Method for preparing biological fertilizer by using valine fermentation liquor

Abstract

The invention discloses a preparation method for preparing a biological fertilizer by using valine fermentation liquor, and relates to the technical field of biological fertilizer preparation, and the preparation method has the advantages that large-particle impurities and suspended solids are effectively removed by pretreating the valine fermentation liquor and using a ceramic microfiltration membrane, so that a foundation is laid for subsequent purification; then, a special adsorption material is adopted, mesoporous silica is used as a basis, after amino functional groups are introduced through surface modification, the chemical property of the adsorption material is changed, the affinity to valine is enhanced, a polymerization reaction is performed under the action of an initiator to form a polymer network, then the template molecule valine is removed, and the adsorption material is prepared. According to the present invention, the high-purity valine solution is added to the valine solution, such that the identification site complementary to the shape, the size and the chemical function of the valine is left, the valine can be accurately identified and adsorbed, the separation purification effect of the valine is substantially improved, and the accuracy and the stability of the fertilizer nutritional components can be effectively ensured when the obtained high-purity valine solution is mixed with other nutrients.

Description

Technical Field

[0001] The invention relates to the technical field of biofertilizer preparation, in particular to a method for preparing biofertilizer by utilizing valine fermentation liquid. Background Art

[0002] As an environmentally friendly fertilizer, biofertilizer has received more and more attention. Biofertilizer refers to fertilizer containing a large number of beneficial microorganisms and organic matter. It can improve soil structure, increase soil fertility, improve the activity of microorganisms in the soil, promote plant absorption and utilization of nutrients, enhance plant resistance, and reduce the occurrence of diseases and insect pests. Compared with traditional chemical fertilizers, biofertilizer has the advantages of sustainability, environmental protection, and friendliness to soil ecosystems. Therefore, the development of efficient and high-quality biofertilizers has become an important direction of current agricultural fertilizer research. Valine fermentation broth is a by-product produced in the industrial production of valine. Valine is an essential amino acid for the human body and is widely used in the pharmaceutical, food, feed and other industries. In the fermentation production process of valine, a large amount of fermentation broth is produced, which contains not only valine but also other amino acids, sugars, inorganic salts, vitamins and microorganisms. These ingredients make the valine fermentation broth have certain nutritional value and potential application value; There are certain technical problems in the existing technology. First, the traditional method is not good for purifying valine fermentation broth, and there are many impurities, which affects the accuracy of fertilizer components. Secondly, the waste liquid treatment is simple in the past, and resources are not fully utilized, and it is impossible to make high-quality compound fertilizers, resulting in low utilization rate of fermentation broth. Moreover, the common nutrient mixing process is rough, it is difficult to accurately control the proportion, and it is easy to have uneven nutrition. It is impossible to fully consider the special needs of different crops for nutrients at different growth stages, and it is difficult to achieve ideal fertilization effects, affecting crop yield and quality. To this end, we propose a preparation method for preparing bio-fertilizer using valine fermentation broth. Summary of the invention

[0003] The object of the present invention is to provide a method for preparing bio-fertilizer by utilizing valine fermentation liquid.

