A coal slurry treatment system and method for a coal conveying system of a thermal power plant

Abstract

The application discloses a kind of for coal conveying system of thermal power plant sedimentation tank coal slime processing system and method, it is related to the technical field of sedimentation tank maintenance processing of coal conveying system of thermal power plant.The sedimentation tank coal slime processing system, including multistage sedimentation filter tank, sewage pump, single-beam grab crane, variable angle hopper, belt conveyor.Multistage sedimentation filter tank is set in the vicinity of coal storage yard coal unloading belt, and the function of gradually sedimentation filtration coal conveying system containing coal wastewater is played, sewage pump is used to discharge the sewage of sedimentation tank outside system;Single-beam grab crane is used to grab and transport coal slime in the sedimentation tank to coal conveying belt;Variable angle hopper is used to unload coal slime on belt conveyor;Belt conveyor is the coal conveying system coal storage yard coal unloading equipment.The application has simple structure, is convenient and practical, can effectively solve the environmental pollution problem in the process of coal slime cleaning in coal conveying system sewage discharge system, and also can improve personnel work efficiency, reduce production cost.

Description

Technical Field

[0001] This invention belongs to the field of thermal power generation technology, specifically relating to a coal slime treatment system and method for a sedimentation tank in a coal conveying system of a thermal power plant. Background Technology

[0002] The coal-containing wastewater collection, discharge, and treatment system is a crucial component of the coal conveying system in thermal power plants. Early thermal power plants often had drying ponds in their wastewater discharge systems. After sedimentation in the sedimentation ponds, the coal-containing wastewater was transported to the drying ponds by grab buckets. It was left to dry for several days until the coal slime was slightly dried, then transported to the coal storage yard by loaders and enclosed transport vehicles. Power plants without drying ponds directly transported the coal slime to open areas at both ends of the coal storage yard using enclosed transport vehicles, where it was left to dry for several days before being pushed to the coal yard by coal pushers. Both of these methods of coal slime treatment are not only expensive but also severely pollute the roads and sites along the route.

[0003] In recent years, with increasingly stringent environmental protection requirements, the cleaning of coal sludge in sedimentation tanks has seriously affected the environmental protection indicators of Dezhou Power Plant. There is an urgent need to design, plan, and construct a sedimentation tank coal sludge discharge system that is environmentally friendly, easy to clean, simple in structure, and convenient to maintain. Summary of the Invention

[0004] The purpose of this invention is to provide a coal slime treatment system and method for sedimentation tanks in coal conveying systems of thermal power plants, based on the current situation. This invention makes full use of the advantageous condition that the coal storage yard is equipped with belt conveyors. Its structure is simple, convenient and practical. It not only effectively reduces the production cost of coal slime treatment, but more importantly, it can achieve zero pollution on site and meet environmental protection requirements.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A coal slime treatment system for sedimentation tanks in coal conveying systems of thermal power plants includes multi-stage sedimentation and filtration tanks, sewage pumps, single-beam grab cranes, variable-angle funnels, and belt conveyors; The multi-stage sedimentation and filtration tank is located near the belt conveyor in the coal storage yard and is used to sediment and filter coal-containing wastewater from the coal conveying system in stages. The sewage pump is installed in the final stage sedimentation and filtration tank of the multi-stage sedimentation and filtration tank, and is used to discharge the sewage treated by the multi-stage sedimentation and filtration tank out of the tank. The single-beam grab crane is located above the multi-stage sedimentation and filtration tank and is used to grab coal slurry from the multi-stage sedimentation and filtration tank and drop the coal slurry into the variable-angle funnel. The variable tilt angle funnel is installed directly above the belt conveyor to separate wastewater from coal slurry and discharge it into a multi-stage sedimentation and filtration tank, while simultaneously unloading the coal slurry onto the coal flow of the belt conveyor. The belt conveyor is a conveyor belt used for coal blending in the coal storage yard, and it operates in both directions.

[0006] A further improvement of the present invention is that the multi-stage sedimentation filtration tank consists of 6 filtration tanks, and the distance between the tank and the belt conveyor does not exceed 10,000 mm. The tank is constructed with cement, and the size is determined according to the actual site conditions. Each filtration tank is not less than 6,000 mm × 4,000 mm × 2,000 mm in length × width × depth. The adjacent sedimentation tanks in the multi-stage sedimentation filtration tank are connected by a 500mm wide gap, which is 500mm below the set water level, and the adjacent gaps are staggered. The first stage of the multi-stage sedimentation and filtration tank is equipped with an inlet pipe, through which coal-containing wastewater from the coal conveying system flows into the filtration tank.

