Method for rapidly preparing amino acid organic fertilizer by using agricultural and forestry wastes

Abstract

A method for rapidly preparing amino acid organic fertilizer by using agricultural and forestry wastes, comprising the following steps: 1) preparing agricultural and forestry waste digestion solution; 2) neutralizing and detoxifying; 3) fermenting; 4) hydrolyzing autolysis; and 5) finishing. The present application uses cheap agricultural and forestry wastes such as wood chips and straw chips to prepare organic compost, which is combined with inorganic nitrogen source to be converted into protein, and then is hydrolyzed into organic fertilizer amino acid by using the autolysis property of microorganisms, and is more easily absorbed. The organic fertilizer not only provides ammonia nitrogen in the form of amino acid, but also can improve the survival environment of soil microorganisms, improve soil structure, improve soil fertility, greatly improve product quality, and can be widely popularized.

Description

Technical Field

[0001] This invention relates to the field of fertilizer production technology, and in particular to a method for rapidly preparing amino acid organic fertilizer using agricultural and forestry waste. Background Technology

[0002] Organic fertilizers can effectively improve the utilization rate of chemical fertilizers, decompose pesticide residues, improve crop quality, produce pollution-free food, and reduce the harm to humans and animals caused by excessive application of chemical fertilizers. On the other hand, the inorganic and organic nutrients contained in organic fertilizers can directly provide nutrition to crops, which is conducive to crop absorption and quality improvement, enhances the activity of soil microorganisms, accelerates the decomposition of soil organic matter and the transformation of mineral nutrients, thereby strengthening the absorption of nutrients by crop roots and enhancing the plant's ability to resist diseases and pests.

[0003] In recent years, amino acid bio-organic fertilizer has become a popular new type of fertilizer in the fertilizer industry, showing excellent performance in application. It contains organic matter rich in ammonia nitrogen. As a new type of fertilizer that has been promoted and applied in recent years, amino acid organic fertilizer is widely used in agricultural planting due to its low production cost, complete nutrient elements, and unique microorganisms that can effectively improve the soil environment, increase the utilization rate of chemical fertilizers, and are relatively environmentally friendly and safe. Organic fertilizer can improve soil, enhance soil fertility, and restore the normal ecological balance of the soil. Organic compost containing cow manure can better increase the soil organic matter content, form granular structure, and improve soil aeration, water retention, and fertilizer retention, thereby benefiting crop root growth and improving plant quality and yield. Applying bio-organic fertilizer not only provides the nutrients needed for crop production, but also has the advantages of regulating soil microbial ecology, improving soil, and increasing yield and quality. It can improve crop quality, enhance plant resistance, and reduce the incidence of soil-borne diseases. However, the high cost and long manufacturing cycle of amino acid bio-organic fertilizer are key issues hindering the healthy development of the industry, and there is relatively little research on its inexpensive preparation.

[0004] Generally, the fermentation of organic fertilizer takes 7 to 60 days. Natural anaerobic fermentation typically takes two months, resulting in high land costs; while aerobic fermentation generally takes more than 7 days, with higher costs for ventilation and electricity. Therefore, rapid fermentation is an important development direction for organic fertilizer technology. Summary of the Invention

[0005] The purpose of this invention is to solve the above-mentioned problems in the prior art and to provide a method for rapidly preparing amino acid organic fertilizer using agricultural and forestry waste.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste includes the following steps:

[0008] (1) Preparation of digestion liquid from agricultural and forestry waste

[0009] Agricultural and forestry waste is dried to a moisture content of less than 30%, and then crushed into powder with a particle size of less than 1 cm to obtain waste powder. According to the weight ratio, 1 part of agricultural and forestry waste waste powder is added to 1-50 parts of acid solution, the temperature is maintained at 30-240℃, and the mixture is stirred appropriately for 1-2000 min to obtain digestive liquid, the main components of which are glucose and xylose.

[0010] The agricultural and forestry waste includes crop straw, husks, garden waste, etc., and its main components are cellulose and hemicellulose.

