Pretreatment process for preparing liquid fertilizer by utilizing glutamic acid fermentation liquor

Abstract

The invention discloses a pretreatment process for preparing a liquid fertilizer by using glutamic acid fermentation liquor, and relates to the technical field of liquid fertilizer preparation, a bacillus subtilis culture solution is prepared, the culture solution is treated, bacillus subtilis thalli are collected, then a nitrogen mustard chemical mutagenic agent is used for treating bacillus subtilis, and the liquid fertilizer is prepared. The method has the advantages that a large number of adsorption sites are provided for the glutamic acid, the adsorption capacity of the glutamic acid is greatly improved, the adsorption capacity of the glutamic acid is greatly improved, and the utilization rate of the glutamic acid is increased. The concentrated sulfuric acid modified high-molecular polymer into which a sulfonic active group is introduced can be subjected to specific chemical bonding with glutamic acid, so that impurities in the fermentation liquor are effectively removed, the adsorption capacity to glutamic acid is enhanced, the purity of the liquid fertilizer is improved, and the utilization value of the glutamic acid fermentation liquor is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of liquid fertilizer preparation, in particular to a pretreatment process for preparing liquid fertilizer by utilizing glutamic acid fermentation liquid. Background Art

[0002] With the continuous development of agriculture, the demand for efficient and environmentally friendly liquid fertilizers is growing. As a potential resource, glutamic acid fermentation liquid has great utilization value for preparing liquid fertilizers. However, in the process of preparing liquid fertilizers using glutamic acid fermentation liquid, many technical difficulties and challenges are faced. In traditional agricultural production, although the large-scale use of chemical fertilizers has increased the yield of crops to a certain extent, it has also brought a series of environmental problems, such as soil compaction and eutrophication of water bodies. Therefore, the development of new liquid fertilizers has become an important direction for sustainable agricultural development. Liquid fertilizers have the advantages of high nutrient content, easy absorption, and convenient use, and can meet the needs of modern agriculture for efficient fertilization. Glutamic acid fermentation liquid is a by-product produced in the process of glutamic acid production. Glutamic acid, as an important amino acid, is widely used in the fields of food, medicine, and chemical industry. In the process of glutamic acid fermentation, a large amount of fermentation liquid is produced, which contains rich nutrients, such as amino acids, organic acids, trace elements, etc. If these fermentation liquids can be effectively utilized to prepare liquid fertilizers, not only can the recycling of resources be achieved, but also the production cost can be reduced and environmental pollution can be reduced. The existing technology has certain defects. First, there is a lack of materials and methods for efficiently adsorbing glutamate, resulting in limited adsorption capacity and incomplete impurity removal, which reduces the purity and utilization value of liquid fertilizer. Secondly, the current technology is difficult to effectively treat fixed suspended matter, and it is impossible to flocculate the fixed suspended matter and form flocs, which makes it difficult to separate the fixed suspended matter, increases the impact of impurities, and reduces the efficiency of liquid fertilizer preparation. Furthermore, the existing treatment method lacks accuracy and specificity in separating charged suspended matter, resulting in low suspended matter separation efficiency, affecting the preparation of high-quality liquid fertilizer. For this reason, we propose a pretreatment process for preparing liquid fertilizer using glutamate fermentation broth. Summary of the invention

[0003] The purpose of the present invention is to provide a pretreatment process for preparing liquid fertilizer by utilizing glutamic acid fermentation liquid.

[0004] In order to solve the problems raised in the above background technology, the present invention provides the following technical solution: a pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid, the pretreatment process comprising the following specific steps: Step 1, preparing a Bacillus subtilis culture solution, treating the culture solution to collect Bacillus subtilis cells, then treating the Bacillus subtilis with a nitrogen mustard chemical mutagen, then collecting the cells by centrifugation, placing the fermentation solution and the treated Bacillus subtilis in a constant temperature shaking incubator for reaction, so that the fixed suspended matter in the fermentation solution is flocculated; Step 2: prepare a specific adsorption material, react a mineral material with a modified high molecular polymer to form a composite material with a specific spatial configuration and functional groups. The mineral material is a magnesium-containing silicate mineral collected from a deep-sea hydrothermal vent, and its crystal structure presents a unique layered structure with a large number of micropores and channels, which can provide abundant adsorption sites for glutamate, thereby achieving adsorption and separation of glutamate; Step 3: placing the flocculated fermentation liquid in an electromagnetic field environment generated by an electromagnet, with the north and south poles of the electromagnet placed horizontally so that the magnetic field direction in the fermentation liquid is horizontal from left to right, adjusting the current size and direction of the electromagnet to aggregate and separate the suspended matter with charge in the fermentation liquid; Step 4: applying ultrasound to the fermentation liquid treated by the electromagnetic field until the suspended matter is loosened, dispersed and separated from the fermentation liquid; Step 5: Introduce the fermentation liquid treated with ultrasound into the cyclone separator tangentially, and use the principle of fluid mechanics to make the fermentation liquid form a cyclone in the separator, increase the residence time of the suspended matter in the separator, and the heavier suspended matter is thrown to the wall and discharged from the bottom, and the lighter liquid forms a central upwelling flow and flows out from the top, and the liquid at the top is collected; Step six, prepare the electrostatic adsorption material, add the composite material to the fermentation liquid after cyclone separation, the addition amount is 5g-8g per liter of fermentation liquid, and use electric field induced precipitation technology combined with biotechnology, use microorganisms to enhance the electrostatic adsorption and precipitation effects, react for 1.5h-2h at a temperature of 32°C-35°C and a pH value of 7-7.2 to obtain pretreated liquid fertilizer.

