CN112189531A

CN112189531A - Method for preparing slow-release culture soil based on kitchen waste

Info

Publication number: CN112189531A
Application number: CN202010987661.3A
Authority: CN
Inventors: 施亚琼
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-09-18
Filing date: 2020-09-18
Publication date: 2021-01-08

Abstract

The invention provides a method for preparing slow-release culture soil based on kitchen waste, and relates to the technical field of culture soil preparation, wherein the culture soil is prepared from the following raw materials in parts by weight: 30-45 parts of kitchen waste, 0.5-1 part of compound microbial agent, 50-100 parts of buckwheat hulls, 3-10 parts of urea, 3-10 parts of potassium sulfate, 3-10 parts of calcium superphosphate, 80-120 parts of modified bentonite, 10-20 parts of ground phosphate rock and 15-30 parts of perlite. The slow-release type culture soil prepared by the method has the advantages of excellent slow-release performance, small smell, capability of recycling kitchen waste, reduction of pressure of municipal solid waste treatment and the like.

Description

Method for preparing slow-release culture soil based on kitchen waste

Technical Field

The invention relates to the technical field of breeding soil preparation, in particular to a method for preparing slow-release breeding soil based on kitchen waste.

Background

The kitchen waste refers to waste and residues generated in food processing and dining processes in resident families, catering industries and dining halls of enterprises and public institutions, and has the characteristics of high water content, rich nutrient substances, high biodegradability and the like. At present, the treatment mode of kitchen waste in China mainly comprises feeding livestock, most of the rest is mixed with municipal domestic waste and then is buried, burned or composted, so that the serious problems of environmental pollution and environmental safety are caused, and the urban sanitary environment and the daily life of residents are seriously influenced. And along with the continuous improvement of the living standard of people, the annual output of the kitchen waste is continuously increased, and the treatment difficulty of the kitchen waste is aggravated.

The ingredients of the kitchen waste are relatively unstable, are greatly influenced by regional differences, folk custom, eating habits and the like, but have certain similarity on the whole, and except food components such as rice flour oil, vegetables and fruits, meat, seafood shells, bones and the like, sundries such as disposable tableware, paper towels, plastics and the like are often mixed. The kitchen waste in China has the following characteristics on the whole: the water content is higher, and can generally reach 70 to 85 percent. The high water content leads the heat value of the kitchen waste to be low, which is not beneficial to incineration treatment; in addition, the high water content also causes great inconvenience to the collection, transportation and further treatment of the kitchen waste to a certain extent; the pH is generally between 4.0 and 6.8 and is acidic; the organic matter accounts for a relatively high proportion, generally can reach about 95% -98% of the dry matter content, wherein the proportion of starch and protein in the organic component is as high as about 60%, the oil content accounts for 15% -30% of the dry matter, and the cellulose content is relatively low; the C/N ratio is generally between 15 and 40, the content of N, P, K and other elements is high, and the kitchen waste has a high recycling value, but the salt content of the kitchen waste can be as high as 1.5 to 5 percent (calculated by chloride ions), so the kitchen waste is treated by a biochemical treatment method, but cannot be treated by a landfill method directly.

As the main by-product of buckwheat, the buckwheat hulls account for about one third of the total weight of buckwheat, and except that part of the buckwheat hulls are made into the buckwheat pillow, most of the remaining buckwheat hulls are treated by base fertilizer or incineration, so that the reasonable utilization rate is extremely low. The triangular shell of the common buckwheat is firm but not hard, a perfect ventilation channel can be naturally formed between shells due to the special triangular prism structure, the elasticity and the ventilation property are good, in addition, the components of the buckwheat shells are mostly cellulose, lignin and other substances, and nutrient components are provided for the culture soil.