[0004] In order to solve the problems raised in the above background technology, the present invention provides the following technical solution: a method for preparing bio-fertilizer by using valine fermentation liquid, the method for preparing bio-fertilizer specifically comprises the following steps: Step 1: pretreatment of the fermentation broth. First, the valine fermentation broth is preliminarily tested to determine its main components and contents. The fermentation broth is placed in a reaction vessel and filtered using a ceramic microfiltration membrane. The fermentation broth is passed through the microfiltration membrane at a stable flow rate to remove larger particle impurities and suspended solids in the fermentation broth. At the same time, the filtered fermentation broth is collected. Step 2, separation and purification of valine, using an adsorption material to separate and purify valine from the pretreated fermentation broth, the adsorption material is based on mesoporous silica, the mesoporous silica is first surface-modified, and the interaction with valine is enhanced by introducing amino functional groups, and then the molecular imprinting technology is used to construct a valine-specific recognition site. During the adsorption process, the pretreated fermentation broth is mixed with the adsorption material and placed in a container with a stirring device for adsorption. After the adsorption is completed, the adsorption material is separated from the fermentation broth by centrifugation; Step 3: desorption treatment, desorption treatment is performed on the adsorbed material, the adsorbed material is immersed in a desorbent, and then placed together in a desorption container for desorption, and stirred during the desorption process to improve the desorption efficiency. After the desorption is completed, the desorbent is separated from the high-purity valine solution by centrifugation to obtain a high-purity valine solution; Step 4, mixing nutrients, mixing the high-purity valine solution with other nutrients in proportion, first, determining the addition ratio of each nutrient, the added nutrients include humic acid, trace elements and growth regulators, the growth regulator is gibberellin, adding each nutrient to the high-purity valine solution in turn, placing it in a stirring container for stirring, so that each nutrient is fully mixed, after mixing, the mixed solution is allowed to settle, and a small amount of precipitate that may exist is removed to obtain a clarified liquid fertilizer mixture; Step 5, waste liquid treatment and fertilizer preparation, collect the waste liquid generated in the preparation process, first remove large particles of impurities through preliminary filtration, then introduce the waste liquid into an evaporation concentration device for evaporation concentration, evaporate the water in the waste liquid, until the salt and other impurities in the waste liquid are concentrated into a paste, take out the paste, mix it with organic materials, the organic materials include straw powder and livestock and poultry manure, then add microbial agents, put the mixture into a fermentation tank for composting fermentation, turn the pile regularly during the fermentation process to ensure uniform fermentation, and make compound fertilizer after fermentation.

[0005] As a further scheme of the present invention: in the step 1, the fermentation liquid is placed in a reaction container, the temperature of the fermentation liquid is controlled to be 30°C-35°C, and a ceramic microfiltration membrane with a pore size of 0.2μm-0.5μm is used for filtration operation. During the filtration process, the filtration pressure is controlled to be 0.2MPa-0.3MPa.

[0006] As a further scheme of the present invention: in the step 2, the functional monomer used in the molecular imprinting technology in the adsorption material is methacrylic acid, and the specific operation of constructing the valine-specific recognition site using the molecular imprinting technology is as follows: first, valine and methacrylic acid functional monomers are mixed in a molar ratio of 1:3-4, an initiator azobisisobutyronitrile is added, and a polymerization reaction is carried out at a temperature of 50°C-60°C for 8h-10h to form a polymer network, and then, the polymer network is soaked in a sodium hydroxide solution with a concentration of 0.1mol / L-0.2mol / L to remove the template molecule valine, leaving a recognition site that is complementary to the shape, size and chemical function of valine.

[0007] As a further solution of the present invention: In the step 2, during the adsorption process, the adsorption is carried out at a temperature of 25°C-30°C and a pH value of 6.5-7.5, the stirring speed is controlled to be 50r / min-80r / min, and the adsorption time is 2h-3h.

[0008] As a further solution of the present invention: in the step three, the desorbent uses a hydrochloric acid solution with a concentration of 0.5 mol / L-1 mol / L, the temperature of the desorption container is controlled at 40°C-45°C, the desorption time is 1.5h-2h, and the stirring speed is 30r / min-50r / min.

[0009] As a further scheme of the present invention: in the step 4, valine accounts for 20%-30% of the total mass, humic acid accounts for 30%-40% of the total mass, the trace elements are sulfates of iron, zinc, copper and manganese, each accounting for 0.5%-1% of the total mass, and the growth regulator gibberellin accounts for 0.1%-0.5% of the total mass.

[0010] As a further solution of the present invention: in the step 4, the temperature of the stirring container is controlled at 20°C-25°C, and the stirring speed is 30r / min-50r / min for 1h-2h. After mixing evenly, the mixed solution is allowed to stand and settle for 2h-3h.

