CN112808767A

CN112808767A - Method for repairing organic matter contaminated soil by cyclodextrin enhanced microorganisms

Info

Publication number: CN112808767A
Application number: CN202011626131.2A
Authority: CN
Inventors: 倪寿清; 段福昂; 崔兆杰; 赵逸昳
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2020-12-30
Filing date: 2020-12-30
Publication date: 2021-05-18

Abstract

The invention relates to a method for repairing organic matter contaminated soil by cyclodextrin enhanced microorganisms, which comprises the steps of dividing and separating the organic matter contaminated soil into regions; uniformly spraying the cyclodextrin water solution on the surface of the divided area soil, ploughing the soil, and then balancing for three days; adding the microbial agent to the balanced soil; then adding an organic fertilizer, and turning over again; and leveling the repair area after ploughing, and spraying water periodically to keep the soil moist. The invention can realize the adsorption and fixation of organic pollutants through beta-cyclodextrin, realize the enrichment around microorganisms, and then efficiently degrade the organic pollutants in soil through the microorganisms. The method solves the problems that the existing single adsorption repairing method has low repairing efficiency, only can be fixed and can not be degraded in situ, and the like, overcomes the defect of low probability of contact between pollutants and microorganisms in the microbial repairing process, and greatly improves the degrading efficiency of the microorganisms.

Description

Method for repairing organic matter contaminated soil by cyclodextrin enhanced microorganisms

Technical Field

The invention relates to a method for remedying organic matter contaminated soil by cyclodextrin-enhanced microorganisms, and belongs to the technical field of soil remediation.

Background

In recent years, industrial enterprises located in cities are moved in a large amount, the industrial enterprises generate a large amount of waste residues, waste water and tail gas floating dust containing pollutants in the production process, wherein the waste residues, the waste water and the tail gas floating dust contain organic compounds and the like, the pollutants can enter industrial areas and peripheral soil through modes of atmospheric sedimentation, waste residue infiltration and the like, and if an efficient and economic soil remediation mode is not adopted, the organic pollutants can permeate underground water or volatilize into the air to cause water body and atmosphere pollution and harm to human health.

The soil microbial remediation technology is to reduce the degree of soil pollution by adsorbing, degrading or converting pollutants in soil by using the action of microbes. Compared with the traditional mode, the microbial remediation technology is a novel soil remediation technology, and the mode has low cost, environmental protection and safety, so that the mode is concerned at present. However, the repair period of the microbial remediation technology is long, and sometimes all pollutants in soil cannot be removed, so how to improve the microbial remediation efficiency is one of the hot spots of the current research in the field.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a method for restoring organic contaminated soil by cyclodextrin enhanced microorganisms, which combines the enrichment and capture of beta-cyclodextrin with the microbial restoration and in-situ degradation of the contaminated soil to realize the targeted enrichment and efficient degradation of refractory organic pollutants such as PAHs and the like.

The invention is realized by the following technical scheme:

a method for remedying organic matter contaminated soil by cyclodextrin enhanced microorganisms comprises the following steps:

(1) dividing and separating the organic matter contaminated soil into areas;

(2) uniformly spraying the cyclodextrin water solution on the surface of the divided area soil, ploughing the soil, and then balancing for three days; the concentration of the cyclodextrin water solution is 1-3%, and the amount of the cyclodextrin water solution sprayed is 0.1-2.5kg of cyclodextrin per square meter of soil;

(3) after the soil sprayed with the cyclodextrin water solution is balanced, the microbial agent is added to the balanced soil;

(4) then adding an organic fertilizer, and turning over again; and leveling the repair area after ploughing, and spraying water periodically to keep the soil moist.

Preferably, in step (1), the area is divided and partitioned by inserting a compression plate into soil of the contaminated area to divide the contaminated area into different areas. Prevent different microorganisms from migrating to influence the repairing effect.

Preferably, according to the invention, the aqueous cyclodextrin solution is sprayed in such an amount that the weight of cyclodextrin per square meter of soil is between 0.1 and 0.5 kg.

The addition amount of cyclodextrin in the light pollution area and the heavy pollution area is 0.144kg/m respectively according to the field pollution degree²And 0.288kg/m²。

According to the invention, the microbial agent is preferably OBT lytic bacteria, OBT deoiling bacteria and mixed bacteria of bacillus subtilis and sphingosine bacillus.

