CN106734183A - A kind of mining area nickel contamination soil remediation method - Google Patents

Abstract

A method for remediating nickel-contaminated soil in a mining area. Firstly, the grid multi-point method is used to collect soil samples, and then the nickel content of the collected soil samples is measured, and the soil is classified into grades according to the measurement results of the soil nickel content, and then plowed for nickel The surface layer of contaminated soil is 10-18cm thick, and then sprinkle the appropriate amount of soil remediation agent and slow-release granules according to the divided soil grade, and finally irrigate the nickel-contaminated land with a water depth of more than 20cm and a relative soil humidity of 85%. above, and keep the relative humidity for 10-20 days. The soil remediation agent is composed of an adsorption carrier and effective live bacteria adsorbed on the carrier. This method has high remediation efficiency, low cost, no secondary pollution, adapts measures to local conditions, can more accurately and quickly remediate nickel-contaminated soil in mining areas, effectively prevents nickel from migrating in the soil, prevents the scope of soil pollution from expanding, and provides long-term protection for the soil during the soil remediation process. Provide nutrients and increase the usable value of the soil.

Description

A method for remediating nickel-contaminated soil in a mining area

technical field

The invention relates to the technical field of soil remediation in mining areas, in particular to a method for remediating nickel-contaminated soil in mining areas.

Background technique

Nickel pollution in the mining area is serious. The nickel-contaminated soil in the mining area in my country is usually used for agricultural use after remediation. If the remediation is not complete, nickel enters the plant through the root system, causing poor plant growth, causing harm to the plant, and even causing plant death. Nickel can accumulate in plants, and when plants with nickel accumulation exceeding normal levels enter the food chain, it will affect the health of animals and even humans.

At present, most of the nickel-contaminated land in my country has not been treated, causing huge hidden dangers to the environment. Soil nickel pollution is concealed, hysteresis and long-term, causing harm to the ecological environment, and nickel is a mobile pollutant. After nickel enters the soil, the scope of polluted soil gradually expands.

Remediation technologies for nickel-contaminated land in the prior art mainly include microbial removal methods, chemical methods (pharmaceutical washing, thermal decomposition, etc.), physical methods (electric current causes charged particles to migrate, etc.) and planting, and a large number of methods are still in laboratory research. At the stage, on-site implementation is difficult. At the same time, the existing nickel-contaminated land treatment technology is relatively backward, resulting in problems of low restoration efficiency, high cost, secondary pollution and environmental risks of nickel-contaminated land.

The land in the mining area is uneven, and the nickel content in the soil varies greatly. Therefore, when the soil is repaired, soil sample collection and analysis are required. When collecting soil samples, the traditional "S" or "diagonal" method is difficult to reflect the actual situation of soil nickel content due to the large difference in soil nickel content. At present, when remediating nickel-contaminated soil, the soil is not fully considered. The spatial variability of nickel content is not considered in the collection and restoration of soil samples, and there are certain deficiencies.

Contents of the invention

In order to solve the above technical problems, the object of the present invention is to provide a method for remediating nickel-contaminated soil in mining areas, which has high remediation efficiency, low cost, no secondary pollution, adapts measures to local conditions, can more accurately and quickly repair nickel-contaminated soil in mining areas, and effectively prevents nickel from Migrate in the soil, prevent the scope of soil pollution from expanding, and provide nutrients for the soil for a long time in the process of soil remediation, and increase the usable value of the soil.