[0005] As a further scheme of the present invention: in the step 1, the fermentation broth is mixed with the treated Bacillus subtilis in a volume ratio of 100:1-5, and the reaction is carried out for 1h-3h at a temperature of 25°C-35°C and a pH of 7-8.

[0006] As a further scheme of the present invention: in the step 1, a soil sample from a farmland is selected to prepare a Bacillus subtilis culture solution, the soil sample is mixed with sterile water and stirred evenly, and then gradient dilution is performed, and solutions of different dilutions are coated on a solid culture medium, the solid culture medium contains glucose, peptone, sodium chloride, ammonium sulfate and potassium dihydrogen phosphate, the coated culture medium is placed in a constant temperature incubator, and cultured at a temperature of 37°C-39°C for 24h-48h, colonies with typical morphological characteristics of Bacillus subtilis are selected from the grown colonies, and further purification and culture are performed, the purified colonies are inoculated into a liquid culture medium, and cultured in a shaker at a temperature of 30°C-33°C and a rotation speed of 180r / min for 12h-24h to obtain a Bacillus subtilis culture solution, and a centrifuge is used to centrifuge at a rotation speed of 3000r / min-3500r / min for 5min-8min to collect the bacteria.

[0007] As a further scheme of the present invention: in the step 1, after the Bacillus subtilis culture solution is centrifuged to obtain bacterial cells, the Bacillus subtilis is treated with a nitrogen mustard chemical mutagen, and the mutagen with a concentration of 0.5 mg / L-0.8 mg / L is co-cultured with the Bacillus subtilis at a temperature of 30°C-33°C for 4h-5h, and then the cultured Bacillus subtilis is centrifuged in a specific centrifuge at a speed of 2000r / min-2500r / min for 5min-8min to collect the bacterial cells.

[0008] As a further solution of the present invention: in the step 2, the high molecular polymer is polymerized by selecting methyl methacrylate and butyl acrylate as monomers under the action of ammonium persulfate initiator, the reaction temperature is 60°C-70°C, the reaction time is 8h-9h, and the polymer obtained after the reaction is chemically modified by reacting with concentrated sulfuric acid at 60°C-65°C for 1.5h-2.0h, and sulfonic acid active groups are introduced into its molecular structure.

[0009] As a further scheme of the present invention: in the step 2, the mineral material and the chemically modified high molecular polymer reaction container are placed in a glass container, mixed in a mass ratio of 1:3-4, and an ethanol solvent is added, and the reaction is stirred at a temperature of 80°C-100°C for 6h-7h, and the product after the reaction is filtered, washed and dried.

[0010] As a further solution of the present invention: in step three, the current magnitude and direction of the electromagnet are adjusted so that the electromagnetic field strength ranges from 800G to 2500G and the frequency ranges from 40Hz to 60Hz.

[0011] As a further solution of the present invention: in the step 4, the ultrasonic frequency is 30kHz-50kHz, the energy output is 80W-120W, and the treatment is carried out for 1h-2h at a temperature of 30℃-40℃ and a pH value of 6.5-7.5.

[0012] As a further solution of the present invention: in the step 5, the fermentation liquid is introduced into the cyclone separator tangentially at a flow rate of 4m / s-7m / s, so that the fermentation liquid forms a cyclone in the separator, and the residence time of the suspended matter in the separator is increased to 8min-15min.

[0013] As a further solution of the present invention: in the step six, polypyrrole is selected as the conductive polymer material for preparing the electrostatic adsorption material, and it is dissolved in N,N-dimethylformamide solvent to form a solution with a concentration of 0.5 mol / L-0.8 mol / L, and then nano-scale aluminum oxide particles are added to the solution, and the mass ratio of polypyrrole to aluminum oxide is 5:1. The particles are dispersed by stirring and ultrasonic treatment, and then the mixed solution is dried at a temperature of 60°C-70°C and a relative humidity of 40%-43% to form a composite material with electrostatic adsorption properties.

