Multifunctional liquid mulching film based on agricultural organic waste and preparation method thereof

Abstract

The invention discloses a multifunctional liquid mulching film based on agricultural organic waste and a preparation method thereof, and belongs to the technical field of agricultural environment-friendly materials. The liquid mulching film is prepared from the following raw materials in percentage by mass: 50%-70% of an agricultural organic waste base material, 1%-5% of a complex microbial inoculant, 0.5%-2% of a medium trace element additive, 3%-8% of a functional aid and the balance of water. The preparation method comprises the following steps: weighing the raw materials; pretreating raw materials; performing two-stage fermentation; performing functional compounding; and performing high-pressure homogenization. The liquid mulching film can prevent and inhibit weeds; dynamically preserving soil moisture; the method is environment-friendly; field tests prove that the mulching film can increase soil organic matters by 0.3-0.5%, increase crop yield by 8-15%, and save cost by 76-95 yuan per mu.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural environmental protection materials, and specifically relates to a multifunctional liquid mulch film based on agricultural organic waste and a preparation method thereof. Background Art

[0002] Existing liquid mulch films mainly rely on petrochemical raw materials (such as polyvinyl alcohol) or single straw components, and have the following problems: high raw material cost: the price of petrochemical-based materials fluctuates greatly, and the per-acre cost exceeds 100 yuan; single function: traditional products only have the function of soil moisture conservation, lacking the synergistic effects of weed prevention and soil fertility improvement; poor degradation performance: the degradation period of some biological base films is as long as 120 days, affecting subsequent tillage.

[0003] Therefore, how to provide a multifunctional liquid mulch film based on agricultural organic waste with the functions of weed prevention and inhibition, dynamic soil moisture conservation, slow-release fertility, and environmental friendliness and its preparation method is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention provides a multifunctional liquid mulch film based on agricultural organic waste and a preparation method thereof.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A multifunctional liquid mulch film based on agricultural organic waste is made of the following raw materials in mass percentages:

[0007] 50%-70% of agricultural organic waste base material, 1%-5% of compound bacterial agent, 0.5%-2% of medium and trace element additive, 3%-8% of functional auxiliary agent, and the balance is water;

[0008] The above-mentioned agricultural organic waste base material includes vegetable straws, tail vegetables, fallen leaves and field gramineous straws, and the mass ratio of vegetable straws, tail vegetables, fallen leaves and field gramineous straws is (20-30):(10-20):(10-15):(10-25);

[0009] The above-mentioned compound bacterial agent includes white rot fungus bacterial agent with viable bacteria number ≥ 1×10 9 CFU / mL, thermophilic Bacillus stearothermophilus bacterial agent with viable bacteria number ≥ 1×10 9 CFU / mL, and Azotobacter chroococcum bacterial agent with viable bacteria number ≥ 1×10 9 CFU / mL. The mass ratio of white rot fungus bacterial agent, thermophilic Bacillus stearothermophilus bacterial agent and Azotobacter chroococcum bacterial agent is 2:1:1;

[0010] The above-mentioned medium and trace element additive includes calcium sulfate, magnesium sulfate and borax, and the mass ratio of calcium sulfate, magnesium sulfate and borax is (40-50):(20-30):(10-15);

[0011] The above functional additives include alginate oligosaccharide, sodium carboxymethyl cellulose, and nano-silica, and the mass ratio of alginate oligosaccharide, sodium carboxymethyl cellulose, and nano-silica is (0.8 - 1.2):(1 - 3):(0.1 - 0.5).

[0012] The present invention also provides a preparation method of a multifunctional liquid mulch film based on agricultural organic waste, comprising the following steps:

[0013] (1) Weigh each raw material according to the above multifunctional liquid mulch film based on agricultural organic waste;

[0014] (2) Raw material pretreatment: Crush vegetable straws and field gramineous straws, press and dehydrate tail vegetables, subject vegetable straws, tail vegetables, fallen leaves, and field gramineous straws to steam explosion treatment, and enzymatically hydrolyze the materials after steam explosion treatment to obtain a degradation liquid;

[0015] (3) Two-stage fermentation:

[0016] The first stage: Inoculate the degradation liquid obtained in step (2) with a Bacillus stearothermophilus bacterium agent and ferment;

[0017] The second stage: Lower the temperature, inoculate with a Phanerochaete chrysosporium bacterium agent and a Azotobacter chroococcum bacterium agent, and ferment to obtain a fermentation liquid;

[0018] (4) Functional compounding: Add medium and trace element additives and functional additives to the fermentation liquid obtained in step (3), and mix evenly to obtain a mixture;

[0019] (5) High-pressure homogenization: Subject the mixture obtained in step (4) to high-pressure homogenization to obtain a liquid mulch film.

