Preparation method for improving soil fertility by producing liquid fertilizer from tylosin finished product liquid

Abstract

The invention discloses a preparation method for producing a liquid fertilizer by using a tylosin finished product liquid to improve soil fertility, and relates to the technical field of fertilizer preparation, and the preparation method comprises the steps of pretreatment of the tylosin finished product liquid, directional degradation of the finished product liquid, nutrition blending and stabilization treatment of the finished product fertilizer. The method has the advantages that ultrasonic treatment is performed on the fermentation tank in the fermentation period, the permeability of microbial cell membranes can be enhanced through the cavitation effect and the acoustic streaming effect generated by ultrasonic waves, sufficient contact between microorganisms and a substrate is promoted, the degradation efficiency of tylosin is improved, meanwhile, the metabolic activity of nitrogen-fixing bacteria and phosphate solubilizing bacteria can be promoted, and the degradation efficiency of tylosin is improved. The biochar composite thickening agent is added into the semi-finished product of the liquid fertilizer and is subjected to ultrasonic treatment, so that the thickening agent can be uniformly dispersed and a stable spatial network structure is constructed, the viscosity and the stability of the liquid fertilizer are effectively improved, and the layering phenomenon of the liquid fertilizer in the storage and transportation processes is prevented.

Description

Technical Field

[0001] The invention relates to the technical field of fertilizer preparation, in particular to a method for preparing liquid fertilizer by using tylosin finished product liquid to improve soil fertility. Background Art

[0002] In modern agricultural production, soil fertility plays a vital role in the growth and yield of crops. With the long-term and high-intensity agricultural planting activities, the loss of nutrients in the soil, the destruction of soil structure and the imbalance of microbial communities have become increasingly prominent, resulting in a gradual decline in soil fertility, which seriously affects the quality and yield of crops. In order to maintain and improve soil fertility, agricultural practitioners and scientific researchers have been actively exploring various effective fertilizers and soil improvement measures. Tylosin is an antibiotic widely used in animal husbandry. It is mainly used to prevent and treat mycoplasma infections and other diseases in livestock and poultry. It plays an important role in breeding production. During its production process, a certain amount of tylosin finished liquid will be produced. In addition to a small amount of tylosin residue, these finished liquids also contain many organic components produced during the fermentation process, microbial metabolic intermediates and other substances; In the existing technology of preparing fertilizer using tylosin finished liquid, the treatment of tylosin residual in the finished liquid is not perfect. Although tylosin may promote plant growth at a certain concentration, if the residual amount is too high and used for a long time, it may lead to accumulation of antibiotics in the soil, thereby inducing soil microorganisms to develop drug resistance, affecting the soil microecological balance, and there is a potential risk of being transmitted to humans through the food chain. When converting tylosin finished liquid into fertilizer, the current related technology often simply adds some conventional nutrients, lacks in-depth research on the synergistic effect between the components in the finished liquid and the added nutrients, resulting in the nutritional formula of the fertilizer being not scientific and reasonable, and unable to give full play to its maximum efficiency in improving soil fertility. To this end, we propose a preparation method for producing liquid fertilizer from tylosin finished liquid to improve soil fertility. Summary of the invention

[0003] The object of the present invention is to provide a method for preparing liquid fertilizer for improving soil fertility by using tylosin finished liquid.

[0004] In order to solve the problems raised in the above background technology, the present invention provides the following technical solutions: a method for preparing liquid fertilizer for improving soil fertility by using tylosin finished liquid, comprising pretreatment of tylosin finished liquid, directional degradation of finished liquid, nutrient blending and stabilization treatment of finished fertilizer, and the specific operation steps of the method for preparing liquid fertilizer for improving soil fertility by using tylosin finished liquid are as follows: Step 1, collecting the tylosin finished product liquid, adding water to dilute it and filtering it, and adding an adsorbent to it after filtering to prepare a tylosin pretreatment liquid; Step 2: transferring the tylosin pretreatment liquid to a reaction tank, adding microbial flora for fermentation, and simultaneously turning on an ultrasonic device for ultrasonic-assisted enhancement, and obtaining a tylosin fermentation liquid after the ultrasonication is completed; Step 3, adding nutrients and trace elements to the tylosin fermentation liquid, and then adding biologically active substances according to the proportion, stirring and mixing to obtain a liquid fertilizer semi-finished product; Step 4: Place the semi-finished liquid fertilizer into a reaction container, add a thickener and an emulsifier for stabilization, and after the treatment, add an antioxidant and mix to form a finished liquid fertilizer; Step 5: Take the finished liquid fertilizer for quality testing, including tylosin residue, heavy metal content, nutrient content and pH value.

[0005] As a further scheme of the present invention: in the step 1, the tylosin finished liquid is collected, diluted according to a volume ratio of tylosin to water of 1:200-300, stirred at a temperature of 30°C at a stirring speed of 150r / min-180r / min for 20min-25min, after the stirring and dilution is completed, it is filtered through a ceramic membrane filter with a pore size of 100um to remove large particle impurities, after the filtration is completed, a composite adsorbent is added thereto, the amount of the composite adsorbent added is 4%-6% of the total mass of the filtered solution, and stirred at a temperature of 30°C at a stirring speed of 160r / min-180r / min for 30min-45min, and after the stirring is completed, a tylosin pretreatment liquid is obtained.

[0006] As a further scheme of the present invention: in the step 1, the adsorbent is prepared by mixing specially treated graphene and mesoporous molecular sieve in a mass ratio of 3:2, the special treatment is to use a mixed solution of concentrated nitric acid and concentrated sulfuric acid to treat it at a temperature of 80°C for 3h-4h, and after the treatment, it is rinsed with deionized water to neutrality, and after the rinsing, it is refluxed with octadecyltriethoxysilane in a toluene solution for 6h to obtain specially treated graphene, and it is mixed with the mesoporous molecular sieve to prepare a composite adsorbent.

