Method for preparing total-nutrient organic fertilizer from vitamin B12 mushroom dregs

Abstract

The invention relates to the technical field of fertilizers, in particular to a method for preparing a full-nutrient organic fertilizer from vitamin B12 mushroom dregs, which comprises the following steps: uniformly mixing the vitamin B12 mushroom dregs with household garbage; sequentially adding lotus leaf powder, weathered pulverized coal and oyster powder into the obtained mixture, adding lipase, a microbial agent and carbon nanotubes, stirring, and stacking to form a fermentation heap; in the initial stage of fermentation, carrying out first pile turning operation, and continuing fermentation for 3-5 days; after the primary fermentation is finished, stacking again, and carrying out secondary fermentation; and after the secondary fermentation is finished, drying and granulating the materials to obtain the full-nutrient organic fertilizer with uniform particles. According to the application, the bacillus thermophilus is directionally modified, and the lipolysis and antibacterial properties are enhanced by virtue of the nano-zinc oxide; during granulation, the unique binder ratio enhances the quality of fertilizer granules. A vacuum low-temperature dehydration technology is adopted, active ingredients of mushroom dregs are reserved, energy consumption is reduced, and the problems that traditional organic fertilizer is low in nutrient, poor in utilization rate, uneven in quality and the like are effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of fertilizers, and particularly to a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue. Background Art

[0002] With the growth of the global population and the improvement of living standards, the demand for agricultural products continues to grow, putting forward higher requirements not only in terms of quantity but also in terms of quality. This has prompted modern agriculture to develop in the direction of green, sustainable and efficient. In this process, the importance of high-quality organic fertilizers has become increasingly prominent. Organic fertilizers can improve the soil structure, enhance the water and fertilizer retention capacity of the soil, provide a better soil environment for the growth of crops, and thus increase the yield and quality of crops.

[0003] The resource utilization of agricultural waste has become an important topic. Among them, vitamin B12 bacterial residue, as a by-product of the biopharmaceutical industry, has long been regarded as waste for disposal, which not only causes waste of resources but also increases the environmental burden. However, the bacterial residue is rich in organic matter, trace elements and bioactive components, and has great potential to be converted into an efficient and environmentally friendly organic fertilizer. However, due to its complex composition, direct utilization faces technical challenges.

[0004] At the same time, the treatment of domestic waste is also a major problem in urban environmental governance. With the acceleration of the urbanization process, the output of domestic waste has increased sharply. Traditional landfill and incineration methods not only occupy a large amount of land resources but also may pose potential threats to the environment and human health. Therefore, exploring ways to recycle domestic waste and convert it into valuable resources is of great significance for promoting the sustainable development of cities.

[0005] In this context, the combined utilization of vitamin B12 bacterial residue and domestic waste has received extensive attention. Through scientific proportioning and advanced fermentation processes, these two kinds of waste can be converted into an efficient full-nutrient organic fertilizer. This measure not only solves the problem of waste treatment but also provides a high-quality fertilizer source for agricultural production. However, the organic fertilizers combined with vitamin B12 bacterial residue and domestic waste on the current market generally have problems such as low nutrient content, low utilization rate and uneven quality. Summary of the Invention

[0006] The present application provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue to solve the problems of low nutrient content, low utilization rate and uneven quality in the related art.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows: The present invention provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, comprising the following steps: (a) Mix the dehydrated vitamin B12 bacterial residue and the crushed domestic waste in a mass ratio of (3-5):(2-4) until uniform; (b) Add lotus leaf powder, weathered coal powder, oyster powder, and add lipase, microbial inoculum, and carbon nanotubes to the obtained mixture, and stir and react for 2-4 hours at a temperature range of 30-40 °C by a high-speed stirring device. After ensuring that all components are fully and uniformly mixed, stack them to form a fermentation pile; (c) In the initial stage of fermentation, keep the temperature in the fermentation pile at 30-40 °C for 3-5 days, monitor the temperature during this period, and when the temperature rises to 50-60 °C, perform the first turning operation, and then continue to ferment for 3-5 days, maintaining the temperature in the pile at 50-60 °C during this period; (d) After the first fermentation is completed, break up the fermented materials and adjust their water content to 50%-60%, stack them again to form a fermentation pile, and control the temperature in the pile within the range of 25-35 °C for secondary fermentation, and the fermentation duration is 7-10 days; (e) After the secondary fermentation is completed, dry the materials to reduce their water content to less than 15%, and then remove the incompletely decomposed impurities through a screening device to obtain a full-nutrient organic fertilizer with uniform particles.

[0008] Further, the addition amounts of the lotus leaf powder, the weathered coal powder, and the oyster powder in step (b) are 5%-10%, 10%-20%, and 5%-15% of the total mass of the mixture, respectively.

[0009] Further, the addition amounts of the lipase, the microbial inoculum, and the carbon nanotubes in step (b) are 0.1%-0.5%, 0.5%-2%, and 0.01%-0.1% of the total mass of the mixture, respectively.

[0010] Further, the lipase is Bacillus thermophilus, and the microbial inoculum includes Bacillus subtilis, lactic acid bacteria, and yeast.

[0011] Further, before adding the lipase, it includes: performing directed modification on the Bacillus thermophilus, wherein a nano-zinc oxide-amino acid fragment is introduced at positions 150-160 of the amino acid sequence of the Bacillus thermophilus.

[0012] Further, in step (c), a temperature sensor is used to monitor the temperature in the fermentation pile, and the temperature sensors are evenly distributed in the upper, middle, and lower layers of the fermentation pile, with at least two sensors provided in each layer.

[0013] Further, in step (d), limestone is added during the fermentation process to adjust the pH value.

[0014] Further, in step (a), the dehydrated vitamin B12 bacterial residue is dehydrated by a vacuum low-temperature dehydration technique, with the dehydration temperature controlled at 40-50°C and the vacuum degree at -0.06--0.08 MPa.

[0015] Further, in step (e), the dried material is granulated for the second time, and a binder accounting for 0.5%-1% of the total mass of the material is added during the granulation process.

[0016] Further, the binder is composed of wood-based cellulose, chitosan, and sodium alginate mixed in a mass ratio of 2:1:0.5.

