A method for preparing fertilizer from histidine fermentation waste liquid

Abstract

The invention discloses a method for preparing fertilizer from histidine fermentation waste liquid, and the invention relates to the technical field of fertilizer preparation, including pretreatment of histidine fermentation waste liquid, extraction treatment, electrolysis of fermentation waste liquid, nutrient addition and quality detection. The invention has the advantages that: through comprehensive treatment of histidine fermentation waste liquid, waste liquid that may be directly discharged to cause environmental pollution and waste of resources is converted into valuable fertilizer, impurities are removed, useful components are extracted, and effective recycling of resources is achieved, while potential pollution to the environment is reduced, which is in line with the development direction of efficient resource utilization and reduction of environmental pollution. By using natural acid-base regulators, equipment made of corrosion-resistant materials, environmentally friendly extraction and treatment technology, and supercritical fluid extraction technology, the use of traditional organic solvents is avoided, secondary pollution to the environment is reduced, and the addition of natural stabilizers also meets environmental protection requirements.

Description

Technical Field

[0001] The invention relates to the technical field of fertilizer preparation, in particular to a method for preparing fertilizer from histidine fermentation waste liquid. Background Art

[0002] In today's biotechnology and agricultural fields, efficient use of resources and reduction of environmental pollution have become key development directions. Histidine, as an important amino acid, is widely used in many industries such as medicine, food, and feed. In the production process of histidine, fermentation technology is widely used, which produces a large amount of histidine fermentation waste liquid; At present, histidine fermentation wastewater usually faces treatment difficulties after histidine is extracted. On the one hand, direct discharge of histidine fermentation wastewater will cause serious environmental pollution, which may contain underutilized organic matter, trace elements and residual fermentation substrates. If these substances enter the water or soil, they will destroy the ecological balance and affect the sustainable development of the surrounding ecological environment. On the other hand, simple treatment and discharge are also difficult to achieve effective utilization of resources, resulting in a huge waste of resources. In agricultural production, the demand for fertilizers continues to grow. Although traditional chemical fertilizers can provide the necessary nutrients for crops in the short term, long-term use will lead to many problems such as soil compaction, decreased fertility, and environmental pollution. In contrast, organic fertilizers have significant advantages such as improving soil structure, increasing soil fertility, promoting crop growth, and being environmentally friendly, so they are becoming more and more popular. Existing fertilizer preparation methods have shortcomings in treating histidine fermentation waste liquid. First, there is a lack of treatment steps specifically targeting the characteristics of histidine fermentation waste liquid, and the effective nutrients therein cannot be fully extracted. For example, the organic matter and trace elements in the histidine fermentation waste liquid may not be reasonably separated and utilized, resulting in a low nutrient content of the fertilizer. Secondly, the existing preparation process may have problems of complex process and high cost, which is not conducive to large-scale promotion and application. Furthermore, in the process of preparing fertilizer, the quality and stability of the fertilizer may not be effectively controlled, making it difficult to ensure the fertilizer effect of the fertilizer. For this reason, we propose a method for preparing fertilizer from histidine fermentation waste liquid. Summary of the invention

[0003] The object of the present invention is to provide a method for preparing fertilizer from histidine fermentation waste 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 fertilizer from histidine fermentation waste liquid, comprising pretreatment of histidine fermentation waste liquid, extraction treatment, electrolysis of fermentation waste liquid, addition of nutrients and quality detection, and the specific operation steps of preparing fertilizer from histidine fermentation waste liquid are as follows: Step 1: collecting the histidine fermentation waste liquid, filtering it using two sets of micro-nano filtration membranes, performing backwashing operations regularly during the filtration process, and transferring it to a magnetic filtration device for adsorption separation after filtration, and obtaining a histidine fermentation liquid after completion; Step 2: Transfer the histidine fermentation liquid into a corrosion-resistant container, use supercritical fluid extraction technology, use CO2 as a supercritical fluid, extract the active ingredients in the histidine fermentation waste liquid, store it in a glass storage container, and place it in a cool and dry environment for standby use; Step 3: adding the extracted active ingredients, polysaccharide complexes, bioactive enzyme preparations, alkaloid extracts and histidine fermentation broth into a multi-stage corrosion-resistant reactor, mixing the substances in stages, and electrolyzing the histidine fermentation broth after mixing to obtain an electrolytic fermentation broth; Step 4: transferring the electrolytic fermentation liquid into a corrosion-resistant container, adding insect protein extract, marine biogenic polysaccharide, microbial metabolite complex and trace elements, stirring and mixing, and using a microwave device for microwave-assisted treatment. After completion, adding a natural stabilizer, stirring and mixing to obtain a liquid fertilizer; Step 5: Sample the prepared liquid fertilizer and conduct a quality inspection on it. If it passes the inspection, it will be filled in a sterile environment and stored in a dry and ventilated environment.

[0005] As a further scheme of the present invention: in the step 1, the pH value of the collected histidine fermentation waste liquid is adjusted, and a natural acid-base regulator is added to adjust the pH value of the histidine fermentation waste liquid to 6.5-7.5. After the adjustment is completed, the histidine fermentation waste liquid is filtered using a micro-nano filtration membrane. The filtration device uses a two-layer filtration structure, the pore size of the first layer of the filtration membrane is 0.1um, and the pore size of the second layer of the filtration membrane is 0.05um. During the multi-group filtration process, the filtration pressure is controlled to be 0.2MPa-0.25MPa, the filtration temperature is 30°C, and the filtration flow rate is 3L / min-4L / min. At the same time, backwashing operation is performed regularly during the filtration process, the backwashing frequency is once per hour, and the backwashing pressure is 1.5 times the filtration pressure.

[0006] As a further solution of the present invention: in the step 1, after the filtration is completed, it is transferred to a magnetic filtration device for adsorption separation, and the filtered fermentation liquid is introduced into the inlet of the magnetic filtration device through a corrosion-resistant pipe, the inner diameter of the pipe is 50 mm, and the flow rate is controlled at 2 L / min. After the fermentation liquid enters the magnetic filtration device, it first passes through a preliminary magnetic field area to preliminarily magnetize the metal ions and magnetic particles in the histidine fermentation waste liquid, and the fermentation liquid enters the main adsorption area, and the metal ions and magnetic particles are adsorbed onto the nanofiber filter medium by the strong magnetic field. After the histidine fermentation waste liquid is treated by magnetic filtration, it flows out from the outlet of the magnetic filtration device to obtain histidine fermentation liquid.

