Composite bio-organic fertilizer as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of waste converted fertilizers. The invention provides a composite bio-organic fertilizer as well as a preparation method and application thereof, and the composite bio-organic fertilizer comprises the following components in parts by weight: 95-100 parts of a honeysuckle residue fermentation product, 31-33 parts of calcium oxide, 8-9 parts of struvite and 5-7 parts of nitrogen-doped biochar, the honeysuckle residue fermentation product is prepared by fermenting honeysuckle residues through a complex microbial inoculant, and the complex microbial inoculant comprises chaetomium thermophile, sporotrichum thermophile, paenibacillus polymyxa, bacillus mucilaginosus and candida utilis. The total content of nitrogen, phosphorus and potassium and the long-term fertilizer efficiency performance of the prepared composite bio-organic fertilizer can be improved, and it is ensured that the composite bio-organic fertilizer has the remarkable yield increasing effect on cucumber planting.

Description

Technical Field

[0001] The invention belongs to the technical field of waste conversion fertilizer, and in particular relates to a composite bio-organic fertilizer and a preparation method and application thereof. Background Art

[0002] As an environmentally friendly resource, the production and widespread application of bio-organic fertilizers are straightforward: the raw materials are readily available, they contribute to soil optimization, and they offer significant environmental benefits and significant economic benefits. Using waste materials such as traditional Chinese medicine residues, straw, and livestock manure as raw materials, bio-organic fertilizers can be used to meet the growing needs of various crops, with significant economic and ecological significance for social development. For example, cucumbers have a high demand for potassium throughout their growth cycle, followed by nitrogen, with phosphorus absorption increasing dramatically during the reproductive phase. This means that cucumbers have a long-term demand for nitrogen, phosphorus, and potassium throughout their growth.

[0003] In the prior art, waste honeysuckle residue after extraction from honeysuckle dew is recycled to produce organic fertilizer. When calcium oxide is used as a dewatering agent, the higher the amount of calcium oxide used, the lower the water content of the honeysuckle residue and, consequently, the lower the nitrogen, phosphorus, and potassium content of the produced organic fertilizer. To ensure that both the water content of the honeysuckle residue and the nitrogen, phosphorus, and potassium content of the organic fertilizer meet national standards, the amount of calcium oxide used is set at 35-38% of the amount of the honeysuckle residue. This allows calcium oxide, as a dewatering agent, to meet national standards for organic fertilizer.

[0004] However, the use of calcium oxide causes calcium ions to combine with phosphates to form insoluble calcium phosphate precipitates, reducing the effective phosphorus content; calcium oxide absorbs water and is alkaline, and the alkaline environment promotes the conversion of ammonium nitrogen into ammonia volatilization, resulting in nitrogen loss; under alkaline conditions, the solubility of potassium salts decreases and is lost through leaching; ultimately, the total content of nitrogen, phosphorus, and potassium and long-term fertilizer efficiency are reduced, which is not conducive to increasing cucumber production. Summary of the Invention

[0005] In response to the above problems, the present invention proposes a composite bio-organic fertilizer and its preparation method and application, which can improve the total nitrogen, phosphorus and potassium content and long-term fertilizer efficiency of the prepared composite bio-organic fertilizer, ensuring that it has a significant yield-increasing effect on cucumber cultivation.

[0006] In order to achieve the above-mentioned objectives, in a first aspect, the present invention provides a composite biological organic fertilizer, comprising components, by weight: 95-100 parts of honeysuckle residue fermentation product, 31-33 parts of calcium oxide, 8-9 parts of struvite and 5-7 parts of nitrogen-doped biochar; the honeysuckle residue fermentation product is prepared by fermenting honeysuckle residue with a composite bacterial agent, and the composite bacterial agent includes thermophilic Chaetomium, thermophilic Sporotrichum, polymyxa Bacillus, jelly-like Bacillus and utilis.

