CN109718498B - Method for solidifying heavy metal in coal gangue by using microorganisms - Google Patents

Abstract

A method for solidifying heavy metal in coal gangue by using microorganism comprises the following steps: measuring the content of heavy metal ions in the gangue to be filled, selecting strains according to the measurement result, and preparing into a microbial inoculum; arranging a bacterium injection pipe in the goaf; during filling, spraying a microbial inoculum to the gangue through a spray head, and carrying out curing treatment; after filling, spraying bacteria to the accumulated water through a bacteria injection pipeline to realize secondary curing. According to the method for curing the heavy metal in the coal gangue by using the microorganisms, the microorganism is attached before the gangue is filled, so that the heavy metal in the gangue in a goaf can be directly cured; after filling, when accumulated water exists in the goaf, the bacterium injection net can be used for supplementing the bacterium agent, so that secondary curing is realized, migration pollution of heavy metal ions is reduced, the curing effect is good, the pollution is small, and the implementation and popularization are easy.

Description

Method for solidifying heavy metal in coal gangue by using microorganisms

Technical Field

The invention relates to the fields of mining engineering, microorganisms, chemistry and the like, in particular to a method for solidifying heavy metal in coal gangue by using microorganisms.

Background

The coal gangue is a waste discharged in the coal mining, washing and processing processes, and accounts for about 15 percent of the coal yield. Coal gangue has become the solid waste with the largest discharge amount (about 1/4 of industrial solid waste in China), the largest occupation area and serious pollution in various industrial waste residues in China. At present, the comprehensive utilization rate of coal gangue in China is only 30%. The gangue filling technology is a method for processing gangue, but the gangue needs to be processed to prevent pollution.

Disclosure of Invention

The invention aims to provide a method for solidifying heavy metal in coal gangue by using microorganisms, which utilizes the microorganisms to treat the coal gangue so as to prevent the pollution of the heavy metal in the coal gangue.

In order to achieve the above purpose, the technical scheme of the invention is as follows:

a method for solidifying heavy metal in coal gangue by using microorganisms comprises the following steps:

s1: measuring the content of heavy metal ions in the gangue to be filled, selecting strains according to the measurement result, preparing into a microbial inoculum, and placing the microbial inoculum in a container;

s2: the method comprises the following steps that a bacterium injection net is flatly laid in a goaf to be filled with waste rocks, the bacterium injection net comprises a plurality of inner pipes and side pipes on two sides, the inner pipes are arranged in parallel, two ends of each inner pipe are respectively connected with the side pipes on the two sides, a valve is arranged at the joint of each inner pipe and each side pipe, a plurality of first nozzles are distributed on each inner pipe, and a plurality of water sensors are arranged among the inner pipes;

s3: arranging a second spray head above the end head of the reversed loader, wherein the second spray head is connected with a container containing microbial inoculum through a conveying pipeline, and a pumping device is arranged on the conveying pipeline; when filling starts, the pumping device and the second spray head are started, so that the microbial inoculum is attached to the gangue passing through the transfer conveyor;

s4: after filling, detect the ponding region through the water sensor, after the water sensor detected the ponding region, open the valve of this water sensor both sides inner tube that detects the ponding region and the shower nozzle one adjacent with this water sensor, spout the ponding region with the microbial inoculum, spout the fungus and accomplish the back, close shower nozzle one, open the valve at adjacent inner tube both ends, make unnecessary microbial inoculum flow out.

As a further preferable technical scheme, the step S1 specifically comprises the steps of measuring the content of heavy metal ions in the gangue to be filled, selecting strains according to the measurement result, preparing a microbial inoculum, and placing the microbial inoculum in a container, wherein the strains are prepared by taking the copper ion content of 2.0 mg/L, the cobalt ion content of 0.5 mg/L and the nickel ion content of 0.5 mg/L as standards, the Sporosarcina koreensis UR47 strain is adopted when the exceeding multiple of the copper ions is maximum, the Sporosarcina spUR31 strain is adopted when the exceeding multiple of the cobalt ions is maximum, and the Terrabacter tomescens strain is adopted when the exceeding multiple of the nickel ions is maximum.