[0020] Furthermore, in step (2), the vegetable straws and gramineous straws are crushed into sections of 1 - 3 cm, and the tail vegetables are pressed and dehydrated to a moisture content of ≤ 70%.

[0021] Furthermore, in step (2), the pressure of the steam explosion treatment is 1.2 - 1.8 MPa, the temperature is 188 - 210 °C, and the pressure holding time is 3 - 8 minutes.

[0022] The beneficial effect of adopting the above further technical solution: The steam explosion treatment reduces the crystallinity of straw cellulose.

[0023] Furthermore, in step (2), water and cellulase are added to the materials after steam explosion treatment for enzymatic hydrolysis. The enzyme activity of the cellulase is 50 - 100 FPU / mL, the enzyme addition amount is 0.5% - 1.5% of the mass of the materials after steam explosion treatment, the enzymatic hydrolysis temperature is 50 - 65 °C, and the enzymatic hydrolysis time is 12 - 24 hours.

[0024] Further, in step (3), the fermentation temperature in the first stage is 55°C, and the fermentation time is 48 hours; in the second stage, the temperature is reduced to 37°C, the fermentation temperature is 37°C, and the fermentation time is 72 hours.

[0025] Beneficial effects of adopting the above further technical solution: improve the polysaccharide content in the fermentation broth.

[0026] Further, in step (5), the pressure of high-pressure homogenization is 50 - 80 MPa, the flow rate of high-pressure homogenization is 20 - 40 L / h, the temperature of high-pressure homogenization is 35 - 50°C, the time of high-pressure homogenization is 15 - 30 minutes, and the viscosity of the liquid mulch is 300 - 500 mPa·s.

[0027] Beneficial effects of adopting the above further technical solution: high-pressure homogenization makes the light transmittance of the film layer ≤ 15%.

[0028] Beneficial effects of the present invention: The present invention discloses a multifunctional liquid mulch based on agricultural organic waste and its preparation method. Through a technical system of hierarchical treatment of agricultural waste - co-fermentation with compound microbial agents - precise compounding of functional materials, high-value utilization of waste is realized. The above liquid mulch has the following characteristics:

[0029] 1. Weed prevention and inhibition: Nano-lignin particles (200 - 500 nm) make the light transmittance of the film layer ≤ 15%, inhibiting the photosynthesis of weeds;

[0030] 2. Dynamic soil moisture conservation: Utilizing the pH-responsive characteristics of humic acid, the water absorption expansion rate of the film layer in the rainy season increases by 30%, and the shrinkage in the dry season reduces water evaporation by 40%;

[0031] 3. Environmentally friendly: Natural degradation in 60 - 90 days, with a residue content < 5%.

[0032] Verified by field trials, this mulch can increase soil organic matter by 0.3 - 0.5%, increase crop yield by 8 - 15%, and save 76 - 95 yuan per mu in cost.

[0033] Raw material innovation: Four kinds of agricultural wastes, vegetable straws, tail vegetables, fallen leaves, and field gramineous straws, are compounded in a specific ratio, and their cellulose (18 - 23%), lignin (12 - 18%), and pectin (8 - 15%) are used to construct the film base material by complementarity;

[0034] Process innovation: Adopt a two-stage temperature-controlled fermentation process. In the first stage (55°C), thermophilic bacteria rapidly degrade crude fiber, and in the second stage (37°C), white rot fungi and nitrogen-fixing bacteria synergistically synthesize functional metabolites. Specific embodiments

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] Example 1

[0037] A preparation method of a multifunctional liquid mulch film based on agricultural organic waste includes the following steps:

[0038] (1) Weigh 25 kg of cucumber straws, 15 kg of Chinese cabbage waste, 12 kg of poplar leaves, 18 kg of corn straws, 3 kg of compound microbial agents, 0.5 kg of calcium sulfate, 0.3 kg of magnesium sulfate, 0.1 kg of borax, 0.8 kg of alginate oligosaccharide, 2 kg of CMC, 0.3 kg of nano-SiO₂, and 22.9 kg of water. Among them, the compound microbial agent includes a white rot fungus agent with a viable count of 1×10 9 CFU / mL, a Bacillus stearothermophilus agent with a viable count of 1×10 9 CFU / mL, and a Azotobacter chroococcum agent with a viable count of 1×10 9 CFU / mL. The mass ratio of the white rot fungus agent, the Bacillus stearothermophilus agent, and the Azotobacter chroococcum agent is 2:1:1;

[0039] (2) Raw material pretreatment: Crush the cucumber straws and corn straws into sections of 1 - 3 cm, press and dehydrate the Chinese cabbage waste until the water content is 70%, and perform steam explosion treatment on the cucumber straws, Chinese cabbage waste, poplar leaves, and corn straws to reduce the crystallinity of the straw cellulose to 32%. The pressure of the steam explosion treatment is 1.5 MPa, the temperature is 200 °C, and the pressure holding time is 5 minutes. Add water and cellulase to the materials after the steam explosion treatment for enzymatic hydrolysis. The enzyme activity of the cellulase is 80 FPU / mL, the enzyme addition amount is 1% of the mass of the materials after the steam explosion treatment, the enzymatic hydrolysis temperature is 60 °C, and the enzymatic hydrolysis time is 18 hours to obtain a degradation liquid;

[0040] (3) Two-stage fermentation:

[0041] The first stage: Inoculate the Bacillus stearothermophilus agent into the degradation liquid obtained in step (2) and ferment. The fermentation temperature is 55 °C, and the fermentation time is 48 hours;

[0042] The second stage: Cool down to 37 °C, inoculate the white rot fungus agent and the Azotobacter chroococcum agent, and ferment. The fermentation temperature is 37 °C, and the fermentation time is 72 hours to obtain a fermentation liquid, and the polysaccharide content of the fermentation liquid reaches 12.5 mg / mL;

[0043] (4) Functional compounding: Add micronutrient additives and functional aids to the fermentation broth obtained in step (3), and mix evenly to obtain a mixture.

[0044] (5) High-pressure homogenization: Homogenize the mixture obtained in step (4) under high pressure. The pressure of high-pressure homogenization is 60 MPa, the flow rate is 30 L / h, the temperature is 40 °C, and the time is 20 minutes, to obtain a liquid mulch film with a viscosity of 420 mPa·s and a light transmittance of 13%.

[0045] Application effect:

[0046] Weed control rate: 82.5% (89% for the control PE mulch film); Soil moisture content: increased by 18.7% compared to the bare land; 60-day degradation rate: 91.3%.

[0047] Example 2

[0048] A preparation method of a multifunctional liquid mulch film based on agricultural organic waste, comprising the following steps:

[0049] (1) Weigh 20 kg of cucumber straw, 10 kg of Chinese cabbage tailings, 10 kg of poplar leaves, 10 kg of corn straw, 1 kg of compound bacterial agent, 0.4 kg of calcium sulfate, 0.2 kg of magnesium sulfate, 0.1 kg of borax, 0.9 kg of alginate oligosaccharide, 3 kg of CMC, 0.2 kg of nano-SiO₂, and 44.2 kg of water. Among them, the compound bacterial agent includes a white rot fungus agent with viable bacteria number ≥ 1×10 9 CFU / mL, a Bacillus stearothermophilus agent with viable bacteria number ≥ 1×10 9 CFU / mL, and a Azotobacter chroococcum agent with viable bacteria number ≥ 1×10 9 CFU / mL. The mass ratio of the white rot fungus agent, the Bacillus stearothermophilus agent, and the Azotobacter chroococcum agent is 2:1:1.