[0007] As a further scheme of the present invention: in the step 2, the histidine fermentation broth is transferred into a corrosion-resistant container, the temperature is adjusted to 40°C-50°C, the pressure is set to 12MPa, the flow rate of CO2 is controlled to 5L / min-8L / min, and the extraction time is set to 3h-4h. During the extraction process, the histidine fermentation broth is slowly stirred using a stirring device at a stirring rate of 30r / min-40r / min. After the extraction is completed, the supercritical CO2 fluid containing the active ingredient enters the separation device through a specific pipeline, the temperature of the separation device is adjusted to 35°C, the pressure is reduced to 6MPa, CO2 is converted from a supercritical state to a gaseous state, and the active ingredient is collected in a glass storage container, placed in a cool and dry environment, the temperature is controlled at 20°C-25°C, and stored for later use.

[0008] As a further solution of the present invention: in the step 3, a specially made multi-stage corrosion-resistant reactor is selected, the reactor is divided into three independent reaction areas, each area can independently control the temperature, pressure and stirring speed, the histidine fermentation liquid is added to the first-stage reaction area in the reactor, the amount of the histidine fermentation liquid added is controlled to be 40%-50% of the total volume of the reactor, and then the extracted active ingredients are slowly added to the histidine fermentation liquid, the amount of the active ingredients added is 10%-15% of the total weight of the histidine fermentation liquid, and then the polysaccharide complex, the biologically active enzyme preparation and the alkaloid extract are added, and the addition amounts are 5%-8%, 3%-5% and 3%-4% of the total weight of the histidine fermentation liquid, respectively, and they are stirred and mixed to obtain a mixed fermentation liquid.

[0009] As a further solution of the present invention: in step 3, electrode plates are respectively installed in the three reaction areas in the reactor, and after the histidine is mixed with the material components, the electrolysis voltage in the reaction area is controlled to be 30V-40V and the current density is 5A / dm 2 -8A / dm 2 The electrolysis time is controlled between 2h-3h. During the electrolysis process, the circulating cooling system of the reactor is used to control the reaction temperature at 35℃-40℃. Deionized water is selected as the circulating cooling medium with a flow rate of 15L / min. During the electrolysis treatment, stirring operation is performed simultaneously. The stirring speed of the first-stage reaction area is 40r / min-50r / min, which is mainly used for preliminary mixing and reaction to fully mix the histidine fermentation broth and the active ingredients. The stirring speed of the second-stage reaction area is 30r / min-40r / min, which is mainly used for the interaction between the polysaccharide complex, the bioactive enzyme preparation and the alkaloid extract and the histidine fermentation broth. The stirring speed of the third-stage reaction area is 20r / min-30r / min, which is mainly used for adjustment and stabilization after mixing. After the treatment is completed, the electrolytic fermentation broth is obtained.

[0010] As a further scheme of the present invention: in the step 4, insect protein extract, marine biosource polysaccharide and microbial metabolite complex are selected as nutrient additives, and the added amounts thereof are 8%-12%, 5%-7% and 4%-8% of the total weight of the electrolytic fermentation broth, respectively; trace elements are iron, zinc, copper and manganese, and the trace elements are added in the form of organic chelates, and the added amounts thereof are 0.3%-0.5%, 0.07%-0.2%, 0.08%-0.1% and 0.05%-0.02% of the total weight of the electrolytic fermentation broth, and the nutrient additives and trace elements are slowly added to the electrolytic fermentation broth in sequence, and stirred at a stirring rate of 30 r / min.

[0011] As a further solution of the present invention: in the step 4, after the stirring is completed, the mixed liquid is treated with a microwave device, the microwave frequency is set to 2450MHz, the power is 800W-1200W, and the treatment is 20min-30min. During the treatment process, circulating water cooling is used to control the liquid temperature at 35℃-40℃. After the microwave-assisted treatment is completed, a mixed solution is obtained, and a natural stabilizer is added and mixed in an amount of 2%-4% of the total weight of the mixed solution. Stirring is continued for 15min to fully mix the natural stabilizer and the mixed solution to obtain a liquid fertilizer.

[0012] As a further solution of the present invention: In the step 5, 5-8 samples need to be taken for testing for each batch of liquid fertilizer produced. After the liquid fertilizer is prepared, samples are taken from the top, middle and bottom of the storage container for testing. The nutrient component testing includes the testing of nitrogen, phosphorus, potassium and trace elements, and stability and safety testing are performed at the same time.

[0013] By adopting the above technical solution, compared with the prior art, the beneficial effects of the present invention are: 1. The present invention converts the waste liquid that may be directly discharged to cause environmental pollution and waste of resources into valuable fertilizer by comprehensively treating the waste liquid of histidine fermentation, removes impurities, extracts useful components, realizes effective recycling of resources, and reduces potential pollution to the environment, which is in line with the development direction of efficient utilization of resources and reduction of environmental pollution. By using natural acid-base regulators, equipment made of corrosion-resistant materials, and environmentally friendly extraction and treatment technology, and supercritical fluid extraction technology, the use of traditional organic solvents is avoided, and secondary pollution to the environment is reduced. The addition of natural stabilizers also meets environmental protection requirements and reduces potential harm to the ecological environment. In addition, each link in the production process focuses on reducing the emission of pollutants and the consumption of resources. The backwashing operation design in the filtration process not only ensures the filtration effect, but also increases the service life of the filtration membrane, and reduces the generation of waste. By coordinating the process steps, efficient treatment of histidine fermentation waste liquid and high-quality preparation of fertilizers are achieved. This integrated and innovative process model provides new ideas and methods for the resource utilization of other similar wastes. 2. The present invention adds a variety of special ingredients such as insect protein extracts, marine biosource polysaccharides and microbial metabolite complexes to liquid fertilizers, and also reasonably matches trace elements such as iron, zinc, copper, and manganese. These ingredients work together to help promote plant growth and development, regulate soil microbial communities, and promote root growth, making the fertilizer more nutritious and balanced, and better meeting the needs of crops at different growth stages, providing comprehensive nutritional support for crops. The multi-stage reactor is used to mix the histidine fermentation broth, which is conducive to better interaction between polysaccharide complexes, bioactive enzyme preparations, etc. and the fermentation broth, and promotes complex reactions such as decomposition and conversion of organic matter. At the same time, the third-stage reactor is used for mixing, and the histidine fermentation broth can be adjusted and stabilized after mixing, avoiding excessive stirring to damage the already formed system, thereby ensuring the smooth progress of the entire reaction process and the stability of product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The figure is a schematic diagram of the process of preparing fertilizer from histidine fermentation waste liquid in an embodiment of the present invention. DETAILED DESCRIPTION