[0007] A further improvement of the present invention is that the inlet pipe of the first-stage filter tank is located 500mm above the set water level plane of the filter tank.

[0008] A further improvement of the present invention is that a drain pipe is provided in the final stage of the multi-stage sedimentation and filtration tank, and the wastewater after multi-stage sedimentation and filtration is discharged from the system through the drain pipe. The final stage of the multi-stage sedimentation filtration system is equipped with a water level sensor, which activates when the water level is at the highest set position and stops when it is at the lowest set position.

[0009] A further improvement of the present invention is that the sewage pump is a 3PNL sewage pump; The inlet pipe of the sewage pump is the outlet pipe of the final stage sedimentation and filtration tank, located 500mm below the normal water level of the sedimentation tank. The sewage pump is started and stopped by a water level sensor that collects the sewage water level in the filter tank. When the sewage water level reaches the set height, the water level sensor triggers the controller to start and stop the sewage pump.

[0010] A further improvement of the present invention is that the single-beam grab crane is located above the multi-stage sedimentation and filtration tank, supported by columns, and the track length allows the single-beam grab crane to move directly above the belt conveyor. The crane's lifting capacity is preferably 0.75T.

[0011] A further improvement of the present invention is that the distance between the variable tilt angle funnel and the lowest point of the concave surface of the coal conveyor belt is 400mm, and the funnel is composed of a maintenance platform. The variable tilt angle funnel is made of 12mm thick Q235B steel plate, with an open hopper design and inner and outer double-layer vertical plates. The outer vertical plate has dimensions of 2000mm × 15000mm × 250mm (length × width × height), and a discharge port is set at the front end of the outer vertical plate. The width of the discharge port depends on the site conditions, and the open size should preferably be 300mm × 300mm. The inner vertical plate has dimensions of 18000mm × 13000mm × 300mm (length × width × height), with a tapered front end and a discharge port insert plate at the tapered end. The insert plate is closed when the grab bucket is unloading material and is opened after the wastewater in the coal slime has drained. The inner vertical plate has a vertical slit of 200mm × 10mm every 50mm to filter the wastewater in the coal in the funnel into the space between the inner and outer vertical plates.

[0012] A further improvement of the present invention is that the front end of the inner and outer vertical plates of the variable tilt angle funnel is provided with a φ120mm drain outlet, and a φ218 drain pipe is connected below the drain outlet to discharge the sewage overflowing from the inner vertical plate of the funnel into the sedimentation tank. In the variable tilt angle funnel, a coal flow diversion device is provided at the discharge port in the direction of the belt conveyor, and a coal flow merging device is provided at the discharge port in the direction of the belt conveyor. The coal flow diversion device is used to spread the coal flow on the belt conveyor flat, and the coal flow merging device is used to merge the coal slurry falling from the discharge port with the coal flow on the belt conveyor towards the middle.

[0013] A further improvement of the present invention is that the variable tilt angle funnel is fixed on the maintenance platform by a hinge shaft, and the hinge seat is located slightly in front of the center of the longitudinal axis of the funnel. The variable tilt angle funnel is equipped with a manual lifting device at its rear end. The lifting device consists of a lead screw, a lead screw nut, a handwheel, and a bearing. The lead screw nut is fixed to the rear side of the variable tilt angle funnel by a clamp. The rotating end of the lead screw is interference-fitted with a bearing, and the bearing seat is fixed on the maintenance platform. After the sewage in the coal slurry is drained through the drain outlet, the lead screw handwheel is rotated according to the consistency of the coal slurry to raise the rear end of the funnel, so that the funnel forms a forward tilt angle. The variable tilt angle funnel is equipped with two coal slime cleaning tools; The maintenance platform spans the belt conveyor and is set around the variable trough angle funnel. The platform is welded with #12 channel steel and has personnel passages paved with metal mesh panels, stairs, and 1200mm guardrails. The maintenance platform has a limit bar fixed at the front end of the variable tilt funnel to limit the angle of the funnel tilting forward to not exceed 30°.