According to the invention, the consumption of OBT lytic bacteria and OBT degreasing bacteria is 140g/m³The amount of mixed bacteria of Bacillus subtilis and Sphingobacterium multivorum is 80-120g/m³。

When the OBT cracking bacteria and the OBT degreasing bacteria are applied, the OBT cracking bacteria and the OBT degreasing bacteria are dissolved respectively according to the proportion of 20g/L water, then glucose and molasses are added and stirred uniformly, and the glucose and the molasses are used as carbon sources to excite the activity of microorganisms; standing for 20 minutes, and then uniformly mixing the two and spraying the mixture on the area to be repaired.

Preferably, in step (4), the amount of organic fertilizer added is 1200-1600kg per hectare.

Preferably, in the step (4), the lightly polluted area is ploughed for 20-40cm, and the heavily polluted area is ploughed for 50-70 cm.

Compared with the prior art, the invention has the following advantages:

the invention can realize the adsorption and fixation of organic pollutants through beta-cyclodextrin, realize the enrichment around microorganisms, and then efficiently degrade the organic pollutants in soil through the microorganisms. The method solves the problems that the existing single adsorption repairing method has low repairing efficiency, only can be fixed and can not be degraded in situ, and the like, overcomes the defect of low probability of contact between pollutants and microorganisms in the microbial repairing process, and greatly improves the degrading efficiency of the microorganisms. The repairing method can effectively repair the polluted soil and reach the relevant standard for subsequent development and utilization. The method can improve the soil quality, is efficient, pollution-free and pollution-free, and has good effect on treating the soil polluted by organic matters.

Drawings

FIG. 1 is a graph showing the effect of the repair after 30 days using the method of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The OBT lytic bacteria, OBT degreasing bacteria, and mixed bacteria of bacillus subtilis and sphingosine bacillus are all products which are commercially available.

Example 1

step 1, inserting a compression plate into soil in a polluted area to divide the polluted area into different areas and prevent different microorganisms from migrating to influence the restoration effect.

And 2, dissolving the beta-cyclodextrin powder in water to prepare a 1% (w/v) aqueous solution. The cyclodextrin dosage is determined according to soil area, the cyclodextrin water solution is sprayed in an amount of 0.1kg of cyclodextrin per square meter of soil, and the cyclodextrin adding amounts of the light pollution area and the heavy pollution area are respectively 0.144kg/m according to the field pollution degree²And 0.288kg/m². The total dosage of the light pollution area and the heavy pollution area is 3.6kg and 7.2kg respectively. And uniformly spraying the prepared aqueous solution on the soil surface of the area divided in advance. Plowing the soil, and then balancing for three days. The beta-cyclodextrin is purchased from the market, and the detection content reaches 99 percent.

Step 3, after the soil added with cyclodextrin is balanced, different types of microbial agents are addedIn the area divided first. The dosage of OBT cracking bacteria and OBT degreasing bacteria is 140g/m³The dosage of the mixed solid microbial inoculum of the bacillus subtilis and the sphingosine bacillus multivorus is 120g/m³. The OBT cracking bacteria and the OBT degreasing bacteria are respectively dissolved according to the proportion of 20g/L water, then a proper amount of glucose and molasses are added and uniformly stirred, and the glucose and the molasses are used as carbon sources for exciting the microbial activity. Standing for 20 minutes, and then uniformly mixing the two and spraying the mixture on the area to be repaired. The mixed solid microbial inoculum of the bacillus subtilis and the sphingosine bacillus multivorus can be directly and uniformly added to another area to be repaired.

And 4, adding a proper amount of organic fertilizer on the soil surface of the polluted area to provide a carbon source for the subsequent growth and propagation of microorganisms and the maintenance of continuous activity. The amount of the organic fertilizer is calculated as 1kg per hectare, and the amount of the organic fertilizer in the light pollution area and the heavy pollution area is 3.75kg according to the field condition.

And 5, ploughing the soil added with the microbial inoculum and the organic fertilizer again. Ploughing the lightly polluted area by 30cm and ploughing the heavily polluted area by 60 cm. And leveling the repair area after ploughing is finished, and removing redundant stones. Meanwhile, the repairing area is sprayed with water regularly, soil is kept moist, and a good growth environment is provided for microorganisms to play a normal repairing role.

After the microbial inoculum and the beta-cyclodextrin are added, planting soybeans and coreopsis on the soil surface, and observing the growth conditions of the coreopsis and the soybeans after one month.

