Technological process for preparing coal spontaneous combustion prevention and control material by recycling coal slime and application of technological process

Abstract

The invention discloses a process flow for preparing a coal spontaneous combustion prevention and control material by recycling coal slime and application thereof, and the process flow comprises the following steps: extracting and filter-pressing the coal slime to obtain a coal slime cake, crushing the coal slime cake into coal slime blocks, and drying, stirring and crushing the coal slime blocks by using a paddle dryer to obtain small coal slime blocks with smaller particle size, the preparation method comprises the following steps: weighing coal slime, grinding the coal slime into small coal slime blocks, grinding the small coal slime blocks into coal slime powder of which the particle size does not exceed 50 microns, pouring the weighed coal slime powder and composite colloid into a stirrer, and stirring and mixing the coal slime powder, water and composite colloid in the stirrer according to a ratio of 100: 100: 1 to obtain the viscous coal spontaneous combustion prevention and control material with better water retention. The byproduct coal slime in power plant production has the fire prevention and extinguishing material performance, a useful fire prevention and extinguishing material is formed, and the coal slime is effectively recycled.

Description

Technical Field

[0001] The invention relates to the field of coal spontaneous combustion prevention and control, and in particular to a process flow and application of coal slime recycling and reuse to prepare coal spontaneous combustion prevention and control materials. Background Art

[0002] In a thermal power plant, the main energy source for thermal power generation comes from coal burning. In the material transportation system of the power plant, coal will be scattered during transportation. During daily cleaning, workers use water to wash the ground, racks, walls and other surfaces, causing a large amount of coal powder and environmental debris to enter the sewage treatment system of the power plant and flow into the sedimentation tank. The ground wastewater, rainwater and other sewage in the entire power plant environment will also enter the sedimentation tank of the sewage treatment system.

[0003] In the related technology, the sedimentation tank is a multi-stage treatment system. The byproducts of the power plant production, coal slime and wastewater, enter the sedimentation tank through the sewage treatment system of the power plant. After multi-stage sedimentation, there will be a large amount of coal slime in the sedimentation tank. When the power plant handles the coal slime, it usually uses an excavator to regularly dig out the deposited coal slime in the sedimentation tank, and then transports it by truck and dumps it in the coal shed. During the transportation to the coal shed, the spillage of coal slime and wastewater will cause secondary pollution. Finally, after natural air drying, it is pulled to the coal yard for stacking.

[0004] With regard to the above-mentioned related technologies, power plants can produce dozens of tons of coal slime every day. The treatment of the coal slime in the sedimentation pool requires a lot of transportation and storage costs, and it is impossible to take effective recycling measures for the by-product coal slime in the power plant production. In addition, the stacked coal slime contains more water and debris, which will also affect the coal quality and easily cause coal spontaneous combustion. Summary of the invention

[0005] In order to make the coal slime, a byproduct of power plant production, have fire-fighting material properties and effectively recycle the coal slime, the present application provides a process flow and application of recycling coal slime to prepare coal spontaneous combustion prevention and control materials.

[0006] On the one hand, the present application provides a process flow for preparing coal spontaneous combustion prevention materials by recycling coal slime, adopting the following technical scheme: The process flow of recycling coal slime to prepare coal spontaneous combustion prevention materials includes the following steps: S1; after the wastewater and coal slime in the sedimentation tank are extracted together, they flow to the filter press device, the coal slime is filtered out from the wastewater, and compressed into coal slime cakes with less water content; S2; conveying the coal slime cake to the crushing device, crushing the coal slime cake into coal slime blocks with a particle size of 5-20 mm; S3; the coal slime blocks are transported into a paddle dryer for drying, so that the moisture content of the coal slime blocks is below 5%, and then the coal slime blocks are stirred and crushed using a paddle dryer to obtain small pieces of coal slime with a particle size of no more than 5 mm; S4; conveying the small pieces of coal sludge to a dry ball mill, grinding the small pieces of coal sludge into coal sludge powder having a particle size not exceeding 50 microns; S5; convey the coal slime powder to the coal slime silo, and then convey the water-absorbing composite colloid to the composite colloid silo, convey the coal slime powder in the coal slime silo to the first belt weigh feeder, and convey the composite colloid in the composite colloid silo to the second belt weigh feeder, and then pour the weighed coal slime powder and composite colloid into the blender together, and then add water into the blender, mix and stir to obtain coal spontaneous combustion prevention material; wherein the mass ratio of the coal slime powder, water and composite colloid in the blender is 100:100:1.