The technical solution adopted in the present invention is: a method for remediating nickel-contaminated soil in a mining area. Firstly, the grid multi-point method is used to collect soil samples, and then the nickel content of the collected soil samples is measured, and according to the soil nickel content measurement results Divide the soil into grades, then plow the soil with a thickness of 10-18 cm on the surface of the nickel-contaminated soil, then sprinkle the appropriate amount of soil remediation agent and slow-release granules according to the grade of the soil, and finally irrigate the nickel-contaminated land with an irrigation depth of Above 20cm, the relative humidity of the soil is above 85%, and the relative humidity can be maintained for 10-20 days. The soil remediation agent is composed of an adsorption carrier and effective live bacteria adsorbed on the carrier, and each gram of soil remediation The total number of effective viable bacteria contained in the agent is (5～150)×10 ⁸ CFU; The ratio of effective viable bacteria of Bacillus plasmodia and Trametes versicolor versicolor is 1.5～2:1～2:2～3.5, and the adsorption carrier is made of coconut bran, diatomaceous earth and bentonite according to the weight ratio of 1:2:1 made by mixing

The slow-release granules are prepared from 120-140 parts of linseed cake, 50-60 parts of peony seed shells, 100-120 parts of straw, 30-40 parts of bamboo charcoal powder and 150-200 parts of modified rice bran protein solution according to the weight ratio. According to the weight ratio, the modified rice bran protein solution is mixed with 10-15 parts of rice bran protein and 100-120 parts of distilled water, followed by adding 0.5 to 1 part of glutamine transaminase and 0.1 to 0.2 parts of potassium diformate at 45 to 50 It can be obtained by heating at ℃ temperature for 2h.

The grid size in the adopted grid multi-point method is (10-45) m×(10-45) m.

The specific preparation method of the sustained-release granules is as follows: weigh flaxseed cake, peony seed shell, straw, bamboo charcoal powder, rice bran protein, distilled water, glutamine transaminase and potassium diformate according to the above weight ratio, and weigh the peony Seed husk and straw are mixed and put into a pulverizer to pulverize into 200-400 mesh powder, the obtained powder is mixed with bamboo charcoal powder and linseed cake, dried, and then placed in a granulator for granulation to obtain mixed granules. Mix rice bran protein with distilled water, add transglutaminase and potassium diformate, heat to 45-50°C, and keep the temperature for 2 hours to obtain a modified rice bran protein solution, and then spray the modified rice bran protein solution onto the mixed particles After drying, the slow-release granules are prepared.

The soil classification according to the soil nickel content measurement results refers to: according to the soil nickel content measurement results, the soil is divided into five grades, the soil nickel content of the first grade soil is lower than 9.5mg/kg, and the soil nickel content of the second grade soil is less than 9.5mg/kg. The content of nickel in the soil is not less than 9.5 mg/kg and lower than 20 mg/kg, the soil nickel content in the third-grade soil is not lower than 20 mg/kg and lower than 38 mg/kg, and the soil nickel content in the fourth-grade soil is not lower than 38 mg/kg. kg and less than 49mg/kg, the soil nickel content of grade 5 soil is not less than 56mg/kg;

The amount of soil remediation agent and slow-release granules applied in the five grades of soil is: when the soil in the grid is first-grade soil, the amount of soil remediation agent is 3-4 kg per mu, and the amount of slow-release granules The amount of application is 250-450kg per mu; when the soil in the grid is secondary soil, the application rate of soil remediation agent is 4-6kg per mu, and the application rate of slow-release granules is 450-650kg per mu; When the soil in the grid is Grade 3 soil, the amount of soil remediation agent applied is 6-8 kg per mu, and the amount of slow-release granules is 650-850 kg per mu; when the soil in the grid is Grade 4 soil, the soil The application rate of the restoration agent is 8-10 kg per mu, and the application rate of the slow-release granules is 850-1050 kg per mu; when the soil in the grid is level five soil, the application rate of the soil restoration agent is 10-10 kg per mu. 12kg, and the spreading rate of slow-release granules is 1050-1250kg per mu.