The kitchen waste is prepared into the breeding soil, so that the nutrient substances in the kitchen waste can be recycled, the leaching content of heavy metals in the kitchen waste is obviously lower than the relevant limit values of the limit of mercury, arsenic, cadmium, lead and chromium of water-soluble fertilizers and the content measurement thereof (ny1110-2006), the problem that the heavy metals in the breeding soil exceed the standard can be effectively avoided, the slow-release breeding soil is prepared by utilizing the kitchen waste and the slow-release components, the utilization rate of the breeding soil is improved, the fertilizer efficiency is longer than that of the common breeding soil, the leaching volatilization loss is reduced, and the purpose of saving the cost is achieved.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a method for preparing slow-release type culture soil based on kitchen waste, the slow-release type culture soil is prepared from the kitchen waste, a compound microbial agent, buckwheat shells, urea, potassium sulfate, calcium superphosphate, modified bentonite, ground phosphate rock, perlite and the like, and the slow-release type culture soil has the advantages of long fertilizer effect, small smell, recycling of the kitchen waste, reduction of pollution of household garbage and the like.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme:

a slow-release cultivation soil prepared based on kitchen waste comprises the following raw materials in parts by weight: 30-45 parts of kitchen waste, 0.5-1 part of compound microbial agent, 50-100 parts of buckwheat hulls, 3-10 parts of urea, 3-10 parts of potassium sulfate, 3-10 parts of calcium superphosphate, 80-120 parts of modified bentonite, 10-20 parts of ground phosphate rock and 15-30 parts of perlite.

Further, the preparation method of the slow-release culture soil comprises the following steps:

(1) crushing and sterilizing fresh kitchen waste, and adding the kitchen waste into a composting reactor, wherein a stirring device and a ventilation device are arranged in the composting reactor;

(2) uniformly mixing the compound microbial agent and the buckwheat hulls, inoculating the mixture into kitchen waste, and performing degradation treatment for 10 days at the temperature of 30-40 ℃ and the humidity of 70-80% to obtain compost;

(3) ball-milling and mixing the modified bentonite, the ground phosphate rock, the urea, the potassium sulfate, the calcium superphosphate and the perlite to obtain a mixture;

(4) uniformly mixing the mixture obtained in the step (3) with the compost obtained in the step (2), and composting for 20 days at the temperature of 40-50 ℃ and the humidity of 70% -80% to obtain a degradation product;

(5) taking out the degradation product obtained in the step (4) from the compost reactor, and naturally drying for 1-2 days to obtain culture soil;

(6) and putting the breeding soil into a granulator, granulating by using water as an adhesive, and drying at a low temperature of 70-80 ℃ to obtain the slow-release breeding soil.

Further, in the step (2) of the preparation method of the slow-release culture soil, the composting reactor is ventilated for 30-60 minutes every 4-4.5 hours in the composting process.

Further, in the step (6) of the preparation method of the slow-release culture soil, the particle diameter of the slow-release culture soil is controlled to be 2-5 mm.

Further, the total viable bacteria concentration of the compound microbial agent is (2-3) × 10¹¹cfu/g, the number ratio of viable bacteria is 1:1.5:1: (1-1.5):2:1 of thermophilic bacillus, candida lipolytica, aspergillus oryzae, bacillus licheniformis, trichoderma viride and azotobacter chroococcum.

Further, the preparation method of the modified bentonite comprises the following steps:

(1) weighing bentonite and Na₂CO₃Mixing with water, and stirring in water bath at 60-70 deg.C for 1.5-2 hr to obtain paste;

(2) drying, crushing and sieving the paste obtained in the step (1) to obtain powdery bentonite;

(3) adding polyvinylpyrrolidone and water into a container with an ultrasonic cleaning instrument arranged at the bottom, carrying out ultrasonic oscillation for 45-60 minutes until the polyvinylpyrrolidone and the water are completely dissolved, adding the powdery bentonite obtained in the step (1), and fully and uniformly mixing;

(4) starting an ultrasonic cleaning instrument, and performing ultrasonic dispersion for a period of time to obtain a mixture;

(5) and (4) drying the mixture obtained in the step (4) in an oven at 50-60 ℃, grinding the dried mixture and sieving the dried mixture through a 230-one 270-mesh sieve to obtain the modified bentonite.

Further, the preparation method of the modified bentonite comprises the steps of (1) preparing bentonite and Na₂CO₃The mass ratio to water is 25: 1: (120-140).

Further, the paste obtained in the step (2) of the preparation method of the modified bentonite is dried and crushed at the temperature of 100-120 ℃ and then passes through a 230-270-mesh sieve.

Furthermore, in the preparation method of the modified bentonite, in the step (4), the mass ratio of the polyvinylpyrrolidone to the water to the powdery bentonite is 1 (5-9) to 1.