[0011] The acid solution is an aqueous solution with a concentration of 0.1% to 20% (w / v), and the acid is an acidic substance with an acidity coefficient pKa value of less than -1.7 at 25°C, including but not limited to at least one of hydroiodic acid, hydrobromic acid, and perchloric acid.

[0012] (2) Neutralization and detoxification

[0013] Gradually add the neutralizing agent to the digestive fluid while stirring, until the pH value rises to above 5.0, removing toxic substances such as aldehydes, acids, and phenols that affect fermentation.

[0014] Neutralizing agents include at least one of the following: ammonia water, liquid ammonia, ammonia gas, ammonium bicarbonate, urea, ammonium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, sodium bicarbonate, calcium oxide, and calcium hydroxide.

[0015] (3) Fermentation

[0016] Mix one part of the inoculum powder with the neutralized digestion solution at an inoculation ratio of 1:5 to 100,000. Aerate the mixture at a rate of 0.1 to 100 L / L. -1 Solution·min -1 Ferment at 25–37°C for 4–72 hours to obtain crude protein solution.

[0017] The international unit for fermenter aeration is vvm, expressed as air volume / culture volume / min. It is the ratio of aeration rate per minute to the actual volume of the fermentation liquid in the tank. The gas volume is measured under standard conditions, and its unit is cubic meters per (cubic meters * minutes). Aeration ratio = aeration rate (unit: cubic meters / minute) / fermentation liquid volume (unit: cubic meters).

[0018] The strain is a mixture of one or more fungal or bacterial species. It is characterized by being a non-toxic probiotic that can ferment glucose or xylose and inorganic ammonia nitrogen to produce single-cell proteins. Fungi include *Saccharomyces cerevisiae*, *Pichia pastoris*, *Candida utilis*, *Candida parapsilosis*, *Candida tropicalis*, *D. hansenli*, *T. cutaneum*, *G. candidum*, and *A. niger*, while bacteria include *Bacillus subtilis*, *Lactobacillus*, *Acetobacter*, *Corynebacterium*, *Bacillus brevis*, and *Pseudomonas*.

[0019] (4) Hydrolysis and autolysis

[0020] Adjust the pH to 4–6, and the electrolyte ion concentration to 0.0001%–3.0% (w / v, one or more of zinc, iron, copper, sodium, potassium, calcium, and magnesium salts). Maintain a high temperature of 40–70℃ for 1–80 hours to induce autolysis of the bacterial cells. Utilize the dissolved proteases to hydrolyze single-cell proteins, obtaining an amino acid water-soluble fertilizer mother liquor. The amino nitrogen concentration in the mother liquor is generally not less than 5.0 g / L. If the protease activity is insufficient, hydrolysis can be promoted by adding proteases at a concentration of 0.1–3000 IU / L.

[0021] (5) Organize

[0022] The mother liquor is treated by means of filtration, centrifugation, evaporation, etc., to further obtain amino acid liquid fertilizer or amino acid solid fertilizer, and the mass fraction of total nutrients is not lower than the level specified in the agricultural industry standard of the People's Republic of China NYT 525-2021.

[0023] Compared with the prior art, the beneficial effects achieved by the technical solution of this invention are:

[0024] 1) This invention uses inexpensive agricultural and forestry waste such as sawdust and straw to produce organic compost. This compost combines inorganic nitrogen sources with proteins, which are then hydrolyzed into amino acids using the autolytic properties of microorganisms, making it easier to absorb. This organic fertilizer not only provides ammonia nitrogen in the form of amino acids but also improves the living environment of soil microorganisms, modifies soil structure, enhances soil fertility, greatly improves product quality, and is suitable for large-scale promotion.

[0025] 2) By using chemical catalysis technology, the lignocellulose in agricultural and forestry waste is rapidly degraded into monosaccharides that are easily utilized by microorganisms, which greatly shortens the hydrolysis time.

[0026] 3) Change the long-cycle solid-state composting fermentation technology and use liquid ventilation technology to quickly ferment and obtain a large amount of single-cell protein.

[0027] 4) By changing the conditions, microbial autolysis is initiated, and the proteases carried by the microorganisms hydrolyze single-cell proteins into amino acids. Detailed Implementation

[0028] To make the technical problems, technical solutions and beneficial effects of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the embodiments.

