CN118652694A - A biochar conditioner composite and its preparation method and application - Google Patents

Abstract

The invention provides a biochar conditioner compound and a preparation method and application thereof, and relates to the technical field of soil conditioning materials. The biochar conditioner compound comprises the following components in parts by weight: 266-512 parts of biochar, 53-75 parts of humic acid, 9-15 parts of aluminum sulfate, 7-15 parts of calcium sulfonate, 5-15 parts of microbial agent and 2-8 parts of soil loosener; the specific surface area of the biochar is 130-150m ²/g, and the particle size is 25-50 meshes; the biochar conditioner compound is applied to the soil remediation of moderately severe saline-alkali soil, and has the effects of improving the physical and chemical properties of the soil, remedying the soil structure of the saline-alkali soil, reducing the volume weight of the soil, increasing the porosity and the expansion degree of the soil, enhancing the permeability and the water holding capacity of the soil and improving the water and fertilizer holding performance of the soil.

Description

A biochar conditioner composite and its preparation method and application

Technical Field

The invention belongs to the technical field of soil conditioning materials and relates to a biochar conditioner composite and a preparation method and application thereof.

Background Art

Saline-alkali soil contains more water-soluble salts or alkaline substances. Due to the high salt content and high alkalinity, the soil humus is seriously leached, the organic matter content is low, the soil physical and chemical properties and structure are poor, and the conditions for crop growth are not met, and even pose a threat to crop growth. At present, the main methods for saline-alkali land management include engineering measures, agronomic measures, chemical measures and biological measures.

Engineering measures can control the direction of water and salt migration, lower the groundwater level to below the critical depth, and adjust the soil salinity to create an environment suitable for crop growth; however, engineering measures have problems such as incomplete salt and alkali elimination, large engineering workload, high production costs, and poor input-output efficiency.

Agronomic measures include deep plowing, rotary tillage, and land preparation, "irrigation to wash away salt and improve soil", etc., to change the soil structure of the plowing layer, reduce evaporation, and increase deep infiltration to regulate soil water and salt migration; agronomic measures can also inhibit the upward movement of soil salt and reduce its accumulation in the plowing layer; but due to the limitations of soil sources and transportation costs, the application of agronomic measures has certain limitations.

Chemical measures use conditioners to adjust soil pH and accelerate desalination, thereby achieving the purpose of improving the soil; however, the large-scale use of inorganic and organic chemical conditioners may cause environmental pollution and potential ecological risks.

The biological measure method reduces the salt-alkali content of the soil, increases biodiversity, improves soil structure, and inhibits salt accumulation on the soil surface by adaptively planting salt-tolerant plants; the application of microbial agents improves the growth environment of plant roots and enhances plant resistance to disease and stress; the biological measure method has a long control cycle and is slow to take effect.

Chinese invention patent CN113637486A discloses a soil conditioner for moderately light saline-alkali land and its preparation method. The soil conditioner includes the following components calculated by weight: 45-78 parts of modified phosphogypsum powder, 12-18 parts of sulfur powder, 1-8 parts of humic acid, 2-5 parts of fulvic acid and 10-20 parts of calcium lignin sulfonate. Among them, sulfur powder can reduce soil pH, and sulfur bacteria in the soil can reduce soil alkalinity by decomposing sulfur into sulfuric acid, and continuously adjust the acidity; calcium lignin sulfonate can combine a large amount of humic acid and fulvic acid, which can promote root growth and improve nutrient absorption efficiency; at the same time, calcium lignin sulfonate is also conducive to fertilizer granulation and promotes disintegration after dissolving in water. Modified phosphogypsum powder can act as a slow-release carrier to gradually reduce the pH and alkalinity of the soil, thereby slowly improving the salinity and alkalinity of the soil.