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

1. The present invention can restore nickel-contaminated soil in a short period of time, improve soil fertility, have high repair efficiency, low cost, no secondary pollution, and can restore the use function of nickel-contaminated soil in coal mine subsidence areas;

2. The grid multi-point sampling method is used to collect soil samples, and the soil remediation agent and slow-release particles are applied in stages, which overcomes the shortcomings of large spatial differences in nickel content in the soil in the mining area, achieves the effect of accurate restoration, and reduces costs. Can quickly and evenly improve soil fertility;

3. Remediate the soil by spreading soil remediation agents and slow-release granules, so that the remediated soil can be used as agricultural land, and can provide effective nutrients for microorganisms and plants;

Four, the soil remediation agent used in the present invention can effectively improve the existence form of nickel in the soil. After using the soil remediation agent to repair the nickel-contaminated soil, the remediation soil can be used as agricultural planting, which can reduce the entry of nickel through the root system. At the same time, the accumulation of nickel in plants is greatly reduced. The adsorption carrier used in the soil remediation agent has excellent permeability, water retention capacity and nutrient supply capacity, and can effectively maintain the activity of effective live bacteria. The soil remediation agent can reduce the activity of nickel in the soil, fix the nickel in the soil, effectively prevent the migration of nickel, and prevent the scope of nickel-contaminated soil from further expanding;

5. The slow-release granules used in the present invention can provide nutrients for the soil and reduce the mobility of nickel particles in the soil. The linseed oil cake in the slow-release granules can provide various elements for the soil, which can effectively improve the physical properties of the soil , to overcome the shortcomings of poor hard physical structure of nickel-contaminated soil in mining areas, the slow-release particles can be decomposed slowly, prolong the action period, rice bran protein is modified under the joint action of glutamine transaminase and potassium diformate, which is conducive to the unfolding of protein molecules, and It catalyzes intramolecular and intermolecular covalent crosslinking of protein polypeptides, which is manifested by increased viscosity, high shear resistance and adhesiveness, so that the prepared modified rice bran protein solution can coat the mixed particles Finally, a slowly decomposing protein layer is formed on the outer layer of the mixed particles to provide nutrients for the soil for a long time;

6. Through the application of soil amendments and slow-release granules, the combination of organic and biological, quick-acting and slow-acting, and complementary advantages can achieve the effect of completely repairing nickel-contaminated soil in coal mine subsidence areas.

Specific implementation

The present invention will be further described below in conjunction with specific examples, and the protection scope of the present invention is not limited to the following examples. The process, conditions, reagents, etc. for implementing the present invention are common knowledge and common knowledge in the art except for the content specifically mentioned below, and the present invention has no special limitation content.

Example 1

A method for remediating nickel-contaminated soil in a mining area, comprising the following steps:

(1) Soil samples were collected using the grid multi-point sampling method, and the collection depth was 10cm;

(2) Measure the nickel content of the collected soil samples, and divide the soil into five grades according to the soil nickel content measurement results. The soil nickel content of the first grade soil is less than 9.5mg/kg, and the soil nickel content of the second grade soil is less than 9.5mg/kg. The content of nickel in the soil is not less than 9.5 mg/kg and lower than 20 mg/kg, the soil nickel content in the third-grade soil is not lower than 20 mg/kg and lower than 38 mg/kg, and the soil nickel content in the fourth-grade soil is not lower than 38 mg/kg. kg and less than 49mg/kg, the soil nickel content of grade 5 soil is not less than 56mg/kg;

(3) Take coconut peat, diatomaceous earth and bentonite according to the weight ratio of 1:2:1 and mix them to make an adsorption carrier. Make soil remediation agent, wherein, the ratio of the effective number of viable bacteria of halomonas, colloid bacillus and Trametes versicolor versicolor is 1.5:1:2, in described soil remediation agent, in every gram of soil remediation agent The total number of effective viable bacteria contained is 5×108CFU;

(4) Mix 10 parts of rice bran protein with 100 parts of distilled water according to the weight ratio, then add 0.5 part of glutamine transaminase and 0.1 part of potassium diformate and heat at 45°C for 2 hours to obtain a modified rice bran protein solution. Weigh 120 parts of linseed cake, 50 parts of peony seed shells, 100 parts of straw, 30 parts of bamboo charcoal powder and 150 parts of modified rice bran protein solution, mix the weighed peony seed shells and straws, put them into a grinder and grind them into 200-mesh powder, mix the obtained powder with bamboo charcoal powder and linseed cake, dry it, then place it in a granulator to granulate to obtain mixed granules, and finally spray the modified rice bran protein solution on the mixed granules, and dry them Afterwards, slow-release granules are prepared;

