CN106116946B - Biological organic fertilizer for repairing soil heavy metal and preparation method thereof - Google Patents

Abstract

The invention discloses a biological organic fertilizer for repairing soil heavy metal, which is prepared by preparing animal wastes, straws, kitchen waste and specially treated microorganism mixed flora into the biological organic fertilizer, and can reduce the content of soil high-valence heavy metal ions by more than 8 percent; the heavy metal enrichment of crops is reduced by more than 10 percent; particularly, the reduction of Cr reaches more than 70 percent; the yield of crops is increased by more than 5 percent, and the method has various effects of water retention, fertilizer retention, soil structure improvement and the like, and is a novel bioremediation method with low cost, high efficiency, simplicity, convenience and environmental friendliness.

Description

A kind of bio-organic fertilizer for repairing heavy metals in soil and preparation method thereof

technical field

The product relates to the technical field of agricultural fertilizers, in particular to a bio-organic fertilizer for repairing heavy metals in soil.

Background technique

At present, due to the increasing number of heavy metal mining, smelting, processing and commercial manufacturing activities by humans, many heavy metals such as lead, mercury, cadmium, cobalt, etc. enter the atmosphere, water, and soil, causing serious environmental pollution. Heavy metal pollution of soil It is an increasingly serious environmental problem, which has attracted the attention of the central government. In the "2016 Central Government's Budget for Tax Return and Payment to Local Governments", the budget for soil pollution control is as high as 9.089 billion yuan. Heavy metal pollutants in soil mainly come from sewage irrigation, industrial waste residue, municipal waste, industrial waste stacking and atmospheric deposition. The industrial wastewater, which accounts for a large proportion of the sewage, is relatively complex in composition, and contains various heavy metals that are difficult to biodegrade to varying degrees, and is the main source of heavy metal pollutants in soil. At present, the world's average annual emission of Hg is about 15,000 tons, Cu is about 3.4 million tons, Pb is about 5 million tons, Mn is about 15 million tons, and Ni is about 1 million tons. According to the survey of the Ministry of Agriculture of my country, in the sewage irrigation area of about 1.4 million hectares, the land area polluted by heavy metals accounts for 64.8% of the sewage irrigation area, of which 46.7% are lightly polluted, 9.7% are moderately polluted, and 9.7% are severely polluted. 8.4%.

At home and abroad, the methods used to degrade or eliminate heavy metal pollution in soil can be basically divided into three categories: physical methods, chemical remediation techniques, and bioremediation techniques. Physical/chemical remediation technology is mainly based on the physical and chemical properties of soil and the different characteristics of heavy metals, and uses physical and chemical means to separate or fix heavy metals in soil to clean soil and reduce environmental and health risks of pollutants. Physical and chemical restoration techniques include soil replacement, foreign soil, deep ploughing, soil leaching, thermal desorption, vitrification, and electric restoration. The physical and chemical technology is convenient and flexible to implement and has a short cycle. It is suitable for the treatment of various heavy metals and has been widely used in the remediation of heavy metal-contaminated soil engineering. its promotion and application. Therefore, there is an urgent need to develop a novel bioremediation method that is low-cost, efficient, simple, and environmentally friendly.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the present invention provides an efficient, simple and environmentally friendly bio-organic fertilizer for repairing heavy metals in soil.

In recent years, due to the increase in the degree of agricultural mechanization, agricultural machinery has replaced livestock. Thus, the amount of straw used as feed is greatly reduced. When the crops are mature every year, the large amount of straw left by farmers after harvesting the crops can only be burned. The open burning of straw pollutes the atmosphere, wastes resources, and even affects and interferes with the normal order of the economy, creating new security risks. The processing of straw into bio-organic fertilizer not only avoids environmental pollution and resource waste caused by incineration, but also decomposes the straw into relatively stable humus through a series of biochemical reactions, supplementing the nutrients necessary for crops such as nitrogen, phosphorus and potassium. elements, thereby improving soil structure. At the same time, kitchen waste is also one of the important causes of urban pollution. Therefore, in the present invention, the rich nutrition of kitchen waste is also effectively utilized, and it is fermented and biologically transformed into a biological organic fertilizer, thereby turning waste into treasure and reducing urban pollution.