As a further preferable technical solution, the inner pipes in the step S2 are connected by the first nozzle, the first nozzles on the adjacent inner pipes form an area of 10m × 10m, and the water sensor is placed at the center of the area of 10m × 10 m.

As a further preferable embodiment, in the step S3, the relationship between the jet flow rate of the second nozzle and the conveying capacity of the transfer conveyor is

Wherein Q is the jet flow, k is the adhesion compensation coefficient, k is more than or equal to 1 and less than or equal to 1.5, G is the waste rock conveying capacity, r is the waste rock grain diameter, and rho is the waste rock density.

As a further preferable technical scheme, the microbial inoculum is a mixed solution formed by mixing a strain and a nutrient solution according to the volume ratio of 1 to 4.

In a further preferred embodiment, the nutrient solution is a mixed solution of urea and calcium chloride solution with equal concentration and equal proportion.

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

according to the method for curing the heavy metal in the coal gangue by using the microorganisms, the microorganism is attached before the gangue is filled, so that the heavy metal in the gangue in a goaf can be directly cured; after filling, when accumulated water exists in the goaf, the bacterium injection net can be used for supplementing the bacterium agent, so that secondary curing is realized, migration pollution of heavy metal ions is reduced, the curing effect is enhanced, and the method has the characteristics of small pollution and simplicity in treatment.

Drawings

FIG. 1 is a flow chart of the present invention;

FIG. 2 is a schematic diagram of the microbial inoculum network of the present invention;

FIG. 3 is a numbered schematic of the valve and water sensor of the present invention;

in fig. 2: 1 is an edge steel pipe, 2 is a valve, 3 is an inner steel pipe, 4 is a nozzle I, and 5 is a water sensor.

The specific implementation mode is as follows:

the invention is further described below with reference to the accompanying drawings.

Examples

Referring to FIGS. 1-3, taking a mine as an example, the density of the gangue after filling treatment is 2000kg/m³The average particle size of the waste rock is 10cm, the waste rock filling capacity is 200T/h, the waste rock is analyzed by a solid waste leaching toxicity leaching method horizontal oscillation method (HJ557-2009) and a solid waste leaching toxicity leaching method sulfuric acid-nitric acid method (HJ/T299-2007), and the copper ion content is 26.20 mg/L, the cobalt ion content is 0.84 mg/L, the nickel ion content is 4.72 mg/L, the length of a working face is 200m, and the propelling length of the working face is 1000 m.

(1) The measured copper ion is 13 times of the limit value, the cobalt ion is close to 2 times, the nickel ion is about 9.5 times, and at the moment, Sporosarcina koreensis UR47 strain is selected;

(2) culturing the strain until OD600 is 0.8, taking a mixed solution of calcium acetate and urea as a nutrient solution, wherein the concentration of the mixed solution is 1 mol/L, and mixing every 100ml of microbial inoculum with 400ml of the nutrient solution to prepare the microbial inoculum;

(3) arranging a bacterium injection network along the working face direction, wherein edge steel pipes 1 are connected to inner steel pipes 3 through valves 2, 9 rows of the valves 2 are arranged, the inner steel pipes 3 are connected through spray heads 4, 100 edge steel pipes 1 are arranged along the working face advancing direction, 20 inner steel pipes 3 are arranged along the working face direction, a first spray head on the adjacent inner steel pipes 3 forms a 10m × 10m area, a water sensor 5 is arranged at the center of the 10m × 10m area, the first steel pipe and the tail end steel pipe are not arranged, 18 sensors are arranged in each row, and each sensor monitors the 10m × 10m area;