[0007] As a further solution of the present invention: in the step 2, the tylosin pretreatment liquid is transferred to a reaction tank, and a composite microbial flora is added, including tylosin efficient degradation bacteria, nitrogen-fixing bacteria and phosphate-solubilizing bacteria, which are composed in a ratio of 5:3:2. The composite microbial flora breaks down the tylosin molecules into small molecular organic acids and amino acids, and the nitrogen fixation reaction formula is:

[0008] In the above reaction, nitrogen in the air is converted into ammonia nitrogen after being treated by nitrogen-fixing bacteria.

[0009] As a further solution of the present invention: in the step 2, the composite microbial flora is transferred into a reaction tank, the temperature in the reaction tank is adjusted to 32°C-35°C, the pH value is adjusted to 6.8-7.2, the dissolved oxygen is controlled at 4mg / L-6mg / L, and aerobic fermentation treatment is carried out for 40h-48h. At the same time, the ultrasonic device is turned on, the frequency is set to 25kHz-30kHz, the power is 180W-220W, and the liquid in the reaction tank is intermittently ultrasonicated, working for 8min and stopping for 4min. After the ultrasonic treatment is completed, the tylosin fermentation liquid is obtained and stored for later use.

[0010] As a further solution of the present invention: in the step 3, 14g-16g potassium nitrate, 8g-9g diammonium phosphate, 3.5g-4g ferrous sulfate, 0.15g-0.2g boric acid, 0.08g-0.1g sodium molybdate and 0.045g-0.05g zinc sulfate are weighed per liter of tylosin fermentation liquid, and slowly added to the tylosin fermentation liquid under an environmental condition of 33°C-35°C, and a stirring device is turned on at the same time, and stirred at a stirring speed of 200r / min-220r / min for 20min-25min. After the stirring is completed, the biologically active substance is added, and stirred at a temperature of 30°C-35°C at a stirring speed of 230r / min for 15min to obtain a liquid fertilizer semi-finished product.

[0011] As a further scheme of the present invention: in the step three, the biologically active substance is prepared by copolymerization of N-isopropylacrylamide and acrylic acid. During the preparation process, under nitrogen protection, N-isopropylacrylamide, acrylic acid and cross-linking agent N,N'-methylenebisacrylamide are dissolved in deionized water at a mass ratio of 7:3:0.5, initiator ammonium persulfate and promoter tetramethylethylenediamine are added, and the reaction is carried out at a temperature of 30°C for 4 hours to prepare a hydrogel, in which metabolites extracted from a special halophilic archaea fermentation broth are encapsulated, and the encapsulation rate is 60%. The amount of microbial metabolites encapsulated by the hydrogel is 4.5% of the mass of the tylosin fermentation broth, in a soil environment.

[0012] As a further solution of the present invention: in the step 4, the liquid fertilizer semi-finished product is transferred into a reaction container with constant temperature and ultrasonic synergistic function, and a biochar composite thickener is added in an amount of 4%-6% of the total mass of the liquid fertilizer semi-finished product. At a temperature of 40°C, the mixture is stirred at a stirring rate of 300r / min for 10min. After the stirring is completed, the ultrasonic device is turned on for 5min, the ultrasonic frequency is set to 40kHz, and the ultrasonic power is set to 150W. After the ultrasonic treatment is completed, a polysaccharide emulsifier is added thereto in an amount of 6% of the total mass of the liquid fertilizer semi-finished product. 3%-4%, at a temperature of 50°C, use a high-speed shear emulsifier at a speed of 4800r / min for shearing emulsification for 9min-10min to form a uniform and stable emulsified system, add antioxidants after emulsification, and the amount added is 0.09%-0.15% of the total mass of the liquid fertilizer semi-finished product. After adding, stir the liquid fertilizer semi-finished product at a temperature of 35°C-40°C at a stirring speed of 280r / min-300r / min for 10min to evenly distribute the antioxidants in the liquid fertilizer system to obtain a liquid fertilizer product.

[0013] As a further solution of the present invention: in the step five, a full spectrum analyzer is used to scan and analyze the finished liquid fertilizer product, and its absorption spectrum characteristics in the ultraviolet-visible light-near infrared band are detected. The nutrient content range and abnormal substance interference are preliminarily judged according to the change of the absorption peak at a specific wavelength. The ultra-high performance liquid chromatography-tandem mass spectrometry technology is used to accurately determine the tylosin residue, the inductively coupled plasma mass spectrometry is used to detect the heavy metal content, and the precision pH meter is used to determine the pH value of the finished liquid fertilizer product, and the measurement error is controlled within ±0.02.