In addition, Chinese invention patent CN105038802A discloses a soil structure conditioner for coastal clayey saline-alkali soil and its application in the cultivation of Osmanthus fragrans. The soil structure conditioner for coastal clayey saline-alkali soil has the following components in mass ratio: 13-18 parts of fulvic acid, 13-18 parts of biochar, 20-30 parts of polyvinyl alcohol, 0.48-0.93 parts of water retaining agent, 10-15 parts of aluminum sulfate, 0.2-0.9 parts of soil loosening agent, 50-55 parts of chicken manure, 9-15 parts of straw, 8-12 parts of alkali residue, 10-15 parts of Lythrum saline powder, 7-16 parts of hairy vetch powder, 5-10 parts of alkaliphilic Bacillus, and 4-8 parts of red-skinned Halobacterium. After 12 months of Osmanthus fragrans planting, the salt content of the 0-30cm soil layer is 0.31%-0.37%, and the soil bulk density is 0.91-0.96g/ ^cm3 The water-stable aggregate structure above 0.25 mm in the soil is 55%-59%, and the total porosity and aeration porosity of the soil are both increased.

However, the existing technologies still have the following deficiencies in saline-alkali soil remediation: they cannot effectively reduce soil salt content and soil pH at the same time; they do not show the ability to adsorb harmful substances, and the soil remediation efficiency is low; the soil permeability is poor, and the total porosity and ventilation porosity are both low. Moreover, the agronomic measures, biological measures and engineering measures require high costs, and the chemical measures have adverse effects on the environment.

Summary of the invention

The present invention aims at the problems existing in the prior art, provides a biochar conditioner composite and its preparation method and application, and aims at the physical and chemical properties of saline-alkali soil, soil structure, and the necessary conditions for crop growth, and utilizes the characteristics of biochar surface porosity, large surface area, and strong adsorption, and is compounded and mixed with humic acid, aluminum sulfate, calcium sulfonate, microbial agent, and soil loosening agent to obtain a conditioner composite. The biochar conditioner composite of the present invention is applied to the repair of medium and severe saline-alkali soil, and has the effects of significantly improving the physical and chemical properties of the soil, repairing the saline-alkali soil structure, reducing the soil bulk density, and increasing the soil porosity and swelling degree, and can also enhance the permeability and water holding capacity of the soil, and improve the water and fertilizer retention performance of the soil.

To achieve the above purpose, the technical solution adopted by the present invention is as follows:

First, the present invention provides a biochar conditioner composite, which comprises the following components by weight: 266-512 parts of biochar, 53-75 parts of humic acid, 9-15 parts of aluminum sulfate, 7-15 parts of calcium sulfonate, 5-15 parts of microbial agent and 2-8 parts of soil loosening agent;

The specific surface area of the biochar is 130-150 m ² /g.

Preferably, the biochar conditioner complex comprises the following components in parts by weight: 330-470 parts of biochar, 59-70 parts of humic acid, 10.8-13.5 parts of aluminum sulfate, 9-12 parts of calcium sulfonate, 6-12 parts of microbial agents and 3.8-6.5 parts of soil loosening agents.

Further preferably, the biochar conditioner complex comprises the following components in parts by weight: 400 parts of biochar, 65 parts of humic acid, 12 parts of aluminum sulfate, 10 parts of calcium sulfonate, 8 parts of microbial agent and 5 parts of soil loosening agent.

Preferably, the particle size of the biochar is 25-50 mesh.

Further preferably, the particle size of the biochar is 30-40 mesh.

Preferably, the biochar is ash charcoal from the combustion of biomass, and the biomass is selected from at least one of corn straw, sorghum straw, sunflower straw, rice straw, soybean straw, and rice husk.

Preferably, the calcium sulfonate is selected from at least one of calcium lignin sulfonate, calcium dodecylbenzene sulfonate and calcium cellulose sulfonate.

Preferably, the microbial agent is at least one selected from Bacillus subtilis, Paenibacillus gelatinosa, Bacillus megaterium and Bacillus sphaericus.

