CN103482746A - Method for treating sewage by using coal mine wastes - Google Patents

Abstract

The invention relates to the technical field of waste water treatment, using coal gangue, waste acid, waste iron chips and other industrial waste produced in the production process of coal mining enterprises as raw materials, and preparing a new coagulant under the conditions of alkali dissolution, acid dissolution and oxidation; Design and transform coal mine subsidence basins into sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds, and treat production wastewater and domestic sewage with coagulation, sedimentation, and aerobic oxidation. It solves the problems of land occupation for coal gangue storage and waste acid treatment; reduces the operating cost of sewage treatment plants; at the same time realizes the discharge of sewage after treatment, or meets the water quality requirements of reused water for reuse in coal mine production and life. The invention has convenient operation and low investment.

Description

A method of using coal mine waste to treat sewage

technical field

The invention relates to the technical field of wastewater treatment, in particular to a coal mine wastewater treatment method and a system thereof.

Background technique

Coal mining enterprises produce a large amount of coal gangue and other wastes during the mining process, and stacking these coal gangues requires a certain amount of land; miner's lamp houses will produce a certain amount of waste acid; machinery factories will produce a certain amount of iron filings and other wastes. At the same time, in order to ensure the safety of production, coal mines need to discharge a large amount of underground water. The underground water comes from the coal mining face, the tunneling head and the old goaf. It contains a large amount of coal dust, rock particles and a certain amount of bacteria, so it is not treated. Emissions can cause pollution of surface water bodies.

Therefore, how to rationally and economically utilize these wastes such as coal gangue and process and utilize underground water has become a difficult problem for major coal mining enterprises.

Contents of the invention

The technical problem to be solved by the present invention is: the present invention proposes a new coagulant prepared by using industrial wastes such as coal gangue, waste acid, and scrap iron scraps produced in the production process of coal mine enterprises as raw materials. The production wastewater and domestic sewage of coal mines are treated, which solves the problems of coal gangue storage and waste acid treatment; reduces the operating cost of sewage treatment plants; at the same time, uses coal gangue as filling material to transform and design subsidence basins into Oxidation ponds are used to treat domestic sewage and underground production sewage. Combine the treatment and utilization of coal gangue with the resource utilization of sewage, and take the road of treating waste with waste. At the same time, it can meet the standard discharge after sewage treatment, or meet the water quality requirements of reused water for reuse in the production and life of coal mines.

The technical solution adopted by the present invention to solve its technical problems is: the processing method of the present invention is implemented according to the following steps:

(1), first pass the production wastewater and domestic sewage into the coagulation reaction tank;

(2), then add coagulant in the wastewater coagulation reaction tank, stir and mix for 30 minutes;

(3) The stirred and mixed wastewater is introduced into the sedimentation pond, and the hydraulic retention time is two days;

(4) The effluent from the sedimentation pond is introduced into the oxidation pond, the culture pond, and the lotus root pond in sequence, and the effluent is discharged or reused.

The production process of the coagulant described in step (1) is as follows:

a. Grinding and screening coal gangue;

b. Immerse the sieved coal gangue in the NaOH solution of 2.0mol/L, heat at 80 degrees, stir for 8 hours, and filter;

c. Add waste acid with a concentration of 30% to the gangue filtrate, keep the pH value at 2.0, stir, and react for 2 hours at a temperature of 80 degrees;

d. Mix the iron filings produced by the machinery factory with the coal gangue filter residue, immerse in the waste acid with a concentration of 30%, stir, and react for 1 hour at a temperature of 60 degrees.

e. Filter the reactant in step d, add hydrogen peroxide to the filtrate, and stir and react at a temperature of 60 degrees for 30 minutes.

f. Add the reactant of step c to the reactant of step e, stir and react for 30 minutes at a temperature of 60 degrees, and cool to obtain a coagulant;

The sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds described in steps (3) and (4) are transformed from subsidence basins of coal mines. The modification steps are as follows:

① Determine the location and area of sedimentation ponds, oxidation ponds, etc. according to the size and design of the treated water;

②Peel off the surface soil of sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds, with a thickness of 1.5 meters, pile up the stripped soil around the ponds, and mix it with coal gangue to form the cofferdam of the ponds;

③Adjacent sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds are provided with connecting channels for water in and out;

④ Adjacent sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds are connected in series through connecting channels.

The beneficial effect of the present invention is to use industrial wastes such as coal gangue, waste acid, and scrap iron pins produced in the production process of coal mine enterprises as raw materials to prepare a new coagulant, and use the coagulant to treat the production wastewater and domestic sewage of coal mines. The treatment solved the problems of coal gangue storage and waste acid treatment; at the same time, coal gangue was used as filling material to transform and design the subsidence basin into sedimentation ponds and oxidation ponds to treat domestic sewage and underground production sewage. Combining the treatment and utilization of coal gangue with the resource utilization of sewage, we will take the road of treating waste with waste.

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Fig. 1 is a plan view of a specific embodiment of the present invention.