[0050] (2) Raw material pretreatment: Crush the cucumber straw and corn straw into sections of 1-3 cm, press and dehydrate the Chinese cabbage tailings until the moisture content ≤ 70%. Steam explosion treatment is carried out on the cucumber straw, Chinese cabbage tailings, poplar leaves, and corn straw. The pressure of steam explosion treatment is 1.2 MPa, the temperature is 188 °C, and the pressure holding time is 3 minutes. Add water and cellulase to the materials after steam explosion treatment for enzymatic hydrolysis. The enzyme activity of cellulase is 50 FPU / mL, the enzyme addition amount is 0.5% of the mass of the materials after steam explosion treatment, the enzymatic hydrolysis temperature is 50 °C, and the enzymatic hydrolysis time is 12 hours to obtain a degradation liquid.

[0051] (3) Two-stage fermentation:

[0052] The first stage: inoculate the thermophilic Bacillus stearothermophilus agent into the degradation liquid obtained in step (2), ferment at a fermentation temperature of 55 °C for 48 hours;

[0053] The second stage: cool down to 37 °C, inoculate the white rot fungus agent and the Azotobacter chroococcum agent, ferment at a fermentation temperature of 37 °C for 72 hours to obtain a fermentation liquid;

[0054] (4) Functional compounding: add trace elements additives and functional auxiliaries to the fermentation liquid obtained in step (3), mix evenly to obtain a mixture;

[0055] (5) High-pressure homogenization: subject the mixture obtained in step (4) to high-pressure homogenization at a pressure of 50 MPa, a flow rate of 20 L / h, a temperature of 35 °C, and a time of 15 minutes to obtain a liquid mulch film with a viscosity of 300 mPa·s.

[0056] Example 3

[0057] A preparation method of a multifunctional liquid mulch film based on agricultural organic waste, comprising the following steps:

[0058] (1) Weigh 30 kg of cucumber straws, 20 kg of Chinese cabbage tail vegetables, 10 kg of poplar leaves, 10 kg of corn straws, 5 kg of compound bacteria agent, 0.5 kg of calcium sulfate, 0.3 kg of magnesium sulfate, 0.15 kg of borax, 1.2 kg of alginate oligosaccharide, 3 kg of CMC, 0.5 kg of nano-SiO₂, and 19.35 kg of water. Among them, the compound bacteria agent includes a white rot fungus agent with viable bacteria number ≥ 1×10 9 CFU / mL, a thermophilic Bacillus stearothermophilus agent with viable bacteria number ≥ 1×10 9 CFU / mL, and an Azotobacter chroococcum agent with viable bacteria number ≥ 1×10 9 CFU / mL. The mass ratio of the white rot fungus agent, the thermophilic Bacillus stearothermophilus agent, and the Azotobacter chroococcum agent is 2:1:1;

[0059] (2) Raw material pretreatment: crush the cucumber straws and corn straws into 1 - 3 cm segments, press and dehydrate the Chinese cabbage tail vegetables until the moisture content ≤ 70%, subject the cucumber straws, Chinese cabbage tail vegetables, poplar leaves, and corn straws to steam explosion treatment at a pressure of 1.8 MPa, a temperature of 210 °C, and a pressure maintaining time of 8 minutes, add water and cellulase to the materials after steam explosion treatment for enzymatic hydrolysis. The enzyme activity of the cellulase is 100 FPU / mL, the enzyme addition amount is 1.5% of the mass of the materials after steam explosion treatment, the enzymatic hydrolysis temperature is 65 °C, and the enzymatic hydrolysis time is 24 hours to obtain a degradation liquid;

[0060] (3) Two-stage fermentation:

[0061] The first stage: inoculate the degradation liquid obtained in step (2) with a Bacillus stearothermophilus inoculum and ferment at a fermentation temperature of 55 °C for 48 hours;

[0062] The second stage: cool down to 37 °C, inoculate with a white rot fungus inoculum and an Azotobacter chroococcum inoculum, and ferment at a fermentation temperature of 37 °C for 72 hours to obtain a fermentation broth;

[0063] (4) Functional compounding: add trace element additives and functional aids to the fermentation broth obtained in step (3) and mix evenly to obtain a mixture;

[0064] (5) High-pressure homogenization: subject the mixture obtained in step (4) to high-pressure homogenization at a pressure of 80 MPa, a flow rate of 40 L / h, a temperature of 50 °C, and a time of 30 minutes to obtain a liquid mulch film with a viscosity of 500 mPa·s.