[0014] By adopting the above technical solution, compared with the prior art, the beneficial effects of the present invention are: 1. The present invention performs ultrasonic treatment on the fermentation tank during fermentation. The cavitation effect and acoustic flow effect generated by ultrasound can not only enhance the permeability of the microbial cell membrane, promote the full contact between the microorganism and the substrate, and improve the degradation efficiency of tylosin, but also promote the metabolic activity of nitrogen-fixing bacteria and phosphate-solubilizing bacteria. By adding a biochar composite thickener to the liquid fertilizer semi-finished product and performing ultrasonic treatment, the thickener can be evenly dispersed and a stable spatial network structure can be constructed, effectively improving the viscosity and stability of the liquid fertilizer, and preventing the stratification phenomenon during storage and transportation. By adding a polysaccharide emulsifier and an antioxidant to the liquid fertilizer semi-finished product for mixing, the liquid fertilizer can form a uniform and stable emulsified system, ensuring that the liquid fertilizer is The various nutrients and active substances in liquid fertilizer can exist stably and be easily absorbed by plants. The ingredients in antioxidants can effectively remove free radicals generated during the storage of liquid fertilizer, and at the same time can delay the oxidation and deterioration of fertilizer, thus extending the service life of liquid fertilizer. By combining a variety of nutrients with bioactive substances, a solid material foundation is laid for crop growth. The special hydrogel in the bioactive substances encapsulates microbial metabolites, which are not only rich in a variety of growth-promoting factors, but also synergistically act with nutrients to effectively activate a variety of physiological and biochemical processes in plants, promote root development, improve photosynthesis efficiency, etc., thereby stimulating plant growth vitality in all directions, significantly improving the effective utilization rate of soil fertility, and promoting the healthy growth of crops. 2. The present invention uses a special composite adsorbent to remove heavy metals and some residual impurities in the tylosin finished liquid, thereby reducing the difficulty of subsequent treatment and environmental risks. The composite microbial flora is fermented under the assistance of ultrasound to deeply degrade tylosin and convert it into harmless small-molecule organic acids and amino acids, which greatly reduces the possibility of antibiotic residue accumulation in the soil, effectively maintains the natural balance of the soil microbial community, and eliminates the problem of microbial resistance caused by excessive soil antibiotics. The potential channel for endangering human health through the food chain is cut off from the root. By using the synergistic effect of the biochar composite thickener and the polysaccharide emulsifier and cooperating with a specific operating method, a stable fertilizer system structure is constructed, which effectively curbs the common adverse phenomena such as stratification and precipitation of fertilizers during storage and transportation, ensures the uniformity and effectiveness of the fertilizer, and further enhances the antioxidant performance of the liquid fertilizer product by adding antioxidants, slows down its deterioration rate, and prolongs the shelf life. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the process of producing liquid fertilizer from tylosin finished liquid in an embodiment of the present invention; Figure 2 This is a schematic diagram for comparing the growth index results of the treatment groups in the embodiments of the present invention; Figure 3 This is a schematic diagram comparing the soil fertility results of the treatment groups in the embodiments of the present invention. DETAILED DESCRIPTION

[0016] The specific embodiments of the present invention are 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. 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] The present invention discloses a method for preparing liquid fertilizer for improving soil fertility by using tylosin finished liquid, which comprises pretreatment of tylosin finished liquid, directional degradation of finished liquid, nutrient blending and stabilization treatment of finished fertilizer. The specific operation steps of the method for preparing liquid fertilizer for improving soil fertility by using tylosin finished liquid are as follows: Step 1, collecting the tylosin finished product liquid, adding water to dilute it and filtering it, and adding an adsorbent to it after filtering to prepare a tylosin pretreatment liquid; Step 2: transferring the tylosin pretreatment liquid to a reaction tank, adding microbial flora for fermentation, and simultaneously turning on an ultrasonic device for ultrasonic-assisted enhancement, and obtaining a tylosin fermentation liquid after the ultrasonication is completed; Step 3, adding nutrients and trace elements to the tylosin fermentation liquid, and then adding biologically active substances according to the proportion, stirring and mixing to obtain a liquid fertilizer semi-finished product; Step 4: Place the semi-finished liquid fertilizer into a reaction container, add a thickener and an emulsifier for stabilization, and after the treatment, add an antioxidant and mix to form a finished liquid fertilizer; Step 5: Take the finished liquid fertilizer for quality testing, including tylosin residue, heavy metal content, nutrient content and pH value.

[0018] In one embodiment of the present invention: in step 1, collect tylosin finished liquid, dilute it according to the volume ratio of tylosin to water of 1:200-300, stir it at a temperature of 30°C at a stirring speed of 150r / min-180r / min for 20min-25min, after the stirring and dilution is completed, filter it through a ceramic membrane filter with a pore size of 100um to remove large particle impurities, after the filtration is completed, add a composite adsorbent thereto, the amount of the composite adsorbent added is 4%-6% of the total mass of the filtered solution, under a temperature of 30°C, stir it at a stirring speed of 160r / min-180r / min for 30min-45min, and after the stirring is completed, obtain a tylosin pretreatment liquid.

[0019] In one embodiment of the present invention: in step one, the adsorbent is prepared by mixing specially treated graphene and mesoporous molecular sieve in a mass ratio of 3:2, the special treatment is to use a mixed solution of concentrated nitric acid and concentrated sulfuric acid to treat it at a temperature of 80°C for 3h-4h, and then rinse it with deionized water to neutrality. After rinsing, it is refluxed with octadecyltriethoxysilane in a toluene solution for 6h to obtain specially treated graphene, which is then mixed with the mesoporous molecular sieve to form a composite adsorbent.

[0020] In one embodiment of the present invention: in step 2, the tylosin pretreatment liquid is transferred to a reaction tank, and a composite microbial flora is added, including tylosin efficient degradation bacteria, nitrogen-fixing bacteria and phosphate-solubilizing bacteria, which are composed according to a ratio of 5:3:2. The composite microbial flora breaks down the tylosin molecules into small molecular organic acids and amino acids, and the nitrogen fixation reaction formula is:

[0021] In the above reaction, nitrogen in the air is converted into ammonia nitrogen after being treated by nitrogen-fixing bacteria.

[0022] In one embodiment of the present invention: in step 2, the composite microbial flora is transferred into a reaction tank, the temperature in the reaction tank is adjusted to 32°C-35°C, the pH value is adjusted to 6.8-7.2, the dissolved oxygen is controlled at 4mg / L-6mg / L, and aerobic fermentation treatment is carried out for 40h-48h. At the same time, the ultrasonic device is turned on, the frequency is set to 25kHz-30kHz, the power is 180W-220W, and the liquid in the reaction tank is intermittently ultrasonicated, working for 8min and stopping for 4min. After the ultrasonic treatment is completed, the tylosin fermentation liquid is obtained and stored for later use.