According to literature reports, Bacillus mucilaginosus is an effective microbial adsorbent for heavy metal chromium (Gao Yuzhen, 2015). Good materials for biosorption mechanism (Chen Can, 2006); Aspergillus niger can resist heavy metals and has a good ability to enrich heavy metals (Fan Ting, 2012).

To this end, the present invention utilizes Bacillus colloid, Saccharomyces cerevisiae and Aspergillus niger, combined with livestock and poultry manure, farmland straw and kitchen waste, and mixed stacking to prepare a bio-organic fertilizer capable of removing heavy metals, which will effectively reduce the toxicity of heavy metal ions in the soil. At the same time, combined with organic fertilizer to repair the soil, improve the soil structure, promote the absorption of nutrient elements by plants, and achieve the purpose of strengthening plants, enhancing pit stress, increasing crop yield, reducing environmental pollution and ensuring people's health.

A bio-organic fertilizer for repairing heavy metals in soil, comprising the following components by weight:

Preferably, the straw-manure fertilizer includes the following main components:

Preferably, the livestock manure is prepared by mixing chicken manure and cow manure in equal amounts.

A preparation method of a bio-organic fertilizer for repairing heavy metals in soil, comprising the following steps:

(1) Preparation of microbial inoculants

A. The preparation method of Saccharomyces cerevisiae agent: take Saccharomyces cerevisiae strain, add it into 30 ℃ water and stir at constant temperature until it is completely dissolved, the obtained liquid is added to the liquid medium, and after culturing for 4-6 days, the density of the bacteria is detected to reach 1.5-3.1 ×10 ⁹ cfu/mL to obtain Saccharomyces cerevisiae;

B, the preparation method of the Bacillus colloid bacteria agent: get the Bacillus colloid bacteria strain, add it into the water and stir at a constant temperature until it is completely dissolved; the obtained liquid is added to the liquid medium, 150rpm, 30-35 ℃ under constant temperature shaking culture 4 -6d, so that the cell density reaches 6.2-8.3×10 ⁹ cfu/mL to obtain Bacillus colloid bacteria agent;

C, the preparation method of Aspergillus niger: get Aspergillus niger species, add water at constant temperature and stir until completely dissolved, add the obtained liquid to the inorganic salt solution, mix the inorganic salt solution with the ingredients, stir and inoculate, 25- The Aspergillus niger agent is obtained after constant temperature fermentation at 30℃ for 4-6d;

(2) The straw-manure compost is fully decomposed

Take the straw and pulverize it into pieces with a diameter of less than 2mm, add kitchen waste and mix well, then add decomposing agent and livestock and poultry manure, keep the moisture at 60%-70%, control the compost height to 1.5 meters, and control the temperature to 25-35 ℃ Under the condition of 23-26d accumulation and decomposing; then the accumulation and decomposing heat up, so that the temperature reaches 60-70 ℃, and maintains for 2-3d, to obtain decomposed straw-feces compost;

(3) Preparation of bio-organic fertilizer

The straw-fecal fertilizer prepared above is spread out, and after its temperature is lowered to 30-35 ° C, the Bacillus colloid bacteria is evenly mixed, and urea, magnesium sulfate, and activated carbon and borax are added, and fully mixed and fermented for 2- 3d; after the fermentation is completed, add Saccharomyces cerevisiae agent and Aspergillus niger agent to mix evenly, control the temperature to 25°C and ferment again for 2-3d; dry the fermented mixture, measure and bag it to obtain bio-organic fertilizer.

Preferably, the liquid culture medium for Saccharomyces cerevisiae is composed of: 20g peptone, 10g yeast extract, 2g glucose, dissolved in an appropriate amount of double-distilled water, and then add 15ml of 0.2% adenine solution, and set the volume to 1L; 120 Autoclave at ℃ for 15 min.

Preferably, the composition of the liquid culture medium of the Bacillus colloid bacteria agent is: 10 g of sucrose, 0.3 g of yeast extract, 0.5 g of ammonium sulfate, 0.5 g of calcium carbonate, 0.5 g of magnesium sulfate heptahydrate, and dipotassium hydrogen phosphate 1g, adjust the pH to 7.0-7.5 and make up to 1L.