[0029] This invention prepares an amino acid-based microbial organic fertilizer, comprising the following steps:

[0030] (1) Preparation of digestion liquid from agricultural and forestry waste

[0031] Agricultural and forestry waste is dried to a moisture content of less than 30%, and then crushed into powder with a particle size of less than 1 cm to obtain waste powder. According to the weight ratio, 1 part of agricultural and forestry waste waste powder is added to 1-50 parts of acid solution, the temperature is maintained at 30-240℃, and the mixture is stirred appropriately for 1-2000 min to obtain digestive liquid, the main components of which are glucose and xylose.

[0032] The agricultural and forestry waste includes crop straw, husks, garden waste, etc., and its main components are cellulose and hemicellulose.

[0033] The acid solution is an aqueous solution with a concentration of 0.1% to 20% (w / v), and the acid is an acidic substance with an acidity coefficient pKa value of less than -1.7 at 25°C, including but not limited to at least one of hydroiodic acid, hydrobromic acid, and perchloric acid.

[0034] (2) Neutralization and detoxification

[0035] Gradually add the neutralizing agent to the digestive fluid while stirring, until the pH value rises to above 5.0, removing toxic substances such as aldehydes, acids, and phenols that affect fermentation.

[0036] Neutralizing agents include at least one of the following: ammonia water, liquid ammonia, ammonia gas, ammonium bicarbonate, urea, ammonium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, sodium bicarbonate, calcium oxide, and calcium hydroxide.

[0037] (3) Fermentation

[0038] Mix one part of the inoculum powder with the neutralized digestion solution at an inoculation ratio of 1:5 to 100,000. Aerate the mixture at a rate of 0.1 to 100 L / L. -1 Solution·min -1 Ferment at 25–37°C for 4–72 hours to obtain crude protein solution.

[0039] The strain is a mixture of one or more fungal or bacterial species. It is characterized by being a non-toxic probiotic that can ferment glucose or xylose and inorganic ammonia nitrogen to produce single-cell protein. Fungi include *Saccharomyces cerevisiae*, *Pichia pastoris*, *Candida utilis*, *Candida parapsilosis*, *Candida tropicalis*, *D. hansenli*, *T. cutaneum*, *G. candidum*, and *A. niger*, etc.; bacteria include *Bacillus subtilis*, *Lactobacillus*, *Acetobacter*, *Corynebacterium*, *Bacillus brevis*, *Pseudomonas*, etc.

[0040] (4) Hydrolysis and autolysis

[0041] Adjust the pH to 4–6, and the ion concentration to 0.0001%–3.0% (w / v, one or more of zinc, iron, copper, sodium, potassium, calcium, and magnesium salt electrolytes). Maintain a high temperature of 40–70℃ for 1–80 hours to induce autolysis of the bacterial cells. The released proteases then promote the hydrolysis of single-cell proteins, yielding an amino acid water-soluble fertilizer mother liquor. The amino nitrogen concentration in the mother liquor is generally not less than 5.0 g / L. If the protease activity is insufficient, hydrolysis can be promoted by adding proteases at a concentration of 0.1–3000 IU / L.

[0042] (5) Organize

[0043] The mother liquor is treated by means of filtration, centrifugation, evaporation, etc., to further obtain amino acid liquid fertilizer or amino acid solid fertilizer, and the mass fraction of total nutrients is not lower than the level specified in the agricultural industry standard of the People's Republic of China NYT 525-2021.

[0044] Example 1

[0045] This embodiment prepares an amino acid-based microbial organic fertilizer using the following steps:

[0046] (1) Preparation of digestion liquid from agricultural and forestry waste

[0047] The corn stalks were dried to a moisture content of 10%, and then crushed into powder with a particle size of less than 1 cm to obtain a powder. One part of the powder was added to 10 parts of a 5% hydrobromic acid solution by weight, and the temperature was kept at 130℃. The solution was stirred moderately for 60 minutes to obtain a digestive liquid, the main components of which were glucose and xylose.