[0011] As a further solution of the present invention: in the step 5, the temperature of the evaporation concentration device is controlled at 60°C-80°C, the mixing ratio of the paste substance to the organic material is 1:3-5 by mass ratio, the microbial agent is a composite agent composed of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium, and Bacillus gelatinus, and the addition amount of the microbial agent is 0.5%-1% of the total mass of the paste substance and the organic material.

[0012] As a further solution of the present invention: in the step 5, the temperature in the fermentation tank is controlled at 30°C-35°C, and the humidity is 60%-70%. During the fermentation process, the compost is turned over every 2-3 days, and the fermentation time is 15-20 days.

[0013] By adopting the above technical solution, compared with the prior art, the beneficial effects of the present invention are: 1. The present invention pre-treats the valine fermentation broth, and the use of a ceramic microfiltration membrane effectively removes larger particle impurities and suspended solids, laying a foundation for subsequent purification. Then, a special adsorption material is used, which is based on mesoporous silica. After surface modification and introduction of amino functional groups, its chemical properties are changed, and its affinity for valine is enhanced. The molecular imprinting technology further improves its specificity. Valine and methacrylic acid functional monomers are mixed in a specific ratio, and a polymerization reaction is carried out under the action of an initiator to form a polymer network. Then, the template molecule valine is removed, and a recognition site complementary to the shape, size and chemical function of valine is left. Valine can be accurately identified and adsorbed, which greatly improves the separation and purification effect of valine. The obtained high-purity valine solution can more effectively ensure the accuracy and stability of fertilizer nutrients when mixed with other nutrients. 2. The present invention collects waste liquid and initially filters to remove large particles of impurities, then reduces the water content in the waste liquid by evaporation and concentration, and concentrates salt and other impurities into a paste-like substance. The paste-like substance is mixed with organic materials, and then a microbial agent composed of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium and Bacillus gelatinus is added. These microorganisms can efficiently decompose nutrients in organic materials and paste-like substances in the fermentation tank and convert them into a form that is more easily absorbed by plants. The final composite fertilizer not only contains rich nutrients, but also improves soil structure and soil fertility, thereby achieving effective conversion of waste liquid and maximizing resource utilization; 3. The present invention mixes humic acid, trace elements (sulfates of iron, zinc, copper, and manganese) and growth regulators (gibberellic acid) in a specific ratio. Humic acid can improve soil structure, increase soil fertility, and increase soil water and fertilizer retention capacity. Trace elements are essential nutrients for crop growth and participate in various physiological metabolic processes of crops. Gibberellic acid, as a growth regulator, can regulate the growth and development of crops and promote cell elongation and division. These nutrients are fully and evenly mixed under suitable temperature and stirring conditions to avoid local excess or deficiency of nutrients. After mixing, the liquid fertilizer is allowed to settle to remove a small amount of sediment that may exist, thereby further optimizing the quality of the liquid fertilizer. This optimized nutrient mixing process enables the fertilizer to better meet the needs of crops at different growth stages and improve the yield and quality of crops. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of the method steps in an embodiment of the present invention; Figure 2 Schematic diagram of performance comparison of embodiments of the present invention. DETAILED DESCRIPTION