[0014] By adopting the above technical solution, compared with the prior art, the beneficial effects of the present invention are: 1. The present invention combines magnesium-containing silicate minerals from the vicinity of deep-sea hydrothermal vents with specially modified high-molecular polymers to form a composite material with a specific spatial configuration and functional groups. The composite material formed by the new mineral material of magnesium-containing silicate minerals and the chemically modified high-molecular polymers provides a large number of adsorption sites for glutamate by virtue of its unique layered structure and abundant micropores and channels, greatly improving the adsorption capacity of glutamate. The high-molecular polymer introduced with sulfonic acid active groups after being modified with concentrated sulfuric acid can form a specific chemical bond with glutamate, further enhancing the specificity and stability of adsorption, and can efficiently adsorb glutamate and separate it from other impurities, effectively removing impurities in the fermentation liquid, further enhancing the adsorption capacity of glutamate, improving the purity of the liquid fertilizer, and greatly improving the utilization value of the glutamate fermentation liquid; 2. The present invention prepares Bacillus subtilis by selecting soil samples from farmland, utilizing common and easily available resources, reducing costs, and subjecting Bacillus subtilis to chemical mutation treatment with nitrogen mustards, so that it can specifically flocculate fixed suspended matter in glutamate fermentation broth. Under specific culture conditions, the specific substances secreted by the mutated Bacillus subtilis interact with the fixed suspended matter. The mutated Bacillus subtilis can produce substances with high-efficiency flocculation effects, which are combined with the fixed suspended matter in the fermentation broth to form larger flocs. This flocculation effect makes it easier for the fixed suspended matter to be separated by subsequent processing steps, reducing the adverse effects of impurities on the subsequent preparation of liquid fertilizers, and greatly improving the efficiency of preparing high-quality liquid fertilizers; 3. The present invention generates an electromagnetic field through a specific electromagnet, and by accurately adjusting the current size and direction, and controlling the magnetic field within a certain intensity and frequency range, this electromagnetic field environment can produce a specific force on the charged suspended matter in the fermentation liquid, prompting it to further aggregate and separate. The process can be accurately adjusted according to the suspended matter of different properties and sizes, greatly improving the accuracy and pertinence of the separation. The new ultrasonic transducer applies ultrasonic waves with a specific frequency and waveform combination, and treats the fermentation liquid under specific temperature and pH conditions. This ultrasonic treatment can effectively break the binding force between the suspended matter and the fermentation liquid, loosen and disperse the suspended matter, and greatly improve the separation efficiency. The unique cyclone structure separator uses the principle of fluid mechanics to introduce the fermentation liquid tangentially at a specific flow rate, forming a strong cyclone in the separator, increasing the residence time of the suspended matter, and improving the separation effect, providing a solid guarantee for the preparation of high-quality liquid fertilizers. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the method steps in an embodiment of the present invention; Figure 2 Schematic diagram for comparison of embodiments of the present invention. DETAILED DESCRIPTION

[0016] 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.

[0017] 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.

[0018] Please see attached Figure 1 -Attached Figure 2 The present invention provides a pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid, and the pretreatment process comprises the following specific steps: Step 1, preparing a Bacillus subtilis culture solution, treating the culture solution to collect Bacillus subtilis cells, then treating the Bacillus subtilis with a nitrogen mustard chemical mutagen, then collecting the cells by centrifugation, placing the fermentation solution and the treated Bacillus subtilis in a constant temperature shaking incubator for reaction, so that the fixed suspended matter in the fermentation solution is flocculated; Step 2: prepare a specific adsorption material, react a mineral material with a modified high molecular polymer to form a composite material with a specific spatial configuration and functional groups. The mineral material is a magnesium-containing silicate mineral collected from a deep-sea hydrothermal vent, and its crystal structure presents a unique layered structure with a large number of micropores and channels, which can provide abundant adsorption sites for glutamate, thereby achieving adsorption and separation of glutamate; Step 3: placing the flocculated fermentation liquid in an electromagnetic field environment generated by an electromagnet, with the north and south poles of the electromagnet placed horizontally so that the magnetic field direction in the fermentation liquid is horizontal from left to right, adjusting the current size and direction of the electromagnet to aggregate and separate the suspended matter with charge in the fermentation liquid; Step 4: applying ultrasound to the fermentation liquid treated by the electromagnetic field until the suspended matter is loosened, dispersed and separated from the fermentation liquid; Step 5: Introduce the fermentation liquid treated with ultrasound into the cyclone separator tangentially, and use the principle of fluid mechanics to make the fermentation liquid form a cyclone in the separator, increase the residence time of the suspended matter in the separator, and the heavier suspended matter is thrown to the wall and discharged from the bottom, and the lighter liquid forms a central upwelling flow and flows out from the top, and the liquid at the top is collected; Step six, prepare the electrostatic adsorption material, add the composite material to the fermentation liquid after cyclone separation, the addition amount is 5g-8g per liter of fermentation liquid, and use electric field induced precipitation technology combined with biotechnology, use microorganisms to enhance the electrostatic adsorption and precipitation effects, react for 1.5h-2h at a temperature of 32°C-35°C and a pH value of 7-7.2 to obtain pretreated liquid fertilizer.

[0019] In one embodiment of the present invention: in step 1, the fermentation broth is mixed with the treated Bacillus subtilis in a volume ratio of 100:1-5, and the reaction is carried out for 1h-3h at a temperature of 25°C-35°C and a pH of 7-8.