After one month of repair, the growth conditions of soybean and boswellia chrysanthemum were generally good, occasionally, the individual plants withered, and the repair effect is shown in fig. 1.

Example 2

And 2, dissolving the beta-cyclodextrin powder in water to prepare a 3% (w/v) aqueous solution. The amount of cyclodextrin is determined by soil area, and the amount of cyclodextrin water solution is sprayedThe weight of cyclodextrin in soil per square meter is 0.5kg, and the addition amount of cyclodextrin in the light pollution area and the heavy pollution area is 0.144kg/m respectively according to the field pollution degree²And 0.288kg/m². The total dosage of the light pollution area and the heavy pollution area is 3.6kg and 7.2kg respectively. And uniformly spraying the prepared aqueous solution on the soil surface of the area divided in advance. Plowing the soil, and then balancing for three days. The beta-cyclodextrin is purchased from the market, and the detection content reaches 99 percent.

And 3, after the soil added with the cyclodextrin is balanced, adding different types of microbial agents into the areas divided in advance. The consumption of OBT cracking bacteria and OBT degreasing bacteria is 160g/m³The dosage of the mixed solid microbial inoculum of the bacillus subtilis and the sphingosine bacillus multivorus is 100g/m³. The OBT cracking bacteria and the OBT degreasing bacteria are respectively dissolved according to the proportion of 20g/L water, then a proper amount of glucose and molasses are added and uniformly stirred, and the glucose and the molasses are used as carbon sources for exciting the microbial activity. Standing for 20 minutes, and then uniformly mixing the two and spraying the mixture on the area to be repaired. The mixed solid microbial inoculum of the bacillus subtilis and the sphingosine bacillus multivorus can be directly and uniformly added to another area to be repaired.

And 4, adding a proper amount of organic fertilizer on the soil surface of the polluted area to provide a carbon source for the subsequent growth and propagation of microorganisms and the maintenance of continuous activity. The organic fertilizer is calculated according to 1200kg per hectare, and the use amount of the organic fertilizer in a light pollution area and a heavy pollution area is 3.75kg according to the field condition.

While the present invention has been described with reference to the preferred embodiments, it is not intended to limit the invention to the specific embodiments shown. In practical cases, the corresponding modifications and changes can be made according to the content of the specification. The embodiments described above are merely illustrative of the principles and specific applications of the present invention to enable one skilled in the relevant art to better understand and utilize the present method. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for cyclodextrin-enhanced microbial restoration of organic matter-contaminated soil, comprising the steps of:

(1) Divide and separate organic-contaminated soil into regions;

(2) The cyclodextrin aqueous solution is evenly sprayed on the soil surface of the divided area, the soil is tilled, and then balanced for three days; the concentration of the cyclodextrin aqueous solution is 1-3%, and the amount of the The weight of cyclodextrin is 0.1-2.5kg;

(3) after the soil balance of spraying the cyclodextrin aqueous solution, the microbial inoculum is added on the soil after the balance;

(4) Then add organic fertilizer and plough again; after ploughing, level the repaired area, and at the same time sprinkle water regularly to keep the soil moist.

2 . The method according to claim 1 , wherein, in step (1), the area is divided and separated by inserting a compression plate into the soil of the polluted area, so as to divide the polluted area into different areas. 3 .

3. method according to claim 1 is characterized in that, the amount of spraying cyclodextrin aqueous solution makes the weight of cyclodextrin on every square meter of soil be 0.1-0.5kg.

4 . The method according to claim 1 , wherein the dosage of cyclodextrin in the lightly polluted area and the heavily polluted area is 0.144 kg/m ² and 0.288 kg/m ² , respectively. 5 .

5. method according to claim 1, is characterized in that, described microbial inoculum is the mixed bacteria of OBT lytic bacteria, OBT degreasing bacteria and Bacillus subtilis and Sphingosine polyphaga.

6. method according to claim 1 is characterized in that, the consumption of OBT lysing bacteria and OBT degreasing bacteria is respectively 140g/ ^m , and the consumption of the mixed bacteria of Bacillus subtilis and Sphingosine polyphaga is 80-120g /m ³ .

7. method according to claim 1, is characterized in that, in step (4), the dosage of organic fertilizer is 1200-1600kg per hectare.

8. The method according to claim 1, characterized in that, in step (4), plowing 20-40 cm in lightly polluted areas and 50-70 cm in heavily polluted areas.