Preferably, the components of the inorganic salt solution are: 1 part of NaCl, 0.5 part of CaCl ₂ , 0.5 part of KCl, 0.5 part of K ₂ HPO ₄ , 0.25 part of NaHCO ₃ , 1 part of MgSO ₄ , FeSO ₄ 7H ₂ O0. 025 parts, 2,000 parts of distilled water; the ingredients are mixed as follows: 2,000 parts of bran, 2,000 parts of bean cake flour, and 1,000 parts of peanut straw powder.

Compared with the prior art, the present invention has the following beneficial effects: the organic matter of the bio-organic fertilizer prepared by the present invention is greater than or equal to 60%, the number of effective viable bacteria is greater than or equal to 050 million/g, and the number of fecal coliforms is less than or equal to 30/g. Compared with ordinary chemical fertilizers (100kg/mu), it can reduce the content of high-value heavy metal ions in soil by more than 8%; reduce the accumulation of heavy metals in crops by more than 10%; especially for the reduction of Cr to more than 70%; increase crop yield by more than 5%, And it has many functions such as water retention, fertilizer retention and soil structure improvement.

Detailed ways

The specific embodiments of the present invention will be further described in detail below with reference to the examples. The following examples are intended to illustrate the present invention, but not to limit the scope of the present invention.

A preparation method of a bio-organic fertilizer for repairing heavy metals in soil, comprising the following steps:

(1) Preparation of microbial inoculum

The preparation method of Saccharomyces cerevisiae inoculum: take 20 strains of Saccharomyces cerevisiae, add 5 times the mass of water at 30°C and stir at constant temperature for 0.5h until completely dissolved, the obtained liquid is added to a liquid medium of 1L volume, and tested after culturing for 5 days The cell density reached 2.2×10 ⁹ cfu/mL.

The components of the liquid medium are: 20g peptone, 10g yeast extract, 2g glucose, dissolved in an appropriate amount of double-distilled water, and then add 15ml of 0.2% adenine solution to make the volume to 1L; autoclave at 120°C for 15min.

The preparation method of Bacillus colloids inoculum: take 20 copies of Bacillus colloids strains, add five times the mass of water at 35°C and stir at constant temperature for 0.5h until completely dissolved; the obtained liquid is added to a 1L volume of liquid medium, 150rpm, constant temperature shaking culture at 32°C for 6 days, so that the cell density reaches 7.8×10 ⁹ cfu/mL.

The composition of the liquid medium is: 10g of sucrose, 0.3g of yeast extract, 0.5g of ammonium sulfate, 0.5g of calcium carbonate, 0.5g of magnesium sulfate heptahydrate, 1g of dipotassium hydrogen phosphate, adjust the pH value to 7.0-7.5 and set the volume to 1L .

The preparation method of the Aspergillus niger agent: take 20 parts of Aspergillus niger species, add five times the mass of water at 30°C and stir at constant temperature for 0.5h until completely dissolved, add the obtained liquid to the inorganic salt solution, mix the inorganic salt solution (NaCl 1g, CaCl ₂ 0.5g, KCl 0.5g, K ₂ HPO ₄ 0.5g, NaHCO ₃ 0.25g, MgSO ₄ 1g, FeSO ₄ 7H ₂ O 25mg, distilled water 2L) mixed with 5kg of ingredients (bran: bean cake flour: peanut Straw powder = 2:2:1) for stirring and inoculation. The Aspergillus niger agent was obtained after 5 days of constant temperature fermentation at 28°C.

(2) The straw-manure compost is fully decomposed

Take the straw and smash it into pieces with a diameter of less than 2mm, add kitchen waste and mix well, then add decomposing agent and livestock and poultry manure, keep the moisture at 60%-70%, control the compost height to 1.5 meters, and control the temperature to 30 ℃. The piles are decomposed for 25 days; then the piles are decomposed and heated up, so that the temperature reaches 60-70 °C and maintained for 2 days to obtain decomposed straw-feces compost;

(3) Preparation of bio-organic fertilizer

The straw-fecal fertilizer prepared above was spread out to make the temperature drop to 30°C, and then evenly mixed with Bacillus colloid bacteria agent, and urea, magnesium sulfate, 0.5% activated carbon and 0.1% borax were added to fully Mix and ferment for 2 days; add 1% of Saccharomyces cerevisiae agent and 1% of Aspergillus niger after the fermentation is completed and mix evenly, control the temperature to 25°C and ferment again for 3 days; dry the fermented mixture, measure and bag it to obtain bio-organic fertilizer.