In the figure: 1. Water inlet, 2. Sedimentation pond, 3. Cofferdam, 4. Oxidation pond, 5. Connecting canal, 6. Breeding pond, 7. Lotus root pond, 8. Water outlet.

Detailed ways

Now in conjunction with accompanying drawing 1 the present invention is described in further detail. These drawings are all simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, so they only show the configurations related to the present invention.

(1) First, the production wastewater and domestic sewage are passed into the coagulation reaction tank, and the size of the coagulation reaction tank is determined according to the water volume design of the production wastewater and domestic sewage;

(2), then add coagulant in the wastewater coagulation reaction tank, stir and mix for 30 minutes;

(3) The stirred and mixed wastewater is introduced into the sedimentation pond 2 through the water inlet 1, and the hydraulic retention time is two days;

(4) The effluent from the sedimentation pond 2 is sequentially introduced into the oxidation pond 4 , the culture pond 6 , and the lotus root pond 7 , and the effluent is discharged or reused through the water outlet 8 .

The production process of the coagulant described in step (1) is as follows:

a. Grinding and screening of coal gangue;

b. Immerse the sieved coal gangue in 2.0mol/L NaOH solution, heat at 80 degrees, stir for 8 hours; filter;

c. Add waste acid with a concentration of 30% to the gangue filtrate, keep the pH value at 2.0, stir, and react for 2 hours at a temperature of 80 degrees;

d. Mix the iron filings produced by the machinery factory with the coal gangue filter residue, then immerse in the waste acid with a concentration of 30%, stir, and react for 1 hour at a temperature of 60 degrees.

e. Filter the reactant in step d, add hydrogen peroxide to the filtrate, and stir and react at a temperature of 60 degrees for 30 minutes.

f. Add the reactant of step c to the reactant of step e, stir and react for 30 minutes at a temperature of 60 degrees, and cool to obtain a coagulant;

The sedimentation pond 2, the oxidation pond 4, the breeding pond 6, and the lotus root pond 7 described in steps (3) and (4) are transformed from subsidence basins of coal mines. The transformation steps are as follows:

① Determine the location and area of sedimentation pond 2, oxidation pond 4, breeding pond 6, and lotus root pond 7 according to the size and design of the treated water;

2. Stripping the topsoil of sedimentation pond 2, oxidation pond 4, culture pond 6, lotus root pond 7, the thickness of stripping is 1.5 meters, and the stripped soil is piled up around the pond, and mixed with coal gangue to build a cofferdam;

③ Adjacent sedimentation pond 2, oxidation pond 4, breeding pond 6, and lotus root pond 7 are provided with connecting channels 5 for inflow and outflow of water;

④ Adjacent sedimentation pond 2, oxidation pond 4, breeding pond 6, lotus root pond 7 run in series through the connecting channel 5.

Inspired by the above-mentioned ideal embodiment according to the present invention, through the above-mentioned description content, relevant workers can make various changes and modifications within the scope of not departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, but must be determined according to the scope of the claims.

Claims (3)

1. A method for utilizing coal mine waste to treat sewage has the following steps: (1), first pass the production wastewater and domestic sewage into the coagulation reaction tank; (2), then add coagulant in the coagulation reaction tank, stir and mix for 30min; (3) Introduce the stirred and mixed wastewater into the sedimentation pond, and the hydraulic retention time is two days; (4) The effluent from the sedimentation pond is introduced into the oxidation pond, the culture pond, and the lotus root pond in sequence, and the effluent is discharged or reused. the 2. the making process of coagulant as claimed in claim 1 is as follows: a. Grinding and screening coal gangue; b. Immerse the sieved coal gangue in 2.0mol/L NaOH solution, heat at 80 degrees, stir for 8 hours, and filter; c. Add waste acid with a concentration of 30% to the gangue filtrate, keep the pH value at 2.0, stir, and react for 2 hours at a temperature of 80 degrees; d. Mix the iron filings produced by the machinery factory with the coal gangue filter residue, then immerse in the waste acid with a concentration of 30%, stir, and react for 1 hour at a temperature of 60 degrees. the e. Filter the reactant in step d, add hydrogen peroxide to the filtrate, and stir and react at a temperature of 60 degrees for 30 minutes. the f. Add the reactant of step c to the reactant of step e, stir and react for 30 minutes at a temperature of 60 degrees, and cool to obtain a coagulant. 3. The sedimentation pond, oxidation pond, breeding pond, and lotus root pond as claimed in claim 1 are transformed from the subsidence basin of the coal mine, and the transformation steps are as follows:  ① Determine the location and area of sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds according to the size and design of the treated water; ② Strip the surface soil of sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds, with a thickness of 1.5 meters, accumulate the stripped soil around the ponds, and mix them with coal gangue to build the cofferdams of the ponds; ③Adjacent sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds are provided with connecting channels for inflow and outflow of water;  ④ Adjacent sedimentation ponds, oxidation ponds, breeding ponds, and lotus root ponds are connected in series through connecting channels. the

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