[0015] The specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0016] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0017] Please refer to the attached Figure 1 -Attached Figure 2 The present invention provides a method for preparing bio-fertilizer by using valine fermentation liquid, and the method for preparing bio-fertilizer specifically comprises the following steps: Step 1: pretreatment of the fermentation broth. First, the valine fermentation broth is preliminarily tested to determine its main components and contents. The fermentation broth is placed in a reaction vessel and filtered using a ceramic microfiltration membrane. The fermentation broth is passed through the microfiltration membrane at a stable flow rate to remove larger particle impurities and suspended solids in the fermentation broth. At the same time, the filtered fermentation broth is collected. Step 2, separation and purification of valine, using an adsorption material to separate and purify valine from the pretreated fermentation broth, the adsorption material is based on mesoporous silica, the mesoporous silica is first surface-modified, and the interaction with valine is enhanced by introducing amino functional groups, and then the molecular imprinting technology is used to construct a valine-specific recognition site. During the adsorption process, the pretreated fermentation broth is mixed with the adsorption material and placed in a container with a stirring device for adsorption. After the adsorption is completed, the adsorption material is separated from the fermentation broth by centrifugation; Step 3: desorption treatment, desorption treatment is performed on the adsorbed material, the adsorbed material is immersed in a desorbent, and then placed together in a desorption container for desorption, and stirred during the desorption process to improve the desorption efficiency. After the desorption is completed, the desorbent is separated from the high-purity valine solution by centrifugation to obtain a high-purity valine solution; Step 4, mixing nutrients, mixing the high-purity valine solution with other nutrients in proportion, first, determining the addition ratio of each nutrient, the added nutrients include humic acid, trace elements and growth regulators, the growth regulator is gibberellin, adding each nutrient to the high-purity valine solution in turn, placing it in a stirring container for stirring, so that each nutrient is fully mixed, after mixing, the mixed solution is allowed to settle, and a small amount of precipitate that may exist is removed to obtain a clarified liquid fertilizer mixture; Step 5, waste liquid treatment and fertilizer preparation, collect the waste liquid generated in the preparation process, first remove large particles of impurities through preliminary filtration, then introduce the waste liquid into an evaporation concentration device for evaporation concentration, evaporate the water in the waste liquid, until the salt and other impurities in the waste liquid are concentrated into a paste, take out the paste, mix it with organic materials, the organic materials include straw powder and livestock and poultry manure, then add microbial agents, put the mixture into a fermentation tank for composting fermentation, turn the pile regularly during the fermentation process to ensure uniform fermentation, and make compound fertilizer after fermentation.

[0018] In one embodiment of the present invention: in step 1, the fermentation liquid is placed in a reaction container, the temperature of the fermentation liquid is controlled to be 30°C-35°C, and a ceramic microfiltration membrane with a pore size of 0.2μm-0.5μm is used for filtration operation. During the filtration process, the filtration pressure is controlled to be 0.2MPa-0.3MPa.

[0019] In one embodiment of the present invention: in step 2, the functional monomer used in the molecular imprinting technology in the adsorption material is methacrylic acid, and the specific operation of constructing the valine-specific recognition site using the molecular imprinting technology is as follows: first, valine and methacrylic acid functional monomers are mixed in a molar ratio of 1:3-4, and an initiator azobisisobutyronitrile is added, and a polymerization reaction is carried out at a temperature of 50°C-60°C for 8h-10h to form a polymer network. Then, the polymer network is soaked in a sodium hydroxide solution with a concentration of 0.1mol / L-0.2mol / L to remove the template molecule valine, leaving a recognition site that is complementary to the shape, size and chemical function of valine.

[0020] In one embodiment of the present invention: In step 2, during the adsorption process, the adsorption is carried out at a temperature of 25°C-30°C and a pH value of 6.5-7.5, the stirring speed is controlled to be 50r / min-80r / min, and the adsorption time is 2h-3h.

[0021] In one embodiment of the present invention: in step three, the desorbent uses a hydrochloric acid solution with a concentration of 0.5 mol / L-1 mol / L, the temperature of the desorption container is controlled at 40°C-45°C, the desorption time is 1.5h-2h, and the stirring speed is 30r / min-50r / min.

[0022] In one embodiment of the present invention: in step 4, valine accounts for 20%-30% of the total mass, humic acid accounts for 30%-40% of the total mass, trace elements are sulfates of iron, zinc, copper, and manganese, each accounting for 0.5%-1% of the total mass, and the growth regulator gibberellin accounts for 0.1%-0.5% of the total mass.

[0023] In one embodiment of the present invention: in step 4, the temperature of the stirring container is controlled at 20°C-25°C, and the stirring speed is 30r / min-50r / min for 1h-2h. After mixing evenly, the mixed solution is allowed to stand and settle for 2h-3h.