[0017] The beneficial effects obtained by the present invention are as follows: 1. The present invention prepares a full-nutrient organic fertilizer from vitamin B12 bacterial residue, and conducts directional modification on Bacillus thermophilus, introducing a nano-zinc oxide-amino acid fragment into positions 150-160 of its amino acid sequence, changing the amino acid residue composition and spatial conformation of the active center of the lipase of Bacillus thermophilus. Nano-zinc oxide has unique quantum size effect and surface effect, and can form a more stable transition state complex with substrate molecules. Specifically, after the active center of lipase binds to fat molecules, through an acid-base catalysis mechanism, the ester bond of the fat molecules undergoes a hydrolysis reaction. The presence of nano-zinc oxide enhances the electron cloud density of the active center, enabling the histidine in the active center to more effectively attack the ester bond, reducing the activation energy of the reaction, and thus more efficiently catalyzing the decomposition of fat substances into glycerol and fatty acids, further providing energy and nutrient substrates for the growth and metabolism of microorganisms; at the same time, nano-zinc oxide has antibacterial properties, and the zinc ions on its surface can bind to biological macromolecules such as proteins and enzymes on the cell membranes of harmful microorganisms, destroying the integrity and permeability of the cell membranes, resulting in the leakage of intracellular substances, thereby inhibiting the growth of harmful microorganisms during the fermentation process, ensuring that the fermentation process proceeds in a relatively pure microbial environment, being conducive to the growth and reproduction of beneficial microorganisms, increasing the content and activity of beneficial microorganisms in the organic fertilizer, and further improving the quality and fertilizer efficiency of the organic fertilizer; 2. The present invention combines vitamin B12 bacterial residue with domestic waste, opening up a new path for the resource utilization of waste and significantly reducing the degree of environmental pollution. Vitamin B12 bacterial residue is rich in organic substances such as proteins, polysaccharides, nucleic acids, as well as various trace elements such as zinc, iron, and manganese, and also contains some bioactive enzymes and metabolites. The organic components in domestic waste, such as carbohydrates and proteins in kitchen waste, complement the components in the bacterial residue. During the subsequent fermentation process, microorganisms use these organic substances as carbon sources and nitrogen sources, and through biochemical reactions, convert them into nutrients such as humus, amino acids, and polypeptides that can be absorbed and utilized by plants, avoiding soil and groundwater pollution caused by traditional landfill methods and harmful gas emissions generated by incineration methods, and realizing the recycling of resources; 3. Secondly, the alkaloids and organic substances contained in lotus leaf powder can undergo hydrolysis, oxidation and other reactions under the action of microorganisms, which can change the permeability of the cell membrane of soil microorganisms, regulate the soil microbial community structure, and promote the growth and reproduction of beneficial microorganisms such as Bacillus subtilis and Lactobacillus. At the same time, the organic substances provide an additional carbon source for the microorganisms. Through the metabolic action of the microorganisms, they are converted into carbon dioxide, water and energy, providing power for the life activities of the microorganisms; weathered coal powder has a special layered structure, a large specific surface area, and a large number of active sites on the surface that can undergo ion exchange adsorption and chemical adsorption with nutrients such as ammonium ions and phosphate ions in the fertilizer. Specifically, ammonium ions are adsorbed on the negatively charged sites on the surface of weathered coal powder through electrostatic attraction to form a relatively stable adsorbed ammonium. In the soil, when the nutrient concentration around the plant roots decreases, these adsorbed nutrients will be slowly released for the plants to absorb and utilize, thus reducing the loss of nutrients and significantly improving the fertilizer utilization rate; oyster powder is rich in mineral components such as calcium carbonate and calcium phosphate, as well as a small amount of organic substances such as proteins and amino acids. During the fermentation process, calcium carbonate undergoes a chemical reaction under the action of acidic substances produced by microbial metabolism, gradually releasing calcium ions to provide calcium nutrition for the plants. At the same time, the organic substances in oyster powder can also be decomposed and utilized by microorganisms and participate in the nutrient conversion process of organic fertilizers; 4. At the same time, carbon nanotubes have a unique one-dimensional nanostructure, with a very large specific surface area and excellent adsorption properties. In the fermentation system, it can adsorb small molecule organic substances, metal ions, etc. decomposed from vitamin B12 bacterial residues and domestic waste, and enrich these substances on its surface, providing a highly concentrated nutrient microenvironment for microorganisms. At the same time, the surface properties of carbon nanotubes can promote the attachment and growth of microorganisms. Some functional groups on its tube wall can interact with biological macromolecules such as proteins and polysaccharides on the surface of microbial cells, enhancing the affinity between microorganisms and carbon nanotubes, and facilitating the formation of a stable biofilm on its surface. In addition, carbon nanotubes also have good electron conduction properties. During the microbial metabolism process, many oxidation-reduction reactions are involved, and electron transfer plays a key role in these reactions. Carbon nanotubes can serve as a bridge for electron transfer, accelerating the electron transfer process between microorganisms and between microorganisms and the surrounding environment, promoting the progress of oxidation-reduction reactions, thus improving the fermentation efficiency and accelerating the conversion and synthesis rate of nutrients; 4. The present invention conducts secondary granulation and adds a binder during the granulation process. Among them, the long-chain structure of lignocellulose can penetrate between fertilizer particles, acting as a bridge to connect numerous small fertilizer particles together, increasing the internal cohesion between particles, and thus improving the strength and stability of fertilizer particles. Chitosan molecules contain a large number of amino and hydroxyl groups, and have good hydrophilicity and cationic properties. Its cationic properties enable chitosan to have an electrostatic attraction with the negatively charged groups on the surface of fertilizer particles, further enhancing the binding force with fertilizer particles. At the same time, chitosan can form a viscous colloid in aqueous solution, filling the gaps between fertilizer particles, which not only increases the viscosity between particles but also prevents the relative sliding between particles, contributing to the formation of a tight and stable particle structure. Sodium alginate undergoes a cross-linking reaction with divalent cations such as calcium ions to form a three-dimensional network structure gel, greatly improving the forming effect and anti-crushing ability of fertilizer particles, and being able to better bind fertilizer particles together to form a full-nutrient organic fertilizer with uniform particles, appropriate strength, and high stability; 5. The vacuum low-temperature dehydration technology is adopted in the preparation method of the present invention, which can effectively retain the bioactive components in the bacterial residue, providing more nutrients and biological catalysts for the subsequent fermentation process. At the same time, by precisely controlling the vacuum degree and temperature range, the dehydration efficiency is optimized, the equipment operation time is reduced, and the energy consumption cost is further reduced. Brief Description of the Drawings

[0018] The above and / or additional aspects and advantages of the present application will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, where: Figure 1 is a flowchart of a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue provided in an embodiment of the present invention; Figure 2 is a schematic distribution diagram of temperature sensors provided in an embodiment of the present invention. Detailed Embodiments

[0019] The following specific examples illustrate the technical solutions of the present invention. It should be understood that one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combined steps or the insertion of other method steps between these clearly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. Moreover, unless otherwise specified, the numbers of each method step are only convenient tools for identifying each method step, rather than limiting the arrangement order of each method step or the scope of the present invention that can be implemented. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope that the present invention can implement.

[0020] To better understand the above technical solution, the exemplary embodiments of the present invention will be described in more detail below. Although the exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present invention can be more thoroughly understood and the scope of the present invention can be fully conveyed to those skilled in the art.