[0007] Optionally, in S1, the extraction equipment includes a mixer and a submersible sewage pump.

[0008] Optionally, between S1 and S2, the wastewater from the filter press is returned to the sedimentation tank.

[0009] Optionally, in S3, the power plant's own hot steam is used to pass into the paddle dryer.

[0010] Optionally, in S3, the drying temperature is controlled at 120°C.

[0011] Optionally, in S5, two agitators are provided, and both the first belt weigh feeder and the second belt weigh feeder are connected to an electro-hydraulic three-way distributor, and the two electro-hydraulic three-way distributors work alternately, and the electro-hydraulic three-way distributors can deliver the circulating materials to the two agitators respectively.

[0012] On the other hand, the present application provides the application of the coal spontaneous combustion prevention material prepared by the process flow in suppressing the spontaneous combustion of coal piles, adopting the following technical scheme: The application of the coal spontaneous combustion prevention material prepared by the process flow in suppressing the spontaneous combustion of coal piles includes the following steps: spraying the viscous coal spontaneous combustion prevention material with good water retention after stirring onto the coal pile to cover the surface of the coal pile and suppress the spontaneous combustion of the coal pile.

[0013] Optionally, the coal spontaneous combustion prevention material is transported to the spray gun through a grouting pump and then sprayed onto the surface of the coal pile through the spray gun.

[0014] In summary, the present application includes at least one of the following beneficial technical effects: First, the coal slime is extracted and filtered to form a coal slime cake, and then the coal slime cake is broken into coal slime blocks, and then the coal slime blocks are dried and stirred and broken by a paddle dryer to obtain small pieces of coal slime with a smaller particle size, and then the small pieces of coal slime are ground into coal slime powder with a particle size not exceeding 50 microns, and then the weighed coal slime powder and composite colloid are poured into a stirrer, and the coal slime powder, water, and composite colloid in the stirrer are stirred and mixed at a ratio of 100:100:1 to obtain a viscous coal spontaneous combustion prevention material with good water retention. Through the technical solution of the present application, the byproduct coal slime in the production of power plants has the performance of fire-proof extinguishing materials, forming a useful fire-proof extinguishing material, and effectively recycling the coal slime; Two agitators are provided, and the first belt weighing feeder and the second belt weighing feeder are both connected with an electro-hydraulic three-way distributor, and the two electro-hydraulic three-way distributors work alternately. The electro-hydraulic three-way distributor can deliver the circulating materials to the two agitators respectively, so that the two agitators can work simultaneously, thereby improving the mixing processing efficiency and output; When the paddle dryer is used to dry the coal slime blocks, the power plant's own hot steam is used to pass into the paddle dryer, which can save the production cost of the paddle dryer's hot steam and improve the recycling efficiency of energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the process flow and application of the present application of recycling coal slime to prepare coal spontaneous combustion prevention material.

[0016] Figure 2 It is a schematic diagram of the process of coal slime flowing from the crushing device to the agitator.

[0017] Explanation of the reference numerals in the accompanying drawings: 1. Sedimentation tank; 21. Diaphragm filter press; 22. High-efficiency cyclone purifier; 3. Crushing device; 4. Paddle dryer; 5. Dry ball mill; 6. Coal sludge silo; 7. Composite colloid silo; 8. First belt weigh feeder; 9. Second belt weigh feeder; 10. Agitator; 11. Coal spontaneous combustion prevention and control materials; 12. Coal pile; 13. Agitator; 14. Submersible sewage pump; 15. Electro-hydraulic three-way distributor; 16. Grouting pump; 17. Spray gun; 18. Scraper conveyor; 19. Bucket elevator. DETAILED DESCRIPTION

[0018] The present application is further described in detail below in conjunction with all the accompanying drawings.

[0019] On the one hand, the embodiments of the present application disclose a process flow for recycling coal slime to prepare coal spontaneous combustion prevention and control materials.