[0015] 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.

[0016] The present invention provides a method for preparing fertilizer from histidine fermentation waste liquid, comprising pretreatment of the histidine fermentation waste liquid, extraction treatment, electrolysis of the fermentation waste liquid, addition of nutrients and quality testing. The specific operation steps of preparing fertilizer from the histidine fermentation waste liquid are as follows: Step 1: collecting the histidine fermentation waste liquid, filtering it using two sets of micro-nano filtration membranes, performing backwashing operations regularly during the filtration process, and transferring it to a magnetic filtration device for adsorption separation after filtration, and obtaining a histidine fermentation liquid after completion; Step 2: Transfer the histidine fermentation liquid into a corrosion-resistant container, use supercritical fluid extraction technology, use CO2 as a supercritical fluid, extract the active ingredients in the histidine fermentation waste liquid, store it in a glass storage container, and place it in a cool and dry environment for standby use; Step 3: adding the extracted active ingredients, polysaccharide complexes, bioactive enzyme preparations, alkaloid extracts and histidine fermentation broth into a multi-stage corrosion-resistant reactor, mixing the substances in stages, and electrolyzing the histidine fermentation broth after mixing to obtain an electrolytic fermentation broth; Step 4: transferring the electrolytic fermentation liquid into a corrosion-resistant container, adding insect protein extract, marine biogenic polysaccharide, microbial metabolite complex and trace elements, stirring and mixing, and using a microwave device for microwave-assisted treatment. After completion, adding a natural stabilizer, stirring and mixing to obtain a liquid fertilizer; Step 5: Sample the prepared liquid fertilizer and conduct a quality inspection on it. If it passes the inspection, it will be filled in a sterile environment and stored in a dry and ventilated environment.

[0017] In one embodiment of the present invention: in step 1, the pH value of the collected histidine fermentation waste liquid is adjusted, and a natural acid-base regulator is added to adjust the pH value of the histidine fermentation waste liquid to 6.5-7.5. After the adjustment is completed, the histidine fermentation waste liquid is filtered using a micro-nano filtration membrane. The filtration device uses a two-layer filtration structure, the pore size of the first layer of the filter membrane is 0.1um, and the pore size of the second layer of the filter membrane is 0.05um. During the multi-group filtration process, the filtration pressure is controlled to be 0.2MPa-0.25MPa, the filtration temperature is 30°C, and the filtration flow rate is 3L / min-4L / min. At the same time, backwashing operation is performed regularly during the filtration process, the backwashing frequency is once per hour, and the backwashing pressure is 1.5 times the filtration pressure.

[0018] In one embodiment of the present invention: in step 1, after the filtration is completed, it is transferred to a magnetic filtration device for adsorption separation, and the filtered fermentation liquid is introduced into the inlet of the magnetic filtration device through a corrosion-resistant pipe, the inner diameter of the pipe is 50 mm, and the flow rate is controlled at 2 L / min. After the fermentation liquid enters the magnetic filtration device, it first passes through a preliminary magnetic field area to preliminarily magnetize the metal ions and magnetic particles in the histidine fermentation waste liquid, and the fermentation liquid enters the main adsorption area, and the metal ions and magnetic particles are adsorbed onto the nanofiber filter medium by the strong magnetic field. After the histidine fermentation waste liquid is treated by magnetic filtration, it flows out from the outlet of the magnetic filtration device to obtain a histidine fermentation liquid.

[0019] In one embodiment of the present invention: in step 2, the histidine fermentation broth is transferred to a corrosion-resistant container, the temperature is adjusted to 40°C-50°C, the pressure is set to 12MPa, the flow rate of CO2 is controlled to 5L / min-8L / min, and the extraction time is set to 3h-4h. During the extraction process, the histidine fermentation broth is slowly stirred using a stirring device at a stirring rate of 30r / min-40r / min. After the extraction is completed, the supercritical CO2 fluid containing the active ingredient enters the separation device through a specific pipeline, the temperature of the separation device is adjusted to 35°C, the pressure is reduced to 6MPa, CO2 is converted from a supercritical state to a gaseous state, and the active ingredient is collected in a glass storage container, placed in a cool and dry environment, the temperature is controlled at 20°C-25°C, and stored for later use.

[0020] In one embodiment of the present invention: in step three, a special multi-stage corrosion-resistant reactor is selected, the reactor is divided into three independent reaction areas, each area can independently control the temperature, pressure and stirring speed, the histidine fermentation liquid is added to the first-stage reaction area in the reactor, the amount of the histidine fermentation liquid added is controlled to be 40%-50% of the total volume of the reactor, and then the extracted active ingredients are slowly added to the histidine fermentation liquid, the amount of the active ingredients added is 10%-15% of the total weight of the histidine fermentation liquid, and then the polysaccharide complex, the biologically active enzyme preparation and the alkaloid extract are added, and the addition amounts are 5%-8%, 3%-5% and 3%-4% of the total weight of the histidine fermentation liquid, respectively, and they are stirred and mixed to obtain a mixed fermentation liquid.