[0021] A method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue according to an embodiment of the present application will be described below with reference to the accompanying drawings. In view of the problem of low utilization rate mentioned in the above background technology, the present application provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue. In this method, nano-zinc oxide-amino acid fragments are introduced by directed transformation of Bacillus thermophilus to enhance lipase activity and endow antibacterial properties. The vitamin B12 bacterial residue is combined with domestic waste to realize the resource utilization of waste. At the same time, functional auxiliaries such as lotus leaf powder, weathered coal powder and oyster powder are added to regulate the soil microbial community, improve the fertilizer nutrient utilization rate and provide mineral nutrition. In addition, the adsorption and electron conduction properties of carbon nanotubes are used to promote the growth and fermentation efficiency of microorganisms, and the strength and stability of fertilizer particles are improved by using a secondary granulation process and a binder. Finally, a vacuum low-temperature dehydration technology is adopted to effectively retain the bioactive components in the bacterial residue, optimize the dehydration efficiency, reduce the energy consumption cost, and successfully convert the vitamin B12 bacterial residue and domestic waste into a high-efficiency, stable and environmentally friendly full-nutrient organic fertilizer. Thus, the problems of low nutrient content, low utilization rate and uneven quality in the related technology are solved.

[0022] Specifically, Figure 1 A method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue provided by an embodiment of the present application.

[0023] As Figure 1 shown, the method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue includes the following steps: In step S101, the dehydrated vitamin B12 bacterial residue and the crushed domestic waste are mixed in a mass ratio of (3-5):(2-4) until uniform.

[0024] It can be understood that in the embodiment of the present application, the vitamin B12 bacterial residue and the domestic waste are mixed in proportion. This mixing process needs to be carried out continuously until the two materials are uniformly mixed together to form a uniform mixture, preparing for the subsequent fermentation process.

[0025] In the embodiment of the present application, the dehydrated vitamin B12 bacterial residue adopts a vacuum low-temperature dehydration technology, the dehydration temperature is controlled at 40-50 °C, and the vacuum degree is -0.06--0.08 MPa.

[0026] Among them, the vacuum low-temperature dehydration technology is a technology that accelerates the evaporation of moisture in substances by creating a vacuum environment at a relatively low temperature.

[0027] It can be understood that before mixing in the embodiments of the present application, the vitamin B12 bacterial residue has been dehydrated by the vacuum low-temperature dehydration technology, ensuring that the moisture in the bacterial residue is effectively removed while retaining the bioactive components therein, providing favorable conditions for the subsequent mixing and fermentation processes.

[0028] In step S102, lotus leaf powder, weathered coal powder, oyster powder are sequentially added to the obtained mixture, and lipase, microbial inoculum and carbon nanotubes are added. Stirring reaction is carried out for 2 - 4 hours at a temperature range of 30 - 40 °C by a high-speed stirring device. After ensuring that all components are fully and evenly mixed, a fermentation pile is formed by stacking.

[0029] It can be understood that in the fermentation process of the embodiments of the present application, there is a delicate synergistic effect between auxiliary materials such as lotus leaf powder, weathered coal powder, oyster powder, carbon nanotubes and the microbial inoculum.

[0030] Among them, alkaloids such as nuciferine and pronuciferine contained in lotus leaf powder, as well as rich organic substances such as polysaccharides and flavonoids, undergo hydrolysis, oxidation and other reactions under the action of microorganisms. Alkaloids such as nuciferine can change the permeability of the cell membrane of soil microorganisms, regulate the soil microbial community structure, and promote the growth and reproduction of beneficial microorganisms such as Bacillus subtilis and Lactobacillus. At the same time, its organic substances such as polysaccharides provide additional carbon sources for microorganisms, which are converted into carbon dioxide, water and energy through the metabolic action of microorganisms, providing power for the life activities of microorganisms.

[0031] Weathered coal powder has a special layered structure, a large specific surface area, and a large number of active sites on the surface. These active sites can carry out ion exchange adsorption and chemical adsorption with nutrients such as ammonium ions and phosphate ions in fertilizers.

[0032] For example, ammonium ions are adsorbed on the negatively charged sites on the surface of weathered coal powder through electrostatic attraction to form relatively stable adsorbed ammonium. In the soil, when the nutrient concentration around the plant roots decreases, these adsorbed nutrients will be slowly released for the plants to absorb and utilize, thereby reducing the loss of nutrients and significantly improving the utilization rate of fertilizers.

[0033] Oyster powder is rich in mineral components such as calcium carbonate and calcium phosphate, as well as a small amount of organic substances such as proteins and amino acids. During the fermentation process, calcium carbonate undergoes a chemical reaction under the action of acidic substances produced by microbial metabolism, gradually releasing calcium ions to provide calcium nutrition for plants. At the same time, the organic substances in oyster powder can also be decomposed and utilized by microorganisms and participate in the nutrient conversion process of organic fertilizers.

[0034] Carbon nanotubes have a unique one-dimensional nanostructure, with a large specific surface area and excellent adsorption properties. In a fermentation system, it can adsorb small-molecule organic substances, metal ions, etc. decomposed from vitamin B12 bacterial residues and domestic waste, enriching these substances on its surface and providing a highly concentrated nutrient microenvironment for microorganisms. At the same time, the surface properties of carbon nanotubes can promote the attachment and growth of microorganisms. Some functional groups on its tube wall can interact with biological macromolecules such as proteins and polysaccharides on the surface of microbial cells, enhancing the affinity between microorganisms and carbon nanotubes and facilitating the formation of a stable biofilm on its surface. In addition, carbon nanotubes also have good electron conduction properties. During the microbial metabolism process, many oxidation-reduction reactions are involved, and electron transfer plays a key role in these reactions. Carbon nanotubes can serve as a bridge for electron transfer, accelerating the electron transfer process between microorganisms and between microorganisms and the surrounding environment, promoting the progress of oxidation-reduction reactions, thereby improving the fermentation efficiency and accelerating the conversion and synthesis rate of nutrients.

[0035] In the embodiments of the present application, the addition amounts of lotus leaf powder, weathered coal powder, and oyster powder are 5%-10%, 10%-20%, and 5%-15% of the total mass of the mixture, respectively.

[0036] In the embodiments of the present application, the addition amounts of lipase, microbial inoculum, and carbon nanotubes are 0.1%-0.5%, 0.5%-2%, and 0.01%-0.1% of the total mass of the mixture, respectively.

[0037] Among them, the lipase is Bacillus thermophilus, and the microbial inoculum includes Bacillus subtilis, lactic acid bacteria, and yeast.