[0020] In one embodiment of the present invention: In step 1, a soil sample from a farmland is selected to prepare a Bacillus subtilis culture solution, the soil sample is mixed with sterile water and stirred evenly, and then gradient dilution is performed, and solutions of different dilutions are applied on a solid culture medium, the solid culture medium contains glucose, peptone, sodium chloride, ammonium sulfate and potassium dihydrogen phosphate, the applied culture medium is placed in a constant temperature incubator, and cultured at a temperature of 37°C-39°C for 24h-48h, colonies with typical morphological characteristics of Bacillus subtilis are selected from the grown colonies, and further purification and culture are performed, the purified colonies are inoculated into a liquid culture medium, and cultured in a shaker at a temperature of 30°C-33°C and a rotation speed of 180r / min for 12h-24h to obtain a Bacillus subtilis culture solution, and a centrifuge is used to centrifuge at a rotation speed of 3000r / min-3500r / min for 5min-8min to collect the bacteria.

[0021] In one embodiment of the present invention: in step 1, after the Bacillus subtilis culture solution is centrifuged to obtain bacterial cells, the Bacillus subtilis is treated with a nitrogen mustard chemical mutagen, and the mutagen with a concentration of 0.5 mg / L-0.8 mg / L is co-cultured with the Bacillus subtilis at a temperature of 30°C-33°C for 4h-5h, and then the cultured Bacillus subtilis is centrifuged in a specific centrifuge at a speed of 2000r / min-2500r / min for 5min-8min to collect the bacterial cells.

[0022] In one embodiment of the present invention: in step 2, the high molecular polymer is polymerized by selecting methyl methacrylate and butyl acrylate as monomers under the action of ammonium persulfate initiator, the reaction temperature is 60°C-70°C, the reaction time is 8h-9h, and the polymer obtained after the reaction is chemically modified by reacting with concentrated sulfuric acid at 60°C-65°C for 1.5h-2.0h to introduce sulfonic acid active groups into its molecular structure.

[0023] In one embodiment of the present invention: in step 2, the mineral material and the chemically modified high molecular polymer reaction container are placed in a glass container, mixed in a mass ratio of 1:3-4, and an ethanol solvent is added, and the reaction is stirred at a temperature of 80°C-100°C for 6h-7h, and the product after the reaction is filtered, washed and dried.

[0024] In one embodiment of the present invention: in step three, the current magnitude and direction of the electromagnet are adjusted so that the electromagnetic field strength ranges from 800G to 2500G and the frequency ranges from 40Hz to 60Hz.

[0025] In one embodiment of the present invention: in step 4, the ultrasonic frequency is 30kHz-50kHz, the energy output is 80W-120W, and the treatment is carried out for 1h-2h at a temperature of 30°C-40°C and a pH value of 6.5-7.5.

[0026] In one embodiment of the present invention: in step five, the fermentation liquid is introduced into the cyclone separator tangentially at a flow rate of 4m / s-7m / s, so that the fermentation liquid forms a cyclone in the separator, and the residence time of the suspended matter in the separator is increased to 8min-15min.

[0027] In one embodiment of the present invention: In step six, polypyrrole is selected as the conductive polymer material for preparing the electrostatic adsorption material, and it is dissolved in N,N-dimethylformamide solvent to form a solution with a concentration of 0.5 mol / L-0.8 mol / L, and then nano-scale aluminum oxide particles are added to the solution, and the mass ratio of polypyrrole to aluminum oxide is 5:1. The solution is dispersed by stirring and ultrasonic treatment, and then the mixed solution is dried at a temperature of 60°C-70°C and a relative humidity of 40%-43% to form a composite material with electrostatic adsorption properties.