[0020] Example 1

[0021] Reference Figure 1 and Figure 2The process flow of recycling coal slime to prepare coal spontaneous combustion prevention materials includes the following steps: S1; the wastewater and coal slime in the sedimentation tank 1 are extracted together using an extraction device, the extraction device includes a mixer 13 and a submersible sewage pump 14, the mixer 13 stirs and suspends the deposited coal slime in the sedimentation tank, and then the submersible sewage pump 14 is used to extract the wastewater and coal slime. The extraction method omits the step of regularly cleaning the coal slime by the excavator, thereby saving labor costs and the use of the excavator; The wastewater and coal slime are then transferred to a filter press device, which may be a membrane filter press 21 or a high-efficiency cyclone purifier 22. The membrane filter press 21 or the high-efficiency cyclone purifier 22 filters the coal slime out of the wastewater and compresses the coal slime into a coal slime cake with less water content. The wastewater is then returned to the sedimentation tank 1 to reduce pollution and avoid excessive liquid accumulation at the filter press device. S2; the coal slime cake is transported to the crushing device 3 through the scraper conveyor 18, and the crushing device 3 may use a roller crusher to crush the coal slime cake into coal slime blocks with a particle size of 5-20 mm; S3; the coal slime blocks are transported into the paddle dryer 4, the coal slime blocks containing water are dried to make the moisture content of the coal slime blocks below 5%, and then the paddle dryer 4 is used to stir and crush the coal slime blocks to obtain small pieces of coal slime with a particle size of no more than 5 mm; A large amount of hot steam is generated when the power plant generates electricity. When the paddle dryer 4 dries the coal slime, the drying temperature is controlled at 120°C. Using the power plant's own hot steam to pass into the paddle dryer 4 can save the production cost of the hot steam of the paddle dryer 4 and improve the recycling efficiency of energy. S4; conveying the small pieces of coal slime to the dry ball mill 5, grinding the small pieces of coal slime into coal slime powder having a particle size not exceeding 50 microns; S5; convey the coal slime powder to the coal slime silo 6 through a bucket elevator 19, and then convey the water-absorbing composite colloid to the composite colloid silo 7 through another bucket elevator 19. The composite colloid is formed by a base material and a trace amount of coagulant. The base material can be silica gel, and the coagulant is ammonium bicarbonate, sodium bicarbonate and aluminate. The composite colloid has good high temperature resistance, certain leak-proofing and chemical resistance, will not vaporize rapidly at high temperature, and has good heat absorption and cooling performance. The coal slime powder in the coal slime silo 6 is conveyed to the first belt weighing feeder 8, and the composite colloid silo 7 conveys the composite colloid to the second belt weighing feeder 9. The first belt weighing feeder 8 and the second belt weighing feeder 9 can realize accurate weighing of the material and convey the material; Pour the weighed coal slime powder and composite colloid into the blender 10 together, and then add water into the blender 10 (water can be added through the water inlet valve of the blender 10). The mass ratio of the coal slime powder, water and composite colloid in the blender 10 is 100:100:1. After mixing and stirring, a viscous coal spontaneous combustion prevention material 11 with good water retention is obtained.

[0022] Two agitators 10 are provided, and the coal slurry powder and the composite colloid in each agitator 10 are kept in the same ratio. The first belt weighing feeder 8 and the second belt weighing feeder 9 are both connected to an electro-hydraulic three-way distributor 15, which is used for material reversal and diversion, and has the function of controlling the cutting off or simultaneous circulation of materials. The two electro-hydraulic three-way distributors 15 work alternately, and the electro-hydraulic three-way distributors 15 can realize the conveying of the circulating materials to the two agitators 10 respectively, so that the two agitators 10 can work simultaneously, thereby improving the mixing processing efficiency and output.

[0023] Through the process flow of the present application, the coal slime, which is a byproduct of power plant production, has the properties of a fire-proof and extinguishing material, forming a useful fire-proof and extinguishing material, and effectively recycling the coal slime.

[0024] The process flow of preparing coal spontaneous combustion prevention material by recycling coal slime in the embodiment of the present application and the implementation principle of its application are as follows: first, the coal slime is extracted and filtered to obtain coal slime cake, and then the coal slime cake is crushed into coal slime blocks, and then the coal slime blocks are dried and stirred and crushed by a paddle dryer 4 to obtain small pieces of coal slime with smaller particle size, and then the small pieces of coal slime are ground into coal slime powder with a particle size not exceeding 50 microns, and then the weighed coal slime powder and composite colloid are poured into an agitator 10, and the coal slime powder, water, and composite colloid in the agitator 10 are stirred and mixed in a ratio of 100:100:1 to obtain a viscous coal spontaneous combustion prevention material 11 with good water retention, and then the coal spontaneous combustion prevention material 11 is sprayed onto a coal pile 12 to cover the surface of the coal pile 12 and prevent the spontaneous combustion of the coal pile 12. Through the technical solution of the present application, the coal slime, a by-product in the production of a power plant, has the performance of a fire-proof material, forming a useful fire-proof material, and realizing effective recycling of the coal slime.