[0038] It is understandable that in the embodiments of the present application, different strains such as Bacillus subtilis, lactic acid bacteria, and yeast in the microbial inoculum cooperate synergistically. Bacillus subtilis can secrete various extracellular enzymes, such as amylase, protease, lipase, etc. Amylase can decompose polysaccharides such as starch into monosaccharides such as glucose, protease decomposes proteins into amino acids and polypeptides, and lipase decomposes fats into glycerol and fatty acids. These small-molecule substances are easily utilized by other microorganisms, providing rich nutrient substrates for the growth of lactic acid bacteria and yeast. Lactic acid bacteria produce lactic acid during fermentation, reducing the pH value of the fermentation environment and inhibiting the growth of harmful microorganisms (such as Escherichia coli, Salmonella, etc.). Yeast converts organic substances such as sugars into carbon dioxide, alcohol, and energy through aerobic and anaerobic respiration processes, while promoting the oxidation-reduction reaction of substances in the fermentation system and accelerating the transformation and synthesis of nutrients. The combined action of these microorganisms enables the macronutrients such as nitrogen, phosphorus, and potassium, as well as various trace elements in the organic fertilizer, to be converted into forms more easily absorbed by plant roots, such as amino acid chelate state and humic acid combined state, through a series of complex biochemical reactions, thus fully meeting the diverse needs of plant growth and significantly improving the yield and quality of crops.

[0039] In the embodiments of the present application, before adding lipase, it includes: performing directed modification on Bacillus thermophilus, wherein a nano-zinc oxide-amino acid fragment is introduced at positions 150-160 of the amino acid sequence of Bacillus thermophilus.

[0040] It is understandable that in the embodiments of the present application, Bacillus thermophilus is subjected to directed modification, and a nano-zinc oxide-amino acid fragment is introduced at positions 150-160 of its amino acid sequence, changing the amino acid residue composition and spatial conformation of the active center of the lipase of Bacillus thermophilus. Nano-zinc oxide has unique quantum size effect and surface effect, and can form a more stable transition state complex with substrate molecules. Specifically, after the active center of lipase binds to fat molecules, through the acid-base catalysis mechanism, the ester bond of the fat molecule undergoes hydrolysis reaction. The presence of nano-zinc oxide enhances the electron cloud density of the active center, enabling the histidine in the active center to more effectively attack the ester bond, reducing the activation energy of the reaction, and thus more efficiently catalyzing the decomposition of fat substances into glycerol and fatty acids, further providing energy and nutrient substrates for the growth and metabolism of microorganisms; at the same time, nano-zinc oxide has antibacterial properties, and the zinc ions on its surface can bind to biological macromolecules such as proteins and enzymes on the cell membrane of harmful microorganisms, destroying the integrity and permeability of the cell membrane, resulting in the leakage of intracellular substances, thereby inhibiting the growth of harmful microorganisms during fermentation, ensuring that the fermentation process proceeds in a relatively pure microbial environment, being conducive to the growth and reproduction of beneficial microorganisms, increasing the content and activity of beneficial microorganisms in the organic fertilizer, and further improving the quality and fertilizer efficiency of the organic fertilizer.

[0041] In step S103, at the initial stage of fermentation, the temperature in the fermentation pile is maintained at 30-40°C for 3-5 days, during which the temperature is monitored. When the temperature rises to 50-60°C, the first pile turning operation is performed, and then fermentation is continued for 3-5 days, during which the temperature in the pile is maintained at 50-60°C.

[0042] Among them, turning the pile refers to the operation of regularly turning or stirring the materials in the fermentation pile during the fermentation process.

[0043] It is understandable that, as the fermentation proceeds in the embodiment of the present application, an anaerobic area will gradually form inside the fermentation pile, resulting in limited microbial growth. Turning the pile can fully expose the materials in the pile to the air, break the anaerobic environment, provide sufficient oxygen for aerobic microorganisms, and promote their large-scale reproduction and metabolic activities. On the other hand, turning the pile can make the temperature distribution in the fermentation pile more uniform. Due to the uneven heat generation during the fermentation process, local high temperature or low temperature areas may appear in the pile, which will affect the fermentation effect. By turning the pile, the materials in the high temperature area and the low temperature area can be mixed, so that the overall temperature is stabilized in a suitable fermentation range, maintaining the best environment for microbial growth. At the same time, turning the pile can also promote the dissipation of waste gas and adjust the humidity in the pile. Waste gas such as carbon dioxide will be produced during the fermentation process. If it is not discharged in time, it will affect the respiration of microorganisms; and humidity is also crucial to the growth and metabolism of microorganisms. Turning the pile helps to maintain a suitable humidity and further optimize the fermentation conditions. After turning the pile, continue fermentation for 3-5 days, maintaining the temperature in the pile at 50-60℃. The high temperature environment at this stage is conducive to the activity of thermophilic microorganisms, which can decompose some organic substances that are difficult to degrade, such as lignin, further promote the composting of materials, and increase the content of humus in organic fertilizer, thereby improving the quality and fertilizer efficiency of organic fertilizer and making it more conducive to plant growth.

[0044] In the embodiments of the present application, Figure 2 As shown, temperature sensors are used to monitor the temperature in the fermentation pile. The temperature sensors are evenly distributed in the upper, middle and lower layers of the fermentation pile, and at least two sensors are set on each layer.

[0045] In step S104, after the first fermentation is completed, the fermented materials are dispersed and the water content is adjusted to 50%-60%, and then piled up again to form a fermentation pile. The temperature in the pile is controlled within the range of 25-35°C for secondary fermentation, and the fermentation duration is 7-10 days.

[0046] Among them, limestone is added to adjust the pH value during the fermentation process.

[0047] It is understandable that after the first fermentation of the embodiments of the present application, the materials are broken up, the water content is adjusted, and then piled up to form a new fermentation pile, and the second fermentation is carried out for 7-10 days within the range of 25-35 °C. During this period, limestone is added to adjust the PH value to enhance the microbial activity, promote the full decomposition of organic matter, and optimize the quality and stability of the fermentation products.

[0048] In step S105, after the second fermentation is completed, the materials are dried to reduce the water content to less than 15%. Subsequently, the incompletely decomposed impurities are removed by screening equipment to obtain a fully nutritious organic fertilizer with uniform particles.

[0049] It is understandable that after the second fermentation of the embodiments of the present application, drying treatment is carried out to reduce the water content of the materials to less than 15% to ensure the stability and quality of the organic fertilizer during storage and transportation. Subsequently, a screening device is used to carefully screen the dried materials, effectively removing incompletely decomposed impurities and particles that are too large or too small, so as to obtain a fully nutritious organic fertilizer with uniform particles and high purity. This not only improves the quality of the organic fertilizer but also ensures its uniformity and effectiveness in farmland applications, providing a high-quality source of organic fertilizer for agricultural production.

[0050] In the embodiments of the present application, the dried materials are subjected to secondary granulation, and a binder accounting for 0.5%-1% of the total mass of the materials is added during the granulation process.

[0051] Among them, the binder is a mixture of lignocellulose, chitosan and sodium alginate in a mass ratio of 2:1:0.5.