[0014] A method for treating coal sludge in a sedimentation tank of a coal conveying system in a thermal power plant, the method being based on a coal sludge treatment system for a sedimentation tank of a coal conveying system in a thermal power plant, comprising: Coal-containing wastewater from the coal conveying system flows into a multi-stage sedimentation and filtration tank through the inlet pipe of the sedimentation tank. After natural sedimentation and filtration at each stage, the coal sludge gradually decreases while the wastewater gradually increases. When the wastewater level in the sixth-stage sedimentation tank reaches the set position, the wastewater is discharged from the tank by a wastewater pump. When the sedimentation tank needs cleaning, the grab crane is started to grab the coal sludge from the sedimentation tank. The crane runs along the track to directly above the variable angle funnel above the belt conveyor. The coal sludge and sewage fall into the variable angle funnel together, and the sewage is discharged into the sedimentation tank. After the sewage is discharged, the variable angle funnel is tilted forward. The coal sludge in the variable angle funnel falls onto the coal flow on the belt conveyor under its own weight and the action of auxiliary tools, bringing the coal flow from both sides towards the middle, covering the coal sludge, and then unloading it into the coal storage yard along the belt. After the coal sludge is unloaded, the variable angle funnel is returned to a horizontal state.

[0015] Compared with the prior art, the present invention has at least the following beneficial technical effects: This invention provides a closed-loop operation for the entire coal slime transfer and disposal process. The coal slime is directly transferred via grab bucket to a variable-angle funnel, and then conveyed to the coal storage yard by a belt conveyor. The entire process effectively suppresses dust, prevents coal slime spillage along the way, and avoids road pollution, meeting on-site environmental protection standards. This invention adopts a mechanized integrated operation mode, replacing traditional transport vehicles and a large amount of manual labor for coal slime cleaning, significantly reducing vehicle usage costs and labor expenses, and lowering the overall operating costs of coal slime cleaning. The invention has a simple overall structure, with a well-organized layout of components, making equipment inspection and maintenance convenient. It is suitable for the on-site working conditions of coal conveying systems in thermal power plants and has good practicality and promotional value. Multi-stage sedimentation and filtration tanks achieve step-by-step solid-liquid separation of coal-containing wastewater, and the treated wastewater can be discharged in an orderly manner. The variable-angle funnel performs secondary decontamination of the coal slime, and the separated wastewater is returned to the sedimentation and filtration tank for recycling, improving water resource utilization. After treatment, the coal slime is directly mixed back into the coal flow on the conveyor belt and transported to the coal storage yard, realizing coal slime recycling and reducing coal resource loss.

[0016] In summary, this invention relies on the existing belt conveyor to deploy the entire system. The equipment layout fits the original facilities, the operation process is smoothly connected, and it can stably adapt to the normal operation requirements of the coal conveying system. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1This is a top view of a coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant, according to the present invention. Figure 2 This is a schematic diagram showing the relationship between the variable tilt angle funnel and the belt conveyor. Figure 3 Front view of the variable tilt angle funnel; Figure 4 A top view of a funnel with a variable tilt angle; Figure 5 This is a front view of the coal flow merging device; Figure 6 This is a top view of the coal flow merging device; Figure 7 This is a front view of the coal flow diversion device; Figure 8 This is a top view of the coal flow diversion device.

[0019] Explanation of reference numerals in the attached figures: 1. Multi-stage sedimentation and filtration tank; 2. Sewage pump; 3. Sedimentation tank inlet pipe; 4. Sedimentation tank outlet pipe; 5. Single-girder grab crane; 6. Track; 7. Belt conveyor; 8. Variable angle funnel; 9. Maintenance platform; 81. Outer vertical plate of the funnel; 82. Inner vertical plate of the funnel; 83. Material discharge port of the funnel; 831. Discharge port diversion plate; 832. Discharge port diversion connecting plate; 84. Drain pipe of the funnel; 85. Funnel hinge seat; 86. Funnel screw; 87. Funnel screw handwheel; 88. Limiting crossbar; 89. Discharge port insert plate; 90. Coal flow diversion device; 901. Diversion device handwheel; 902. Diversion device screw; 903. Diversion device diversion plate; 91. Coal flow merging device. Detailed Implementation