The bio-organic fertilizer for repairing heavy metals in soil includes the following components by weight:

The straw-manure fertilizer includes the following main components:

The livestock and poultry manure is prepared by mixing chicken manure and cow manure in equal amounts.

The 50% straw includes 20% corn straw, 20% rice straw and 10% wheat straw.

The composition of each weight percentage of the bio-organic fertilizer in each embodiment is shown in the following table:

The composition of each weight percentage of straw-fecal fertilizer in each embodiment is shown in the following table:

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 straw 50 40 45 55 60 65 45 decomposer 1 0.8 0.9 1.5 1.2 1.5 1 kitchen waste 5 3 5 8 7 6 5 livestock manure margin margin margin margin margin margin margin

The bio-organic fertilizer prepared by the present invention is tested to obtain the following data:

The fertilizer of the present invention is applied to rice planting, and the heavy metal treatment effect after one year is tested and compared with ordinary compound fertilizer (N:P ₂ O ₅ :K ₂ O=2:1:3), and the following data are obtained:

Fertilization rate: 100kg/mu, which can reduce the content of high-value heavy metal ions in soil by 8.5-10%; reduce the accumulation of heavy metals in crops by 12-15%; reduce Cr to 75-80%; increase crop yield by 6-8%.

The following is a comparative example, which specifically analyzes the flora in the fertilizer of the present invention.

Comparative Example 1

The Bacillus colloid bacteria in Example 1 was removed, and the effect of heavy metal treatment after one year was tested and compared with ordinary compound fertilizers (N:P ₂ O ₅ :K ₂ O=2:1:3), and the following results were obtained. data:

Fertilization rate: 100kg/mu, which can reduce the content of high-value heavy metal ions in the soil by 2-3%; reduce the accumulation of heavy metals in crops by 3-5%; reduce Cr by 25-30%; increase crop yield by 4-5%.

Comparative Example 2

Saccharomyces cerevisiae in Example 1 was removed, and the heavy metal treatment effect after one year was tested and compared with the common compound fertilizer (N:P ₂ O ₅ :K ₂ O=2:1:3) to obtain the following data:

Fertilization rate: 100kg/mu, which can reduce the content of high-value heavy metal ions in the soil by 2-3%; reduce the accumulation of heavy metals in crops by 2-3%; reduce Cr to 55-60%; increase crop yield by 5-6%.

Comparative Example 3

The Aspergillus niger agent in Example 1 was removed, and the heavy metal treatment effect after one year was tested and compared with the common compound fertilizer (N:P ₂ O ₅ :K ₂ O=2:1:3) to obtain the following data:

Fertilization rate: 100kg/mu, which can reduce the content of high-value heavy metal ions in soil by 3-4%; reduce the accumulation of heavy metals in crops by 6-8%; reduce Cr to 45-50%; increase crop yield by 3-5%.

Comparative Example 4

The Aspergillus niger and Saccharomyces cerevisiae in Example 1 were removed, and the effect of heavy metal treatment after one year was tested and compared with ordinary compound fertilizer (N:P ₂ O ₅ :K ₂ O=2:1:3) , get the following data:

Fertilization rate: 100kg/mu, which can reduce the content of high-value heavy metal ions in soil by 1-2%; reduce the accumulation of heavy metals by crops by 2-3%; reduce Cr by 20-30%; increase crop yield by 3-5%.

From the test data of Comparative Examples 1-4, it can be known that the combined use of three microorganisms is much better than the soil heavy metal remediation effect of using one microorganism or two microorganisms together.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the technical principles of the present invention, several improvements and modifications can also be made. These improvements and modifications It should also be regarded as the protection scope of the present invention.