[0007] Furthermore, the mass of the composite bacterial agent is 0.3%-0.5% of the mass of the honeysuckle residue; Thermophilic Chaetomium: 0.8×10 9 -1.5×10 9 CFU / g; Thermospora: 0.6×10 9 -1.0×10 9 CFU / g; Paenibacillus polymyxa: 5.0×10 8 -8.0×10 8 CFU / g; Bacillus jelly: 5.0×10 8 -8.0×10 8 CFU / g; Candida utilis: 2.0×10 8 -5.0×10 8 CFU / g.

[0008] Furthermore, the fermentation time is 15-20 days, the humidity is controlled at 50%-60%, and the temperature is 55-65°C.

[0009] Furthermore, the preparation method of the nitrogen-doped biochar is as follows:

[0010] A1. Mixing thiourea and biochar and grinding them thoroughly to obtain a mixture;

[0011] A2. Under nitrogen protection, the mixture obtained in A1 was placed in a tube furnace for high-temperature pyrolysis to obtain a pyrolyzate;

[0012] A3. Grind the pyrolyzate obtained in A2, rinse with deionized water, and then dry in an oven to obtain nitrogen-doped biochar.

[0013] Furthermore, in A1, the mass ratio of thiourea to biochar is (1-1.5):1.

[0014] Furthermore, in A2, the specific operation of high-temperature pyrolysis is: heating rate of 5-10°C / min, heating to 800-820°C, and keeping warm for 2-2.5h.

[0015] Furthermore, in A3, the mixture is rinsed with deionized water for 3-5 times until the pH of the filtrate is 6.8-7.2.

[0016] Furthermore, in A3, the drying temperature is 60±5°C and the drying time is 10-12h.

[0017] In a second aspect, the present invention provides a method for preparing the above-mentioned composite bio-organic fertilizer, comprising the following steps:

[0018] S1. Put the fermented product of honeysuckle residue, calcium oxide, struvite and nitrogen-doped biochar into a blender at a speed of 28-32 r / min and mix for 25-35 min to obtain a mixture;

[0019] S2. Place the mixed material obtained in S1 into a pile and cover it with a breathable film. Turn the pile over once every 2-3 days at a temperature of 50-60°C. After 8-10 days, obtain a matured material.

[0020] S3, drying and granulating the matured material obtained in S2 to obtain the composite bio-organic fertilizer.

[0021] In a third aspect, the present invention provides an application of the above-mentioned composite bio-organic fertilizer for cucumber cultivation.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] In the preparation of the composite bio-organic fertilizer of the present invention, struvite and nitrogen-doped biochar are introduced on the basis of raw materials, namely, fermentation product of honeysuckle residue and calcium oxide.

[0024] On the one hand, nitrogen-doped biochar itself significantly improves its Ca absorption capacity by introducing nitrogen-containing functional groups and expanding its micropore structure. 2 + NH 4+ and K + The specific surface area of ​​nitrogen-doped biochar is higher than that of ordinary biochar, which can directly fix the Ca released by calcium oxide. 2+ , reducing the formation of calcium phosphate precipitation and improving the effective phosphorus retention rate; the surface acidic groups (-COOH) of nitrogen-doped biochar react with the OH groups generated by the hydrolysis of calcium oxide - reaction, lowering the local pH and inhibiting the NH 4+ The conversion to NH3 reduces the nitrogen volatilization loss rate.

[0025] On the other hand, the surface functional groups of nitrogen-doped biochar -NH2 preferentially adsorb Ca through electrostatic interaction. 2+ , reducing free Ca in the solution 2+ concentration, thereby inhibiting the PO4 released by the decomposition of struvite 3- With Ca 2+ The tendency to form calcium phosphate precipitates; unreacted Mg 2+ With PO4 3- The combined magnesium phosphate can be wrapped by the micropores of biochar to form a slow-release structure; the oxygen-containing functional groups on the surface of nitrogen-doped biochar can also form hydrogen bonds with NH3, reducing the escape rate of gaseous nitrogen, thereby synergistically improving long-term fertilizer efficiency.