[0023] In one embodiment of the present invention: in step three, 14g-16g potassium nitrate, 8g-9g diammonium phosphate, 3.5g-4g ferrous sulfate, 0.15g-0.2g boric acid, 0.08g-0.1g sodium molybdate and 0.045g-0.05g zinc sulfate are weighed per liter of tylosin fermentation broth, and slowly added to the tylosin fermentation broth under an environmental condition of 33°C-35°C, and a stirring device is turned on at the same time, and stirred at a stirring speed of 200r / min-220r / min for 20min-25min, and after stirring, biologically active substances are added, and stirred at a temperature of 30°C-35°C at a stirring speed of 230r / min for 15min to obtain a liquid fertilizer semi-finished product.

[0024] In one embodiment of the present invention: in step three, the bioactive substance is prepared by copolymerization of N-isopropylacrylamide and acrylic acid. During the preparation process, under nitrogen protection, N-isopropylacrylamide, acrylic acid and cross-linking agent N,N'-methylenebisacrylamide are dissolved in deionized water at a mass ratio of 7:3:0.5, initiator ammonium persulfate and promoter tetramethylethylenediamine are added, and the reaction is carried out at a temperature of 30°C for 4 hours to prepare a hydrogel, in which metabolites extracted from a special halophilic archaea fermentation broth are encapsulated, and the encapsulation rate is 60%. The amount of microbial metabolites encapsulated by the hydrogel is 4.5% of the mass of the tylosin fermentation broth, in a soil environment.

[0025] In one embodiment of the present invention: in step 4, the liquid fertilizer semi-finished product is transferred into a reaction container with constant temperature and ultrasonic synergistic function, and a biochar composite thickener is added in an amount of 4%-6% of the total mass of the liquid fertilizer semi-finished product. At a temperature of 40°C, the mixture is stirred at a stirring rate of 300r / min for 10 minutes. After the stirring is completed, the ultrasonic device is turned on for 5 minutes, the ultrasonic frequency is set to 40kHz, and the ultrasonic power is set to 150W. After the ultrasonic treatment is completed, a polysaccharide emulsifier is added thereto in an amount of 4%-6% of the total mass of the liquid fertilizer semi-finished product. 3%-4%, at a temperature of 50°C, use a high-speed shear emulsifier at a speed of 4800r / min for shearing emulsification for 9min-10min to form a uniform and stable emulsified system, add antioxidants after emulsification, and the amount added is 0.09%-0.15% of the total mass of the liquid fertilizer semi-finished product. After adding, stir the liquid fertilizer semi-finished product at a temperature of 35°C-40°C at a stirring speed of 280r / min-300r / min for 10min to evenly distribute the antioxidants in the liquid fertilizer system to obtain a liquid fertilizer product.

[0026] In one embodiment of the present invention: in step five, a full spectrum analyzer is used to scan and analyze the finished liquid fertilizer product, and its absorption spectrum characteristics in the ultraviolet-visible light-near infrared band are detected. The nutrient content range and abnormal substance interference are preliminarily judged according to the change of the absorption peak at a specific wavelength. The ultra-high performance liquid chromatography-tandem mass spectrometry technology is used to accurately determine the tylosin residue, the inductively coupled plasma mass spectrometry is used to detect the heavy metal content, and the precision pH meter is used to determine the pH value of the finished liquid fertilizer product, and the measurement error is controlled within ±0.02.

[0027] In one embodiment of the present invention: in step 1, after filtration, a composite adsorbent is added thereto, wherein the composite adsorbent is prepared by mixing specially treated graphene and mesoporous molecular sieve in a mass ratio of 3:2. During the treatment, an appropriate amount of graphene is placed in a reaction container, and a mixed solution of concentrated nitric acid and concentrated sulfuric acid (volume ratio of 1:3) is added, and the mixture is treated at a temperature of 80°C for 3h-4h. During the treatment, stirring is continued at a speed of 200r / min-300r / min to ensure that the graphene is fully in contact with the acid solution for oxidation modification. After the treatment, a large amount of deionized water is used to rinse it to neutrality, and the volume ratio of the rinsing water to the treatment liquid is 10:1-15:1. Multiple small-volume rinsing methods are used, and the p of the rinsing liquid is measured after each rinsing. H value, until the pH value stabilizes between 6.5-7.5. After rinsing, it is refluxed with octadecyltriethoxysilane in toluene solution for 6 hours, and the reflux temperature is controlled at 110℃-120℃. A condenser is used during the reflux process to ensure the recycling of toluene, and specially treated graphene is obtained. It is mixed with mesoporous molecular sieves to prepare a composite adsorbent. The amount of the composite adsorbent added is 4%-6% of the total mass of the filtered solution. At a temperature of 30℃, it is stirred at a stirring speed of 160r / min-180r / min for 30min-45min. During the stirring process, a slight bubbling stirring is performed by bottom air intake to make the adsorbent fully contact with the solution and improve the adsorption efficiency. After stirring, a tylosin pretreatment solution is obtained.

[0028] In one embodiment of the present invention: in step three, in the soil environment, when the temperature rises or the pH value changes, the hydrogel will undergo a volume phase change, thereby controlling the release of microbial metabolites. When the temperature is higher than its minimum critical solution temperature or the soil is acidic (pH <6.5), the hydrogel shrinks and releases the microbial metabolites, among which certain growth promoting factors in the microbial metabolites can promote the elongation of plant stems, and antioxidants can remove free radicals in the soil and protect plant roots from oxidative damage.

[0029] In one embodiment of the present invention: in step 4, the biochar composite thickener is prepared by compounding bamboo charcoal after high-temperature activation treatment and nano-montmorillonite in a mass ratio of 1:1, and then fully mixed and refined to an average particle size of 50nm-100nm by ball milling.