[0028] Example 1, please refer to the attached Figure 1 -Attached Figure 2First, prepare the culture solution of Bacillus subtilis. Select soil samples from farmland and mix them with sterile water, stir them evenly, and then dilute them in a gradient manner. Take solutions of different dilutions and spread them on a solid culture medium containing glucose, peptone, sodium chloride, ammonium sulfate and potassium dihydrogen phosphate. Place them in a constant temperature incubator and culture them at 38°C for 48 hours. Select colonies with typical morphological characteristics of Bacillus subtilis for purification and culture. Inoculate the purified colonies into liquid culture medium and culture them in a shaker at 33°C and 180 r / min for 24 hours to obtain the culture solution of Bacillus subtilis. Centrifuge them at 3500 r / min for 8 minutes to collect the culture solution. The cells were collected, and then the Bacillus subtilis was treated with a nitrogen mustard chemical mutagen, and the mutagen with a concentration of 0.8 mg / L was co-cultured with the Bacillus subtilis at a temperature of 33°C for 5 hours, and then the cultured Bacillus subtilis was centrifuged in a specific centrifuge at a speed of 2500r / min for 8 minutes to collect the cells, and then the fermentation broth was mixed with the treated Bacillus subtilis at a volume ratio of 100:3, and reacted at a temperature of -35°C and a pH value of 7 for 2 hours to flocculate the fixed suspended matter in the fermentation broth, and then a specific adsorption material was prepared, and methyl methacrylate and butyl acrylate were selected as monomers. The polymerization reaction was carried out at 60°C for 8 hours under the action of ammonium persulfate initiator. The polymer obtained after the reaction was chemically modified by reacting with concentrated sulfuric acid at 60°C for 2.0 hours, and sulfonic acid active groups were introduced into its molecular structure. The magnesium silicate minerals collected from deep-sea hydrothermal vents were mixed with the chemically modified high molecular polymer in a mass ratio of 1:4 in a glass container, and ethanol solvent was added. The reaction was stirred at 90°C for 7 hours. The reaction product was filtered, washed and dried. After that, the flocculated fermentation liquid was placed in an electromagnetic field environment generated by an electromagnet, and the current size and direction of the electromagnet were adjusted so that the electromagnetic field The intensity range is 2000G and the frequency is 60Hz. Subsequently, ultrasonic waves are applied to the fermented liquid treated by electromagnetic field. The ultrasonic frequency is 50kHz and the energy output is 100W. The fermented liquid is treated for 2h at a temperature of 35℃ and a pH value of 7.0. Then, the fermented liquid treated by ultrasonic wave is introduced into the cyclone separator at a flow rate of 5m / s to form a cyclone in the separator. The residence time of the suspended matter in the separator is increased to 12min. The liquid at the top is collected. Finally, the electrostatic adsorption material is prepared. Polypyrrole is selected as the conductive polymer material and dissolved in N,N-dimethylformamide solvent to form a concentration of 0.8mol / L solution, then add nano-aluminum trioxide particles to the solution, the mass ratio of polypyrrole to aluminum trioxide is 5:1, disperse it by stirring and ultrasonic treatment, then dry the mixed solution at a temperature of 60℃ and a relative humidity of 40% to form a composite material with electrostatic adsorption performance, add the composite material to the fermentation liquid after cyclone separation, the addition amount is 5g per liter of fermentation liquid, and use electric field induced precipitation technology combined with biotechnology, use microorganisms to enhance electrostatic adsorption and precipitation effects, react at a temperature of 35℃ and a pH value of 7 for 1.5h to obtain pretreated liquid fertilizer. .

[0029] Example 2, please refer to the attached Figure 1 -Attached Figure 2First, a Bacillus subtilis culture solution was prepared. Soil samples from an apple orchard were selected and mixed with sterile water and then diluted in a gradient manner. Solutions of different dilutions were spread on a solid culture medium containing glucose, peptone, sodium chloride, ammonium sulfate and dipotassium hydrogen phosphate, and cultured in a constant temperature incubator at 38°C for 48 hours. Colonies with typical morphological characteristics of Bacillus subtilis were selected for purification and culture. The purified colonies were inoculated into a liquid culture medium and cultured in a shaker at a temperature of 33°C and a speed of 180 r / min for 24 hours to obtain a Bacillus subtilis culture solution, which was then centrifuged at a speed of 3500 r / min for 8 min to collect the bacterial cells, then use nitrogen mustard chemical mutagen to treat Bacillus subtilis, co-culture the mutagen with a concentration of 0.8 mg / L and Bacillus subtilis at a temperature of 33°C for 5 hours, then centrifuge the cultured Bacillus subtilis in a specific centrifuge at a speed of 2500r / min for 8 minutes, collect the bacterial cells, then mix the fermentation broth with the treated Bacillus subtilis at a volume ratio of 100:3, react for 2 hours at a temperature of -35°C and a pH value of 7, so that the fixed suspended matter in the fermentation broth is flocculated, and then prepare a specific adsorption material, select ethyl methacrylate and amyl acrylate The ester was used as a monomer and reacted at 55°C for 8 hours under the action of sodium persulfate initiator for polymerization. The polymer obtained after the reaction was chemically modified by reacting with concentrated hydrochloric acid at 55°C for 2.0 hours, and a carboxyl active group was introduced into its molecular structure. The montmorillonite mineral in the deep sea and the chemically modified high molecular polymer were mixed in a glass container at a mass ratio of 1:3, and propanol solvent was added. The reaction was stirred at a temperature of 80°C for 7 hours. The product after the reaction was filtered, washed and dried. After that, the flocculated fermentation liquid was placed in an electromagnetic field environment generated by an electromagnet, and the current size and direction of the electromagnet were adjusted so that the electromagnetic field The intensity range is 2000G and the frequency is 60Hz. Subsequently, ultrasonic waves are applied to the fermented liquid treated by electromagnetic field. The ultrasonic frequency is 50kHz and the energy output is 100W. The fermented liquid is treated for 2h at a temperature of 35℃ and a pH value of 7.0. Then, the fermented liquid treated by ultrasonic wave is introduced into the cyclone separator at a flow rate of 5m / s to form a cyclone in the separator. The residence time of the suspended matter in the separator is increased to 12min. The liquid at the top is collected. Finally, the electrostatic adsorption material is prepared. Polyaniline is selected as the conductive polymer material and dissolved in N-methylpyrrolidone solvent to form a concentration of 0.8mol / L solution, then add nano-scale silica particles to the solution, the mass ratio of polyaniline to silica is 5:1, disperse it by stirring and ultrasonic treatment, then dry the mixed solution at a temperature of 60°C and a relative humidity of 40% to form a composite material with electrostatic adsorption performance, add the composite material to the fermentation liquid after cyclone separation, and add 5g per liter of fermentation liquid. At the same time, use electric field induced precipitation technology combined with biotechnology, use microorganisms to enhance electrostatic adsorption and precipitation effects, react at a temperature of 35°C and a pH value of 7 for 1.5 hours to obtain pretreated liquid fertilizer. .