Further, in the step (4) of the preparation method of the modified bentonite, ultrasonic dispersion is carried out for 50-70min under the conditions that the ultrasonic power is 100-.

(III) advantageous effects

The invention aims to overcome the problems in the prior art and provides a method for preparing slow-release type breeding soil based on kitchen waste.

The invention provides a method for preparing slow-release type culture soil based on kitchen waste.

According to the invention, the kitchen waste is biodegraded by using the compound microbial agent, the kitchen waste can be timely, quickly and efficiently degraded into an organic fertilizer, the thermophilic bacillus, the lipolytic candida, the aspergillus oryzae, the bacillus licheniformis and the trichoderma viride are respectively used for degrading starch, protein, grease, cellulose and other nutrients in the kitchen waste, the azotobacter chroococcum has the nitrogen fixation effect, the microecological balance of culture soil is adjusted, the harmful bacteria are inhibited and killed, the treatment amount and cost of municipal domestic waste are reduced, and the kitchen waste is subjected to harmless, quantitative reduction and resource treatment.

The buckwheat hulls are mixed with the compound microbial agent, perfect ventilation channels can be naturally formed between the hulls due to the special triangular prism structure, and the buckwheat hulls have good elasticity and ventilation property, and in addition, most of the buckwheat hulls contain cellulose, lignin and other substances, so that nutrient components are provided for the culture soil.

The modified bentonite is used as a slow release material to be mixed and granulated with the fermented kitchen waste, and the prepared slow release type culture soil has the advantage of good slow release performance.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

a slow-release cultivation soil prepared based on kitchen waste comprises the following raw materials in parts by weight: 30 parts of kitchen waste, 0.5 part of compound microbial agent, 50 parts of buckwheat shells, 3 parts of urea, 3 parts of potassium sulfate, 3 parts of calcium superphosphate, 80 parts of modified bentonite, 10 parts of ground phosphate rock and 15 parts of perlite.

The total viable bacteria concentration of the compound microbial agent is 2 multiplied by 10¹¹cfu/g, the composite microbial agent is prepared by mixing bacillus thermophilus, candida lipolytica, aspergillus oryzae, bacillus licheniformis, trichoderma viride and azotobacter chroococcum with the viable bacteria number ratio of 1:1.5:1:1:2: 1.

The preparation method of the slow-release culture soil comprises the following steps:

(2) uniformly mixing the compound microbial agent and the buckwheat hulls, inoculating the mixture into kitchen waste, performing degradation treatment for 10 days at the temperature of 30 ℃ and the humidity of 70%, and ventilating a composting reactor for 30 minutes every 4-hours in the composting process to obtain compost;

(4) uniformly mixing the mixture obtained in the step (3) with the compost obtained in the step (2), and composting for 20 days at 40 ℃ and 70% of humidity to obtain a degradation product;

(5) taking out the degradation product obtained in the step (4) from the compost reactor, and naturally drying for 1 day to obtain culture soil;

(6) and putting the breeding soil into a granulator, granulating by using water as an adhesive, controlling the diameter of the granules to be 2mm, and drying at a low temperature of 70 ℃ to obtain the slow-release breeding soil.

The preparation method of the modified bentonite comprises the following steps:

(1) weighing bentonite and Na₂CO₃Mixing with water, bentonite and Na₂CO₃The mass ratio to water is 25: 1: 130, stirring for 1.5 hours in a water bath at the constant temperature of 65 ℃ by an electric motor to obtain paste;

(2) drying and crushing the paste obtained in the step (1) at 100 ℃, then sieving the paste with a 270-mesh sieve, drying, crushing and sieving the powder to obtain powdery bentonite;

(3) adding polyvinylpyrrolidone and water into a container with an ultrasonic cleaning instrument arranged at the bottom, wherein the mass ratio of the polyvinylpyrrolidone to the water to the powdery bentonite is 1:5:1, carrying out ultrasonic oscillation for 45 minutes until the polyvinylpyrrolidone and the water are completely dissolved, adding the powdery bentonite obtained in the step (1), and fully and uniformly mixing;

(4) starting an ultrasonic cleaning instrument, and carrying out ultrasonic dispersion for 70min under the conditions of ultrasonic power of 100W and ultrasonic temperature of 40 ℃ to obtain a mixture;

(5) and (4) drying the mixture obtained in the step (4) in a drying oven at 60 ℃, grinding and sieving with a 270-mesh sieve after drying to obtain the modified bentonite.