[0024] In one embodiment of the present invention: in step five, the temperature of the evaporation concentration device is controlled at 60°C-80°C, the mixing ratio of the paste substance to the organic material is 1:3-5 by mass ratio, the microbial agent is a composite agent composed of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium, and Bacillus gelatinus, and the addition amount of the microbial agent is 0.5%-1% of the total mass of the paste substance and the organic material.

[0025] In one embodiment of the present invention: in step five, the temperature in the fermentation tank is controlled at 30°C-35°C, and the humidity is 60%-70%. During the fermentation process, the compost is turned every 2-3 days, and the fermentation time is 15-20 days.

[0026] Example 1, please refer to the attached Figure 1 -Attached Figure 2First, the valine fermentation broth was preliminarily tested to determine the composition and content, and then placed in a reaction vessel and filtered at 35°C using a ceramic microfiltration membrane with a pore size of 0.5 μm and a filtration pressure of 0.3 MPa to remove larger particle impurities and solid suspended matter and collect the filtered fermentation broth. Then, mesoporous silica was used as the substrate, and amino functional groups were introduced through surface modification and molecular imprinting technology was used (valine and methacrylic acid functional monomers were mixed in a ratio of 1:3, azobisisobutyronitrile was added and polymerized at 60°C for 10 hours, and then soaked in 0.2 mol / L sodium hydroxide solution to remove valine and leave the recognition site) to construct an adsorption material with specific recognition sites. Under the conditions of 25°C and pH 7.5, the adsorption was carried out at a stirring speed of 80 r / min for 3 hours. After adsorption, the adsorption material and the fermentation broth were separated by centrifugation, and then the adsorption material was immersed in a hydrochloric acid solution with a concentration of 1 mol / L and stirred at 50 r / min at 45°C. The mixture was desorbed at a stirring speed of 2 h, and after desorption, a high-purity valine solution was obtained by centrifugation. The high-purity valine solution was then mixed with other nutrients, which accounted for 30% of valine, 40% of humic acid, 1% of trace elements (iron, zinc, copper, manganese sulfate, each accounting for 1%), and 0.5% of gibberellin in a mass ratio. The mixture was stirred at 50 r / min for 2 h at 25 ° C. After being evenly mixed, it was allowed to settle for 3 h to remove a small amount of precipitate to obtain a clarified liquid fertilizer mixture. Finally, the waste liquid generated in the preparation process was collected, and the large particles of impurities were initially filtered to remove them. The mixture was then introduced into an evaporation concentration device at 80 ° C for evaporation and concentration to concentrate the salt and impurities into a paste-like substance. The waste liquid was mixed with straw powder and livestock and poultry manure in a mass ratio of 1:5, and a microbial agent consisting of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium, and Bacillus gelatinus accounting for 1% of the total mass of the paste-like substance and organic materials was added. The mixture was placed in a fermentation tank at 35 ° C and a humidity of 70%, and the pile was turned over every 3 days for 18 days to obtain a compound fertilizer.

[0027] Example 2, please refer to the attached Figure 1 -Attached Figure 2First, the valine fermentation broth was preliminarily tested to determine the composition and content, and then placed in a reaction vessel and filtered at 35°C using a ceramic microfiltration membrane with a pore size of 0.5 μm and a filtration pressure of 0.3 MPa to remove larger particle impurities and suspended solids and collect the filtered fermentation broth. Then, the valine in the fermentation broth was adsorbed using an activated carbon adsorption material. At 25°C and a pH value of 7.5, the adsorption was carried out at a stirring speed of 80 r / min for 3 hours. After adsorption, the adsorption material and the fermentation broth were centrifuged and then immersed in a hydrochloric acid solution with a concentration of 1 mol / L, and desorbed at a stirring speed of 50 r / min for 2 hours at 45°C. After desorption, a high-purity valine solution was obtained by centrifugation. The high-purity valine solution was then mixed with a 30% valine solution by mass. The mixture is mixed with 40% humic acid, 40% trace elements (iron, zinc, copper, manganese sulfate each account for 1%), and other nutrients accounting for 0.5% of gibberellins, stirred at 50r / min at 25℃ for 2h, allowed to stand and settle for 3h after mixing evenly, and a small amount of precipitate was removed to obtain a clarified liquid fertilizer mixture; finally, the waste liquid generated in the preparation process was collected, first preliminarily filtered to remove large particles of impurities, and then introduced into an evaporation concentration device at 80℃ for evaporation and concentration, so that the salt and impurities were concentrated into a paste-like substance, which was mixed with straw powder and livestock and poultry manure at a mass ratio of 1:5, and microbial inoculants composed of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium and Bacillus gelatinus accounting for 1% of the total mass of the paste-like substance and organic materials were added; the mixture was placed in a fermentation tank at 35℃ and 70% humidity, turned over every 3 days, and fermented for 18 days to obtain a compound fertilizer.