Then, the present invention provides a method for preparing the above-mentioned biochar conditioner composite, comprising the steps of:

(1) mixing biochar, humic acid, aluminum sulfate, calcium sulfonate, microbial agent and soil loosening agent to obtain a mixture;

(2) After the mixture is granulated, a biochar conditioner composite is obtained.

Preferably, in step (1), the mixing is performed by tossing until the mixture is uniformly mixed.

Preferably, step (2) is specifically as follows: the particles obtained by granulating the mixture are ventilated and air-dried for 3-5 days to reduce the moisture content to 30%, thereby obtaining a biochar conditioner complex.

Preferably, the prepared biochar conditioner complex is in powder or granular form.

Finally, the present invention provides the use of the above-mentioned biochar conditioner complex in repairing saline-alkali soil.

Preferably, the saline-alkali land is moderately or severely saline-alkali land.

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

1. The biochar conditioner complex of the present invention efficiently utilizes biochar to activate the solidified calcium ions in the soil to replace the sodium ions in the soil colloid; at the same time, it neutralizes the hydroxide ions in the soil, reduces the pH value of the soil, builds a good soil environment for crop growth, improves the soil's ability to retain and supply fertilizer, and has a good repair and treatment effect on saline-alkali soil.

2. The biochar conditioner complex of the present invention can quickly remove salt and alkali from the plow layer, improve the physical and chemical properties of the soil, and create conditions suitable for crop growth; the surface of biochar has a developed pore structure, which can increase the porosity of the soil, promote the formation of a granular structure, improve the soil structure, increase soil aeration, and provide a good environment and energy materials for crop growth; at the same time, the biochar conditioner complex of the present invention has a large specific surface area, which improves the adsorption capacity of harmful substances, promotes the degradation of harmful substances, and improves the efficiency of soil remediation.

3. The biochar conditioner complex of the present invention has a wide range of material sources and a simple preparation method. It has a good effect on the repair of saline-alkali soil, can reshape the soil structure, improve the physical and chemical properties of the soil, rapidly reduce the soil salt content, reduce the osmotic pressure between the soil and crops, inhibit the competitive absorption of various nutrients, and alleviate the stress of saline-alkali soil on crops. Compared with desulfurized gypsum, the biochar conditioner complex of the present invention has significantly improved the efficiency of de-alkali and salt control.

4. The biochar conditioner complex of the present invention uses biochar, humic acid, aluminum sulfate, calcium sulfonate, microbial agents and soil loosening agents in a synergistic manner to reduce the pH and salt content of saline-alkali soil, and completes desalination and alkali removal of medium and high saline-alkali land within one planting cycle, thereby promoting the improvement of soil quality and the normal growth of crops, and significantly increasing crop yields.

DETAILED DESCRIPTION

The following non-limiting examples can enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way. The following content is merely an exemplary description of the scope of the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, which should also fall within the scope of the present invention.

When the embodiments give numerical ranges, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meanings as those generally understood by those of ordinary skill in the art to which the present invention belongs.

The present invention is further described below by way of specific examples. Unless otherwise specified, the various chemical reagents used in the examples of the present invention are obtained through conventional commercial channels.

In the present invention, the technical indicators of the humic acid used meet the requirements of organic matter ≥80%, humic acid ≥40%, pH value 5.5-6.5, moisture ≤30%, and fineness 80 mesh, and other limit indicators meet the indicator requirements of NY525-2012 agricultural industry standards.

In the present invention, the microbial agent used complies with the GB 20287-2022 standard: the effective viable count (cfu) is ≥ 500 million/g (mL), and the dosage form is preferably a powder.