Example 2:

a slow-release cultivation soil prepared based on kitchen waste comprises the following raw materials in parts by weight: 45 parts of kitchen waste, 1 part of compound microbial agent, 100 parts of buckwheat shells, 10 parts of urea, 10 parts of potassium sulfate, 10 parts of calcium superphosphate, 120 parts of modified bentonite, 20 parts of ground phosphate rock and 30 parts of perlite.

The total viable bacteria concentration of the compound microbial agent is 3 multiplied by 10¹¹cfu/g, the composite microbial agent is prepared by mixing bacillus thermophilus, candida lipolytica, aspergillus oryzae, bacillus licheniformis, trichoderma viride and azotobacter chroococcum according to the viable bacteria number ratio of 1:1.5:2: 1.

(2) uniformly mixing the compound microbial agent and the buckwheat hulls, inoculating the mixture into kitchen waste, performing degradation treatment for 10 days at the temperature of 40 ℃ and the humidity of 80%, and ventilating a composting reactor for 60 minutes every 4.5 hours in the composting process to obtain compost;

(4) uniformly mixing the mixture obtained in the step (3) with the compost obtained in the step (2), and composting for 20 days at 50 ℃ and 80% of humidity to obtain a degradation product;

(5) taking out the degradation product obtained in the step (4) from the compost reactor, and naturally drying for 2 days to obtain culture soil;

(6) and putting the breeding soil into a granulator, granulating by using water as an adhesive, controlling the diameter of the granules to be 5mm, and drying at a low temperature of 80 ℃ to obtain the slow-release breeding soil.

The preparation method of the modified bentonite was the same as that of the modified bentonite in example 1.

Example 3:

a slow-release cultivation soil prepared based on kitchen waste comprises the following raw materials in parts by weight: 30 parts of kitchen waste, 1 part of compound microbial agent, 50 parts of buckwheat shells, 10 parts of urea, 3 parts of potassium sulfate, 10 parts of calcium superphosphate, 80 parts of modified bentonite, 20 parts of ground phosphate rock and 15 parts of perlite.

The total viable bacteria concentration of the compound microbial agent is 3 multiplied by 10¹¹cfu/g, the composite microbial agent is prepared by mixing bacillus thermophilus, candida lipolytica, aspergillus oryzae, bacillus licheniformis, trichoderma viride and azotobacter chroococcum with the viable bacteria number ratio of 1:1.5:1:1:2: 1.

(2) uniformly mixing the compound microbial agent and the buckwheat hulls, inoculating the mixture into kitchen waste, performing degradation treatment for 10 days at the temperature of 40 ℃ and the humidity of 70%, and ventilating a composting reactor for 30 minutes every 4.5 hours in the composting process to obtain compost;

(4) uniformly mixing the mixture obtained in the step (3) with the compost obtained in the step (2), and composting for 20 days at 50 ℃ and 70% of humidity to obtain a degradation product;

(6) and putting the breeding soil into a granulator, granulating by using water as an adhesive, controlling the diameter of the granules to be 2mm, and drying at a low temperature of 80 ℃ to obtain the slow-release breeding soil.

Example 4:

a slow-release cultivation soil prepared based on kitchen waste comprises the following raw materials in parts by weight: 45 parts of kitchen waste, 0.5 part of compound microbial agent, 100 parts of buckwheat shells, 3 parts of urea, 10 parts of potassium sulfate, 3 parts of calcium superphosphate, 120 parts of modified bentonite, 10 parts of ground phosphate rock and 30 parts of perlite.

The total viable bacteria concentration of the compound microbial agent is 2 multiplied by 10¹¹cfu/g, the composite microbial agent is prepared by mixing bacillus thermophilus, candida lipolytica, aspergillus oryzae, bacillus licheniformis, trichoderma viride and azotobacter chroococcum according to the viable bacteria number ratio of 1:1.5:2: 1.