[0021] In one embodiment of the present invention, in step 3, electrode plates are installed in the three reaction areas of the reactor, and after the histidine is mixed with the material components, the electrolysis voltage in the reaction area is controlled to be 30V-40V and the current density is 5A / dm 2 -8A / dm 2The electrolysis time is controlled between 2h-3h. During the electrolysis process, the circulating cooling system of the reactor is used to control the reaction temperature at 35℃-40℃. Deionized water is selected as the circulating cooling medium with a flow rate of 15L / min. During the electrolysis treatment, stirring operation is performed simultaneously. The stirring speed of the first-stage reaction area is 40r / min-50r / min, which is mainly used for preliminary mixing and reaction to fully mix the histidine fermentation broth and the active ingredients. The stirring speed of the second-stage reaction area is 30r / min-40r / min, which is mainly used for the interaction between the polysaccharide complex, the bioactive enzyme preparation and the alkaloid extract and the histidine fermentation broth. The stirring speed of the third-stage reaction area is 20r / min-30r / min, which is mainly used for adjustment and stabilization after mixing. After the treatment is completed, the electrolytic fermentation broth is obtained.

[0022] In one embodiment of the present invention: in step 4, insect protein extract, marine biosource polysaccharide and microbial metabolite complex are selected as nutrient additives, and their addition amounts are 8%-12%, 5%-7% and 4%-8% of the total weight of the electrolytic fermentation liquid, respectively; trace elements are iron, zinc, copper and manganese, and the trace elements are added in the form of organic chelates, and their addition amounts are 0.3%-0.5%, 0.07%-0.2%, 0.08%-0.1% and 0.05%-0.02% of the total weight of the electrolytic fermentation liquid, and the nutrient additives and trace elements are slowly added to the electrolytic fermentation liquid in sequence, and stirred at a stirring rate of 30r / min.

[0023] In one embodiment of the present invention: in step 4, after stirring is completed, a microwave device is used to treat the mixed liquid, the microwave frequency is set to 2450MHz, the power is 800W-1200W, and the treatment is 20min-30min. During the treatment process, circulating water cooling is used to control the liquid temperature at 35°C-40°C. After the microwave-assisted treatment is completed, a mixed solution is obtained, and a natural stabilizer is added and mixed in an amount of 2%-4% of the total weight of the mixed solution. Stirring is continued for 15min to fully mix the natural stabilizer and the mixed solution to obtain a liquid fertilizer.

[0024] In one embodiment of the present invention: in step five, for each batch of liquid fertilizer produced, 5-8 samples need to be taken for testing. After the liquid fertilizer is prepared, samples are taken from the top, middle and bottom of the storage container for testing. The nutrient component testing includes the testing of nitrogen, phosphorus, potassium and trace elements, and stability and safety testing are also performed.

[0025] In one embodiment of the present invention: the magnetized filtering device is mainly composed of a high-strength permanent magnet array and a special filtering medium. The permanent magnet array is made of neodymium iron boron material, and the magnetic field strength can reach 1.5 Tesla. The filtering medium is a specially treated nanofiber material with a fiber diameter between 50-100 nanometers, which has high adsorption performance and good chemical stability.

[0026] In one embodiment of the present invention: the polysaccharide complex is extracted from specific marine microorganisms and has good water retention and nutrient sustained-release properties; the bioactive enzyme preparation is compounded by a special process of multiple natural enzymes and can promote the decomposition and conversion of organic matter in fertilizers; the alkaloid extract is extracted from specific medicinal plants and has the effect of enhancing plant resistance to stress.

[0027] In one embodiment of the present invention: in step five, the aseptic filling operation is performed, and an aseptic filling production line that meets medical grade standards is selected, including a filling machine, a sealing machine and a conveying equipment, and an aseptic filling workshop is established. At the same time, the air cleanliness in the workshop is maintained at level 100, that is, the number of dust particles with a particle size greater than or equal to 0.5um per cubic meter of air does not exceed 3500, and the air is continuously filtered and purified through high-efficiency air filters, laminar flow hoods and other equipment.

[0028] Embodiment 1 900 kg of histidine fermentation waste liquid was collected, and the pH value was adjusted to 7.2 with a natural acid-base regulator. Two layers of micro-nano filtration membranes were used for filtration. The pore size of the first layer of filtration membrane was 0.1 um, and the pore size of the second layer of filtration membrane was 0.05 um. The filtration pressure was controlled to be 0.23 MPa, the filtration temperature was 30°C, and the filtration flow rate was 3.8 L / min. After the filtration was completed, the filter membrane was backwashed once per hour, and the backwashing pressure was 0.34 MPa. After the filtration was completed, it was transferred to a magnetization filtration device through a corrosion-resistant pipe (inner diameter 50 mm, flow rate 2 L / min). The histidine fermentation liquid first passed through the preliminary magnetic field area and then entered the main adsorption area, in which metal ions and magnetic particles were adsorbed onto the nanofiber filtration medium by the strong magnetic field to obtain histidine fermentation liquid. The histidine fermentation liquid was transferred into a corrosion-resistant container, the temperature was adjusted to 43°C, the pressure was set to 12MPa, the CO2 flow rate was controlled to 6.5L / min, the extraction time was set to 3.3h, and the stirring rate during the extraction process was 33r / min. After the extraction was completed, the supercritical CO2 fluid containing the active ingredient entered the separation device through a specific pipeline, the temperature of the separation device was adjusted to 35°C, the pressure was reduced to 6MPa, the CO2 was converted from a supercritical state to a gaseous state, and the active ingredient was collected in a glass storage container and placed in a cool and dry environment (temperature controlled at 21°C) for standby use; A multi-stage corrosion-resistant reactor was selected, 400 kg of histidine fermentation broth (accounting for 44.4% of the total volume of the reactor) was added to the first-stage reaction area, and then 48 kg of the extracted active ingredients (accounting for 12% of the total weight of the fermentation broth) were slowly added, and then 24 kg of polysaccharide complex (accounting for 6% of the total weight of the fermentation broth), 15 kg of biologically active enzyme preparation (accounting for 3.75% of the total weight of the fermentation broth) and 12 kg of alkaloid extract (accounting for 3% of the total weight of the fermentation broth) were added, and stirred to mix thoroughly to obtain a mixed fermentation broth. Electrode plates were installed in the three reaction areas of the reactor respectively, and the mixture was stirred. After the completion of the reaction, the electrolysis voltage in the reaction area was controlled to be 33V, 36V, and 38V, the current density was 6.5A / dm², and the electrolysis time was controlled at 2.3h. During the electrolysis process, the circulating cooling system of the reactor was used to control the reaction temperature at 37°C. The circulating cooling medium was deionized water with a flow rate of 15L / min. At the same time, stirring was performed. The stirring speed of the first-stage reaction area was 43r / min, the stirring speed of the second-stage reaction area was 33r / min, and the stirring speed of the third-stage reaction area was 23r / min. After the treatment was completed Electrolytic fermentation liquid was prepared, and insect protein extract, marine biogenic polysaccharide and microbial metabolite complex were selected as nutrient additives, and the addition amounts were 10%, 6% and 5% of the total weight of the electrolytic fermentation liquid, i.e., 54kg, 32.4kg and 27kg, respectively. Trace elements were iron, zinc, copper and manganese, which were added in the form of organic chelates, and the addition amounts were 0.4%, 0.1%, 0.08% and 0.03% of the total weight of the electrolytic fermentation liquid, i.e., 1.8kg, 0.45kg, 0.36kg, 0. 135kg, nutrient additives and trace elements are slowly added to the electrolytic fermentation liquid in order, and stirred at a stirring rate of 30r / min. After stirring, the mixed liquid is treated with a microwave device, the microwave frequency is set to 2450MHz, the power is 1000W, and the treatment is 25min. During the treatment, circulating water cooling is used to control the liquid temperature at 38℃. After the microwave-assisted treatment is completed, a natural stabilizer is added in an amount of 3% of the total weight of the mixed solution. Stirring is continued for 15min to obtain a liquid fertilizer.