[0026] Nitrogen-doped biochar can also replace part of the water removal demand of calcium oxide by storing water in the pores, reducing the demand for calcium oxide and thus reducing excess Ca 2+ Input risk; Aromatized carbon layers of nitrogen-doped biochar immobilize K via π-π electron interactions +, increasing the adsorption capacity of potassium ions, while the Mg released by struvite 2+ With K + Compete for adsorption sites, forcing K + It migrates to the surface of biochar and forms a stable complex (KOC) with the oxygen-containing groups on the surface, reducing potassium leaching, thereby synergistically improving long-term fertilizer efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a comparative trend chart of per-acre yield of cucumbers obtained by using the composite bio-organic fertilizers prepared in Examples 1 to 3 and Comparative Examples 1 to 4 in the test examples of the present invention;

[0028] Figure 2 The graph is a comparison trend of the yield growth rate of cucumber cultivation using the composite bio-organic fertilizers prepared in Examples 1 to 3 and Comparative Examples 1 to 4 in the test examples of the present invention. DETAILED DESCRIPTION

[0029] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] Example 1

[0031] 1. Preparation of honeysuckle residue fermentation product, the preparation method is as follows: crush the honeysuckle residue to a particle size of less than 5mm, increase the specific surface area of ​​the material, promote microbial contact and decomposition efficiency (121℃ high temperature steam treatment for 15min to avoid fermentation contamination), and then mix with the composite bacterial agent. Add the composite bacterial agent at 0.4% of the residue mass, and spray the bacterial suspension evenly during mixing. The composite bacterial agent includes thermophilic Chaetomium, thermophilic Sporangium, polymyxa, jelly-like Bacillus and utilis. Thermophilic Chaetomium (1.2×10 9 CFU / g: decomposes cellulose and improves the degradation rate of materials; Thermospora spp. (0.7×10 9 CFU / g: produces extracellular enzymes, accelerating lignin degradation; Paenibacillus polymyxa (6.3×10 8 CFU / g: antibacterial, promoting plant growth; Bacillus jelly (6.5×10 8 CFU / g): releases phosphorus and potassium, improving fertilizer efficiency; Candida utilis (3.7×10 8CFU / g): Synthesizes proteins and vitamins to enrich the product's nutrition. Chaetomium thermophilum (361040) was purchased from Shanghai Xinfan Biotechnology Co., Ltd. Sporotrichum thermophilum (RN-06425) and Paenibacillus polymyxa (RN-99502) were purchased from Nuoan Gene Technology (Wuhan) Co., Ltd. Bacillus gelatinosa (XKJZ1510) was purchased from Shanghai Xuanke Biotechnology Co., Ltd. Candida utilis (P1521) was purchased from Shanghai Xuanya Biotechnology Co., Ltd.

[0032] Then fermentation is carried out, and the humidity is controlled at 50%-60%, and the temperature is 55-65℃. It is turned over once on the 3rd, 7th, 12th and 17th days. Sterile water is sprayed to replenish moisture during turning. After a total of 18 days of fermentation, the material is dark brown, loose in texture, and has no sour or rotten smell, thus obtaining the fermented honeysuckle residue.

[0033] 2. Preparation of nitrogen-doped biochar, the preparation method is as follows:

[0034] A1. Pre-crush the biochar to 300 mesh (particle size ≤ 48 μm) to increase the specific surface area and enhance doping efficiency. The moisture content of the raw material should be ≤ 8% to prevent water vapor from interfering with the nitrogen doping reaction during pyrolysis. Mix thiourea and biochar at a mass ratio of 1.2:1 and thoroughly grind using a planetary ball mill at 300 rpm for 30 minutes, ensuring a uniformity of >95% to obtain a mixture.