(5) Plow the soil with a thickness of 10 cm on the surface of the nickel-contaminated soil, and apply the appropriate amount of soil remediation agent and slow-release particles according to the divided soil grade. The spreading rate is 3kg per mu, and the spreading rate of slow-release granules is 250kg per mu; when the soil in the grid is secondary soil, the spreading rate of soil remediation agent is 4kg per mu, and the spreading rate of slow-release granules is 450kg per mu; when the soil in the grid is grade 3 soil, the amount of soil remediation agent applied is 6kg per mu, and the amount of slow-release granules is 650kg per mu; when the soil in the grid is grade 4 soil, The application rate of soil remediation agent is 8kg per mu, and the application rate of slow-release granules is 850kg per acre; The amount of application is 1050kg per mu;

(6) Irrigate the nickel-contaminated land with a water depth of more than 20cm and a relative soil humidity of more than 85%, and maintain this relative humidity for 10 days.

In this embodiment, the grid size in step (1) is 10m×10m.

Example 2

A method for remediating nickel-contaminated soil in a mining area, comprising the following steps:

(1) Soil samples were collected using the grid multi-point sampling method, and the collection depth was 14cm;

(2) Measure the nickel content of the collected soil samples, and divide the soil into five grades according to the soil nickel content measurement results. The soil nickel content of the first grade soil is less than 9.5mg/kg, and the soil nickel content of the second grade soil is less than 9.5mg/kg. The content of nickel in the soil is not less than 9.5 mg/kg and lower than 20 mg/kg, the soil nickel content in the third-grade soil is not lower than 20 mg/kg and lower than 38 mg/kg, and the soil nickel content in the fourth-grade soil is not lower than 38 mg/kg. kg and less than 49mg/kg, the soil nickel content of grade 5 soil is not less than 56mg/kg;

(3) Take coconut peat, diatomaceous earth and bentonite according to the weight ratio of 1:2:1 and mix them to make an adsorption carrier. Make soil remediation agent, wherein, the ratio of the effective number of viable bacteria of halomonas, colloid bacillus and Trametes versicolor is 1.5:2:3, in the described soil remediation agent, in every gram of soil remediation agent The total number of effective viable bacteria contained is 80×108CFU;

(4) Mix 13 parts of rice bran protein with 110 parts of distilled water according to the weight ratio, then add 0.7 parts of glutamine transaminase and 0.15 parts of potassium diformate and heat at 47°C for 2 hours to obtain a modified rice bran protein solution, and then according to the weight ratio Weigh 130 parts of linseed cake, 55 parts of peony seed shells, 110 parts of straw, 35 parts of bamboo charcoal powder and 175 parts of modified rice bran protein solution, mix the weighed peony seed shells and straws, put them into a grinder and grind them into 300-mesh powder, mix the obtained powder with bamboo charcoal powder and linseed cake, dry it, then place it in a granulator to granulate to obtain mixed granules, and finally spray the modified rice bran protein solution on the mixed granules, and dry them Afterwards, slow-release granules are prepared;

(5) Plow the soil with a thickness of 14 cm on the surface of the nickel-contaminated soil, and apply the appropriate amount of soil remediation agent and slow-release particles according to the divided soil grade. The spreading rate is 3.5 kg per mu, and the spreading rate of slow-release granules is 350 kg per mu; when the soil in the grid is secondary soil, the spreading rate of soil remediation agent is 5 kg per mu, and the spreading rate of slow-release granules 550kg per mu; when the soil in the grid is grade 3 soil, the application rate of soil remediation agent is 7kg per mu, and the application rate of slow-release granules is 750kg per mu; when the soil in the grid is grade 4 soil , the application rate of soil remediation agent is 9kg per acre, and the application rate of slow-release granules is 950kg per acre; when the soil in the grid is grade five soil, the application rate of soil remediation agent is 11kg per acre, The application rate of granules is 1150kg per mu;

(6) Irrigate the nickel-contaminated land with a water depth of more than 20cm and a relative soil humidity of more than 85%, and maintain this relative humidity for 15 days.