[0030] Example 1L of tylosin finished liquid was collected and diluted according to a volume ratio of tylosin to water of 1:250, that is, tylosin finished liquid was slowly added to 250L of deionized water, and stirred at a stirring speed of 165r / min for 22min at a temperature of 30°C to fully mix the solution. The diluted solution was filtered through a ceramic membrane filter with a pore size of 100um. The filtering device adopted a cross-flow filtration method, and the filtration pressure difference was set to 0.25MPa. During the filtration process, the filtration pressure and filtrate flow were monitored in real time. When the pressure difference rose to 0.3MPa or the filtrate flow dropped to 80% of the initial flow, the backwashing program was automatically started. The backwashing time was 4min and the backwashing pressure was 0.45MPa to restore the filtration performance of the filter and remove large particle impurities. After the filtration was completed, a composite adsorbent was added thereto. The composite adsorbent was made by mixing specially treated graphene and mesoporous molecular sieve in a mass ratio of 3:2. The special treatment process is as follows: Take an appropriate amount of graphene and place it in a reaction container, add a mixed solution of concentrated nitric acid and concentrated sulfuric acid (volume ratio 1:3), treat it at a temperature of 80°C for 3.5 hours, stir continuously during the treatment process, and the stirring speed is 250r / min to ensure that the graphene is fully in contact with the acid solution for oxidation modification. After the treatment, use a large amount of deionized water to rinse it to neutrality. The volume ratio of the rinse water volume to the treatment liquid is 12:1. Use multiple small rinses. After each rinse, measure the pH value of the rinse solution until the pH value stabilizes at around 7.0. After the rinse is completed, mix it with octadecane. Triethoxysilane was refluxed in a toluene solution for 6 hours, and the reflux temperature was controlled at 115°C. A condenser was used during the reflux process to ensure the recycling of toluene, and specially treated graphene was obtained. The graphene was mixed with a mesoporous molecular sieve to prepare a composite adsorbent. The amount of the composite adsorbent added was 5% of the total mass of the filtered solution. The mixture was stirred at a temperature of 30°C and a stirring speed of 170 r / min for 38 minutes. During the stirring process, a slight bubbling stirring was performed by bottom air intake to ensure full contact between the adsorbent and the solution. After the stirring was completed, a tylosin pretreatment solution was obtained. The tylosin pretreatment liquid is transferred to a reaction tank, and a composite microbial flora is added, including tylosin efficient degradation bacteria, nitrogen-fixing bacteria and phosphate-solubilizing bacteria, and the composition thereof is 5:3:2. The temperature in the reaction tank is adjusted to 33°C, the pH value is adjusted to 7.0, the dissolved oxygen is controlled at 5 mg / L, and a 44-hour aerobic fermentation treatment is performed. At the same time, an ultrasonic device is turned on, and its frequency is set to 28 kHz and the power is set to 200 W. The liquid in the reaction tank is subjected to intermittent ultrasonic treatment, and the ultrasonic treatment is performed for 8 minutes and then stopped for 4 minutes. After the ultrasonic treatment is completed, a tylosin fermentation liquid is obtained, which is stored for later use; According to the weight of potassium nitrate 15g, diammonium phosphate 8.5g, ferrous sulfate 3.8g, boric acid 0.18g, sodium molybdate 0.09g and zinc sulfate 0.048g per liter of tylosin fermentation liquid, slowly add them into the tylosin fermentation liquid at 34°C, turn on the stirring device at the same time, stir at a stirring speed of 210r / min for 23min, add biologically active substances after stirring, the biologically active substances are prepared by copolymerization of N-isopropylacrylamide and acrylic acid, and in the preparation process, N-isopropylacrylamide and acrylic acid are reacted under nitrogen protection. Acrylic acid and a cross-linking agent N,N'-methylenebisacrylamide are dissolved in deionized water in a mass ratio of 7:3:0.5, an initiator ammonium persulfate and a promoter tetramethylethylenediamine are added, and the mixture is reacted at a temperature of 30°C for 4 hours to prepare a hydrogel, in which metabolites extracted from a special halophilic archaea fermentation broth are encapsulated, and the encapsulation rate is 60%. The amount of microbial metabolites encapsulated in the hydrogel is 4.5% of the mass of the tylosin fermentation broth, and the mixture is stirred at a temperature of 32°C and a stirring speed of 230 r / min for 15 minutes to prepare a liquid fertilizer semi-finished product; The semi-finished liquid fertilizer was placed in a reaction vessel with constant temperature and ultrasonic synergistic functions, and a biochar composite thickener was added. The biochar composite thickener was made of bamboo charcoal treated with high temperature activation (700°C) and nano-montmorillonite in a mass ratio of 1:1. The biochar composite thickener was then fully mixed and refined to an average particle size of 80 nm by ball milling. The amount of biochar added was 5% of the total mass of the semi-finished liquid fertilizer. The mixture was stirred at a temperature of 40°C and a stirring rate of 300 r / min for 10 minutes. After the stirring was completed, the ultrasonic device was turned on for 5 minutes, and the ultrasonic frequency was set to 40 kHz and the ultrasonic power was set to 15. 0W, after the ultrasonic treatment is completed, a polysaccharide emulsifier is added thereto, and the added amount is 3.5% of the total mass of the liquid fertilizer semi-finished product. Under the temperature condition of 50°C, a high-speed shear emulsifier is used to shear and emulsify at a speed of 4800r / min for 9.5min to form a uniform and stable emulsified system. After the emulsification is completed, an antioxidant is added, and the added amount is 0.12% of the total mass of the liquid fertilizer semi-finished product. After the addition is completed, the liquid fertilizer semi-finished product is stirred at a temperature condition of 38°C and a stirring speed of 290r / min for 10min to evenly distribute the antioxidant in the liquid fertilizer system to obtain a liquid fertilizer product.

