CN112342031A - Soil composite modifier and application thereof - Google Patents

Abstract

The invention discloses a soil composite modifier and application thereof, wherein the soil composite modifier comprises the following raw materials in percentage by mass: 10-20% of activated sludge, 10-20% of fulvic acid, 10-20% of charcoal, 1-5% of microbial agent, 10-20% of calcium bentonite, 5-10% of zeolite, 20-30% of sulfate reducing bacteria liquid and 20-30% of organic fertilizer agent. The composite modifier for the building rubbish polluted soil prepared by the invention can improve the soil alkalization problem caused by disordered stacking and landfill of the building rubbish, can adsorb heavy metals in the building rubbish and heavy metals in deep soil, has good effect on removing heavy metal ion pollution, meets the requirement suitable for plant growth, and can be used for alkaline soil remediation, remediation of heavy metal pollution in the soil caused by disordered stacking and landfill of the building rubbish and remediation of deep soil pollution.

Description

Soil composite modifier and application thereof

Technical Field

The invention relates to the field of soil improvement, in particular to a soil composite improver and application thereof.

Background

In recent years, the industrialized development of China is rapid, and simultaneously, all industries are driven to develop rapidly, wherein the development momentum of the construction industry is not quite different, but the increasing quantity of the construction waste follows, according to the measurement of relevant industry associations, the yield of the construction waste in China is over 20 hundred million tons, and accounts for about 40 percent of the total quantity of the municipal waste, so that the construction waste becomes the most huge solid waste in the municipal waste. At present, the construction waste is treated by adopting modes of landfill, open-air stacking, outward transportation and the like in China, the traditional treatment modes can not reduce the harm to the environment, and the harm is mainly shown in the following aspects that (1) a large amount of land is occupied. China is a country with a large population, the population density is quite large, the contradiction between population and land is aggravated because the construction waste is stacked and occupies a large amount of land, and if the construction waste is not treated in time, the problem that the construction waste occupies the land is more serious; (2) the water body and the soil are polluted, the building rubbish is washed by rainwater, the generated leachate is generally strong in alkalinity and contains a large amount of heavy metal ions, the surface water and the underground water are polluted along with the infiltration of the rainwater into the ground, the physical structure and the chemical property of the soil are changed due to the alkalinity of the leachate, the soil is salinized, and the plant growth is influenced; (3) air pollution, lignin and tannic acid can be dissolved out from waste wood in the construction waste under anaerobic condition and decomposed into volatile organic acid, and the volatile organic acid is discharged into the air to pollute the atmosphere.

In the face of the threat of construction waste to the environment, researchers in China make many relevant researches, and at present, the most researches are the problems of soil pollution caused by heavy metal ions in the construction waste and soil alkalization. Aiming at the problem of soil salinization, biological measures, chemical measures, physical measures and three measures are mainly combined at present, and relevant adjustment needs to be made aiming at various factors such as different geographic environments, soil properties and the like, but the difficulty is high, and the operation is complex; the fertilizer for improving alkaline soil is used, but the improvement effect is poor, the soil is hardened, the water retention effect is poor, and the adverse effect on the growth of crops is caused; the method for repairing the soil pollution caused by the heavy metal ions, namely removing the heavy metal ions in the soil, changing the existence form of the heavy metal in the soil and providing three repairing types of physics, chemistry and biology can cause the defects that the heavy metal ions can not be completely removed, only one kind of metal ions can be substituted into other pollutants and the like.

Disclosure of Invention

Aiming at the defects, the sulfate reducing bacteria liquid is used for carrying out anaerobic reaction in the deep layer of the soil to change the existence form of heavy metal ions, meanwhile, activated sludge and charcoal are adopted to adsorb the heavy metal ions, fulvic acid is used to reduce the alkalinity of the soil, and organic fertilizer and microbial agent are used to provide nutrient substances for the growth of plants, so that the problems of heavy metal pollution and alkalization of the soil caused by disordered stacking and burying of construction waste are effectively solved, the heavy metal in the construction waste and the heavy metal in the deep layer of the soil can be adsorbed, the requirements suitable for plant growth are met, and the method can be used for alkaline soil remediation, remediation of heavy metal pollution in the soil caused by disordered stacking and burying of the construction waste and remediation of deep soil pollution.