(2) uniformly mixing the compound microbial agent and the buckwheat hulls, inoculating the mixture into kitchen waste, performing degradation treatment for 10 days at the temperature of 30 ℃ and the humidity of 80%, and ventilating a composting reactor for 60 minutes every 4 hours in the composting process to obtain compost;

(4) uniformly mixing the mixture obtained in the step (3) with the compost obtained in the step (2), and composting for 20 days at 40 ℃ and 80% of humidity to obtain a degradation product;

(6) and putting the breeding soil into a granulator, granulating by taking water as an adhesive, controlling the diameter of the granules to be 5mm, and drying at a low temperature of 70 ℃ to obtain the slow-release breeding soil.

Example 5:

a slow-release cultivation soil prepared based on kitchen waste comprises the following raw materials in parts by weight: 40 parts of kitchen waste, 0.8 part of compound microbial agent, 80 parts of buckwheat shells, 5 parts of urea, 5 parts of potassium sulfate, 5 parts of calcium superphosphate, 100 parts of modified bentonite, 15 parts of ground phosphate rock and 25 parts of perlite.

The total viable bacteria concentration of the compound microbial agent is 2.5 multiplied by 10¹¹cfu/g, the composite microbial agent is prepared by mixing bacillus thermophilus, candida lipolytica, aspergillus oryzae, bacillus licheniformis, trichoderma viride and azotobacter chroococcum according to the viable bacteria number ratio of 1:1.5:2: 1.

(2) uniformly mixing the compound microbial agent and the buckwheat hulls, inoculating the mixture into kitchen waste, performing degradation treatment for 10 days at the temperature of 30-40 ℃ and the humidity of 70-80%, and ventilating a composting reactor for 30-60 minutes every 4-4.5 hours in the composting process to obtain compost;

(6) and putting the breeding soil into a granulator, granulating by using water as an adhesive, controlling the diameter of the granules to be 2-5mm, and drying at a low temperature of 70-80 ℃ to obtain the slow-release breeding soil.

Comparative example 1:

this comparative example compares with example 5, with no modified bentonite added, and the other contents and preparation steps are identical with example 5.

Cultivation soils were prepared according to the compositions and methods of examples 1 to 5 and comparative document 1, respectively. The treatment of the kitchen waste is mainly the treatment of macromolecular substances such as saccharides, fat, protein and the like in the kitchen waste. And the content of the macromolecular substances directly influences the final result of the kitchen waste treatment. Therefore, the carbohydrate, fat, protein and slow release performance in the kitchen waste are detected, and the moisture, carbohydrate, fat, protein and slow release performance in the kitchen waste after aerobic fermentation are detected.

(1) Detection of Total sugars

The total sugar content, measured as invert sugar, was determined by direct titration.

(ii) sample treatment

Food containing high amount of starch: weighing 10-20 g of sample, placing the sample in a 250mL volumetric flask, adding 200mL of water, heating in a water bath at 45 ℃ for 1h, shaking constantly, cooling, adding water to the scale, mixing uniformly, and standing. And (3) sucking 200mL of supernatant into another 250mL volumetric flask, adding 5mL of zinc acetate solution and 5mL of 10.6% ferrous potassium hydride solution, adding water to the scale, uniformly mixing, standing for 30min, filtering by using dry filter paper, removing primary filtrate, and reserving the filtrate for later use.

② determination of total sugar

a. Sucking 2 parts of 50mL sample treatment solution into a 100mL volumetric flask, adding 5mL of 6mol/L hydrochloric acid into 1 part of the sample treatment solution, heating the sample treatment solution in a water bath at 68-70 ℃ for 15min, cooling the solution, adding 2 drops of methyl red indicator, neutralizing the solution to be neutral by using 20% sodium hydroxide solution, adding water to be calibrated, and uniformly mixing. The other portion was diluted to 100mL with water directly.

b. And (3) sample solution determination: 5.0mL of alkaline copper tartrate solution A and 5.0mL of solution B are sucked, placed in a 150mL conical flask, 10mL of water is added, 2 glass beads are added, a sample solution with the volume less than the predicted volume is added into a burette, the sample solution is heated to boil within 2min, titration is carried out at the speed of 1 drop per 2 seconds until the color of the solution just fades, and the consumed volume of the sample is recorded. The same procedure was followed in parallel with 3 portions to obtain the average consumption volume.