[0029] Embodiment 2 1000 kg of histidine fermentation waste liquid was collected, and the pH value was adjusted to 7.0 with a natural acid-base regulator. Two layers of micro-nano filtration membranes were used for filtration, with the pore size of the first layer of filtration membrane being 0.1 um and the pore size of the second layer of filtration membrane being 0.05 um. The filtration pressure was controlled to be 0.22 MPa, the filtration temperature to be 30°C, the filtration flow rate to be 3.5 L / min, the backwashing frequency to be once per hour, and the backwashing pressure to be 0.33 MPa. After the filtration was completed, it was transferred to a magnetization filtration device through a corrosion-resistant pipe (inner diameter 50 mm, flow rate 2 L / min). The fermentation liquid first passed through a preliminary magnetic field area and then entered a main adsorption area, where metal ions and magnetic particles were adsorbed onto the nanofiber filtration medium by a strong magnetic field to obtain histidine fermentation liquid. The histidine fermentation liquid was transferred into a corrosion-resistant container, the temperature was adjusted to 45°C, the pressure was set to 12MPa, the CO2 flow rate was controlled to 6L / min, the extraction time was set to 3.5h, and the stirring rate during the extraction process was 35r / min. After the extraction was completed, the supercritical CO2 fluid containing the active ingredient entered the separation device through a specific pipeline, the temperature of the separation device was adjusted to 35°C, the pressure was reduced to 6MPa, the CO2 was converted from a supercritical state to a gaseous state, and the active ingredient was collected in a glass storage container and placed in a cool and dry environment (temperature controlled at 22°C) for standby use; A multi-stage corrosion-resistant reactor was selected, and 450 kg of histidine fermentation broth (accounting for 45% of the total volume of the reactor) was added to the first-stage reaction area, and then 54 kg of the extracted active ingredients (accounting for 12% of the total weight of the fermentation broth) were slowly added, and then 27 kg of polysaccharide complex (accounting for 6% of the total weight of the fermentation broth), 18 kg of biologically active enzyme preparation (accounting for 4% of the total weight of the fermentation broth) and 13.5 kg of alkaloid extract (accounting for 3% of the total weight of the fermentation broth) were added, and stirred thoroughly to obtain a mixed fermentation broth. Electrode plates were installed in the three reaction areas of the reactor. After mixing, The electrolysis voltage in the reaction area is controlled to be 32V, 35V, and 38V, the current density is 6A / dm², and the electrolysis time is controlled to be 2.5h. During the electrolysis process, the circulating cooling system of the reactor is used to control the reaction temperature at 38°C. Deionized water is used as the circulating cooling medium with a flow rate of 15L / min. At the same time, stirring operation is performed. The stirring speed of the first-stage reaction area is 45r / min, the stirring speed of the second-stage reaction area is 35r / min, and the stirring speed of the third-stage reaction area is 25r / min. After the treatment is completed, the electrolytic fermentation liquid is obtained. Insect protein extract, marine biosource polysaccharide and microbial metabolite complex were selected as nutritional additives, and their addition amounts were 10%, 6% and 5% of the total weight of the electrolytic fermentation liquid, i.e. 58.5kg, 35.1kg and 29.25kg respectively. Trace elements were iron, zinc, copper and manganese, added in the form of organic chelates, and their addition amounts were 0.4%, 0.1%, 0.09% and 0.03% of the total weight of the electrolytic fermentation liquid, i.e. 2.34kg, 0.585kg, 0.5265kg and 0. 1755kg, nutrient additives and trace elements are slowly added to the electrolytic fermentation liquid in order, and stirred at a stirring rate of 30r / min. After stirring, the mixed liquid is treated with a microwave device, the microwave frequency is set to 2450MHz, the power is 1000W, and the treatment is 25min. During the treatment process, circulating water cooling is used to control the liquid temperature at 38℃. After the microwave-assisted treatment is completed, a natural stabilizer is added in an amount of 3% of the total weight of the mixed solution. Stirring is continued for 15min to obtain a liquid fertilizer.