In order to solve the technical problems, the invention provides the following technical scheme:

a soil composite modifier comprises the following raw materials in percentage by mass: 10-20% of activated sludge, 10-20% of fulvic acid, 10-20% of charcoal, 1-5% of microbial agent, 10-20% of calcium bentonite, 5-10% of zeolite, 20-30% of sulfate reducing bacteria liquid and 20-30% of organic fertilizer agent.

Further, the charcoal is obtained by reacting the crops at 520-580 ℃ under the anoxic condition.

Further, the microbial agents include: phosphate solubilizing bacteria, actinomycetes, bacillus, azotobacter and trichoderma.

Further, the mass ratio of the phosphate solubilizing bacteria, the actinomycetes, the bacillus, the azotobacter and the trichoderma is 2: 2: 1: 1: 1.

further, the sulfate-reducing bacteria bacterial liquid is obtained by culturing sulfate-reducing bacteria under anaerobic conditions.

Further, the culture conditions are as follows: culturing at 28-35 deg.C and pH 6-6.5 in dark under sterile condition for 20-30 days.

The invention also provides a preparation method of the soil composite modifier, which comprises the following steps:

weighing the activated sludge, the fulvic acid, the charcoal, the microbial agent, the calcium bentonite, the heulandite and the sulfate reducing bacteria liquid according to the mass, stirring, adding the organic fertilizer agent, and continuously stirring to obtain a mixture, thereby obtaining the soil composite modifier.

Further, the organic fertilizer agent is subjected to harmless treatment before use.

Further, the harmless treatment steps are as follows:

a. drying human excrement and animal excrement to water content of 25-35%;

b. cutting rice straw, stalk, etc. into bulk and catalytic matter;

c. the weight ratio of the excrement to the leavening and the catalytic substance is 1: 8, mixing and uniformly stirring;

d. delivering the mixed organic fertilizer into a disinfection room for disinfection, wherein the disinfectant is DCW hypochlorous acid; controlling the temperature in the disinfection chamber at 70-90 deg.C, performing primary disinfection for 15-20min, and spraying water at variable time to keep the water content of the organic fertilizer at 25-35%; turning over once in seven days, wherein the composting time is one month;

e. the sterilizing chamber is provided with an exhaust device and a deodorizing device for deodorizing the gas volatilized by the excrement and then discharging the gas into the atmosphere.

The invention also provides application of the soil composite improver in improving the construction waste polluted soil.

Further, when the soil composite improver is used, the soil composite improver and the construction waste polluted soil are mixed according to the weight ratio of 1: 50, mixing to obtain a mixture, and putting the mixture into soil with the depth of 2-10 meters.

Compared with the prior art, the invention has the beneficial effects that:

the invention uses microbial agent and organic fertilizer. The organic fertilizer is subjected to harmless treatment, harmful bacteria such as escherichia coli, insect eggs and the like are removed, the influence on the growth of plants is prevented, the nutrient elements are more, the soil can be improved, the hardening is prevented, and the disease and insect resistance of the plants is improved. Phosphate solubilizing bacteria and nitrogen fixing bacteria in the microbial agent can improve soil properties, improve the utilization rate of the organic fertilizer and promote plant growth; the bacillus and the trichoderma are mainly used for preventing plants from being affected by insect pests, and the actinomycetes decompose complex and decay-resistant compounds in soil. The bacillus and the trichoderma in the microbial agent prevent fungi, bacteria and other fungi from appearing in the organic fertilizer agent and kill harmful fungi and insects in soil in time. The phosphate solubilizing bacteria, trichoderma, actinomycetes and the organic fertilizer agent act together to promote the release of more nutrient elements into soil, and provide an environment with rich nutrition and no insect damage for plant growth.