[0031] Quality inspection steps, Tylosin residue detection: Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS / MS) technology was used to accurately determine the residual amount of tylosin. The liquid fertilizer product was diluted with a mixed solution of acetonitrile-water (1:1, v / v) at a dilution ratio of 1:1000, filtered through a 0.22um filter membrane, and then injected into the UPLC-MS / MS system. The chromatographic column was C 18Reversed phase column (2.1 mm × 100 mm, 1.7 um), mobile phase A was 0.1% formic acid in water, mobile phase B was acetonitrile, and gradient elution program was used: 0 min-2 min, 5%-20% B; 2min-8min, 20%-50%B; 8min-12min, 50%-95%B; 12min-15min, 95%B; The flow rate was set at 0.3 mL / min, the column temperature was maintained at 40 °C, and the mass spectrometer used an electrospray ion source (ESI), positive ion mode scanning, and multiple reaction monitoring (MRM) mode to detect the characteristic ion pairs of tylosin and its degradation products. The test results showed that the residual amount of tylosin was 0.003 mg / kg; Heavy metal content detection: The heavy metal content was detected by inductively coupled plasma mass spectrometry (ICP-MS). 5 mL of liquid fertilizer was added with 1 mL of nitric acid and digested in a microwave digester. The digestion procedure was as follows: Keep at 120℃ for 5min, 150℃ for 10min, and 180℃ for 15min. After cooling, adjust the volume to 50mL. Introduce the digested solution into ICP-MS for detection. Use indium (In) and bismuth (Bi) as internal standard elements to correct matrix effect and signal drift. The detection results are: lead (Pb) content 0.01mg / L, cadmium (Cd) content 0.005mg / L, mercury (Hg) content not detected, arsenic (As) content 0.008mg / L. Nutrient content testing, The liquid fertilizer product was scanned and analyzed using a full spectrum analyzer to detect its absorption spectrum characteristics in the ultraviolet-visible-near infrared band. The nutrient content range and abnormal substance interference were preliminarily determined based on the changes in the absorption peaks at specific wavelengths. The main nutrient content was further determined using conventional chemical analysis methods: The nitrogen content is 12.5g / L (in the form of potassium nitrate and ammonia nitrogen, etc.), the phosphorus content is 4.2g / L (in the form of diammonium phosphate), the potassium content is 6.8g / L (in the form of potassium nitrate), the iron content is 0.28g / L (in the form of ferrous sulfate), the boron content is 0.035g / L (in the form of boric acid), the molybdenum content is 0.018g / L (in the form of sodium molybdate) and the zinc content is 0.009g / L (in the form of zinc sulfate); pH value detection, The pH value of the liquid fertilizer product was measured using a precision pH meter. After the pH meter electrode was calibrated with a standard buffer solution (pH=4.01, 6.86, 9.18), it was inserted into the liquid fertilizer product. After the reading stabilized, the pH value was recorded as 6.98, and the measurement error was controlled within ±0.02. The liquid fertilizer product prepared by the above embodiment met the relevant requirements in all indicators, could effectively improve soil fertility, and had good stability and safety, and was suitable for soil improvement and crop fertilization in agricultural production.

[0032] Test the finished liquid of tylosin. Purpose of the test: Evaluate the effect of liquid fertilizer produced from tylosin finished liquid on improving soil fertility and its impact on crop growth, and verify the feasibility and effectiveness of the liquid fertilizer in agricultural applications; Select loam with medium fertility and uniform texture, whose basic physical and chemical properties are: organic matter content 2.5%, total nitrogen 0.15%, available phosphorus 15mg / kg, quick-acting potassium 80mg / kg, pH value 7.2, select common vegetable crops lettuce as the test object, and produce liquid fertilizer according to the preparation method of producing liquid fertilizer with the above-mentioned tylosin finished liquid; Three treatment groups were set up, each with 3 replicates, for a total of 9 experimental plots, each with an area of ​​10 m²; Treatment 1: blank control group, only the same amount of water was used for irrigation, and no fertilizer was applied; Treatment 2: The conventional fertilizer control group was treated with commercially available conventional compound fertilizer (nitrogen-phosphorus-potassium ratio of 15-15-15) at the recommended dosage of 50 kg / mu; Treatment 3: Tylosin liquid fertilizer test group, the liquid fertilizer product prepared by the present invention was applied at a dosage of 100 L / mu; The test soil was plowed 30cm deep, the soil clods were broken, and the land was leveled to make the soil loose and breathable. The test plots were divided according to the test design, and a 50cm isolation zone was set between the plots to prevent the fertilizers from penetrating each other and affecting the test results. One day before sowing, each treatment plot was fertilized according to the test design. Treatment 1 was only irrigated with an equal amount of water. Treatment 2 was evenly spread on the soil surface and then shallowly turned into the soil 10cm. Treatment 3 diluted the liquid fertilizer product 100 times and evenly sprayed it on the soil surface through the sprinkler irrigation system. On the second day after fertilization, lettuce seeds were sown in each plot, with a sowing amount of 2g / m² and a sowing depth of 1cm, and then covered with a thin layer of soil and lightly compacted. Water management: According to the soil moisture conditions, the soil moisture content is maintained between 60% and 80%. The drip irrigation system is used for irrigation. The amount of irrigation each time is adjusted according to the weather and soil moisture to ensure consistent water supply in each treatment area. Pest and disease control: During the test period, closely observe the growth of lettuce. If pests and diseases occur, use biological control methods to prevent and control them, and avoid using chemical pesticides to interfere with the test results; Germination rate determination: 5 days after sowing, the number of lettuce seeds germinated in each treatment plot was counted and the germination rate was calculated, germination rate (%) = (number of germinated seeds / number of sown seeds) × 100; Determination of seedling growth indicators: 15 days after sowing, 10 lettuce seedlings were randomly selected from each plot to measure their plant height (the height from the stem base to the growth point), stem diameter (the diameter 1 cm from the stem base), number of leaves and leaf area. The leaf area was measured using a leaf area meter. Biomass determination: After 30 days of growth, the lettuce plants in each treatment area were harvested, and the fresh weight and dry weight of the aboveground part were determined. The harvested lettuce plants were sterilized in an oven at 105°C for 30 min, and then dried at 80°C to constant weight, and the dry weight was obtained by weighing.