[0028] Example 3, please refer to the attached Figure 1 -Attached Figure 2First, the valine fermentation broth was preliminarily tested to determine the composition and content, and then placed in a reaction vessel and filtered at 35°C using a ceramic microfiltration membrane with a pore size of 0.5 μm and a filtration pressure of 0.3 MPa to remove larger particle impurities and suspended solids and collect the filtered fermentation broth. Then, an adsorption material with a silica gel as the substrate and amino functional groups introduced by surface modification was used. At 25°C and a pH value of 7.5, the adsorption was carried out at a stirring speed of 80 r / min for 3 hours. After adsorption, the adsorption material and the fermentation broth were separated by centrifugation. Then, the adsorption material was immersed in a hydrochloric acid solution with a concentration of 1 mol / L, and desorbed at a stirring speed of 50 r / min for 2 hours at 45°C. After desorption, a high-purity valine solution was obtained by centrifugation. The high-purity valine solution was then mixed with a 3% valine solution by mass. 0%, humic acid accounting for 40%, trace elements (iron, zinc, copper, manganese sulfate accounting for 1% each), gibberellin accounting for 0.5% of other nutrients are mixed, stirred at 50r / min at 25℃ for 2h, mixed evenly and allowed to settle for 3h to remove a small amount of precipitate to obtain a clarified liquid fertilizer mixture, finally the waste liquid generated in the preparation process is collected, first preliminarily filtered to remove large particles of impurities, and then introduced into an evaporation concentration device at 80℃ for evaporation and concentration, so that the salt and impurities are concentrated into a paste-like substance, which is mixed with straw powder and livestock and poultry manure at a mass ratio of 1:5, and microbial inoculants composed of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium and Bacillus gelatinum accounting for 1% of the total mass of the paste-like substance and organic materials are added, and placed in a fermentation tank at 35℃ and 70% humidity, turned over every 3 days, and fermented for 18 days to obtain a compound fertilizer.