In this embodiment, the grid size in step (1) is 25m×25m.

Example 3

A method for remediating nickel-contaminated soil in a mining area, comprising the following steps:

(1) Soil samples were collected using the grid multi-point sampling method, and the collection depth was 18cm;

(2) Measure the nickel content of the collected soil samples, and divide the soil into five grades according to the soil nickel content measurement results. The soil nickel content of the first grade soil is less than 9.5mg/kg, and the soil nickel content of the second grade soil is less than 9.5mg/kg. The content of nickel in the soil is not less than 9.5 mg/kg and lower than 20 mg/kg, the soil nickel content in the third-grade soil is not lower than 20 mg/kg and lower than 38 mg/kg, and the soil nickel content in the fourth-grade soil is not lower than 38 mg/kg. kg and less than 49mg/kg, the soil nickel content of grade 5 soil is not less than 56mg/kg;

(3) Take coconut peat, diatomaceous earth and bentonite according to the weight ratio of 1:2:1 and mix them to make an adsorption carrier. Make soil remediation agent, wherein, the ratio of the effective number of viable bacteria of halomonas, colloid bacillus and Trametes versicolor is 2: 2: 3.5, in the described soil remediation agent, in every gram of soil remediation agent The total number of effective viable bacteria contained is 150×108CFU;

(4) Mix 15 parts of rice bran protein with 120 parts of distilled water according to the weight ratio, then add 1 part of glutamine transaminase and 0.2 parts of potassium diformate and heat at 50°C for 2 hours to obtain a modified rice bran protein solution, and then mix according to the weight ratio Weigh 140 parts of linseed cake, 60 parts of peony seed shells, 120 parts of straw, 40 parts of bamboo charcoal powder and 200 parts of modified rice bran protein solution, mix the weighed peony seed shells and straws, put them into a grinder and grind them into 400-mesh powder, mix the obtained powder with bamboo charcoal powder and linseed cake, dry it, then place it in a granulator to granulate to obtain mixed granules, and finally spray the modified rice bran protein solution on the mixed granules, and dry them Afterwards, slow-release granules are prepared;

(5) Plow the soil with a thickness of 18 cm on the surface of nickel-contaminated soil, and apply the appropriate amount of soil remediation agent and slow-release particles according to the divided soil grade. The spreading rate is 4kg per mu, and the spreading rate of slow-release granules is 450kg per mu; when the soil in the grid is secondary soil, the spreading rate of soil remediation agent is 6kg per mu, and the spreading rate of slow-release granules is 650kg per mu; when the soil in the grid is grade 3 soil, the amount of soil remediation agent applied is 8kg per mu, and the amount of slow-release granules is 850kg per mu; when the soil in the grid is grade 4 soil, The application rate of soil remediation agent is 10kg per mu, and the application rate of slow-release granules is 1050kg per acre; The amount of application is 1250kg per mu;

(6) Irrigate the nickel-contaminated land with a water depth of more than 20cm and a relative soil humidity of more than 85%, and maintain this relative humidity for 20 days.

In this embodiment, the grid size in step (1) is 45m×45m.

Claims (5)

1. a kind of mining area nickel contamination soil remediation method, carries out collecting soil sample using grid multipoint method first, then to institute The nickel content of the pedotheque of collection is measured, and then turns over soil divided rank according to soil nickel content measurement result The soil of 10~18cm of nickel contamination upper soll layer thickness is ploughed, the soil remediation to application amount is applied further according to the soil degree for being divided Agent and slow-releasing granules, finally irrigate nickel contamination soil, water irrigating depth be more than 20cm, relative moisture of the soil up to 85% with On, and keep the relative humidity 10~20 days, it is characterised in that：The soil-repairing agent is by absorption carrier and is adsorbed in Effective viable bacteria on the carrier constitutes, and the effective total viable count contained in every gram of soil-repairing agent is（5~150）× 10⁸CFU；Effective viable bacteria is made up of the mixing of Halomonas, colloid bacillus and rainbow conk keyhole bacterium, and Halomonas, glue The living bacteria count ratio of matter bacillus and rainbow conk keyhole bacterium is 1.5~2：1~2：2~3.5, the absorption carrier is by coconut palm Chaff, diatomite and bentonite compare 1 according to weight：2：1 is mixed；