[0035] A2. Under nitrogen protection (nitrogen flow rate 100 mL / min, oxygen content required to be <50 ppm), the mixture obtained in A1 was placed in a tube furnace for high-temperature pyrolysis. Specifically, the temperature was increased in stages: from room temperature to 300°C at a heating rate of 5°C / min to promote the decomposition and penetration of thiourea; then from 300°C to 800°C at a heating rate of 10°C / min and maintained for 2 hours to promote graphitization and nitrogen doping to obtain a pyrolyzate. The pyrolysis of thiourea produces H2S and nitrogen-containing free radicals, which react with the biochar skeleton to form C-N bonds and sulfur-containing functional groups.

[0036] A3. Grind the pyrolyzate obtained in A2 to 400 mesh (particle size ≤ 38 μm), rinse with deionized water 4 times, and use ultrasonic assisted washing (40 kHz, 30 min / time) to improve the impurity removal efficiency. Rinse until the pH of the filtrate is about 7 to avoid excessive acid from destroying the nitrogen-doped structure. Then place it in an oven for drying at a drying temperature of 60°C and vacuum drying (-0.08 MPa) for 12 h to inhibit the formation of oxides. The water content is ≤5% to avoid agglomeration, thereby obtaining nitrogen-doped biochar.

[0037] 3. A method for preparing a composite bio-organic fertilizer, comprising the following steps:

[0038] S1. Put 98 parts of fermented honeysuckle residue, 32 parts of calcium oxide, 8.5 parts of struvite and 6 parts of nitrogen-doped biochar into a blender at a speed of 30 r / min for 30 minutes to obtain a mixture.

[0039] S2. Place the mixed material obtained in S1 into a pile and cover it with a 60-mesh non-woven breathable film. Turn the pile over once every three days at a temperature of 50-60° C. After nine days, obtain the matured material.

[0040] S3. Dry and granulate the slaked material obtained in S2 in two stages: a first stage of fluidized bed drying (80°C x 40 min) to reduce the moisture content to approximately 9%, and a second stage of vacuum drying (60°C x 2 h) to a final moisture content of 4.1%. Granulate the material using a rotary drum granulator, add 3% polyvinyl alcohol solution (8% by mass) as a binder, and control the particle size to 2-4 mm to obtain a composite bio-organic fertilizer.

[0041] The compound bio-organic fertilizer is used for cucumber cultivation.

[0042] Example 2

[0043] The difference between this embodiment and embodiment 1 is that: a method for preparing a composite bio-organic fertilizer comprises the following steps:

[0044] S1. Put 95 parts of fermented honeysuckle residue, 31 parts of calcium oxide, 8 parts of struvite and 5 parts of nitrogen-doped biochar into a blender at a speed of 28 r / min for 35 minutes to obtain a mixture.

[0045] S2. Place the mixed material obtained in S1 into a pile and cover it with a breathable film. Turn the pile over once every two days at a temperature of 50-60° C. to obtain a matured material after eight days.

[0046] S3, drying and granulating the matured material obtained in S2 to obtain a composite bio-organic fertilizer.

[0047] Example 3

[0048] The difference between this embodiment and embodiment 1 is that: a method for preparing a composite bio-organic fertilizer comprises the following steps:

[0049] S1. Put 100 parts of fermented honeysuckle residue, 33 parts of calcium oxide, 9 parts of struvite and 7 parts of nitrogen-doped biochar into a blender at a speed of 32 r / min for 25 minutes to obtain a mixture.

[0050] S2. Place the mixed material obtained in S1 into a pile and cover it with a breathable film. Turn the pile over once every three days at a temperature of 50-60° C. to obtain a matured material after 10 days.

[0051] S3, drying and granulating the matured material obtained in S2 to obtain a composite bio-organic fertilizer.

[0052] Comparative Example 1

[0053] The difference between this comparative example and Example 1 is that struvite and nitrogen-doped biochar are deleted.

[0054] Specifically, a method for preparing a composite bio-organic fertilizer comprises the following steps:

[0055] S1. Put 98 parts of fermented honeysuckle residue and 32 parts of calcium oxide into a blender at a speed of 30 r / min and mix for 30 min to obtain a mixture.