In the present invention, the soil loosening agent used is a chemical substance used to improve soil texture and increase soil aeration; the soil loosening agent ingredients include organic matter, minerals and other elements. The product standard indicators of the soil loosening agent used in the embodiment of the present invention are shown in Table 1:

Table 1

In the following examples, humic acid was purchased from Shanxi Jinfeng Biotechnology Co., Ltd., Kuangyuan brand, and the product number was original powder type II. Aluminum sulfate was purchased from Zhengzhou Shihong Environmental Protection Technology Co., Ltd., and the product number was powdered aluminum sulfate. Calcium sulfonate was calcium lignin sulfonate, purchased from Wuhan Jiyesheng Chemical Co., Ltd., Jiyesheng brand, and the product number was calcium lignin sulfonate (8061). Microbial agents were purchased from Sinochem Modern Agriculture (Jilin) Co., Ltd., a product of Mapowo, and the strains were Bacillus subtilis and Bacillus jelly, with an effective viable count (cfu) ≥ 500 million/g. Soil loosening agent was purchased from Stanley Agricultural Group Co., Ltd., Stanley brand, and the product number was soil loosening agent (1810). Biochar was ash charcoal after burning corn stalks, which was sieved through a 30-40 mesh sieve to obtain an intermediate particle size component; the specific surface area of the obtained biochar was ^130-150m2 /g. The "Wen'an" wettable powder is a rice blast and tricyclazole wettable powder, which has a total active ingredient content of 20%, a net rice blast content of 10%, and a tricyclazole content of 10%. The manufacturer is Hebei Zhongbao Green Crop Science and Technology Co., Ltd.

For the above components, products from different manufacturers have no significant effect on the effects.

Example 1

A biochar conditioner composite, comprising the following components by weight: 400 parts of biochar, 65 parts of humic acid, 12 parts of aluminum sulfate, 10 parts of calcium sulfonate, 8 parts of microbial agent and 5 parts of soil loosening agent;

Among them, the specific surface area of biochar is 130-150m ² /g.

A method for preparing a biochar conditioner composite comprises the steps of:

(1) Mixing biochar, humic acid, aluminum sulfate, calcium sulfonate, microbial agent and soil loosening agent according to weight proportions, turning and tossing until the mixture is uniform, thereby obtaining a mixture;

(2) After the mixture is extruded and granulated, the obtained granules are ventilated and air-dried for 4 days until the moisture content is reduced to 30%, thereby obtaining a biochar conditioner composite.

Example 2

A biochar conditioner composite, comprising the following components by weight: 330 parts of biochar, 59 parts of humic acid, 10.8 parts of aluminum sulfate, 9 parts of calcium sulfonate, 6 parts of microbial agent and 3.8 parts of soil loosening agent;

Among them, the specific surface area of biochar is 130-150m ² /g.

The preparation method of the biochar conditioner composite is the same as that in Example 1.

Example 3

A biochar conditioner composite, comprising the following components by weight: 470 parts of biochar, 70 parts of humic acid, 13.5 parts of aluminum sulfate, 12 parts of calcium sulfonate, 12 parts of microbial agent and 6.5 parts of soil loosening agent;

Among them, the specific surface area of biochar is 130-150m ² /g.

The preparation method of the biochar conditioner composite is the same as that in Example 1.

Example 4

A biochar conditioner composite, comprising the following components by weight: 266 parts of biochar, 53 parts of humic acid, 9 parts of aluminum sulfate, 7 parts of calcium sulfonate, 5 parts of microbial agent and 2 parts of soil loosening agent;

Among them, the specific surface area of biochar is 130-150m ² /g.

The preparation method of the biochar conditioner composite is the same as that in Example 1.

Example 5

A biochar conditioner compound, comprising the following components by weight: 512 parts of biochar, 75 parts of humic acid, 15 parts of aluminum sulfate, 15 parts of calcium sulfonate, 15 parts of microbial agent and 8 parts of soil loosening agent;

Among them, the specific surface area of biochar is 130-150m ² /g.

The preparation method of the biochar conditioner composite is the same as that in Example 1.

Comparative Example 1

Different from Example 1, the weight proportions of the components of the biochar conditioner composite are different.