[0052] It is understandable that the embodiments of the present application carry out secondary granulation, and a binder is added during the granulation process. Among them, the long-chain structure of lignocellulose can penetrate between the fertilizer particles and play a bridging role, connecting many small fertilizer particles together, increasing the internal cohesion between the particles, and thus improving the strength and stability of the fertilizer particles. The chitosan molecule contains a large number of amino and hydroxyl groups, and has good hydrophilicity and cationic properties. Its cationic properties enable chitosan to have an electrostatic attraction with the negatively charged groups on the surface of the fertilizer particles, further enhancing the binding force with the fertilizer particles. At the same time, chitosan can form a viscous colloid in aqueous solution, filling the gaps between the fertilizer particles. This not only increases the viscosity between the particles but also prevents the relative sliding between the particles, helping to form a tight and stable particle structure. Sodium alginate undergoes a cross-linking reaction with divalent cations such as calcium ions to form a three-dimensional network structure gel, greatly improving the forming effect and anti-crushing ability of the fertilizer particles, and being able to better combine the fertilizer particles together to form a fully nutritious organic fertilizer with uniform particles, appropriate strength and high stability.

[0053] A method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue is proposed according to the present application. By genetically engineering Bacillus thermophilus to introduce nano-zinc oxide-amino acid fragments to enhance lipase activity and endow antibacterial properties, the resource utilization of waste is realized by combining vitamin B12 bacterial residue with domestic waste. At the same time, functional auxiliaries such as lotus leaf powder, weathered coal powder and oyster powder are added to regulate the soil microbial community, improve the fertilizer nutrient utilization rate and provide mineral nutrition. In addition, the adsorption and electron conduction properties of carbon nanotubes are used to promote the growth and fermentation efficiency of microorganisms, and the strength and stability of fertilizer particles are improved by using a secondary granulation process and a binder. Finally, a vacuum low-temperature dehydration technology is adopted to effectively retain the bioactive components in the bacterial residue, optimize the dehydration efficiency, reduce the energy consumption cost, and successfully convert the vitamin B12 bacterial residue and domestic waste into a high-efficiency, stable and environmentally friendly full-nutrient organic fertilizer. Thus, the problems of low nutrient content, low utilization rate and uneven quality in the related technologies are solved.

[0054] The present invention will be further described below in conjunction with the following embodiments.

[0055] Example 1 The present invention provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, comprising the following steps: (a) mixing the dehydrated vitamin B12 bacterial residue and the crushed domestic waste in a mass ratio of 3:2 until uniform; (b) sequentially adding lotus leaf powder, weathered coal powder, oyster powder, and adding lipase, microbial inoculum and carbon nanotubes to the obtained mixture, and stirring and reacting for 2-4 hours at a temperature range of 30-40 °C by a high-speed stirring device. After ensuring that all components are fully and uniformly mixed, a fermentation pile is formed by piling up; (c) in the initial stage of fermentation, the temperature inside the fermentation pile is maintained at 30-40 °C for 3-5 days. During this period, the temperature is monitored. When the temperature rises to 50-60 °C, the first turning operation is carried out, and then fermentation continues for 3-5 days, during which the temperature inside the pile is maintained at 50-60 °C; (d) after the first fermentation is completed, the fermented material is broken up and its water content is adjusted to 50%-60%, and a fermentation pile is formed again, and the second fermentation is carried out at a temperature range of 25-35 °C inside the pile, and the fermentation duration is 7-10 days; (e) after the second fermentation is completed, the material is dried to make its water content drop below 15%, and then the incompletely decomposed impurities are removed by a screening device to obtain a full-nutrient organic fertilizer with uniform particles.

[0056] In the embodiment of the present application, the addition amounts of lotus leaf powder, weathered coal powder and oyster powder in step (b) are 5%, 10% and 5% of the total mass of the mixture respectively.

[0057] In the embodiment of the present application, the addition amounts of lipase, microbial inoculum and carbon nanotubes in step (b) are 0.1%, 0.5% and 0.01% of the total mass of the mixture respectively.

[0058] In the embodiment of the present application, the lipase is Bacillus thermophilus, and the microbial inoculum includes Bacillus subtilis, lactic acid bacteria, and yeast.

[0059] In the embodiment of the present application, before adding the lipase, it includes: performing directed modification on Bacillus thermophilus, wherein a nano-zinc oxide-amino acid fragment is introduced at positions 150-160 of the amino acid sequence of Bacillus thermophilus.

[0060] In the embodiment of the present application, in step (c), a temperature sensor is used to monitor the temperature inside the fermentation heap. The temperature sensors are evenly distributed in the upper, middle, and lower layers of the fermentation heap, and at least two sensors are arranged in each layer.

[0061] In the embodiment of the present application, in step (d), limestone is added during the fermentation process to adjust the pH value.

[0062] In the embodiment of the present application, in step (a), the dehydrated vitamin B12 bacterial residue adopts a vacuum low-temperature dehydration technology, the dehydration temperature is controlled at 40-50°C, and the vacuum degree is -0.06--0.08 MPa.

[0063] In the embodiment of the present application, in step (e), the dried material is subjected to secondary granulation, and a binder accounting for 0.5% of the total mass of the material is added during the granulation process.

[0064] In the embodiment of the present application, the binder is composed of wood-based cellulose, chitosan, and sodium alginate mixed in a mass ratio of 2:1:0.5.

[0065] Example 2 The present invention provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, comprising the following steps: (a) Mix the dehydrated vitamin B12 bacterial residue and the crushed domestic waste in a mass ratio of 3.5:2.5 until uniform; (b) Add lotus leaf powder, weathered coal powder, oyster powder, and add lipase, microbial inoculum and carbon nanotubes to the obtained mixture, and stir and react for 2-4 hours at a temperature range of 30-40 °C through a high-speed stirring device. After ensuring that all components are fully and uniformly mixed, stack them to form a fermentation pile; (c) In the initial stage of fermentation, keep the temperature in the fermentation pile at 30-40 °C for 3-5 days, monitor the temperature during this period, and when the temperature rises to 50-60 °C, perform the first turning operation, and then continue to ferment for 3-5 days, maintaining the temperature in the pile at 50-60 °C during this period; (d) After the first fermentation is completed, break up the fermentation materials and adjust their water content to 50%-60%, and stack them again to form a fermentation pile, and control the temperature in the pile at 25-35 °C for secondary fermentation, and the fermentation duration is 7-10 days; (e) After the secondary fermentation is completed, dry the materials to reduce their water content to less than 15%, and then remove the incompletely decomposed impurities through a screening device to obtain a full-nutrient organic fertilizer with uniform particles.

[0066] In the embodiment of the present application, the addition amounts of lotus leaf powder, weathered coal powder, and oyster powder in step (b) are 6%, 12%, and 8% of the total mass of the mixture, respectively.

[0067] In the embodiment of the present application, the addition amounts of lipase, microbial inoculum and carbon nanotubes in step (b) are 0.2%, 0.7%, and 0.03% of the total mass of the mixture, respectively.