[0030] Example 3, please refer to the attached Figure 1 -Attached Figure 2First, polyaluminium chloride was used as a flocculant to replace the flocculation treatment. Polyaluminium chloride is an inorganic polymer coagulant. It is an inorganic polymer water treatment agent with a large molecular weight and a high charge produced by the bridging effect of hydroxide ions and the polymerization effect of multivalent anions. It can flocculate the fixed suspended matter in the fermentation broth. Then, specific adsorption materials were prepared. Methyl methacrylate and butyl acrylate were selected as monomers. The polymerization reaction was carried out at 60°C for 8 hours under the action of ammonium persulfate initiator. The polymer obtained after the reaction was chemically modified by reacting with concentrated sulfuric acid at 60°C for 2.0 hours. Sulfonic acid active groups are introduced into the substructure, and magnesium silicate minerals collected from deep-sea hydrothermal vents are mixed with chemically modified high molecular polymers in a mass ratio of 1:4 in a glass container, and ethanol solvent is added. The reaction is stirred at 90°C for 7 hours. The reaction product is filtered, washed and dried. Then, the flocculated fermentation liquid is placed in an electromagnetic field environment generated by an electromagnet. The north and south poles of the electromagnet are placed horizontally so that the magnetic field direction in the fermentation liquid is horizontal from left to right. The current size and direction of the electromagnet are adjusted to aggregate and separate the charged suspended matter in the fermentation liquid. Subsequently, Ultrasonic waves were applied to the fermentation liquid treated by electromagnetic field, with an ultrasonic frequency of 50kHz and an energy output of 100W. The fermentation liquid was treated for 2 hours at a temperature of 35°C and a pH value of 7.0. Then, the fermentation liquid treated by ultrasonic wave was introduced into a cyclone separator at a flow rate of 5m / s to form a cyclone in the separator, and the residence time of the suspended matter in the separator was increased to 12min. The liquid at the top was collected. Finally, an electrostatic adsorption material was prepared, and polypyrrole was selected as the conductive polymer material, which was dissolved in an N,N-dimethylformamide solvent to form a solution with a concentration of 0.8mol / L. Then, nano-scale aluminum oxide particles are added to the solution, with a mass ratio of polypyrrole to aluminum oxide of 5:1. The particles are dispersed by stirring and ultrasonic treatment, and the mixed solution is then dried at 60°C and 40% relative humidity to form a composite material with electrostatic adsorption properties. The composite material is added to the fermentation broth after cyclone separation, with an addition amount of 5 g per liter of fermentation broth. At the same time, electric field induced precipitation technology is combined with biotechnology, and microorganisms are used to enhance the electrostatic adsorption and precipitation effects. The mixture is reacted for 1.5 hours at 35°C and pH 7 to obtain pretreated liquid fertilizer.

[0031] Example 4, please refer to the attached Figure 1 -Attached Figure 2First, a Bacillus subtilis culture solution was prepared. Soil samples from farmland were selected and mixed with sterile water, and then gradiently diluted. Solutions of different dilutions were spread on a solid culture medium containing glucose, peptone, sodium chloride, ammonium sulfate and potassium dihydrogen phosphate, and cultured in a constant temperature incubator at 38°C for 48 hours. Colonies with typical morphological characteristics of Bacillus subtilis were selected for purification and culture. The purified colonies were inoculated into a liquid culture medium and cultured in a shaker at a temperature of 33°C and a speed of 180 r / min for 24 hours to obtain a Bacillus subtilis culture solution. The bacteria were then collected by centrifugation at a speed of 3500 r / min for 8 minutes. Then, the Bacillus subtilis was treated with a nitrogen mustard chemical mutagen to obtain a concentration of 500 g / cm2. 0.8 mg / L of mutagen was co-cultured with Bacillus subtilis at 33°C for 5 hours, then the cultured Bacillus subtilis was centrifuged in a specific centrifuge at a speed of 2500 r / min for 8 minutes, the bacteria were collected, and then the fermentation broth was mixed with the treated Bacillus subtilis at a volume ratio of 100:3, and reacted at a temperature of -35°C and a pH value of 7 for 2 hours to allow the fixed suspended matter in the fermentation broth to flocculate, then, a specific adsorption material was prepared, methyl methacrylate and butyl acrylate were selected as monomers, and a polymerization reaction was carried out at 60°C for 8 hours under the action of ammonium persulfate initiator, and the polymer obtained after the reaction was chemically modified by reacting with concentrated sulfuric acid at 60°C for 2.0 hours, and at its molecular Sulfonic acid active groups are introduced into the structure, and then magnesium silicate minerals collected from deep-sea hydrothermal vents are mixed with chemically modified high molecular polymers in a mass ratio of 1:4 in a glass container, and ethanol solvent is added, and the reaction is stirred at 90°C for 7 hours. The reaction product is filtered, washed and dried, and ultrasonic waves are applied to the fermentation liquid treated with an electromagnetic field. The fermentation liquid treated with an electromagnetic field is allowed to stand for 2 hours to allow the suspended matter to settle naturally. Then, the fermentation liquid that has been treated with static sedimentation is introduced tangentially into a cyclone separator at a flow rate of 5 m / s to form a cyclone in the separator, increasing the residence time of the suspended matter in the separator to 12 minutes, and collecting the liquid on the top. Finally, an electrostatic adsorption material is prepared, and polypyrrole is selected as the conductive The electropolymer material is dissolved in N,N-dimethylformamide solvent to form a solution with a concentration of 0.8 mol / L, and then nano-aluminum oxide particles are added to the solution, the mass ratio of polypyrrole to aluminum oxide is 5:1, and the solution is dispersed by stirring and ultrasonic treatment. The mixed solution is then dried at a temperature of 60°C and a relative humidity of 40% to form a composite material with electrostatic adsorption performance. The composite material is added to the fermentation liquid after cyclone separation, and the addition amount is 5g per liter of fermentation liquid. At the same time, electric field induced precipitation technology is combined with biotechnology, and microorganisms are used to enhance the electrostatic adsorption and precipitation effects. The reaction is carried out at a temperature of 35°C and a pH value of 7 for 1.5 hours to obtain a pretreated liquid fertilizer.