[0056] S2. Place the mixed material obtained in S1 into a pile and cover it with a 60-mesh non-woven breathable film. Turn the pile over once every three days at a temperature of 50-60° C. After nine days, obtain the matured material.

[0057] S3, drying and granulating the matured material obtained in S2 to obtain a composite bio-organic fertilizer.

[0058] Comparative Example 2

[0059] The difference between this comparative example and Example 1 is that the nitrogen-doped biochar is deleted.

[0060] Comparative Example 3

[0061] The difference between this comparative example and Example 1 is that struvite is deleted.

[0062] Comparative Example 4

[0063] The difference between this comparative example and Example 1 is that the nitrogen-doped biochar is replaced by biochar.

[0064] Test example

[0065] Test objects: Composite bio-organic fertilizers were prepared according to Examples 1 to 3 and Comparative Examples 1 to 4.

[0066] Experimental method: 8 cucumber greenhouses were selected, each covering an area of ​​approximately 0.5 mu (approximately 0.5 acres), with 4,000 cucumbers planted per acre, with a plant spacing of 25 cm and a row spacing of 60 cm. One of the greenhouses served as a control group, to which no fertilizer was applied; the other seven served as experimental groups, to which equal amounts of the compound bio-organic fertilizers prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were applied, at an application rate of 350 kg / acre. The total yield of the cucumbers was uniformly measured at the end of their fruiting period, converted to yield per acre, and the yield growth rate of each experimental group was calculated.

[0067] Calculation formula: yield growth rate = (yield per mu of the experimental group - yield per mu of the blank group) / yield per mu of the blank group × 100%.

[0068] Test results: See Table 1.

[0069] Table 1. Test case data statistics

[0070] Grouping (Group) Yield per mu (kg) Output growth rate (%) blank 4653.15 - Example 1 6424.58 38.1 Example 2 6385.28 37.2 Example 3 6398.73 37.5 Comparative Example 1 5710.83 22.7 Comparative Example 2 5758.44 23.6 Comparative Example 3 6143.22 31.9 Comparative Example 4 6160.97 32.2

[0071] Analyze Example 1-Example 3 and Comparative Example 1-Comparative Example 3, and combine the data in Table 1 and Figure 1-Figure 2 It can be seen that the composite bio-organic fertilizer prepared by the present invention (Example 1-Example 3) is used for cucumber cultivation, and the yield per mu can reach more than 6385.28 kg. Compared with the blank group without fertilization, the yield growth rate is as high as more than 37.2%.

[0072] Analyze Example 1 and Comparative Examples 1-4, and combine the data in Table 1 and Figure 1-Figure 2 Specifically, by comparing Comparative Example 1 and Comparative Example 2, it can be seen that compared with Comparative Example 1 (honeysuckle residue fermentation product + calcium oxide), the raw material struvite is added to the composite biological organic fertilizer of Comparative Example 2. As a result, the per-acre yield of cucumber increased from 5710.83kg (Comparative Example 1) to 5758.44kg (Comparative Example 2), and the yield growth rate compared to the unfertilized blank group increased from 22.7% (Comparative Example 1) to 23.6% (Comparative Example 2). This shows that in the preparation of composite biological organic fertilizer, adding struvite alone on the basis of the raw materials honeysuckle residue fermentation product and calcium oxide does not have a significant effect on increasing the yield of cucumber. This is mainly because the phosphate radical (PO4 3- ) will react with the Ca released by calcium oxide 2+ Combined to form insoluble calcium phosphate, resulting in low utilization of effective phosphorus; alkaline environment will also promote the NH4 + Converted into NH3, resulting in a high volatilization loss rate of nitrogen.