[0068] In the embodiment of the present application, the lipase is Bacillus stearothermophilus, and the microbial inoculum includes Bacillus subtilis, Lactobacillus and Saccharomyces cerevisiae.

[0069] In the embodiment of the present application, before adding lipase, it includes: performing directed modification on Bacillus stearothermophilus, wherein a nano-zinc oxide-amino acid fragment is introduced at positions 150-160 of the amino acid sequence of Bacillus stearothermophilus.

[0070] In the embodiment of the present application, in step (c), a temperature sensor is used to monitor the temperature in the fermentation pile, and the temperature sensors are evenly distributed in the upper, middle and lower layers of the fermentation pile, and at least two sensors are set in each layer.

[0071] In the embodiment of the present application, in step (d), limestone is added during the fermentation process to adjust the PH value.

[0072] In the embodiment of the present application, in step (a), the dehydrated vitamin B12 bacterial residue adopts vacuum low-temperature dehydration technology, the dehydration temperature is controlled at 40-50 °C, and the vacuum degree is -0.06--0.08 MPa.

[0073] In an embodiment of the present application, in step (e), the dried material is subjected to secondary granulation, and a binder accounting for 0.6% of the total mass of the material is added during the granulation process.

[0074] In an embodiment of the present application, the binder is a mixture of lignocellulose, chitosan and sodium alginate in a mass ratio of 2:1:0.5.

[0075] Example 3 The present invention provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, comprising the following steps: (a) mixing the dehydrated vitamin B12 bacterial residue and the pulverized domestic waste in a mass ratio of 4:3 until uniform; (b) successively adding lotus leaf powder, weathered coal powder, oyster powder, and adding lipase, microbial inoculum and carbon nanotubes to the obtained mixture, and stirring and reacting for 2-4 hours under the condition that the temperature range is 30-40 °C by a high-speed stirring device, and after ensuring that all components are fully and uniformly mixed, piling up to form a fermentation pile; (c) in the initial stage of fermentation, maintaining the temperature in the fermentation pile at 30-40 °C for 3-5 days, monitoring the temperature during this period, and when the temperature rises to 50-60 °C, performing the first turning operation, and then continuing to ferment for 3-5 days, maintaining the temperature in the pile at 50-60 °C during this period; (d) after the first fermentation is completed, dispersing the fermented material and adjusting its water content to 50%-60%, piling up again to form a fermentation pile, and controlling the temperature in the pile within the range of 25-35 °C for secondary fermentation, and the fermentation duration is 7-10 days; (e) after the secondary fermentation is completed, drying the material to reduce its water content to less than 15%, and then removing the incompletely decomposed impurities through a screening device to obtain a full-nutrient organic fertilizer with uniform particles.

[0076] In an embodiment of the present application, the addition amounts of lotus leaf powder, weathered coal powder and oyster powder in step (b) are 8%, 15% and 10% of the total mass of the mixture, respectively.

[0077] In an embodiment of the present application, the addition amounts of lipase, microbial inoculum and carbon nanotubes in step (b) are 0.3%, 1.2% and 0.05% of the total mass of the mixture, respectively.

[0078] In an embodiment of the present application, the lipase is Bacillus thermophilus, and the microbial inoculum includes Bacillus subtilis, Lactobacillus and Saccharomyces cerevisiae.

[0079] In an embodiment of the present application, before adding lipase, it includes: performing directed modification on Bacillus thermophilus, wherein a nanozinc oxide-amino acid fragment is introduced at positions 150-160 of the amino acid sequence of Bacillus thermophilus.

[0080] In the embodiment of the present application, in step (c), a temperature sensor is used to monitor the temperature inside the fermentation pile. The temperature sensors are evenly distributed in the upper, middle, and lower layers of the fermentation pile, and at least two sensors are set in each layer.

[0081] In the embodiment of the present application, in step (d), limestone is added during the fermentation process to adjust the pH value.

[0082] In the embodiment of the present application, in step (a), the dehydrated vitamin B12 bacterial residue adopts a vacuum low-temperature dehydration technology, the dehydration temperature is controlled at 40-50°C, and the vacuum degree is -0.06--0.08 MPa.

[0083] In the embodiment of the present application, in step (e), the dried material is subjected to secondary granulation, and a binder accounting for 0.7% of the total mass of the material is added during the granulation process.

[0084] In the embodiment of the present application, the binder is composed of lignocellulose, chitosan and sodium alginate mixed in a mass ratio of 2:1:0.5.

[0085] Example 4 The present invention provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, comprising the following steps: (a) mixing the dehydrated vitamin B12 bacterial residue and the crushed domestic waste in a mass ratio of 4.5:3.5 until uniform; (b) sequentially adding lotus leaf powder, weathered coal powder, oyster powder, and adding lipase, microbial inoculum and carbon nanotubes to the obtained mixture, and stirring and reacting for 2-4 hours under the condition of a temperature range of 30-40°C by a high-speed stirring device. After ensuring that all components are fully and evenly mixed, a fermentation pile is formed by stacking; (c) in the initial stage of fermentation, keep the temperature inside the fermentation pile at 30-40°C for 3-5 days, monitor the temperature during this period, when the temperature rises to 50-60°C, perform the first turning operation, and then continue to ferment for 3-5 days, maintaining the temperature inside the pile at 50-60°C during this period; (d) after the first fermentation is completed, break up the fermentation material and adjust its water content to 50%-60%, stack it again to form a fermentation pile, and control the temperature inside the pile within the range of 25-35°C for secondary fermentation, and the fermentation duration is 7-10 days; (e) after the secondary fermentation is completed, dry the material to make its water content drop below 15%, and then remove the incompletely decomposed impurities through a screening device to obtain a full-nutrient organic fertilizer with uniform particles.

[0086] In the embodiment of the present application, the addition amounts of lotus leaf powder, weathered coal powder, and oyster powder in step (b) are 9%, 18%, and 13% of the total mass of the mixture, respectively.

[0087] In the embodiment of the present application, the addition amounts of lipase, microbial inoculum and carbon nanotubes in step (b) are 0.4%, 1.7%, and 0.08% of the total mass of the mixture, respectively.

[0088] In the embodiment of the present application, the lipase is Bacillus stearothermophilus, and the microbial inoculum includes Bacillus subtilis, lactic acid bacteria and yeast.

[0089] In the embodiment of the present application, before adding the lipase, it includes: performing directed modification on Bacillus stearothermophilus, wherein a nano-zinc oxide-amino acid fragment is introduced at positions 150-160 of the amino acid sequence of Bacillus stearothermophilus.

[0090] In the embodiment of the present application, in step (c), a temperature sensor is used to monitor the temperature inside the fermentation pile. The temperature sensors are evenly distributed in the upper, middle and lower layers of the fermentation pile, and at least two sensors are arranged in each layer.

[0091] In the embodiment of the present application, in step (d), limestone is added during the fermentation process to adjust the pH value.