[0048] (2) Neutralization and detoxification

[0049] Ammonia and calcium oxide neutralizer are gradually added to the digestion liquid in a weight ratio of 4:1. The mixture is stirred while adding the ammonia and calcium oxide until the pH value rises to above 6.0, thus removing toxic substances such as aldehydes, acids, and phenols that affect fermentation.

[0050] (3) Fermentation

[0051] Mix one part of Saccharomyces cerevisiae inoculum powder with the neutralized digestion solution at an inoculation ratio of 1:10000. Aeration is introduced at a rate of 1.0 L / L. -1 Solution·min -1 Fermented at 30℃ for 24 hours, then inoculated with Bacillus subtilis inoculum powder at a ratio of 1:5000, and fermented again at 37℃ for 24 hours with an aeration rate of 1.0 L·L⁻¹. -1 Solution·min -1 A crude protein solution was obtained.

[0052] (4) Hydrolysis and autolysis

[0053] The pH was adjusted to 5, the zinc ion concentration was 0.001% (w / v), the sodium ion concentration was 2.0% (w / v), and 1.0 IU / L of papain was added. The mixture was kept at 60℃ for 10 hours to induce cell autolysis. The released protease was then used to hydrolyze single-cell proteins, yielding an amino acid-soluble organic fertilizer mother liquor. Tests showed that the amino nitrogen concentration in the mother liquor was not less than 5.0 g / L.

[0054] (5) Organize

[0055] The mother liquor was treated by filtration, centrifugation, and evaporation to obtain amino acid liquid fertilizer with an amino nitrogen content of 5% and a total nutrient content exceeding the level specified in the People's Republic of China Agricultural Industry Standard NYT 525-2021.

[0056] Example 2

[0057] This embodiment prepares an amino acid-based microbial organic fertilizer using the following steps:

[0058] (1) Preparation of digestion liquid from agricultural and forestry waste

[0059] Pine wood chips are dried to a moisture content of 11%, then pulverized into powder with a particle size of less than 1 cm to obtain wood chip powder. One part of the wood chip powder is added to 15 parts of a 4% perchloric acid solution, the temperature is maintained at 120℃, and the solution is stirred moderately for 50 minutes to obtain a digestive liquid, the main components of which are glucose and xylose.

[0060] (2) Neutralization and detoxification

[0061] Gradually add ammonium bicarbonate and calcium hydroxide neutralizing agent to the digestion liquid in a 1:1 weight ratio, stirring constantly as you add, until the pH value rises to above 6.0, thus removing toxic substances such as aldehydes, acids, and phenols that affect fermentation.

[0062] (3) Fermentation

[0063] Mix one part of *Candida utilis* inoculum powder with the neutralized digestion solution at an inoculation ratio of 1:5000. Aeration is introduced at a rate of 2.0 L / L. -1 Solution·min -1 Fermented at 28℃ for 20 hours, then inoculated with Bacillus subtilis inoculum powder at a ratio of 1:3000, and fermented for another 28 hours at 37℃ with an aeration rate of 2.0 L·L⁻¹. -1 Solution·min -1 A crude protein solution was obtained.

[0064] (4) Hydrolysis and autolysis

[0065] The pH was adjusted to 4.5, the copper ion concentration was 0.001% (w / v), and the sodium ion concentration was 1.5% (w / v). 1.0 IU / L of Bacillus subtilis protease was added, and the mixture was kept at 65℃ for 8 hours to induce cell autolysis. The dissolved protease was then used to hydrolyze single-cell proteins, yielding an amino acid-soluble organic fertilizer mother liquor. Testing revealed that the amino nitrogen concentration in the mother liquor was not less than 6.0 g / L.

[0066] (5) Organize

[0067] The mother liquor was treated by filtration, centrifugation, and evaporation to obtain amino acid liquid fertilizer with an amino nitrogen content of 6% and a total nutrient mass fraction that is higher than the level specified in the People's Republic of China Agricultural Industry Standard NYT 525-2021.

[0068] This invention utilizes inexpensive agricultural and forestry waste such as sawdust and straw to produce organic compost. This compost combines inorganic nitrogen sources with proteins, which are then hydrolyzed into amino acids using the autolytic properties of microorganisms, making it easier to absorb. This organic fertilizer not only provides ammonia nitrogen in the form of amino acids but also improves the living environment of soil microorganisms, modifies soil structure, enhances soil fertility, significantly improves product quality, and is suitable for large-scale promotion.