The fulvic acid used in the invention can promote the ion exchange between the heulandite and the calcium bentonite and the soil, and the fulvic acid improves the soil structure, accelerates the exchange of the heulandite and the calcium bentonite for sodium ions with the soil, and reduces the sodium ions in the soil, thereby reducing the salinity in the soil, improving the alkaline problem of the soil and preventing the soil from hardening. The pH value of the soil is reduced under the combined action of the heulandite and the fulvic acid.

The present invention uses activated sludge and charcoal. Microorganisms in the activated sludge can effectively improve the ecological environment of soil, and the mass propagation of the microorganisms can realize the adsorption of heavy metals; charcoal is used as a carrier medium, microorganisms in the activated sludge carry the charcoal to enter soil, and the charcoal and the heavy metal in the soil react together to adsorb the heavy metal in the soil.

The sulfate reducing bacteria liquid used in the invention is obtained by culturing under the anaerobic condition, wherein the temperature is controlled at 28-35 ℃, the pH is 6-6.5, and the culture is carried out under the dark and sterile condition, and the growth of the sulfate reducing bacteria can be promoted under the dark condition; the purity of sulfate reducing bacteria is ensured in an aseptic manner; temperature and pH provide a suitable growth environment. The sulfate-reducing bacteria cultured under such conditions have a long-lasting action and a high viability. According to the invention, charcoal is used as a medium, sulfate reducing bacteria liquid is adsorbed to enter the deep layer of soil, hydrogen sulfide generated in the sulfate reducing bacteria liquid reacts with metal ions to generate insoluble metal sulfides, heavy metals are removed, and meanwhile, extracellular polymers of the sulfate reducing bacteria can adsorb the heavy metal ions. The sulfate reducing bacteria can remove common heavy metal ions such as Zn, Al, Mn, Cd, Cu and the like.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The specification and examples are exemplary only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

The following examples of the invention use materials selected from:

1. activated sludge: the laboratory carries out aeration, culture and domestication operations on the sewage to obtain the activated sludge.

2. Fulvic acid: purchased from Beijing Bowei Shennong science and technology Co.

3. Charcoal: the material is obtained by carrying out slow pyrolysis on wood, straw and straw at the temperature of 520-580 ℃.

4. And (3) microbial agent: the composite microbial inoculum comprises phosphate solubilizing bacteria, actinomycetes, bacillus, azotobacter and trichoderma, wherein the number of the viable bacteria of the phosphate solubilizing bacteria is 150, the number of the viable bacteria of the actinomycetes is 150, the number of the viable bacteria of the bacillus is 75, the number of the viable bacteria of the azotobacter is 75 and the number of the viable bacteria of the trichoderma is 75.

5. Calcium bentonite: purchased from a firm city yuan heng water purification materials factory.

6. Flake zeolite: purchased from Ministry of Water purification materials of Zhanjin Koufeng Yuan, Jianyi.

7. Sulfate reducing bacteria liquid: the sulfate reducing bacteria are cultured for 20-30 days under the anaerobic condition, the temperature is controlled at 28-35 ℃, the pH value is 6-6.5 and the dark and sterile condition, and the culture medium is a special culture medium for the sulfate reducing bacteria.

8. The harmless treatment steps of the organic fertilizer agent are as follows:

f. drying human excrement and animal excrement to water content of 25-35%;

g. cutting rice straw, stalk, etc. into bulk and catalytic matter;

h. the weight ratio of the excrement to the leavening and the catalytic substance is 1: 8, mixing and uniformly stirring;

i. delivering the mixed organic fertilizer into a disinfection room for disinfection, wherein the disinfectant is DCW hypochlorous acid; controlling the temperature in the disinfection chamber at 70-90 deg.C, performing primary disinfection for 15-20min, and spraying water at variable time to keep the water content of the organic fertilizer at 25-35%; turning over once in seven days, wherein the composting time is one month;

j. the sterilizing chamber is provided with an exhaust device and a deodorizing device for deodorizing the gas volatilized by the excrement and then discharging the gas into the atmosphere.