[0029] Design of the experiment: Prepare experimental materials: three equal parts of valine fermentation broth, mesoporous silica-based adsorption material (Example 1), activated carbon adsorption material (Example 2), silica-based adsorption material (Example 3), methacrylic acid, azobisisobutyronitrile, sodium hydroxide solution, hydrochloric acid solution, humic acid, trace elements (iron, zinc, copper, manganese sulfate), gibberellin, straw powder, livestock and poultry manure, Bacillus subtilis and other microbial agents, experimental soil and planted crop seeds, analytical testing instruments, such as high performance liquid chromatograph, pH meter, chemical analysis equipment, microbial counting equipment, etc.; Experimental steps: Experimental preparation stage Three experimental fields of the same area and uniform texture were selected, marked as groups A, B, and C, respectively, corresponding to Example 1, Example 2, and Example 3. Initial tests were performed on the soil of the three experimental fields, including soil pH value, organic matter content, nitrogen, phosphorus, and potassium content, microbial activity, and other indicators, and the results were recorded. Crop seeds of the same variety and good growth conditions were selected, disinfected, and set aside. Biofertilizer preparation stage: prepare according to the process flow of Example 1, Example 2 and Example 3; Fertilization and planting stage: The three prepared biofertilizers were evenly applied to the three experimental fields A, B, and C, and the fertilizer application amount was strictly kept consistent. Crop seeds were sown in the three experimental fields, and the sowing depth and spacing were kept consistent. The experimental fields were uniformly watered to keep the soil moisture within an appropriate range. During the data collection phase, data is collected regularly at different stages of crop growth (germination, growth, maturity, etc.); Fertilizer purity determination: The valine content in the biofertilizer was determined by high performance liquid chromatography and other analytical methods. Fertilizer purity = valine content / total mass of biofertilizer × 100%. Samples were taken from the biofertilizers applied in the three experimental fields of A, B, and C for analysis. Plant nutrient absorption determination: a certain number of plant samples are randomly selected at different growth stages of crops; After harvesting crops, their different parts (such as leaves, stems, fruits, etc.) are crushed separately, and the content of nitrogen, phosphorus, potassium and other elements is determined by chemical analysis methods. The amount of a certain element absorbed by plants = the total content of the element in the crops / total weight of the crops; Fermentation broth utilization rate determination, record the total amount of effective ingredients (such as valine, etc.) in each example from the valine fermentation broth to the final bio-fertilizer preparation process, fermentation broth utilization rate = total amount of effective ingredients in the final bio-fertilizer / total amount of effective ingredients in the initial fermentation broth × 100%; Soil fertility improvement determination, using potassium dichromate volumetric method to determine soil organic matter content, using pH meter to determine soil pH, using plate count method to determine the number of microorganisms in the soil as an indicator of microbial activity; Crop selection, wheat was selected as the experimental crop; Experimental time period, the growth cycle of wheat is about 230 days, the experimental time period is set to 8 months, the specific arrangements are as follows, preparation before sowing (1 month): including preparation of experimental fields, soil testing, preparation of bio-fertilizer, etc., germination period to growth period (3 months): regular observation of wheat growth, including emergence time, plant height, number of leaves, etc., and preliminary determination of indicators such as soil fertility and fertilizer purity, filling period to maturity period (3 months), pay attention to wheat nutrient absorption, soil fertility changes, microbial activity and other indicators, and do a good job of data recording and sample collection, harvest period (1 month): determination of wheat yield and quality, and final detection and analysis of soil, collation of experimental data and conclusions.

[0030] As attached Figure 2As shown, by comparing the biofertilizers prepared in Examples 1, 2 and 3, the results show that the biofertilizer in Example 1 performs better in all aspects, and its fertilizer purity reaches 88.5%, which is significantly higher than 82.3% in Example 2 and 78.6% in Example 3. In terms of plant nutrient absorption, the nitrogen, phosphorus and potassium absorption in Example 1 is also higher, and the fermentation liquid utilization rate is 83.2%, which is higher than that in Example 2 and Example 3. At the same time, Example 1 has outstanding effects in improving soil organic matter content and microbial activity, stabilizing soil pH, etc., which strongly proves the superiority and application potential of the biofertilizer in Example 1.