(4) the valves are numbered, the first in the first row is A11, the second is A12, and so on; numbering the spray heads, wherein the first spray head in the first row is B11, the first spray head in the first row is B12, the first spray head in the second row is B21, and the like; numbering the sensors, wherein the first sensor in the first row is C11, the second sensor in the first row is B12, the first sensor in the second row is B21, and the like;

(5) when the goaf is filled with the waste rocks, the microbial inoculum is conveyed to a second position of a head sprayer of the transfer conveyor through a microbial transmission pipeline, so that the microbial inoculum is attached to the surface of the waste rocks, and the jet flow is high

k is 1.2, and the jet flow is calculated to be 120L/min;

(6) taking a water sensor numbered C11 as an example, when a C11 alarms, water accumulation in the area is displayed, valves A11 and A21 and spray heads B11, B12, B21 and B22 are opened, bacteria in the area are sprayed and treated, the using amount of the bacteria in the area is 1000L, after the bacteria spraying is finished, the spray heads are closed, and A12 and A22 are opened, so that redundant bacteria flow out.

Claims (3)

1. A method for solidifying heavy metal in coal gangue by using microorganisms is characterized by comprising the following steps:

s1, measuring the content of heavy metal ions in the gangue to be filled, selecting strains according to the measurement result, preparing a microbial inoculum, and placing the microbial inoculum in a container, wherein the microbial inoculum is prepared by taking the copper ion content of 2.0 mg/L, the cobalt ion content of 0.5 mg/L and the nickel ion content of 0.5 mg/L as standards, when the exceeding multiple of the copper ions is maximum, a Sporosarcina koreensis UR47 strain is adopted, when the exceeding multiple of the cobalt ions is maximum, a Sporosarcina spUR31 strain is adopted, when the exceeding multiple of the nickel ions is maximum, a Terabaactumescens strain is adopted, the microbial inoculum is a mixed solution formed by mixing the strains and a nutrient solution according to the volume ratio of 1 to 4, and the nutrient solution is an equal-proportion mixed solution of urea and calcium chloride solution with equal concentration;

s2: the method comprises the following steps that a bacterium injection net is flatly laid in a goaf to be filled with waste rocks, the bacterium injection net comprises a plurality of inner pipes and side pipes on two sides, the inner pipes are arranged in parallel, two ends of each inner pipe are respectively connected with the side pipes on the two sides, a valve is arranged at the joint of each inner pipe and each side pipe, a plurality of first nozzles are distributed on each inner pipe, and a plurality of water sensors are arranged among the inner pipes;

s3: arranging a second spray head above the end head of the reversed loader, wherein the second spray head is connected with a container containing microbial inoculum through a conveying pipeline, and a pumping device is arranged on the conveying pipeline; when filling starts, the pumping device and the second spray head are started, so that the microbial inoculum is attached to the gangue passing through the transfer conveyor;

s4: after filling, detect the ponding region through the water sensor, after the water sensor detected the ponding region, open the valve of this water sensor both sides inner tube that detects the ponding region and the shower nozzle one adjacent with this water sensor, spout the ponding region with the microbial inoculum, spout the fungus and accomplish the back, close shower nozzle one, open the valve at adjacent inner tube both ends, make unnecessary microbial inoculum flow out.

2. The method for curing coal gangue heavy metals with microorganisms as claimed in claim 1, wherein the inner pipes in the step S2 are connected through a first nozzle, the first nozzles on the adjacent inner pipes form a 10m × 10m area, and the water sensor is placed at the center of the 10m × 10m area.

3. The method for curing the coal gangue heavy metal with the microorganisms as claimed in claim 1, wherein the relationship between the jet flow rate of the second spray nozzle and the conveying capacity of the reversed loader in the step S3 is

Wherein Q is the jet flow, k is the adhesion compensation coefficient, k is more than or equal to 1 and less than or equal to 1.5, G is the waste rock conveying capacity, r is the waste rock grain diameter, and rho is the waste rock density.

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