Claims

1. A method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste, characterized in that, Includes the following steps: 1) Preparation of digestion liquid for agricultural and forestry waste: Agricultural and forestry waste is crushed into powder to obtain shavings powder. The shavings powder is added to an acid solution and stirred to obtain digestion liquid; 2) Neutralization and detoxification: Add a neutralizing agent to the digestive fluid while stirring until the pH value rises to ≥5.0; 3) Fermentation: Mix the inoculum powder with the neutralized digestive liquid, introduce air for fermentation, and obtain a crude protein solution; 4) Hydrolysis and autolysis: Adjust the pH to 4-6, and the mass concentration of electrolyte ions to 0.0001%-3.0%. Maintain the temperature at 40-70℃ for 1-80 h to promote autolysis of bacterial cells. Use the dissolved protease to promote the hydrolysis of single-cell proteins to obtain an amino acid water-soluble fertilizer mother liquor. The amino nitrogen concentration in the mother liquor should not be less than 5.0 g / L. If the protease activity is insufficient, add protease to promote hydrolysis. The amount added is 0.1-3000 IU / L. 5) Processing: The mother liquor is treated by means of filtration, centrifugation, evaporation, etc., to further obtain amino acid liquid fertilizer or amino acid solid fertilizer, with a total nutrient mass fraction ≥4%; In step 1), the particle size of the powder is ≤1.0 cm; the mass ratio of the powder to the acid solution is 1:1~50 by weight. In step 1), the acid solution is an aqueous solution with a mass concentration of 0.1% to 20%, and the type of acid is one with an acidity coefficient p at 25°C. K Acidic substances with an a value ≤ -1.7 include at least one of hydroiodic acid, hydrobromic acid, and perchloric acid.

2. The method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste as described in claim 1, characterized in that: The agricultural and forestry waste includes crop straw, husks, and garden waste, and its main components are cellulose and hemicellulose.

3. A method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste as described in claim 1, characterized in that: In step 1), the stirring process is carried out at a temperature of 30~240℃ for 1~2000 min.

4. The method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste as described in claim 1, characterized in that: In step 2), the neutralizing agent includes at least one of ammonia water, liquid ammonia, ammonia gas, ammonium bicarbonate, urea, ammonium carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, sodium bicarbonate, calcium oxide, and calcium hydroxide.

5. A method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste as described in claim 1, characterized in that: In step 3), the inoculation ratio of inoculum powder to digestion liquid is 1:5 to 100,000 by mass; the air ventilation rate is 0.1 to 100 L / L. -1 Solution·min -1 The fermentation conditions are 25~37℃ for 4~72 h.

6. The method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste as described in claim 1, characterized in that: In step 3), the strain is a mixture of one or more fungal or bacterial strains. This strain is a non-toxic probiotic that can ferment glucose or xylose and inorganic ammonia nitrogen to produce single-cell protein.

7. A method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste as described in claim 6, characterized in that: The fungi include Saccharomyces cerevisiae (Saccharomyces cerevisiae) S. cerevisiae Pichia pastoris () Pichiapastoris ), Candida utilis ( C. utilis ), Candida parapsilosis ( C. parapsilosis ), Tropical Candida ( C. tropicalis ), Hansenbali yeast ( D. hansenli ), dermal filamentous yeast ( T. cutaneum ), white ground mold ( G. candidum ) and Aspergillus niger ( A. niger The bacteria include Bacillus subtilis ( ); Bacillus subtilis ), Lactobacillus ( Lactobacillus Acetic acid bacteria ( Acetobacter ), Corynebacterium ( Corynebacterium ), Bacillus pumilus ( Bacillus brevis ), Pseudomonas ( Pseudomonas ).

8. The method for rapidly preparing amino acid organic fertilizer from agricultural and forestry waste as described in claim 1, characterized in that: In step 4), the electrolyte is one or more of zinc, iron, copper, sodium, potassium, calcium, and magnesium salt electrolytes.