[0030] Embodiment 3 1200 kg of histidine fermentation waste liquid was collected, and the pH value was adjusted to 6.8 with a natural acid-base regulator. Two layers of micro-nano filtration membranes were used for filtration, with the pore size of the first layer of filtration membrane being 0.1 um and the pore size of the second layer of filtration membrane being 0.05 um. The filtration pressure was controlled to be 0.2 MPa, the filtration temperature to be 30°C, the filtration flow rate to be 3 L / min, the backwashing frequency to be once per hour, and the backwashing pressure to be 0.3 MPa. After the filtration was completed, it was transferred to a magnetization filtration device through a corrosion-resistant pipe (inner diameter 50 mm, flow rate 2 L / min). The fermentation liquid first passed through a preliminary magnetic field area and then entered a main adsorption area, where metal ions and magnetic particles were adsorbed onto the nanofiber filtration medium by a strong magnetic field to obtain histidine fermentation liquid. The histidine fermentation liquid was transferred into a corrosion-resistant container, the temperature was adjusted to 48°C, the pressure was set to 12MPa, the CO2 flow rate was controlled to 7L / min, the extraction time was set to 3.8h, and the stirring rate during the extraction process was 38r / min. After the extraction was completed, the supercritical CO2 fluid containing the active ingredient entered the separation device through a specific pipeline, the temperature of the separation device was adjusted to 35°C, the pressure was reduced to 6MPa, the CO2 was converted from a supercritical state to a gaseous state, and the active ingredient was collected in a glass storage container and placed in a cool and dry environment (temperature controlled at 23°C) for standby use; A multi-stage corrosion-resistant reactor was selected, and 550 kg of histidine fermentation broth (accounting for 45.8% of the total volume of the reactor) was added to the first-stage reaction area, and then 66 kg of the extracted active ingredients (accounting for 12% of the total weight of the fermentation broth) were slowly added, and then 33 kg of polysaccharide complex (accounting for 6% of the total weight of the fermentation broth), 22 kg of biologically active enzyme preparation (accounting for 4% of the total weight of the fermentation broth) and 16.5 kg of alkaloid extract (accounting for 3% of the total weight of the fermentation broth) were added, and stirred thoroughly to obtain a mixed fermentation broth. Electrode plates were installed in the three reaction areas of the reactor. After mixing, The electrolysis voltage in the reaction area is controlled to be 33V, 36V, and 39V, the current density is 7A / dm², and the electrolysis time is controlled to be 2.8h. During the electrolysis process, the circulating cooling system of the reactor is used to control the reaction temperature at 39°C. The circulating cooling medium is deionized water with a flow rate of 15L / min. At the same time, stirring operation is performed. The stirring speed of the first-stage reaction area is 48r / min, the stirring speed of the second-stage reaction area is 38r / min, and the stirring speed of the third-stage reaction area is 28r / min. After the treatment is completed, the electrolytic fermentation liquid is obtained. Insect protein extract, marine biosource polysaccharide and microbial metabolite complex were selected as nutritional additives, and their addition amounts were 11%, 6.5% and 6% of the total weight of the electrolytic fermentation liquid, i.e. 74.35kg, 41.4kg and 39.3kg respectively. Trace elements were iron, zinc, copper and manganese, added in the form of organic chelates, and their addition amounts were 0.45%, 0.15%, 0.08% and 0.04% of the total weight of the electrolytic fermentation liquid, i.e. 3.105kg, 0.84kg, 0.672kg and 0. 288kg, nutrient additives and trace elements are slowly added to the electrolytic fermentation liquid in order, and stirred at a stirring rate of 30r / min. After stirring, the mixed liquid is treated with a microwave device, the microwave frequency is set to 2450MHz, the power is 1100W, and the treatment is 28min. During the treatment, circulating water cooling is used to control the liquid temperature at 39℃. After the microwave-assisted treatment is completed, a natural stabilizer is added in an amount of 3.5% of the total weight of the mixed solution. Stirring is continued for 15min to obtain liquid fertilizer.

[0031] Embodiment 4: 800 kg of histidine fermentation waste liquid was collected, and the pH value was adjusted to 7.3 with a natural acid-base regulator. Two layers of micro-nano filtration membranes were used for filtration, with the pore size of the first layer of filtration membrane being 0.1 um and the pore size of the second layer of filtration membrane being 0.05 um. The filtration pressure was controlled to be 0.24 MPa, the filtration temperature to be 30°C, the filtration flow rate to be 3.9 L / min, the backwashing frequency to be once per hour, and the backwashing pressure to be 0.36 MPa. After the filtration was completed, it was transferred to a magnetization filtration device through a corrosion-resistant pipe (inner diameter 50 mm, flow rate 2 L / min). The fermentation liquid first passed through a preliminary magnetic field area and then entered the main adsorption area, where metal ions and magnetic particles were adsorbed onto the nanofiber filtration medium by a strong magnetic field to obtain histidine fermentation liquid. The histidine fermentation liquid was transferred into a corrosion-resistant container, the temperature was adjusted to 44°C, the pressure was set to 12MPa, the CO2 flow rate was controlled to 6.2L / min, the extraction time was set to 3.4h, and the stirring rate during the extraction process was 34r / min. After the extraction was completed, the supercritical CO2 fluid containing the active ingredient entered the separation device through a specific pipeline, the temperature of the separation device was adjusted to 35°C, the pressure was reduced to 6MPa, the CO2 was converted from a supercritical state to a gaseous state, and the active ingredient was collected in a glass storage container and placed in a cool and dry environment (temperature controlled at 21.5°C) for standby use; A multi-stage corrosion-resistant reactor was selected, and 360 kg of histidine fermentation broth (accounting for 45% of the total volume of the reactor) was added to the first-stage reaction area, and then 43.2 kg of the extracted active ingredients (accounting for 12% of the total weight of the fermentation broth) were slowly added, and then 21.6 kg of polysaccharide complex (accounting for 6% of the total weight of the fermentation broth), 14.4 kg of biologically active enzyme preparation (accounting for 4% of the total weight of the fermentation broth) and 10.8 kg of alkaloid extract (accounting for 3% of the total weight of the fermentation broth) were added, and stirred to mix thoroughly to obtain a mixed fermentation broth. Electrode plates were installed in the three reaction areas of the reactor, and the mixing was completed. The electrolysis voltage in the reaction area was then controlled to be 31V, 34V, and 37V, the current density was 6.2A / dm², and the electrolysis time was controlled to be 2.4h. During the electrolysis process, the circulating cooling system of the reactor was used to control the reaction temperature to be 37.5°C. Deionized water was used as the circulating cooling medium with a flow rate of 15L / min. At the same time, stirring was performed. The stirring speed of the first-stage reaction area was 44r / min, the stirring speed of the second-stage reaction area was 34r / min, and the stirring speed of the third-stage reaction area was 24r / min. After the treatment was completed, the electrolytic fermentation liquid was obtained. Insect protein extract, marine biosource polysaccharide and microbial metabolite complex were selected as nutritional additives, and their addition amounts were 9.5%, 5.8% and 4.8% of the total weight of the electrolytic fermentation liquid, i.e. 40.86kg, 26.64kg and 23.04kg respectively. Trace elements were iron, zinc, copper and manganese, added in the form of organic chelates, and their addition amounts were 0.38%, 0.12%, 0.075% and 0.025% of the total weight of the electrolytic fermentation liquid, i.e. 1.52kg, 0.48kg and 0.36kg respectively. g, 0.1kg, nutrient additives and trace elements are slowly added to the electrolytic fermentation liquid in order, and stirred at a stirring rate of 30r / min. After stirring, the mixed liquid is treated with a microwave device, the microwave frequency is set to 2450MHz, the power is 950W, and the treatment is 26min. During the treatment, circulating water cooling is used to control the liquid temperature at 37.5℃. After the microwave-assisted treatment is completed, a natural stabilizer is added in an amount of 3.2% of the total weight of the mixed solution. Stirring is continued for 15min to obtain liquid fertilizer.