[0092] In the embodiment of the present application, in step (a), the dehydrated vitamin B12 bacterial residue adopts a vacuum low-temperature dehydration technique, the dehydration temperature is controlled at 40-50 °C, and the vacuum degree is -0.06--0.08 MPa.

[0093] In the embodiment of the present application, in step (e), the dried material is granulated for the second time, and a binder accounting for 0.9% of the total mass of the material is added during the granulation process.

[0094] In the embodiment of the present application, the binder is a mixture of lignocellulose, chitosan and sodium alginate in a mass ratio of 2:1:0.5.

[0095] Example 5 The present invention provides a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, comprising the following steps: (a) Mix the dehydrated vitamin B12 bacterial residue and the crushed domestic waste in a mass ratio of 5:4 until uniform; (b) Add lotus leaf powder, weathered coal powder, oyster powder, and add lipase, microbial inoculum, and carbon nanotubes to the obtained mixture, and stir and react for 2-4 hours under the condition that the temperature range is 30-40 °C by a high-speed stirring device. After ensuring that all components are fully and uniformly mixed, stack them to form a fermentation pile; (c) In the initial stage of fermentation, keep the temperature in the fermentation pile at 30-40 °C for 3-5 days, monitor the temperature during this period, and when the temperature rises to 50-60 °C, perform the first turning operation, and then continue to ferment for 3-5 days, maintaining the temperature in the pile at 50-60 °C during this period; (d) After the first fermentation is completed, break up the fermented materials and adjust their water content to 50%-60%, stack them again to form a fermentation pile, and control the temperature in the pile within the range of 25-35 °C for secondary fermentation, and the fermentation duration is 7-10 days; (e) After the secondary fermentation is completed, dry the materials to reduce their water content to less than 15%, and then remove the incompletely decomposed impurities through a screening device to obtain a full-nutrient organic fertilizer with uniform particles.

[0096] In the embodiment of the present application, the addition amounts of lotus leaf powder, weathered coal powder, and oyster powder in step (b) are 10%, 20%, and 15% of the total mass of the mixture, respectively.

[0097] In the embodiment of the present application, the addition amounts of lipase, microbial inoculum, and carbon nanotubes in step (b) are 0.5%, 2%, and 0.1% of the total mass of the mixture, respectively.

[0098] In the embodiment of the present application, the lipase is Bacillus thermophilus, and the microbial inoculum includes Bacillus subtilis, lactic acid bacteria, and yeast.

[0099] In the embodiment of the present application, before adding lipase, it includes: performing directed modification on Bacillus thermophilus, wherein a nano-zinc oxide-amino acid fragment is introduced at positions 150-160 of the amino acid sequence of Bacillus thermophilus.

[0100] In the embodiment of the present application, in step (c), a temperature sensor is used to monitor the temperature in the fermentation pile, and the temperature sensors are evenly distributed in the upper, middle, and lower layers of the fermentation pile, with at least two sensors provided in each layer.

[0101] In the embodiment of the present application, in step (d), limestone is added during the fermentation process to adjust the PH value.

[0102] In the embodiment of the present application, in step (a), the dehydrated vitamin B12 bacterial residue adopts vacuum low-temperature dehydration technology, the dehydration temperature is controlled at 40-50 °C, and the vacuum degree is -0.06--0.08 MPa.

[0103] In the embodiment of the present application, in step (e), the dried material is subjected to secondary granulation, and a binder accounting for 1% of the total mass of the material is added during the granulation process.

[0104] In the embodiment of the present application, the binder is a mixture of lignocellulose, chitosan and sodium alginate in a mass ratio of 2:1:0.5.

[0105] Comparative Example 1 A method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, which is different from Example 1 only in that lipase is not added, and the rest of the preparation process is the same as that of Example 1.

[0106] Comparative Example 2 A method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, which is different from Example 1 only in that no binder is added during the granulation process, and the rest of the preparation process is the same as that of Example 1.

[0107] Comparative Example 3 A method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue, which is different from Example 1 only in that lipase is not added and no binder is added during the granulation process, and the rest of the preparation process is the same as that of Example 1.

[0108] Performance Test The organic fertilizers prepared in Examples 1-5 and Comparative Examples 1-3 were measured respectively, and the results are shown in Table 1 below.

[0109] Table 1 Test Results Organic matter content (%) Fertilizer utilization rate (%) <![CDATA[Beneficial microorganism quantity (×10 8 CFU / g)]]> Particle strength (N) Anti-breakage rate (%) Example 1 45 38 3.5 5.5 92 Example 2 50 40 4.0 6.0 94 Example 3 56 45 4.5 6.5 96 Example 4 60 52 5.0 7.0 97 Example 5 58 50 4.8 6.9 96 Comparative Example 1 30 30 2.5 5.0 85 Comparative Example 2 40 34 3.0 4.5 75 Comparative Example 3 25 28 2.0 4.0 70 Table 1 test results show that the organic matter content of Examples 1-4 increased gradually, from 45% to 60%, indicating that with the optimization of the raw material ratio, richer organic substrates were provided for fermentation, promoting the accumulation of organic matter. The organic matter content of Example 5 was 58%, slightly lower than that of Example 4, but still remained at a relatively high level overall. This may be due to the complex interactions of various raw materials during fermentation, resulting in the non-continuous increase in the amount of organic matter generated; the organic matter content of Comparative Examples 1-3 was significantly lower than that of the examples, being 30%, 40% and 25% respectively. This shows that there are deficiencies in the raw material composition or fermentation process of the comparative examples, and the conversion and accumulation of organic substances cannot be effectively promoted.

[0110] The fertilizer utilization rate of the examples shows an upward trend, increasing from 38% in Example 1 to 52% in Example 4. This is due to the synergistic effect of various factors. For example, the directionally modified thermophilic Bacillus lipase enhances lipid decomposition, provides more nutrients for microorganisms, and promotes the transformation of nutrients in fertilizers; lotus leaf powder regulates the soil microbial community, weathered coal powder adsorbs and preserves nutrients, and carbon nanotubes accelerate microbial metabolism, etc., jointly improving the efficiency of fertilizer nutrients being absorbed by plants. The fertilizer utilization rate of Example 5 is 50%, showing a slight decrease. Possibly, in actual application, a slight change in the balance of various factors has led to the failure of the utilization rate to continue to increase. The fertilizer utilization rates of the comparative examples are significantly lower than those of the examples, being 30%, 34%, and 28% for Comparative Examples 1 - 3 respectively. Among them, no lipase was added in Comparative Example 1, which affected the acquisition and transformation of nutrients by microorganisms, thus reducing the fertilizer utilization rate.