[0031] Although the present invention is disclosed as above in terms of preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for preparing biofertilizer using valine fermentation liquid, characterized in that: The method for preparing the bio-fertilizer specifically comprises the following steps: Step 1: pretreatment of the fermentation broth. First, the valine fermentation broth is preliminarily tested to determine its main components and contents. The fermentation broth is placed in a reaction vessel and filtered using a ceramic microfiltration membrane to remove larger particle impurities and suspended solids in the fermentation broth. Meanwhile, the filtered fermentation broth is collected. Step 2, separation and purification of valine, using an adsorption material to separate and purify valine from the pretreated fermentation broth, the adsorption material is based on mesoporous silica, the mesoporous silica is first surface-modified, and the interaction with valine is enhanced by introducing amino functional groups, and then the molecular imprinting technology is used to construct a valine-specific recognition site. During the adsorption process, the pretreated fermentation broth is mixed with the adsorption material and placed in a container with a stirring device for adsorption. After the adsorption is completed, the adsorption material is separated from the fermentation broth by centrifugation; Step 3: desorption treatment, desorption treatment is performed on the adsorbed material, the adsorbed material is immersed in a desorbent, and then placed in a desorption container for desorption, stirring is performed during the desorption process, and after the desorption is completed, the desorbent and the high-purity valine solution are separated by centrifugation to obtain a high-purity valine solution; Step 4, mixing nutrients, mixing the high-purity valine solution with other nutrients in proportion, first, determining the addition ratio of each nutrient, the added nutrients include humic acid, trace elements and growth regulators, the growth regulator is gibberellin, adding each nutrient to the high-purity valine solution in turn, placing in a stirring container for stirring, so that each nutrient is fully mixed, after mixing, the mixed solution is statically precipitated to obtain a clarified liquid fertilizer mixture; Step 5, waste liquid treatment and fertilizer preparation, collect the waste liquid generated in the preparation process, first remove large particles of impurities through preliminary filtration, then introduce the waste liquid into an evaporation concentration device for evaporation concentration, evaporate the water in the waste liquid, until the salt and other impurities in the waste liquid are concentrated into a paste, take out the paste, mix it with organic materials, the organic materials include straw powder and livestock and poultry manure, then add microbial agents, put the mixture into a fermentation tank for composting fermentation, turn the pile regularly during the fermentation process, and make compound fertilizer after fermentation.

2. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In the step 1, the fermentation liquid is placed in a reaction container, the temperature of the fermentation liquid is controlled to be 30°C-35°C, and a ceramic microfiltration membrane with a pore size of 0.2μm-0.5μm is used for filtration operation. During the filtration process, the filtration pressure is controlled to be 0.2MPa-0.3MPa.

3. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In the step 2, the functional monomer used in the molecular imprinting technology in the adsorption material is methacrylic acid, and the specific operation of constructing the valine-specific recognition site using the molecular imprinting technology is as follows: first, valine and methacrylic acid functional monomers are mixed in a molar ratio of 1:3-4, an initiator azobisisobutyronitrile is added, and a polymerization reaction is carried out at a temperature of 50° C.-60° C. for 8 h-10 h to form a polymer network, and then, the polymer network is soaked in a sodium hydroxide solution with a concentration of 0.1 mol / L-0.2 mol / L to remove the template molecule valine, leaving a recognition site that is complementary to the shape, size and chemical function of valine.

4. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In the step 2, during the adsorption process, the adsorption is carried out at a temperature of 25° C.-30° C. and a pH value of 6.5-7.5, the stirring speed is controlled to be 50 r / min-80 r / min, and the adsorption time is 2 h-3 h.

5. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In the step 3, the desorbent is a hydrochloric acid solution with a concentration of 0.5 mol / L-1 mol / L, the temperature of the desorption container is controlled at 40°C-45°C, the desorption time is 1.5h-2h, and the stirring speed is 30r / min-50r / min.

6. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In the step 4, valine accounts for 20%-30% of the total mass, humic acid accounts for 30%-40% of the total mass, trace elements are sulfates of iron, zinc, copper and manganese, each accounting for 0.5%-1% of the total mass, and the growth regulator gibberellin accounts for 0.1%-0.5% of the total mass.

7. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In the step 4, the temperature of the stirring container is controlled at 20°C-25°C, and the mixture is stirred at a stirring speed of 30r / min-50r / min for 1h-2h. After mixing evenly, the mixed solution is allowed to settle for 2h-3h.

8. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In the step 5, the temperature of the evaporation concentration device is controlled at 60° C.-80° C., the mixing ratio of the paste substance to the organic material is 1:3-5 by mass ratio, the microbial agent is a composite agent composed of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium, and Bacillus gelatinus, and the addition amount of the microbial agent is 0.5%-1% of the total mass of the paste substance and the organic material.

9. A method for preparing bio-fertilizer by utilizing valine fermentation liquid according to claim 1, characterized in that: In step 5, the temperature in the fermentation tank is controlled at 30° C.-35° C., and the humidity is 60%-70%. During the fermentation process, the compost is turned every 2-3 days, and the fermentation time is 15-20 days.

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