[0033] After the lettuce was harvested, soil samples were collected from each treatment plot at a depth of 0 cm to 20 cm. Five points were collected from each plot, mixed evenly, and brought back to the laboratory for analysis to determine soil fertility indicators such as soil organic matter content, total nitrogen, available phosphorus, available potassium, and pH value. The determination method was based on relevant national standards. Germination rate, Treatment 1 (blank control): germination rate 75%; Treatment 2 (conventional fertilizer): germination rate was 82%; Treatment 3 (Tylosin liquid fertilizer): germination rate was 88% Seedling growth index (15 days after sowing) and biomass (30 days after growth) data are as follows: Figure 2 The soil fertility index data are shown in the attached Figure 3 As shown; In terms of germination rate, the germination rate of the group treated with tylosin liquid fertilizer was the highest, which was 13 percentage points higher than that of the blank control group and 6 percentage points higher than that of the traditional fertilizer control group. This indicates that the nutrients and bioactive substances contained in the liquid fertilizer may promote seed germination and improve seed vitality and germination uniformity. In the seedling growth stage, the plant height, stem diameter, number of leaves and leaf area of ​​the tylosin liquid fertilizer treatment group were significantly higher than those of the blank control group and the traditional fertilizer control group. The plant height increased by 2.6 cm and 1.3 cm compared with the blank control group, the stem diameter increased by 0.7 mm and 0.3 mm compared with the traditional fertilizer control group, the number of leaves increased by 2 and 0.7 compared with the blank control group, and the leaf area increased by 14.3 cm² and 7.2 cm² compared with the traditional fertilizer control group. These results indicate that the liquid fertilizer can provide sufficient nutrients and a good growth environment for seedling growth, and promote the growth of stems and leaves and photosynthesis of seedlings. In terms of biomass, the fresh weight and dry weight of the aboveground part of the group treated with tylosin liquid fertilizer were significantly higher than those of the other two groups. The fresh weight increased by 330g / m² compared with the blank control group and 160g / m² compared with the traditional fertilizer control group. The dry weight increased by 37g / m² compared with the blank control group and 17g / m² compared with the traditional fertilizer control group. This shows that the liquid fertilizer can promote the growth and material accumulation of lettuce plants, and improve the yield and quality of lettuce. The content of soil organic matter increased after the treatment with tylosin liquid fertilizer, which was 0.7 percentage points higher than that of the blank control group and 0.4 percentage points higher than that of the traditional fertilizer control group. This may be because the organic components and microbial metabolites in the liquid fertilizer accumulated in the soil, promoting the formation and transformation of soil organic matter. The total nitrogen, available phosphorus and quick-acting potassium contents in the tylosin liquid fertilizer treatment group were significantly higher than those in the other two groups. The total nitrogen content was 0.06 percentage points higher than that in the blank control group and 0.03 percentage points higher than that in the traditional fertilizer control group. The effective phosphorus content was 16 mg / kg higher than that in the blank control group and 8 mg / kg higher than that in the traditional fertilizer control group. The quick-acting potassium content was 40 mg / kg higher than that in the blank control group and 20 mg / kg higher than that in the traditional fertilizer control group. This indicates that the liquid fertilizer can effectively supplement nitrogen, phosphorus, potassium and other nutrients in the soil and improve the soil's fertility supply capacity. The pH value decreased slightly after the treatment with tylosin liquid fertilizer, but it was still within the range suitable for crop growth. This may be because the acidic components in the liquid fertilizer or the acidic substances produced by microbial metabolism neutralized the alkalinity of the soil to a certain extent, making the soil pH value tend to be neutral, which is conducive to the absorption and utilization of nutrients by crops. Through the above experiments, it can be concluded that the liquid fertilizer produced by tylosin finished liquid has a significant effect on improving soil fertility and promoting the growth of lettuce. Compared with the blank control group and the traditional fertilizer control group, the liquid fertilizer can improve the germination rate, seedling growth index and biomass of lettuce, while increasing the organic matter, total nitrogen, available phosphorus and quick-acting potassium content of the soil, and improving the physical and chemical properties of the soil. This shows that the liquid fertilizer product has a significant improvement in improving soil fertility, and at the same time proves the feasibility of using tylosin finished liquid to produce liquid fertilizer to improve soil fertility.

[0034] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.

[0035] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0036] The above contents are merely examples and explanations of the present invention. Various modifications or additions to the specific embodiments described or replacements in similar ways by technicians in the technical field shall fall within the protection scope of the present invention as long as they do not deviate from the invention or exceed the scope defined by the claims.

[0037] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing liquid fertilizer from tylosin finished liquid to improve soil fertility, comprising pretreatment of tylosin finished liquid, directional degradation of finished liquid, nutrient blending and stabilization of finished fertilizer, characterized in that: The specific operation steps of the preparation method of the tylosin finished liquid to produce liquid fertilizer to improve soil fertility are as follows: Step 1, collecting the tylosin finished product liquid, adding water to dilute it and filtering it, and adding an adsorbent to it after filtering to prepare a tylosin pretreatment liquid; Step 2: transferring the tylosin pretreatment liquid to a reaction tank, adding microbial flora for fermentation treatment, and simultaneously turning on an ultrasonic device for ultrasonic-assisted enhancement to obtain a tylosin fermentation liquid; Step 3, adding nutrients and trace elements to the tylosin fermentation liquid and mixing, and then adding biologically active substances according to the ratio to obtain a semi-finished liquid fertilizer; Step 4: Put the semi-finished liquid fertilizer into a reaction container, add a thickener and an emulsifier for stabilization, and add an antioxidant to mix to form a finished liquid fertilizer; Step 5: Take the finished liquid fertilizer for quality testing, including tylosin residue, heavy metal content, nutrient content and pH value.

2. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step 1, the tylosin finished liquid is collected, diluted according to a volume ratio of tylosin to water of 1:200-300, stirred at a temperature of 30°C at a stirring speed of 150r / min-180r / min for 20min-25min, and after the stirring and dilution is completed, it is filtered through a ceramic membrane filter with a pore size of 100um to remove large particle impurities. After the filtration is completed, a composite adsorbent is added thereto, and the amount of the composite adsorbent added is 4%-6% of the total mass of the filtered solution. At a temperature of 30°C, it is stirred at a stirring speed of 160r / min-180r / min for 30min-45min, and after the stirring is completed, a tylosin pretreatment liquid is obtained.

3. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step 1, the adsorbent is prepared by mixing specially treated graphene and mesoporous molecular sieve in a mass ratio of 3:2, the special treatment is to use a mixed solution of concentrated nitric acid and concentrated sulfuric acid to treat it at a temperature of 80°C for 3h-4h, and after the treatment, it is rinsed with deionized water to neutrality, and after the rinsing, it is refluxed with octadecyltriethoxysilane in a toluene solution for 6h to obtain specially treated graphene, which is mixed with the mesoporous molecular sieve to prepare a composite adsorbent.

4. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step 2, the tylosin pretreatment liquid is transferred to a reaction tank, and a composite microbial flora is added, including tylosin efficient degradation bacteria, nitrogen-fixing bacteria and phosphate-solubilizing bacteria, which are composed in a ratio of 5:3:

2. The composite microbial flora breaks down the tylosin molecules into small molecular organic acids and amino acids, and the nitrogen fixation reaction formula is: ； In the above reaction, nitrogen in the air is converted into ammonia nitrogen after being treated by nitrogen-fixing bacteria.

5. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step 2, the composite microbial flora is transferred into a reaction tank, the temperature in the reaction tank is adjusted to 32° C.-35° C., the pH value is adjusted to 6.8-7.2, the dissolved oxygen is controlled at 4 mg / L-6 mg / L, and aerobic fermentation treatment is performed for 40 h-48 h. At the same time, an ultrasonic device is turned on, the frequency is set to 25 kHz-30 kHz, and the power is set to 180 W-220 W. The liquid in the reaction tank is intermittently ultrasonicated, and the ultrasonic treatment is performed for 8 min and 4 min respectively. After the ultrasonic treatment is completed, a tylosin fermentation liquid is obtained and stored for later use.

6. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step 3, 14g-16g potassium nitrate, 8g-9g diammonium phosphate, 3.5g-4g ferrous sulfate, 0.15g-0.2g boric acid, 0.08g-0.1g sodium molybdate and 0.045g-0.05g zinc sulfate are weighed per liter of tylosin fermentation liquid, and the mixture is slowly added to the tylosin fermentation liquid under an environmental condition of 33°C-35°C, and a stirring device is turned on at the same time, and the mixture is stirred at a stirring speed of 200r / min-220r / min for 20min-25min. After the stirring is completed, the biologically active substance is added, and the mixture is stirred at a stirring speed of 230r / min for 15min under a temperature condition of 30°C-35°C to obtain a liquid fertilizer semi-finished product.

7. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step three, the bioactive substance is prepared by copolymerization of N-isopropylacrylamide and acrylic acid. During the preparation process, under nitrogen protection, N-isopropylacrylamide, acrylic acid and cross-linking agent N,N'-methylenebisacrylamide are dissolved in deionized water at a mass ratio of 7:3:0.5, initiator ammonium persulfate and promoter tetramethylethylenediamine are added, and the reaction is carried out at a temperature of 30°C for 4 hours to prepare a hydrogel, in which metabolites extracted from a special halophilic archaea fermentation broth are encapsulated, and the encapsulation rate is 60%. The amount of microbial metabolites encapsulated by the hydrogel is 4.5% of the mass of the tylosin fermentation broth, in a soil environment.

8. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step 4, the liquid fertilizer semi-finished product is transferred into a reaction container with constant temperature and ultrasonic synergistic functions, and a biochar composite thickener is added in an amount of 4%-6% of the total mass of the liquid fertilizer semi-finished product. The mixture is stirred at a stirring rate of 300 r / min for 10 minutes at a temperature of 40° C. After the stirring is completed, an ultrasonic device is turned on for 5 minutes, and the ultrasonic frequency is set to 40 kHz and the ultrasonic power is set to 150 W. After the ultrasonic treatment is completed, a polysaccharide emulsifier is added thereto in an amount of 3%-4% of the total mass of the liquid fertilizer semi-finished product. At a temperature of 50°C, a high-speed shear emulsifier is used to shear and emulsify at a speed of 4800r / min for 9min-10min to form a uniform and stable emulsified system. After the emulsification is completed, an antioxidant is added in an amount of 0.09%-0.15% of the total mass of the liquid fertilizer semi-finished product. After the addition is completed, the liquid fertilizer semi-finished product is stirred at a temperature of 35°C-40°C and a stirring speed of 280r / min-300r / min for 10min to evenly distribute the antioxidant in the liquid fertilizer system to obtain a liquid fertilizer product.

9. The method for preparing a tylosin finished liquid to produce liquid fertilizer to improve soil fertility according to claim 1, characterized in that: In the step 5, a full spectrum analyzer is used to scan and analyze the finished liquid fertilizer product, and its absorption spectrum characteristics in the ultraviolet-visible light-near infrared band are detected. The nutrient content range and abnormal substance interference are preliminarily judged according to the change of the absorption peak at a specific wavelength. The ultra-high performance liquid chromatography-tandem mass spectrometry technology is used to accurately determine the tylosin residue, the inductively coupled plasma mass spectrometry is used to detect the heavy metal content, and the precision pH meter is used to determine the pH value of the finished liquid fertilizer product, and the measurement error is controlled within ±0.02.

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