[0073] By comparing Comparative Example 1 and Comparative Example 3, it can be seen that compared with Comparative Example 1 (honeysuckle residue fermentation product + calcium oxide), the raw material nitrogen-doped biochar is added to the composite biological organic fertilizer of Comparative Example 3. As a result, the per-acre yield of cucumber is increased from 5710.83 kg (Comparative Example 1) to 6143.22 kg (Comparative Example 2), and the yield growth rate compared to the unfertilized blank group is increased from 22.7% (Comparative Example 1) to 31.9% (Comparative Example 2). This shows that in the preparation of composite biological organic fertilizer, adding nitrogen-doped biochar separately on the basis of raw materials honeysuckle residue fermentation product and calcium oxide can significantly increase cucumber yield.

[0074] By comparing Comparative Example 4 with Example 1, it can be seen that in the preparation of the composite biological organic fertilizer, nitrogen-doped biochar and struvite are added to the raw materials of honeysuckle residue fermentation and calcium oxide, and the two can produce a synergistic effect and synergistically increase cucumber yield.

[0075] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A composite bio-organic fertilizer, characterized in that: The composition comprises the following components in parts by weight: 95-100 parts of fermented honeysuckle residue, 31-33 parts of calcium oxide, 8-9 parts of struvite and 5-7 parts of nitrogen-doped biochar; The honeysuckle residue fermentation product is prepared by fermenting the honeysuckle residue with a composite bacterial agent, wherein the composite bacterial agent comprises thermophilic Chaetomium, thermophilic Sporotrichum, Paenibacillus polymyxa, Bacillus gelatinosa and Candida utilis.

2. The composite bio-organic fertilizer according to claim 1, wherein The mass of the composite bacterial agent is 0.3%-0.5% of the mass of the honeysuckle residue; Thermophilic Chaetomium: 0.8×10 9 -1.5×10 9 CFU / g; Thermospora: 0.6×10 9 -1.0×10 9 CFU / g; Paenibacillus polymyxa: 5.0×10 8 -8.0×10 8 CFU / g; Bacillus jelly: 5.0×10 8 -8.0×10 8 CFU / g; Candida utilis: 2.0×10 8 -5.0×10 8 CFU / g.

3. The composite bio-organic fertilizer according to claim 1 or 2, wherein The fermentation time is 15-20 days, the humidity is controlled at 50%-60%, and the temperature is 55-65℃.

4. The composite bio-organic fertilizer according to claim 1, wherein The preparation method of the nitrogen-doped biochar is as follows: A1. Mixing thiourea and biochar and grinding them thoroughly to obtain a mixture; A2. Under nitrogen protection, the mixture obtained in A1 was placed in a tube furnace for high-temperature pyrolysis to obtain a pyrolyzate; A3. Grind the pyrolyzate obtained in A2, rinse with deionized water, and then dry in an oven to obtain nitrogen-doped biochar.

5. The composite bio-organic fertilizer according to claim 4, wherein In A1, the mass ratio of thiourea to biochar is (1-1.5):

1.

6. The composite bio-organic fertilizer according to claim 4, wherein In A2, the specific operation of high-temperature pyrolysis is: heating rate of 5-10°C / min, heating to 800-820°C, and keeping warm for 2-2.5h.

7. The composite bio-organic fertilizer according to claim 4, wherein In A3, rinse with deionized water 3-5 times until the pH of the filtrate is 6.8-7.

2.

8. The composite bio-organic fertilizer according to claim 4, wherein In A3, the drying temperature is 60±5℃ and the drying time is 10-12h.

9. A method for preparing the composite bio-organic fertilizer according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Put the fermented product of honeysuckle residue, calcium oxide, struvite and nitrogen-doped biochar into a blender at a speed of 28-32 r / min and mix for 25-35 min to obtain a mixture; S2. Place the mixed material obtained in S1 into a pile and cover it with a breathable film. Turn the pile over once every 2-3 days at a temperature of 50-60°C. After 8-10 days, obtain a matured material. S3, drying and granulating the matured material obtained in S2 to obtain the composite bio-organic fertilizer.

10. An application of the composite bio-organic fertilizer according to any one of claims 1 to 8, characterized in that: Used for cucumber cultivation.

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