Example 1

Weighing 10% of activated sludge, 20% of fulvic acid, 10% of charcoal, 5% of microbial agent, 10% of calcium bentonite, 5% of sheet zeolite and 20% of sulfate reducing bacteria liquid according to the mass percentage, mixing, stirring uniformly, adding 20% of organic fertilizer agent, and continuously mixing uniformly to obtain the soil composite modifier. The composite modifier and the construction waste polluted soil are mixed according to the mass ratio of 1: 50 into 2m deep soil. Plants are planted in the soil, and the plants are fertilized, loosened, watered, etc. according to the normal planting method.

Example 2

The difference from example 1 is that the mixture of the composite improver and the construction waste contaminated soil was thrown into soil having a depth of 5 m.

Example 3

The difference from example 1 is that the composite improver and soil mixture was thrown into soil having a depth of 10 m.

Example 4

Weighing 10% of activated sludge, 10% of fulvic acid, 10% of charcoal, 5% of microbial agent, 10% of calcium bentonite, 5% of sheet zeolite and 30% of sulfate reducing bacteria liquid according to the mass percentage, mixing, stirring uniformly, adding 20% of organic fertilizer agent, continuously mixing uniformly to obtain a soil composite modifier, mixing the composite modifier with the construction waste contaminated soil according to the mass ratio of 1: 50 into soil of 5m depth. Plants are planted in the soil, and the plants are fertilized, loosened, watered, etc. according to the normal planting method.

Example 5

Weighing 20% of activated sludge, 20% of fulvic acid, 10% of charcoal, 5% of microbial agent, 10% of calcium bentonite and 5% of sheet zeolite according to the mass percentage, mixing, stirring uniformly, adding 30% of organic fertilizer agent, and continuously mixing uniformly to obtain the soil composite modifier. The composite modifier and the construction waste polluted soil are mixed according to the mass ratio of 1: 50 into soil of 5m depth. Plants are planted in the soil, and the plants are fertilized, loosened, watered, etc. according to the normal planting method.

Comparative example 1

The difference from example 1 is that 10% of the activated sludge was replaced with 10% of the sulfate-reducing bacteria suspension.

Comparative example 2

The difference from example 1 is that the microbial agent is replaced by commercial EM microbial agent, which mainly comprises photosynthetic bacteria, lactic acid bacteria, yeast and fermentation filamentous bacteria.

Comparative example 3

The difference from example 1 is that charcoal was replaced with a sulfate-reducing bacteria solution.

Comparative example 4

The difference from example 1 is that the heulandite was replaced by an organic fertilizer.

Comparative example 5

The difference from example 1 is that calcium bentonite was replaced with sodium bentonite.

After 60 days, the data after calculation of the growth condition of the plants and the detection of heavy metal ions in the soil are shown in tables 1-3:

TABLE 1

	Growth conditions of plants	Removal rate of heavy metal ion (%)
			Example 1(2m)	Is normal	76
Example 2(5m)	Is normal	69
			Example 3(10m)	Is normal	55

TABLE 2

TABLE 3

	Growth conditions of plants	Removal rate of heavy metal ion (%)
			Example 1	Is normal	76
Comparative example 1	Is normal	44
			Comparative example2	Short and small plants with insect pest	70
Comparative example 3	Is normal	38
			Comparative example 4	Plants are short and yellow	69
Comparative example 5	Plant dwarfing	50

Example 6

Weighing 10% of activated sludge, 10% of charcoal, 5% of microbial agent, 20% of calcium bentonite, 10% of sheet zeolite and 25% of sulfate reducing bacteria liquid according to the mass percentage, mixing, stirring uniformly, adding 20% of organic fertilizer agent, and continuously mixing uniformly to obtain the soil composite modifier. The composite modifier and the construction waste polluted soil are mixed according to the mass ratio of 1: 50 into 2m deep soil. Plants are planted in the soil, and the plants are fertilized, loosened, watered, etc. according to the normal planting method.