[0111] The number of beneficial microorganisms in the examples increased steadily from 3.5×10 8 CFU / g in Example 1 to 5.0×10 8 CFU / g in Example 4, which reflects that the entire preparation process created a suitable growth environment for beneficial microorganisms. The directional modification of thermophilic Bacillus endows it with antibacterial properties, inhibits the growth of harmful microorganisms, and provides a competitive advantage for beneficial microorganisms; at the same time, the synergistic effect between various raw materials and microbial inoculants provides rich nutrients and a suitable metabolic environment for beneficial microorganisms, promoting their rapid reproduction. The number of beneficial microorganisms in Example 5 is 4.8×10 8 CFU / g, showing a slight decline. Possibly, during the large-scale fermentation process, the slight fluctuations in environmental factors had a certain impact on the reproduction of microorganisms; the number of beneficial microorganisms in the comparative examples is relatively small, being 2.5×10 8 CFU / g, 3.0×10 8 CFU / g, and 2.0×10 8 CFU / g for Comparative Examples 1 - 3 respectively. This indicates that there are defects in the regulation of microbial growth in the comparative examples, perhaps unable to effectively inhibit harmful microorganisms, or unable to provide sufficient nutrients and good growth conditions for beneficial microorganisms.

[0112] The particle strength of the examples gradually increased from 5.5 N in Example 1 to 7.0 N in Example 4, and the anti-breakage rate also increased from 92% to 97%. The particle strength of Example 5 was 6.9 N and the anti-breakage rate was 96%. This is due to the reasonable use of the binder during the secondary granulation process. The lignocellulose, chitosan, and sodium alginate were mixed in a specific ratio, enhancing the cohesion and stability between the fertilizer particles, enabling the particles to withstand greater external forces and reducing the possibility of breakage. The particle strength and anti-breakage rate of the comparative examples were significantly lower than those of the examples. The particle strengths of Comparative Examples 1-3 were 5.0 N, 4.5 N, and 4.0 N respectively, and the anti-breakage rates were 85%, 75%, and 70% respectively. This indicates that during the granulation process of the comparative examples, there may be insufficient binder dosage, improper proportioning, or imperfect granulation process, resulting in a less compact structure of the fertilizer particles and poor strength and anti-breakage performance.

[0113] In summary, with the reasonable addition of various auxiliary materials such as vitamin B12 bacterial residue, domestic waste, and lotus leaf powder, the organic matter content of the examples gradually increased, and the fertilizer utilization rate and the number of beneficial microorganisms also showed an increasing trend. At the same time, through the reasonable use of the binder, the particle strength and anti-breakage rate of the examples were significantly improved. In contrast, the comparative examples had deficiencies in aspects such as raw material composition, fermentation process, microbial growth regulation, and granulation process, resulting in lower levels than the examples in terms of organic matter content, fertilizer utilization rate, number of beneficial microorganisms, particle strength, and anti-breakage rate.

[0114] According to the present application, a method for preparing a full-nutrient organic fertilizer from vitamin B12 bacterial residue is proposed. By genetically engineering thermophilic Bacillus to introduce a nano-zinc oxide-amino acid fragment to enhance lipase activity and confer antibacterial properties, the vitamin B12 bacterial residue is combined with domestic waste to achieve the resource utilization of waste. At the same time, functional auxiliary materials such as lotus leaf powder, weathered coal powder, and oyster powder are added to regulate the soil microbial community, improve the fertilizer nutrient utilization rate, and provide mineral nutrition. In addition, the adsorption and electron conduction properties of carbon nanotubes are used to promote the growth and fermentation efficiency of microorganisms. The strength and stability of the fertilizer particles are improved through the secondary granulation process and the use of the binder. Finally, the vacuum low-temperature dehydration technology is adopted to effectively retain the bioactive components in the bacterial residue, optimize the dehydration efficiency, reduce the energy consumption cost, and successfully convert the vitamin B12 bacterial residue and domestic waste into a highly efficient, stable, and environmentally friendly full-nutrient organic fertilizer. Thus, the problems of low nutrient content, low utilization rate, and uneven quality in the related art are solved.

[0115] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue, characterized in that: Includes the following: (a) mixing the dehydrated vitamin B12 bacterial residue and the crushed domestic waste in a mass ratio of (3-5):(2-4) until they are uniform; (b) adding lotus leaf powder, weathered coal powder, oyster powder, lipase, microbial agent and carbon nanotubes to the obtained mixture in sequence, stirring the mixture for 2-4 hours at a temperature range of 30-40° C. by a high-speed stirring device to ensure that all components are fully and evenly mixed, and then stacking the mixture to form a fermentation pile; (c) In the initial stage of fermentation, the temperature in the fermentation pile is maintained at 30-40°C for 3-5 days, during which the temperature is monitored. When the temperature rises to 50-60°C, the first compost turning operation is performed, and then the fermentation is continued for 3-5 days, during which the temperature in the compost is maintained at 50-60°C; (d) After the first fermentation is completed, the fermented materials are dispersed and the water content is adjusted to 50%-60%, and then piled up again to form a fermentation pile. The temperature in the pile is controlled within the range of 25-35° C. for secondary fermentation. The fermentation duration is 7-10 days; (e) After the secondary fermentation, the material is dried to reduce its moisture content to below 15%, and then the impurities that are not completely decomposed are removed through screening equipment to obtain a complete nutrient organic fertilizer with uniform particles.

2. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 1, wherein: In step (b), the addition amounts of the lotus leaf powder, the weathered coal powder and the oyster powder are 5%-10%, 10%-20% and 5%-15% of the total mass of the mixture respectively.

3. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 1, characterized in that: In step (b), the added amounts of the lipase, the microbial agent and the carbon nanotubes are 0.1%-0.5%, 0.5%-2% and 0.01%-0.1% of the total mass of the mixture, respectively.

4. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 3, characterized in that: The lipase is thermophilic bacillus, and the microbial agent includes bacillus subtilis, lactic acid bacteria and yeast.

5. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 1 or 4, characterized in that: Before adding lipase, include: The thermophilic Bacillus is subjected to a directed transformation, wherein a nano zinc oxide-amino acid fragment is introduced into the thermophilic Bacillus at positions 150-160 of the amino acid sequence.

6. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 1, characterized in that: In step (c), temperature sensors are used to monitor the temperature in the fermentation pile. The temperature sensors are evenly distributed in the upper, middle and lower layers of the fermentation pile, and at least two sensors are arranged in each layer.

7. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 1, characterized in that: In step (d), limestone is added during the fermentation process to adjust the pH value.

8. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 1, characterized in that: In step (a), the dehydrated vitamin B12 residue is subjected to vacuum low-temperature dehydration technology, the dehydration temperature is controlled at 40-50° C., and the vacuum degree is -0.06--0.08 MPa.

9. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 1, characterized in that: In step (e), the dried material is subjected to secondary granulation, and a binder accounting for 0.5% to 1% of the total mass of the material is added during the granulation process.

10. The method for preparing a complete nutrient organic fertilizer from vitamin B12 fungus residue according to claim 9, characterized in that: The binder is a mixture of wood-based cellulose, chitosan and sodium alginate in a mass ratio of 2:1:0.5.

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