Thirdly, calculating the result:

in the formula:

m₁-10 mL of basic copper tartrate in direct titration corresponds to the amount of invert sugar, mg;

m₂-sample mass, g;

m-total weight of product, g;

y-total weight of buckwheat hulls, g;

V₁total volume of sample treatment fluid, m L;

V₂determination of the total sugar volume in hydrolysate, mL.

(2) Detection of fat

And detecting the fat content in the kitchen waste by adopting an acid hydrolysis method.

Precisely weighing about 2.0g of sample, placing the sample in a 50mL large test tube, adding 8mL of water, uniformly mixing, and then adding 10mL of hydrochloric acid.

Secondly, the test tube is placed in a water bath at the temperature of 70-80 ℃, and the glass rod is used for stirring once every 5-10 min until the sample is completely digested, wherein the time is about 40-50 min.

③ taking out the test tube, adding 10mL of ethanol, and mixing. After cooling, the mixture was transferred to a 100mL stoppered graduated cylinder, and the tube was washed with 25mL portions of ether and poured into the graduated cylinder. After the ether is poured into the measuring cylinder, adding the plug, shaking for 1min, carefully opening the plug, discharging gas, plugging again, standing for 12min, carefully opening the plug, and washing the plug and the fat attached to the cylinder mouth with petroleum ether-ether equivalent mixed solution. Standing for 10-20 min, sucking supernatant liquid out of a constant conical flask when the upper liquid is clear, adding 5mL of diethyl ether into a measuring cylinder with a plug, shaking, standing, sucking the upper diethyl ether out of the conical flask, and putting the conical flask into the original conical flask. And (3) drying the erlenmeyer flask by evaporation on a water bath, drying the erlenmeyer flask in an oven at the temperature of 95-105 ℃ for 2 hours, taking out the erlenmeyer flask, cooling the erlenmeyer flask in a drier for 0.5 hour, and weighing the erlenmeyer flask.

Fourthly, calculating a result:

in the formula:

m₁-receiving the mass of bottles and fat, g;

m₀-receiving the mass of the bottle, g;

m₃-mass of sample, g;

m-total weight of product, g;

y-buckwheat hull weight, g.

(3) Detection of proteins

And (3) detecting the protein content in the kitchen waste by adopting a Kjeldahl method.

Precisely weighing 0.2-2.0 g of solid sample or 2-5 g of semisolid sample or sucking 10-20 mL of liquid sample (about equal to 30-40 mg of nitrogen), transferring into a dry 100mL or 500mL nitrogen fixing bottle, adding 0.2g of copper sulfate, 3g of potassium sulfate and 20mL of sulfuric acid, carefully heating, after the content is completely carbonized and the foam is completely stopped, enhancing the firepower, and keeping the liquid in the bottle slightly boiling until the liquid is blue-green, clear and transparent. Taking down, cooling, transferring into a 100mL volumetric flask, adding water to the scale, and mixing uniformly for later use. Taking copper sulfate, potassium sulfate and sulfuric acid with the same amount as the treated sample, and carrying out a reagent blank test by the same method.

Secondly, a nitrogen determination device is arranged, a plurality of drops of methyl red indicating liquid and a plurality of milliliters of sulfuric acid are added to the water vapor generation bottle when the water is filled to about 2/3 positions so as to keep the water acidic, a plurality of glass beads are added to prevent bumping, and the water in the water vapor generation bottle is heated and boiled under the control of a pressure regulator.

Thirdly, adding 10mL of 2% boric acid solution and 1 drop of mixed indicating solution into the receiving bottle, inserting the lower end of the condensing tube below the liquid level, sucking 10.0mL of sample digestion diluent, flowing the sample digestion diluent into the reaction chamber from the small glass cup, taking down the receiving bottle after the reaction is finished, and titrating the sample digestion diluent to blue-violet with 0.05N hydrochloric acid standard solution. Simultaneously, 10.0mL of reagent blank digestive juice is sucked and carried out again according to the operation.