Claims (4)

1. The biological organic fertilizer for repairing soil heavy metals is characterized by comprising the following components in percentage by weight:

1-3% of Bacillus mucilaginosus fungicide

0.2 to 0.7 percent of urea

Magnesium sulfate 0.05-0.2%

0.3 to 0.8 percent of active carbon

0.08 to 0.15 percent of borax

Saccharomyces cerevisiae 0.5-1.5%

0.7 to 2 percent of Aspergillus niger microbial inoculum

The balance of straw-manure fertilizer;

the straw-excrement fertilizer comprises the following main components:

40 to 65 percent of straw

0.8 to 1.5 percent of decomposition agent

3 to 8 percent of kitchen waste

The rest of the livestock and poultry manure;

the preparation method of the biological organic fertilizer for repairing the heavy metals in the soil comprises the following steps:

(1) preparation of microbial agent

A. The preparation method of the saccharomyces cerevisiae agent comprises the following steps: adding Saccharomyces cerevisiae strain into 30 deg.C water, stirring at constant temperature until completely dissolved, adding the obtained liquid into liquid culture medium, culturing for 4-6d, and detecting thallus density to 1.5-3.1 × 10⁹cfu/mL to obtain a saccharomyces cerevisiae agent;

B. the preparation method of the bacillus mucilaginosus agent comprises the following steps: taking bacillus mucilaginosus strain, adding into water, and stirring at constant temperature until the bacillus mucilaginosus strain is completely dissolved; adding the obtained liquid into liquid culture medium, shake culturing at 150rpm and 30-35 deg.C for 4-6 days to make thallus density reach 6.2-8.3 × 10⁹cfu/mL to obtain the bacillus mucilaginosus agent;

C. the preparation method of the aspergillus niger agent comprises the following steps: adding 20 parts of aspergillus niger strains into water with the mass of 5 times of the aspergillus niger strains, stirring at constant temperature until the aspergillus niger strains are completely dissolved, adding the obtained liquid into an inorganic salt solution, mixing the inorganic salt solution with ingredients, stirring and inoculating, and fermenting at constant temperature of 25-30 ℃ for 4-6 days to obtain an aspergillus niger agent; the inorganic salt solution comprises the following components: 1 part of NaCl, CaCl₂0.5 part, KCl 0.5 part, K₂HPO₄0.5 part of NaHCO₃0.25 part of MgSO 2₄1 part of FeSO₄·7H₂0.025 parts of O and 2000 parts of distilled water; the mixture of the ingredients is as follows: 2000 parts of bran, 2000 parts of bean cake powder and 1000 parts of peanut straw powder;

(2) straw-excrement compost becomes thoroughly decomposed

Crushing straws into powder with the diameter less than 2mm, adding kitchen waste, uniformly mixing, adding a decomposition agent and livestock and poultry manure, keeping the water content at 60-70%, controlling the compost height to be 1.5 m, and stacking for decomposition for 23-26d at the temperature of 25-35 ℃; then stacking, decomposing and heating to make the temperature reach 60-70 ℃, and maintaining for 2-3d to prepare decomposed straw-excrement compost;

(3) preparation of biological organic fertilizer

Spreading and drying the prepared straw-excrement fertilizer, cooling the temperature to 30-35 ℃, uniformly mixing with a bacillus mucilaginosus microbial inoculum, adding urea, magnesium sulfate, active carbon and borax, and fully mixing and fermenting for 2-3 d; after fermentation, adding a saccharomyces cerevisiae microbial inoculum and an aspergillus niger microbial inoculum, uniformly mixing, and controlling the temperature to be 25 ℃ for secondary fermentation for 2-3 d; and drying, metering and bagging the fermented mixture to obtain the biological organic fertilizer.

2. The biological organic fertilizer for remediating heavy metals in soil as claimed in claim 1, wherein the livestock manure is a mixture of chicken manure and cow manure in equal amount.

3. The biological organic fertilizer for remediating soil heavy metals as claimed in claim 1, wherein the saccharomyces cerevisiae liquid culture medium comprises the following components: 20g of peptone, 10g of yeast extract, 2g of glucose and a proper amount of double distilled water are dissolved, 15ml of 0.2% adenine solution is added, and the volume is fixed to 1L; autoclaving at 120 deg.C for 15 min.

4. The biological organic fertilizer for remediating heavy metals in soil as claimed in claim 1, wherein the liquid culture medium of the bacillus mucilaginosus microbial inoculum comprises the following components: 10g of sucrose, 0.3g of yeast extract, 0.5g of ammonium sulfate, 0.5g of calcium carbonate, 0.5g of magnesium sulfate heptahydrate and 1g of dipotassium phosphate, adjusting the pH value to 7.0-7.5 and fixing the volume to 1L.