The biochar conditioner complex consists of the following components, measured in parts by weight: 200 parts of biochar, 165 parts of humic acid, 82 parts of aluminum sulfate, 40 parts of calcium sulfonate, 8 parts of microbial agents and 5 parts of soil loosening agents.

The rest is the same as in Example 1.

Comparative Example 2

Different from Example 1, in the biochar conditioner composite, calcium sulfonate is replaced by humic acid.

The biochar conditioner complex consists of the following components, measured in parts by weight: 400 parts of biochar, 75 parts of humic acid, 12 parts of aluminum sulfate, 8 parts of microbial agents and 5 parts of soil loosening agents.

The rest is the same as in Example 1.

Comparative Example 3

Different from Example 1, the biochar conditioner composite does not contain humic acid.

Specifically: humic acid is replaced by aluminum sulfate, calcium sulfonate, microbial agents and soil loosening agents according to the weight ratio.

The biochar conditioning agent composite is composed of the following components in parts by weight:

400 parts of biochar;

A mixture of 100 parts of aluminum sulfate, calcium sulfonate, microbial agent and soil loosening agent (the weight ratio of aluminum sulfate, calcium sulfonate, microbial agent and soil loosening agent is 12:10:8:5).

The rest is the same as in Example 1.

Comparative Example 4

Different from Example 1, the biochar conditioner composite consists of the following components in parts by weight: 400 parts of biochar and 100 parts of calcium sulfonate.

The rest is the same as in Example 1.

Comparative Example 5

Different from Example 1, the weight proportions of the components of the biochar conditioner composite are different.

The biochar conditioner complex is composed of the following components in parts by weight: 400 parts of biochar, 22 parts of humic acid, 35 parts of aluminum sulfate, 30 parts of calcium sulfonate, 10 parts of microbial agents and 3 parts of soil loosening agents.

The rest is the same as in Example 1.

Comparative test

The biochar conditioner composites prepared in Examples 1-5 and Comparative Examples 1-5 were tested and compared.

The experiment was conducted in a moderately to severely saline-alkali land experimental field somewhere in Jilin Province.

Before the use of the biochar conditioner complex, the soil in the test field was both saline and alkaline, the surface was barren, the soil structure was damaged, sticky when wet and hard when dry, the vegetation coverage rate was 20%-50%, and the surface soil often had white salt and alkali spots, scars, and low organic matter content. The soil was very sticky, with poor ventilation and water permeability, and the crop growth environment was poor, causing plant wilting, poisoning and root rot.

Experimental field 1: pH value 8.96-9.50, total salt content 3.8-4.7 g/kg.

Experimental field 2: pH value 9.5-10.3, total salt content 5.5-6.0g/kg.

The dosage of biochar conditioner complex is shown in Table 2.

Table 2

The test field was deeply plowed (15-20 cm) and randomly divided into 30 parts, each with 3 parts, and each group was evenly applied with the biochar conditioning agent complex of the embodiment or the comparative example. The application amount of the biochar conditioning agent complex was 2.2 tons/mu (severe saline-alkali soil) and 1.8 tons/mu (moderate saline-alkali soil). Rice was planted one month later.

Experimental time: mid-April 2023 to early October 2023.

Rice variety: Dongdao 122.

Planting specifications: rice row spacing 30cm, plant spacing 12cm, sowing depth 2cm.

Fertilizer usage: Base fertilizer is 2.5 tons/mu of bio-organic fertilizer (product standard: NY525-2021) and 30 kg/mu of compound fertilizer. Topdressing is divided into two times: 10-15 days after transplanting, apply tillering fertilizer, 10 kg/mu of urea; 35-40 days after transplanting, apply heading fertilizer, 12 kg of urea.