The slow-releasing granules are by 120~140 parts of Flaxseed cakes, 50~60 parts of peony seeds shells, 100~120 according to weight ratio Part stalk, 30~40 parts of bamboo charcoal powders and 150~200 parts of modified rice bran protein solution are made, and the modified rice bran protein solution is pressed It is to sequentially add 0.5~1 part of glutamine after being mixed with 100~120 parts of distilled water by 10~15 parts of rice bran proteins according to weight ratio Transaminase and 0.1~0.2 part of potassium diformate heat 2h at a temperature of 45~50 DEG C and are obtained.

2. a kind of mining area nickel contamination soil remediation method as claimed in claim 1, it is characterised in that：The grid multiple spot for being used Size of mesh opening in method is（10~45）m×（10~45）m.

3. a kind of mining area nickel contamination soil remediation method as claimed in claim 1, it is characterised in that：The tool of the slow-releasing granules Preparation is：Flaxseed cake, peony seeds shell, stalk, bamboo charcoal powder, rice bran are weighed according to weight ratio described in claim 1 Albumen, distilled water, glutamine transaminage and potassium diformate, are put into pulverizer after peony seeds shell and the stalk mixing that will be weighed It is the powder of 200~400 mesh to crush, and the powder that will be obtained is dried after mixing with bamboo charcoal powder, Flaxseed cake, is subsequently placed in granulation Granulated in machine, obtain hybrid particles, then take addition glutamine transaminage and potassium diformate after rice bran protein and distilled water mixing And it is heated to 45~50 DEG C, and keep the temperature 2 hours, obtain modified rice bran protein solution, then by the spray of modified rice bran protein solution It is coated onto on hybrid particles, slow-releasing granules is obtained after drying.

4. a kind of mining area nickel contamination soil remediation method as claimed in claim 1, it is characterised in that described to contain according to soil nickel Measure measurement result refers to by soil divided rank：According to soil nickel content measurement result, soil is divided into five grades, one-level The soil nickel content of soil is less than 9.5mg/kg, and the soil nickel content of second grade soil is not less than 9.5mg/kg and less than 20 mg/ Kg, the soil nickel content of three-level soil is not less than 20 mg/kg and less than 38 mg/kg, and the soil nickel content of level Four soil is not low In 38mg/kg and less than 49mg/kg, the soil nickel content of Pyatyi soil is not less than 56mg/kg.

5. a kind of mining area nickel contamination soil remediation method as claimed in claim 4, it is characterised in that the soil of five grades Soil-repairing agent and sustained release grain amount applied in earth are：When soil in grid is one-level soil, soil-repairing agent is applied The amount of spreading is every mu of 3~4kg, and the amount of applying of slow-releasing granules is every mu of 250~450kg；When soil in grid is second grade soil, soil The amount of applying of earth renovation agent is every mu of 4~6kg, and the amount of applying of slow-releasing granules is every mu of 450~650kg；Soil in grid is During three-level soil, the amount of applying of soil-repairing agent is every mu of 6~8kg, and the amount of applying of slow-releasing granules is every mu of 650~850kg；Net When soil in lattice is level Four soil, the amount of applying of soil-repairing agent is every mu of 8~10kg, and the amount of applying of slow-releasing granules is every mu 850~1050kg；When soil in grid is Pyatyi soil, the amount of applying of soil-repairing agent is every mu of 10~12kg, sustained release The amount of applying of grain is every mu of 1050~1250kg.