Fourthly, calculating a result:

in the formula:

V₁-volume of sample depleted sulfuric or hydrochloric acid standard, mL;

V₂-reagent blank consumption volume of sulfuric or hydrochloric acid standard solution, mL;

the equivalent concentration of the N-sulfuric acid or hydrochloric acid standard solution;

m₃-mass of sample, g;

m-total weight of product, g;

y-buckwheat hull weight, g.

1mL of 0.014-1N sulfuric acid or hydrochloric acid standard solution is equivalent to gram of nitrogen;

m-mass of sample, g;

the F-nitrogen conversion coefficient was 6.25.

(4) Sustained release property

The slow release performance of the substance is detected according to GB/T23348-2009.

The results are shown in Table 1.

Table 1:

	untreated kitchen waste	Compost obtained in example 1
			Total sugar content (%)	4.51	1.29
Fat content (%)	7.52	4.07
			Protein content (%)	11.64	5.84

Table 2:

	24h sustained release amount (%)	28d sustained Release amount (%)
			Example 1	4.37	67.36
Example 2	4.11	64.31
			Example 3	4.61	68.11
Example 4	4.16	65.40
			Example 5	4.12	65.31
Comparative example 3	24.3	99.70

As can be seen from Table 1, after the kitchen waste is subjected to composting treatment by the compound microbial agent, the total sugar content in the kitchen waste is reduced by 71.40%, the fat content is reduced by 45.88%, the protein content is reduced by 49.83%, and the compound microbial agent has a high degradation rate on organic matters in the kitchen waste.

As can be seen from the table 2, the modified bentonite is added in the preparation process, so that the slow release performance of the culture soil can be effectively improved, and the culture soil has the advantages of good slow release performance, small smell, rich organic nutrient substances and the like. The kitchen waste is recycled, the municipal solid waste treatment difficulty is greatly reduced, and the prepared slow-release culture soil can meet the requirements of the industry and has a good application prospect.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. The slow-release cultivation soil prepared based on the kitchen waste is characterized by comprising the following raw materials in parts by weight: 30-45 parts of kitchen waste, 0.5-1 part of compound microbial agent, 50-100 parts of buckwheat hulls, 3-10 parts of urea, 3-10 parts of potassium sulfate, 3-10 parts of calcium superphosphate, 80-120 parts of modified bentonite, 10-20 parts of ground phosphate rock and 15-30 parts of perlite.

2. The slow-release type culture soil prepared based on kitchen waste according to claim 1, characterized in that the preparation method of the slow-release type culture soil comprises the following steps:

3. The slow-release type culture soil prepared based on kitchen waste according to claim 2, characterized in that in step (2), the composting reactor is ventilated for 30-60 minutes every 4-4.5 hours during composting.

4. The slow-release type culture soil prepared based on kitchen waste according to claim 2, characterized in that the particle diameter of the slow-release type culture soil in step (6) is controlled to be 2-5 mm.

5. The slow-release type culture soil prepared based on kitchen waste according to claim 1 or 2, characterized in that: the total viable bacteria concentration of the compound microbial agent is (2-3) multiplied by 10¹¹cfu/g, the composite microbial agent is prepared by mixing thermophilic bacillus, candida lipolytica, aspergillus oryzae, bacillus licheniformis, trichoderma viride and azotobacter chroococcum with the viable bacteria number ratio of 1:1.5:1 (1-1.5) to 2: 1.

6. The slow-release type aquaculture soil prepared based on kitchen waste according to claim 1, characterized in that the preparation method of the modified bentonite comprises the following steps:

7. The slow-release type culture soil prepared based on kitchen waste according to claim 6, characterized in that: in the step (1), bentonite and Na₂CO₃The mass ratio to water is 25: 1: (120-140).

8. The slow-release type culture soil prepared based on kitchen waste according to claim 6, characterized in that: and (3) drying and crushing the paste in the step (2) at the temperature of 100 ℃ and 120 ℃, and sieving the dried and crushed paste with a 230-270-mesh sieve.

9. The slow-release type aquaculture soil prepared based on kitchen waste according to claim 6, characterized in that the mass ratio of polyvinylpyrrolidone to water to powdered bentonite in step (3) is 1 (5-9) to 1.

10. The slow-release type culture soil prepared based on kitchen waste according to claim 6, characterized in that: and (4) performing ultrasonic dispersion for 50-70min at the ultrasonic power of 100-.