Disease and insect resistant drugs: 1. Control of rice blast: Select excellent disease-resistant varieties and disinfect seeds before raising seedlings. Use 20% "Tricyclazole" to soak and coat seeds; use 80 grams of "Bian'an" wettable powder (Iro Tricyclazole wettable powder) per mu for leaf blast treatment during the booting stage; 2. Control of sheath blight: Use 50% "Tujunte" wettable powder per mu, prepare 1500 times liquid spray for aerial defense; 3. Control of rice planthoppers: Use a high-content imidacloprid single agent of 4-5 grams of active ingredient per mu or 25% pymetrozine 24 grams per mu; Control of striped stem borers: Use 0.2% hypertonic emamectin benzoate 40-60 ml per mu or 30 ml of cypermethrin per mu.

Different biochar conditioner composites of Examples 1-5 of the present invention and Comparative Examples 1-5 were used to repair saline-alkali soil. The results of soil pH, total salt content and rice crop yield before and after repair are shown in Table 3.

Table 3

From the comparison of the results in Table 3, we can see that the saline-alkali soils in the two experimental fields were desalted and dealkaliized within one planting cycle, which improved the soil quality and created suitable conditions for crop growth.

After restoration, the pH value of experimental field 1 decreased by 1.04-1.66, and the salt content decreased by 0.52-1.94 g/kg. The pH value of the restored soil was below 8.4, the salt content dropped to below 3.7 g/kg, and the organic matter content in the soil reached 15-20 g/kg.

After restoration, the pH value of experimental field 2 decreased by 1.37-1.95, and the salt content decreased by 2.5-2.8 g/kg. The pH value of the restored soil was below 8.5, the salt content dropped to below 3.4 g/kg, and the organic matter content in the soil reached 15-25 g/kg.

Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims (10)

1. The biochar conditioner compound is characterized by comprising the following components in parts by weight: 266-512 parts of biochar, 53-75 parts of humic acid, 9-15 parts of aluminum sulfate, 7-15 parts of calcium sulfonate, 5-15 parts of microbial agent and 2-8 parts of soil loosener;

The specific surface area of the biochar is 130-150m ²/g.

2. The biochar conditioner complex according to claim 1, comprising the components in parts by weight: 330-470 parts of biochar, 59-70 parts of humic acid, 10.8-13.5 parts of aluminum sulfate, 9-12 parts of calcium sulfonate, 6-12 parts of microbial agent and 3.8-6.5 parts of soil loosener.

3. The biochar conditioner complex according to claim 2, comprising the components in parts by weight: 400 parts of biochar, 65 parts of humic acid, 12 parts of aluminum sulfate, 10 parts of calcium sulfonate, 8 parts of microbial agent and 5 parts of soil loosener.

4. The biochar conditioner complex of claim 1, wherein the biochar has a particle size of 25-50 mesh.

5. The biochar conditioner complex of claim 1, wherein the biochar is a biomass combustion ash char, and the biomass is at least one selected from the group consisting of corn stover, sorghum stover, sunflower straw, rice straw, soybean straw, and rice hulls.

6. The biochar conditioner complex of claim 1, wherein the calcium sulfonate is selected from at least one of calcium lignosulfonate, calcium dodecylbenzene sulfonate, and calcium cellulose sulfonate.

7. The biochar conditioner complex according to claim 1, wherein the microbial agent is selected from at least one of bacillus subtilis, paenibacillus mucilaginosus, bacillus megaterium, bacillus sphaericus.

8. A method of preparing the biochar conditioner complex of any one of claims 1-7, comprising the steps of:

(1) Mixing biochar, humic acid, aluminum sulfate, calcium sulfonate, microbial agent and soil loosening agent to obtain a mixture;

(2) And granulating the mixture to obtain the biochar conditioner compound.

9. The method according to claim 8, wherein,

In the step (1), the mixing is turning over and throwing until the mixing is uniform;

the step (2) comprises the following steps: and (3) ventilating and airing the granules obtained by granulating the mixture for 3-5 days, and reducing the water content to 30% to obtain the biochar conditioner compound.

10. Use of the biochar conditioner complex of any one of claims 1-7 for restoring saline-alkali soil.