) being... A water-absorbing sponge (7) is installed at the top, and there is space between the water-absorbing sponge (7) and the material inside the chamber. The air outlet pipe (6) of the biological drying chamber (13) passes through the water-absorbing sponge (7) and connects the space with the space outside the chamber. The chamber wall of the biological drying chamber (13) is an organic glass partition (15). The organic glass partition (15) is a hollow double-layer glass structure, and the hollow layer is an air layer (8). The outer wall of the organic glass partition (15) is provided with a heating belt (11) and wrapped with a heat insulation layer (9). A temperature recorder (5) and a stirring device are installed in the biological drying chamber (13). Its features are, Includes the following steps: Step 1: Add a compound enzyme to the kitchen waste according to the enzyme activity ratio; the compound enzyme includes carbohydrate enzymes, proteases and lipases, and the enzyme activity ratio is the ratio of the activities of each type of enzyme in the compound enzyme. Step 2: Add microbial agents and conditioning agents to the kitchen waste, adjust the moisture content and carbon-nitrogen ratio, mix evenly, load into a nylon filter screen to form a pile, and place into the reaction device; Step 3: Start external auxiliary heating to heat the reactor body in the reactor and continuously aerate it with an aeration pump. After the internal temperature of the reactor body is out of the low temperature stage, maintain it for 1-2 hours and then stop heating. The external auxiliary heating temperature is 30-37℃, and the low temperature stage refers to the biological drying stage with a temperature ≤40℃. Step 4: When the reactor body enters the low-temperature stage again, restart the external auxiliary heating to heat the reactor body; Step 5: Once the moisture content of the stockpile is reduced to below 40%, the material can be discharged, completing one processing cycle. Part of the discharged material is used for recycling, while the rest is used for resource utilization. The entire processing cycle takes 3-4 days. Step 6: Replace the compound enzyme in Step 1 with the recycled material from Step 5, and repeat Steps 2 to 5 3 to 5 times.

2. The enzyme-thermal combined enhanced bio-drying method for kitchen waste according to claim 1, characterized in that, Before step 1, remove the non-degradable impurities from the kitchen waste, then crush the kitchen waste to a particle size of ≤5mm, and then proceed to step 1.

3. The enzyme-thermal combined enhanced bio-drying method for kitchen waste according to claim 1, characterized in that, In step 1, the amount of compound enzyme added is 0.1-2 wt% of the wet weight of kitchen waste, and the enzyme activity ratio is set to a ratio of carbohydrate enzyme, protease and lipase activity of 1:2:

1.

4. The enzyme-thermal combined enhanced bio-drying method for kitchen waste according to claim 1 or 3, characterized in that, The carbohydrate enzyme is one or more of α-amylase, glucoamylase, arabinoxylanase, cellulase, and glucanase. When there are multiple enzymes, they are prepared according to equal enzyme activities. The protease is an acidic protease.

5. The enzyme-thermal combined enhanced biological drying method for kitchen waste according to claim 1, characterized in that, The dosage of the microbial agent is 5-10 wt% of the kitchen waste, and the dosage of the conditioner is 10-20 wt% of the kitchen waste. The aeration flow rate, based on the weight of the pile material, is 0.5-1.5 L·kg⁻¹. -1 ·min -1 .

6. The enzyme-thermal combined enhanced bio-drying method for kitchen waste according to claim 1 or 5, characterized in that, The inoculant is EM inoculant and / or Bacillus subtilis; the conditioner is lignocellulose biomass with a size ≤10mm.

7. The enzyme-thermal combined enhanced bio-drying method for kitchen waste according to claim 1, characterized in that, The external auxiliary heating is achieved by electric heating. During the entire biological drying process, the pile is turned intermittently to increase the uniformity of the pile, increase the contact area between enzymes and organic matter, the contact area between microorganisms and organic matter, and ensure a suitable free space in the pile. The turning frequency is 0.5-1 times / day. In step 5, when used for return material, the amount of return material is 60-80% of the output material.

8. The enzyme-thermal combined enhanced bio-drying method for kitchen waste according to claim 1, characterized in that, In step 2, the conditioner is added to adjust the initial moisture content of the pile, controlling the moisture content to be between 55-65%, and the moisture removal rate after one cycle is between 65-80%.

9. The enzyme-thermal combined enhanced bio-drying method for kitchen waste according to claim 1, characterized in that, The biological drying chamber (13) contains a 60-mesh nylon filter of equal size, and kitchen waste is put into the filter to form a pile.

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