[0032] The liquid fertilizer products prepared in the above four groups of embodiments were subjected to quality inspection, and the inspection method was as follows: pH value detection, Place the liquid fertilizer sample in a certain temperature environment (such as room temperature), measure its pH value every 2 hours, and take the average pH value.

[0033] Nutritional testing, The Kjeldahl method is used, and a fully automatic Kjeldahl nitrogen analyzer is used to weigh a certain amount of liquid fertilizer sample, and concentrated sulfuric acid and other reagents are added for digestion to convert the organic nitrogen in the sample into ammonium nitrogen. After the digestion is completed, distillation is performed to distill out the ammonium nitrogen, absorb it with a boric acid solution, and then the absorption liquid is titrated with a standard hydrochloric acid solution. The nitrogen content is calculated based on the amount of hydrochloric acid consumed. The sample digestion time is 1h-2h, and the distillation time is 5min-10min; The molybdenum antimony colorimetric method is adopted, and a visible spectrophotometer is used. First, a phosphorus standard solution is prepared, and a standard curve is drawn. A certain amount of liquid fertilizer sample is taken, and reagents such as ammonium molybdate and ascorbic acid are added. Under certain conditions, a phosphorus-molybdenum blue complex is generated, and then the absorbance is measured at a wavelength of 700nm, and the phosphorus content is calculated according to the standard curve. The flame photometry method was used to dilute the liquid fertilizer sample and then measure it with a flame photometer. The detection accuracy of the flame photometer was ±0.5 mg / L. After adjusting the instrument parameters and stabilizing the instrument, the potassium emission light intensity of the sample solution was measured in turn, and the potassium content was calculated based on the standard curve.

[0034] Heavy metal detection (lead, cadmium, mercury, etc.), Lead detection: Atomic absorption spectrometry is used, the wavelength of the lead hollow cathode lamp is 283.3nm, and the sample pretreatment adopts microwave digestion method, using a polytetrafluoroethylene digestion tank, the digestion temperature is 180℃-220℃, and the digestion time is 20min-30min. After the digestion is completed, the sample solution is sprayed into the flame of the atomic absorption spectrometer to measure the absorbance of the lead element, and the lead content is calculated according to the standard curve; Cadmium detection: The wavelength of the cadmium hollow cathode lamp is 228.8nm, and the other operating steps are similar to those of lead detection; Mercury detection: The wavelength of the mercury hollow cathode lamp is 253.7nm, and the sample pretreatment and instrument determination are also performed.

[0035] The calculation results are as follows: Embodiment 1

[0036] pH: 6.8; Nutritional content: Nitrogen content is 2.5%, phosphorus content is 1.2%, potassium content is 2.0%; Heavy metal detection: None.

[0037] Embodiment 2 pH: 6.9; Nutritional content: Nitrogen content is 2.8%, phosphorus content is 1.3%, potassium content is 2.2%; Heavy metal detection: None.

[0038] Embodiment 3 pH: 7.1; Nutritional content: 3.2% nitrogen, 1.5% phosphorus, 2.5% potassium; Heavy metal detection: None.

[0039] Embodiment 4: pH: 7.0; Nutritional content: Nitrogen content is 2.3%, phosphorus content is 1.1%, potassium content is 1.8%; Heavy metal detection: None.

[0040] In summary, the feasibility and effectiveness of preparing fertilizer from histidine fermentation waste liquid in the four groups of embodiments of the present invention have important practical significance and application value.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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 fertilizer from histidine fermentation waste liquid, comprising pretreatment of histidine fermentation waste liquid, extraction treatment, electrolysis of fermentation waste liquid, addition of nutrients and quality testing, characterized in that: The specific operation steps of preparing fertilizer from histidine fermentation waste liquid are as follows: Step 1: collecting the histidine fermentation waste liquid, filtering it with a micro-nano filtration membrane, and transferring it to a magnetic filtration device for adsorption separation after filtration, and obtaining a histidine fermentation liquid; Step 2: Transfer the histidine fermentation liquid into a container, use supercritical fluid extraction technology, use CO2 as a supercritical fluid, extract the active ingredients in the histidine fermentation waste liquid and temporarily store it for later use; Step 3: adding the extracted active ingredients, polysaccharide complexes, bioactive enzyme preparations, alkaloid extracts and histidine fermentation broth into a multi-stage reactor and performing electrolysis treatment to obtain an electrolytic fermentation broth; Step 4: transfer the electrolytic fermentation liquid into a corrosion-resistant container, add nutrient additives and trace elements, stir and mix, and use a microwave device for microwave-assisted treatment. After completion, add a natural stabilizer to obtain a liquid fertilizer; Step 5: Sample the prepared liquid fertilizer and conduct a quality inspection on it. If it passes the inspection, it will be filled in a sterile environment and stored in a dry and ventilated environment.

2. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In the step 1, the pH value of the collected histidine fermentation waste liquid is adjusted, and a natural acid-base regulator is added to adjust the pH value of the histidine fermentation waste liquid to 6.5-7.

5. After the adjustment is completed, the histidine fermentation waste liquid is filtered using a micro-nano filtration membrane. The filtration device uses a two-layer filtration structure, the pore size of the first layer of the filtration membrane is 0.1um, and the pore size of the second layer of the filtration membrane is 0.05um. During the multi-group filtration process, the filtration pressure is controlled to be 0.2MPa-0.25MPa, the filtration temperature is 30°C, and the filtration flow rate is 3L / min-4L / min. At the same time, backwashing operation is performed regularly during the filtration process, the backwashing frequency is once per hour, and the backwashing pressure is 1.5 times the filtration pressure.

3. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In the step 1, after the filtration is completed, the waste liquid is transferred to a magnetic filtration device for adsorption separation, the filtered fermentation liquid is introduced into the inlet of the magnetic filtration device through a corrosion-resistant pipe, the inner diameter of the pipe is 50 mm, and the flow rate is controlled at 2 L / min. After the fermentation liquid enters the magnetic filtration device, it first passes through a preliminary magnetic field area to preliminarily magnetize the metal ions and magnetic particles in the histidine fermentation waste liquid, the fermentation liquid enters the main adsorption area, the metal ions and magnetic particles are adsorbed onto the nanofiber filter medium by the strong magnetic field, and the histidine fermentation waste liquid flows out from the outlet of the magnetic filtration device after the magnetic filtration treatment to obtain the histidine fermentation liquid.

4. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In the step 2, the histidine fermentation broth is transferred into a corrosion-resistant container, the temperature is adjusted to 40°C-50°C, the pressure is set to 12MPa, the flow rate of CO2 is controlled to 5L / min-8L / min, the extraction time is set to 3h-4h, and during the extraction process, the histidine fermentation broth is slowly stirred using a stirring device at a stirring rate of 30r / min-40r / min. After the extraction is completed, the supercritical CO2 fluid containing the active ingredient enters the separation device through a specific pipeline, the temperature of the separation device is adjusted to 35°C, the pressure is reduced to 6MPa, CO2 is converted from a supercritical state to a gaseous state, and the active ingredient is collected in a glass storage container, placed in a cool and dry environment, the temperature is controlled at 20°C-25°C, and stored for later use.

5. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In the step 3, a specially made multi-stage corrosion-resistant reactor is selected, and the reactor is divided into three independent reaction areas, each area can independently control the temperature, pressure and stirring speed, and the histidine fermentation liquid is added to the first-stage reaction area in the reactor, and the amount of the histidine fermentation liquid added is controlled to be 40%-50% of the total volume of the reactor, and then the extracted active ingredients are slowly added to the histidine fermentation liquid, and the amount of the active ingredients added is 10%-15% of the total weight of the histidine fermentation liquid. Then, the polysaccharide complex, the bioactive enzyme preparation and the alkaloid extract are added, and the addition amounts are 5%-8%, 3%-5% and 3%-4% of the total weight of the histidine fermentation liquid, respectively, and they are stirred and mixed to obtain a mixed fermentation liquid.

6. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In step 3, electrode plates are installed in the three reaction areas of the reactor. After the histidine and the material components are mixed, the electrolysis voltage in the reaction area is controlled to be 30V-40V and the current density is 5A / dm 2 -8A / dm 2 The electrolysis time is controlled between 2h-3h. During the electrolysis process, the circulating cooling system of the reactor is used to control the reaction temperature at 35℃-40℃. Deionized water is selected as the circulating cooling medium with a flow rate of 15L / min. During the electrolysis treatment, stirring operation is performed simultaneously. The stirring speed of the first-stage reaction area is 40r / min-50r / min, which is mainly used for preliminary mixing and reaction to fully mix the histidine fermentation broth and the active ingredients. The stirring speed of the second-stage reaction area is 30r / min-40r / min, which is mainly used for the interaction between the polysaccharide complex, the bioactive enzyme preparation and the alkaloid extract and the histidine fermentation broth. The stirring speed of the third-stage reaction area is 20r / min-30r / min, which is mainly used for adjustment and stabilization after mixing. After the treatment is completed, the electrolytic fermentation broth is obtained.

7. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In the step 4, insect protein extract, marine biosource polysaccharide and microbial metabolite complex are selected as nutrient additives, and the added amounts thereof are 8%-12%, 5%-7% and 4%-8% of the total weight of the electrolytic fermentation liquid, respectively. Trace elements are selected from iron, zinc, copper and manganese, and the trace elements are added in the form of organic chelates, and the added amounts thereof are 0.3%-0.5%, 0.07%-0.2%, 0.08%-0.1% and 0.05%-0.02% of the total weight of the electrolytic fermentation liquid, respectively. The nutrient additives and trace elements are slowly added to the electrolytic fermentation liquid in sequence, and stirred at a stirring rate of 30 r / min.

8. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In the step 4, after the stirring is completed, the mixed liquid is treated with a microwave device, the microwave frequency is set to 2450MHz, the power is 800W-1200W, and the treatment is carried out for 20min-30min. During the treatment process, circulating water cooling is used to control the liquid temperature at 35°C-40°C. After the microwave-assisted treatment is completed, a mixed solution is obtained, and a natural stabilizer is added and mixed in an amount of 2%-4% of the total weight of the mixed solution. The stirring is continued for 15min to fully mix the natural stabilizer and the mixed solution to obtain a liquid fertilizer.

9. The method for preparing fertilizer from histidine fermentation waste liquid according to claim 1, characterized in that: In step 5, 5-8 samples need to be taken for testing for each batch of liquid fertilizer produced. After the liquid fertilizer is prepared, samples are taken from the top, middle and bottom of the storage container for testing. The nutrient component testing includes the testing of nitrogen, phosphorus, potassium and trace elements, and stability and safety testing are also performed.

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