[0025] On the other hand, the application example of the present application discloses the application of the coal spontaneous combustion prevention material prepared by the process flow in suppressing the spontaneous combustion of coal piles.

[0026] Example 2 Reference Figure 1 and Figure 2The application of the coal spontaneous combustion prevention material prepared by the process flow in suppressing the spontaneous combustion of coal piles includes the following steps: the viscous coal spontaneous combustion prevention material 11 with good water retention obtained after stirring is transported to the spray gun 17 through the grouting pump 16, and then sprayed onto the surface of the coal pile 12 through the spray gun 17. The coal spontaneous combustion prevention material 11 will absorb the moisture of the coal pile 12 and cover the surface of the coal pile 12. After absorbing the moisture, the evaporation rate is extremely slow, thereby suppressing the spontaneous combustion of the coal pile 12.

[0027] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. The process flow of recycling coal slime to prepare coal spontaneous combustion prevention materials is characterized by: The following steps are involved: S1； After the wastewater and coal slime are extracted from the sedimentation tank (1), the wastewater is transferred to a filter press device to filter out the coal slime from the wastewater and compress it into a coal slime cake with a low water content; S2; conveying the coal sludge cake to the crushing device (3), crushing the coal sludge cake into coal sludge blocks with a particle size of 5-20 mm; S3; conveying the coal slime block into the paddle dryer (4) for drying, so that the moisture content of the coal slime block is below 5%, and then using the paddle dryer (4) to stir and crush the coal slime block to obtain small pieces of coal slime with a particle size not exceeding 5 mm; S4; conveying the small pieces of coal sludge to a dry ball mill (5), grinding the small pieces of coal sludge into coal sludge powder having a particle size not exceeding 50 microns; S5: conveying the coal slurry powder to the coal slurry silo (6), conveying the water-absorbing composite colloid to the composite colloid silo (7), conveying the coal slurry powder in the coal slurry silo (6) to the first belt weighing feeder (8), conveying the composite colloid in the composite colloid silo (7) to the second belt weighing feeder (9), and then pouring the weighed coal slurry powder and the composite colloid into the agitator (10), adding water to the agitator (10), mixing and stirring to obtain the coal spontaneous combustion prevention material (11); wherein the mass ratio of the coal slurry powder, water and composite colloid in the agitator (10) is 100:100:

1.

2. The process flow of preparing coal spontaneous combustion prevention material by recycling coal slime according to claim 1 is characterized in that: In S1, the extraction equipment includes a mixer (13) and a submersible sewage pump (14).

3. The process flow of preparing coal spontaneous combustion prevention material by recycling coal slime according to claim 1 is characterized in that: Between S1 and S2, the wastewater from the filter press is returned to the sedimentation tank (1).

4. The process flow of preparing coal spontaneous combustion prevention material by recycling coal slime according to claim 1 is characterized in that: In S3, the power plant's own hot steam is used to pass into the paddle dryer (4).

5. The process flow of preparing coal spontaneous combustion prevention material by recycling coal slime according to claim 1 is characterized in that: In S3, the drying temperature is controlled at 120°C.

6. The process flow of preparing coal spontaneous combustion prevention material by recycling coal slime according to claim 1 is characterized by: In S5, two agitators (10) are provided, and the first belt weighing feeder (8) and the second belt weighing feeder (9) are both connected to an electro-hydraulic three-way distributor (15). The two electro-hydraulic three-way distributors (15) work alternately, and the electro-hydraulic three-way distributors (15) can respectively transport the circulating materials to the two agitators (10).

7. The application of the coal spontaneous combustion prevention material prepared by the process of claim 1 in suppressing spontaneous combustion of coal piles is characterized by: The viscous coal spontaneous combustion prevention material (11) with good water retention obtained after stirring is sprayed onto the coal pile (12) to cover the surface of the coal pile (12) and inhibit the spontaneous combustion of the coal pile.

8. The use of the coal spontaneous combustion prevention material according to claim 7 in suppressing spontaneous combustion of coal piles, characterized in that: The coal spontaneous combustion prevention material (11) is transported to the spray gun (17) through the grouting pump (16), and then sprayed onto the surface of the coal pile (12) through the spray gun (17).

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