[0032] Design of the experiment: Experimental materials: several portions of glutamic acid fermentation broth from the same source, ensuring that the parameters of the initial fermentation broth are basically the same, chemical reagents and instruments required for the experiment, high-performance liquid chromatography for detecting glutamic acid content, specific analytical instruments for determining impurity content, microscopes, etc.; Experimental steps: Preparation stage: Four equal amounts of glutamate fermentation broth were taken and marked as experimental group 1 (corresponding to Example 1), experimental group 2 (corresponding to Example 2), experimental group 3 (corresponding to Example 3), and experimental group 4 (corresponding to Example 4).

[0033] The initial glutamic acid fermentation liquid is tested for various indicators as the baseline data. The initial glutamic acid content, impurity content, fixed suspended solids content and the preliminary estimated liquid fertilizer purity are recorded.

[0034] Processing stage: Four portions of fermentation broth were treated according to the processes of Example 1 to Example 4 respectively.

[0035] Detection phase: Glutamic acid adsorption detection: The glutamate content in the treated fermentation broth was determined by high performance liquid chromatography. The glutamate adsorption amount was calculated by the formula: initial glutamate content - glutamate content after treatment. For example, if the glutamate content in the initial fermentation broth was 100 g / L and the glutamate content in the fermentation broth of the experimental group 1 after treatment was 20 g / L, the glutamate adsorption amount was 80 g / L. Impurity removal rate detection: The impurity content is measured by a specific analytical instrument, and the impurity removal rate is calculated as follows: (initial impurity content - impurity content after treatment) / initial impurity content × 100%; Fixed suspended solids removal effect test: Use a microscope to observe and count the number of fixed suspended solids. The removal effect of fixed suspended solids can be evaluated by the difference in the number of suspended solids before and after treatment and the removal ratio. When the number of fixed suspended solids in the initial fermentation broth is 1000 / mL and the number of fixed suspended solids in the fermentation broth of experimental group 1 after treatment is 100 / mL, the removal ratio is (1000-100) / 1000×100%=90%; Liquid fertilizer purity testing: The purity of liquid fertilizers is determined using high performance liquid chromatography (HPLC) combined with specific testing methods; As attached Figure 2As shown, Example 1 is superior to Examples 2, 3 and 4 in terms of glutamate adsorption, impurity removal rate, fixed suspended solids removal effect and liquid fertilizer purity. The glutamate adsorption of Example 1 is as high as 85.2 g / L, the impurity removal rate is 82.3%, the fixed suspended solids removal ratio is 92.5%, and the liquid fertilizer purity is 96.8%. In comparison, the indicators of other Examples have decreased to varying degrees, which fully proves that the process of Example 1 has a better effect in the pretreatment process of preparing liquid fertilizer using glutamate fermentation broth.