Example 7

Weighing 10% of activated sludge, 20% of fulvic acid, 10% of charcoal, 5% of microbial agent, 15% of calcium bentonite and 20% of sulfate reducing bacteria liquid according to the mass percentage, mixing, stirring uniformly, adding 20% of organic fertilizer agent, and continuously mixing uniformly to obtain the soil composite modifier. The composite modifier and the construction waste polluted soil are mixed according to the mass ratio of 1: 50 into 2m deep soil. Plants are planted in the soil, and the plants are fertilized, loosened, watered, etc. according to the normal planting method.

Example 8

Weighing 10% of activated sludge, 20% of fulvic acid, 10% of charcoal, 5% of microbial agent, 10% of flat zeolite and 25% of sulfate reducing bacteria liquid according to the mass percentage, mixing, stirring uniformly, adding 20% of organic fertilizer agent, and continuously mixing uniformly to obtain the soil composite modifier. The composite modifier and the construction waste polluted soil are mixed according to the mass ratio of 1: 50 into 2m deep soil. Plants are planted in the soil, and the plants are fertilized, loosened, watered, etc. according to the normal planting method.

After 60d, the pH value and the permeability of the soil (the soil permeability is high, salt on the surface layer of the soil can permeate into the deep layer, and the surface soil can not be hardened) are measured, and the detection data are shown in the table 4:

TABLE 4

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included therein.

Claims (10)

1. The soil composite improver is characterized by comprising the following raw materials in percentage by mass: 10-20% of activated sludge, 10-20% of fulvic acid, 10-20% of charcoal, 1-5% of microbial agent, 10-20% of calcium bentonite, 5-10% of zeolite, 20-30% of sulfate reducing bacteria liquid and 20-30% of organic fertilizer agent.

2. The soil conditioner according to claim 1, wherein said charcoal is obtained by reacting the crops at 520-580 ℃ under anoxic conditions.

3. The soil amendment according to claim 1, wherein the microbial agent comprises: phosphate solubilizing bacteria, actinomycetes, bacillus, azotobacter and trichoderma.

4. The soil composite improver as recited in claim 3, wherein the mass ratio of said phosphate solubilizing bacteria, said actinomycetes, said bacillus, said azotobacter and said trichoderma is 2: 2: 1: 1: 1.

5. the soil conditioner according to claim 1, wherein said sulfate-reducing bacteria solution is obtained by culturing sulfate-reducing bacteria under anaerobic conditions.

6. A soil amendment according to claim 5, characterized in that the culture conditions are: culturing at 28-35 deg.C and pH 6-6.5 in dark under sterile condition for 20-30 days.

7. The soil conditioner according to claim 1, wherein said organic fertilizer is subjected to a detoxification treatment before use.

8. A composite soil conditioner according to claim 7, wherein said detoxification treatment step comprises:

a. drying human excrement and animal excrement to water content of 25-35%;

b. cutting rice straw, stalk, etc. into bulk and catalytic matter;

c. the weight ratio of the excrement to the leavening and the catalytic substance is 1: 8, mixing and uniformly stirring;

d. delivering the mixed organic fertilizer into a disinfection room for disinfection, wherein the disinfectant is DCW hypochlorous acid; controlling the temperature in the disinfection chamber at 70-90 deg.C, performing primary disinfection for 15-20min, and spraying water at variable time to keep the water content of the organic fertilizer at 25-35%; turning over once in seven days, wherein the composting time is one month;

e. the sterilizing chamber is provided with an exhaust device and a deodorizing device for deodorizing the gas volatilized by the excrement and then discharging the gas into the atmosphere.

9. Use of a soil conditioner according to any one of claims 1 to 8 for conditioning soil contaminated with construction waste.

10. The application of claim 9, wherein the soil conditioner composition is mixed with the construction waste contaminated soil according to the weight ratio of 1: 50, mixing to obtain a mixture, and putting the mixture into soil with the depth of 2-10 meters.