[0065] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multifunctional liquid mulching film based on agricultural organic waste, characterized in that, It is made from raw materials including the following mass percentages: 50%-70% of agricultural organic waste substrate, 1%-5% of compound microbial inoculum, 0.5%-2% of medium and trace element additive, 3%-8% of functional auxiliary agent, and the balance is water; The agricultural organic waste substrate includes vegetable straws, tail vegetables, fallen leaves and field gramineous straws, and the mass ratio of vegetable straws, tail vegetables, fallen leaves and field gramineous straws is (20-30):(10-20):(10-15):(10-25); The composite microbial agent includes a white rot fungus microbial agent with viable count ≥ 1×10 9 CFU / mL, a Bacillus stearothermophilus microbial agent with viable count ≥ 1×10 9 CFU / mL, and a Azotobacter chroococcum microbial agent with viable count ≥ 1×10 9 CFU / mL. The mass ratio of the white rot fungus microbial agent, the Bacillus stearothermophilus microbial agent, and the Azotobacter chroococcum microbial agent is 2:1:1; The medium and trace element additive includes calcium sulfate, magnesium sulfate and borax, and the mass ratio of calcium sulfate, magnesium sulfate and borax is (40-50):(20-30):(10-15); The functional auxiliary agent includes alginate oligosaccharide, sodium carboxymethyl cellulose and nano-silica, and the mass ratio of alginate oligosaccharide, sodium carboxymethyl cellulose and nano-silica is (0.8-1.2):(1-3):(0.1-0.5).

2. A preparation method of a multifunctional liquid mulching film based on agricultural organic waste, characterized in that, It includes the following steps: (1) Weigh each raw material according to the multifunctional liquid mulching film based on agricultural organic waste described in Claim 1; (2) Raw material pretreatment: Crush vegetable straws and field gramineous straws, press and dehydrate tail vegetables, conduct steam explosion treatment on vegetable straws, tail vegetables, fallen leaves and field gramineous straws, and enzymatically hydrolyze the materials after steam explosion treatment to obtain a degradation liquid; (3) Two-stage fermentation: The first stage: Inoculate the degradation liquid obtained in step (2) with Bacillus stearothermophilus microbial inoculum and ferment; The second stage: Cool down, inoculate with white rot fungus microbial inoculum and Azotobacter chroococcum microbial inoculum, and ferment to obtain a fermentation liquid; (4) Functional compounding: Add medium and trace element additive and functional auxiliary agent to the fermentation liquid obtained in step (3), and mix evenly to obtain a mixture; (5) High-pressure homogenization: Subject the mixture obtained in step (4) to high-pressure homogenization to obtain a liquid mulching film.

3. The preparation method of a multifunctional liquid mulching film based on agricultural organic waste according to claim 2, wherein, In step (2), crush vegetable straws and gramineous straws into sections of 1-3 cm, and press and dehydrate tail vegetables until the water content ≤ 70%.

4. The preparation method of a multifunctional liquid mulching film based on agricultural organic waste according to claim 2, characterized in that, In step (2), the pressure of steam explosion treatment is 1.2-1.8 MPa, the temperature is 188-210 °C, and the pressure holding time is 3-8 minutes.

5. The preparation method of a multifunctional liquid mulching film based on agricultural organic waste according to claim 2, wherein, In step (2), add water and cellulase to the materials after steam explosion treatment for enzymatic hydrolysis. The enzyme activity of cellulase is 50-100 FPU / mL, the enzyme addition amount is 0.5%-1.5% of the mass of the materials after steam explosion treatment, the enzymatic hydrolysis temperature is 50-65 °C, and the enzymatic hydrolysis time is 12-24 hours.

6. The preparation method of a multifunctional liquid mulching film based on agricultural organic waste according to claim 2, wherein, In step (3), the fermentation temperature in the first stage is 55 °C and the fermentation time is 48 hours; cool down to 37 °C in the second stage, the fermentation temperature is 37 °C, and the fermentation time is 72 hours.

7. The preparation method of a multifunctional liquid mulching film based on agricultural organic waste according to claim 2, wherein, In step (5), the pressure of high-pressure homogenization is 50-80 MPa, the flow rate of high-pressure homogenization is 20-40 L / h, the temperature of high-pressure homogenization is 35-50 °C, the time of high-pressure homogenization is 15-30 minutes, and the viscosity of the liquid mulching film is 300-500 mPa·s.