[0036] 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 pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid, characterized in that: The pretreatment process comprises the following specific steps: Step 1, preparing a Bacillus subtilis culture solution, treating the culture solution to collect Bacillus subtilis cells, then treating the Bacillus subtilis with a nitrogen mustard chemical mutagen, then collecting the cells by centrifugation, placing the fermentation solution and the treated Bacillus subtilis in a constant temperature shaking incubator for reaction, so that the fixed suspended matter in the fermentation solution is flocculated; Step 2: preparing a specific adsorption material, reacting a mineral material with a modified high molecular polymer, wherein the mineral material is a magnesium-containing silicate mineral collected from a deep-sea hydrothermal vent, which provides an adsorption site for glutamate; Step 3: placing the flocculated fermentation liquid in an electromagnetic field environment generated by an electromagnet, with the north and south poles of the electromagnet placed horizontally so that the magnetic field direction in the fermentation liquid is horizontal from left to right, adjusting the current size and direction of the electromagnet to aggregate and separate the suspended matter with charge in the fermentation liquid; Step 4: applying ultrasound to the fermentation liquid treated by the electromagnetic field until the suspended matter is loosened, dispersed and separated from the fermentation liquid; Step 5, introducing the fermentation liquid treated with ultrasound into the cyclone separator tangentially, so that the fermentation liquid forms a cyclone in the separator, increasing the residence time of the suspended matter in the separator, the heavier suspended matter is thrown to the wall and discharged from the bottom, the lighter liquid forms a central upwelling flow and flows out from the top, and the liquid at the top is collected; Step six, prepare the electrostatic adsorption material, add the composite material to the fermentation liquid after cyclone separation, the addition amount is 5g-8g per liter of fermentation liquid, and use electric field induced precipitation technology combined with biotechnology, use microorganisms to enhance the electrostatic adsorption and precipitation effects, react for 1.5h-2h at a temperature of 32°C-35°C and a pH value of 7-7.2 to obtain pretreated liquid fertilizer.

2. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step 1, the fermentation liquid is mixed with the treated Bacillus subtilis in a volume ratio of 100:1-5, and the mixture is reacted for 1h-3h at a temperature of 25°C-35°C and a pH of 7-8.

3. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step 1, a soil sample from a farmland is selected to prepare a Bacillus subtilis culture solution, the soil sample is mixed with sterile water and stirred evenly, and then gradient dilution is performed, and solutions of different dilutions are applied on a solid culture medium, the solid culture medium contains glucose, peptone, sodium chloride, ammonium sulfate and potassium dihydrogen phosphate, the applied culture medium is placed in a constant temperature incubator, and cultured at a temperature of 37° C.-39° C. for 24 h-48 h, colonies with typical morphological characteristics of Bacillus subtilis are selected from the grown colonies, and further purification and culture are performed, the purified colonies are inoculated into a liquid culture medium, and cultured in a shaking incubator at a temperature of 30° C.-33° C. and a rotation speed of 180 r / min for 12 h-24 h to obtain a Bacillus subtilis culture solution, and a centrifuge is used to centrifuge at a rotation speed of 3000 r / min-3500 r / min for 5 min-8 min to collect the bacteria.

4. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step 1, after the Bacillus subtilis culture solution is centrifuged to obtain bacterial cells, the Bacillus subtilis is treated with a nitrogen mustard chemical mutagen, and the mutagen with a concentration of 0.5 mg / L-0.8 mg / L is co-cultured with the Bacillus subtilis at a temperature of 30° C.-33° C. for 4 h-5 h, and then the cultured Bacillus subtilis is centrifuged in a specific centrifuge at a speed of 2000 r / min-2500 r / min for 5 min-8 min to collect the bacterial cells.

5. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step 2, the polymer is polymerized by selecting methyl methacrylate and butyl acrylate as monomers under the action of ammonium persulfate initiator, the reaction temperature is 60°C-70°C, the reaction time is 8h-9h, and the polymer obtained after the reaction is chemically modified by reacting with concentrated sulfuric acid at 60°C-65°C for 1.5h-2.0h to introduce sulfonic acid active groups into its molecular structure.

6. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step 2, the mineral material and the chemically modified high molecular polymer reaction container are placed in a glass container, mixed at a mass ratio of 1:3-4, and an ethanol solvent is added. The reaction is stirred at a temperature of 80°C-100°C for 6h-7h, and the product after the reaction is filtered, washed and dried.

7. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step three, the current magnitude and direction of the electromagnet are adjusted so that the electromagnetic field strength ranges from 800G to 2500G and the frequency ranges from 40Hz to 60Hz.

8. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step 4, the ultrasonic frequency is 30kHz-50kHz, the energy output is 80W-120W, and the treatment is carried out for 1h-2h at a temperature of 30°C-40°C and a pH value of 6.5-7.

5.

9. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step 5, the fermentation liquid is introduced into the cyclone separator tangentially at a flow rate of 4 m / s-7 m / s, so that the fermentation liquid forms a cyclone in the separator, and the residence time of the suspended matter in the separator is increased to 8 min-15 min.

10. The pretreatment process for preparing liquid fertilizer using glutamic acid fermentation liquid according to claim 1, characterized in that: In the step six, polypyrrole is selected as the conductive polymer material for preparing the electrostatic adsorption material, and it is dissolved in N,N-dimethylformamide solvent to form a solution with a concentration of 0.5 mol / L-0.8 mol / L, and then nano-scale aluminum oxide particles are added to the solution, and the mass ratio of polypyrrole to aluminum oxide is 5:

1. The particles are dispersed by stirring and ultrasonic treatment, and then the mixed solution is dried at a temperature of 60°C-70°C and a relative humidity of 40%-43% to form a composite material with electrostatic adsorption properties.

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