[0020] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0021] In the description of this invention, it should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0022] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0026] Example 1 like Figure 1 As shown, the present invention provides a coal slime treatment system for sedimentation tanks in coal conveying systems of thermal power plants, including a multi-stage sedimentation and filtration tank 1, a sewage pump 2, a single-beam grab crane 5, a variable-angle funnel 8, and a belt conveyor 7. The multi-stage sedimentation and filtration tank 1 is located near the belt conveyor 7 in the coal storage yard and is used for step-by-step sedimentation and filtration of coal-containing wastewater from the coal conveying system. The sewage pump 2 is installed in the final sedimentation and filtration tank of the multi-stage sedimentation and filtration tank 1 and is used to discharge the sewage treated by the multi-stage sedimentation and filtration tank 1 out of the tank. The single-beam grab crane 5 is located above the multi-stage sedimentation and filtration tank 1 and is used to grab coal slurry in the multi-stage sedimentation and filtration tank 1 and drop the coal slurry into the variable tilt angle funnel 8. The variable tilt angle funnel 8 is installed directly above the belt conveyor 7 to separate wastewater from coal slime and discharge it into the multi-stage sedimentation and filtration tank 1, while simultaneously unloading the coal slime onto the coal flow of the belt conveyor 7. The belt conveyor 7 is a conveyor belt for coal blending in the coal storage yard, and it operates in both directions.

[0027] In this embodiment, the multi-stage sedimentation filtration tank 1 consists of 6 filtration tanks, and the distance between the tank and the belt conveyor 7 does not exceed 10,000 mm. It is constructed with cement masonry, and the size is determined according to the actual site conditions. Each filtration tank is not less than 6,000 mm × 4,000 mm × 2,000 mm in length × width × depth. The multi-stage sedimentation filtration tank 1 consists of 6 filtration tanks. Wastewater from the coal conveying system flows into the tank through the sedimentation tank inlet pipe 3. After sedimentation and filtration at each stage, the water is pumped out by the wastewater pump 2 installed in the sixth-stage filtration tank to the coal-containing wastewater pipeline.

[0028] The adjacent sedimentation tanks in the multi-stage sedimentation and filtration tank 1 are connected by a 500mm wide gap, which is 500mm below the set water level. The adjacent gaps are staggered to reduce the water flow speed and achieve the function of gradual natural sedimentation and filtration. An inlet pipe is installed in the first stage of the multi-stage sedimentation and filtration tank 1, through which coal-containing wastewater from the coal conveying system flows into the filtration tank.

[0029] In this embodiment, the inlet pipe of the first-stage filter tank is located 500mm above the set water level of the filter tank to facilitate the normal flow of coal-containing wastewater into the tank without being blocked by the settled coal sludge.

[0030] In this embodiment, a sedimentation tank drain pipe 4 is installed in the final sedimentation tank of the multi-stage sedimentation and filtration tank 1, and the sewage after multi-stage sedimentation and filtration is discharged from the system through the sedimentation tank drain pipe 4. The final stage sedimentation filter tank of the multi-stage sedimentation filter tank 1 is equipped with a water level sensor, which is activated when the water level is at the highest set position and stopped when the water level is at the lowest set position.

[0031] In this embodiment, the sewage pump 2 is a 3PNL sewage pump; The inlet pipe of the sewage pump 2 is the outlet pipe of the final stage sedimentation and filtration tank, located 500mm below the normal water level of the sedimentation tank. The sewage pump 2 is started and stopped by a water level sensor that collects the sewage water level in the filter tank. When the sewage water level reaches the set height, the water level sensor triggers the controller to start and stop the sewage pump 2.

[0032] In this embodiment, the single-beam grab crane 5 is located above the multi-stage sedimentation and filtration tank 1 and is supported by columns. The length of the track 6 allows the single-beam grab crane 5 to move directly above the belt conveyor 7. The crane's lifting capacity is preferably 0.75T.

[0033] In this embodiment, the distance between the variable tilt angle funnel 8 and the lowest point of the concave surface of the coal conveyor belt is 400mm, and it consists of a funnel and a maintenance platform 9; like Figures 3 to 8As shown, the variable tilt angle funnel 8 is made of 12mm thick Q235B steel plate, with an open scoop type, and has an outer vertical plate 81 and an inner vertical plate 823. The outer vertical plate has dimensions of 2000mm × 15000mm × 250mm (length × width × height), and a funnel discharge port 83 is set at the front end of the outer vertical plate. The width of the funnel discharge port depends on the site conditions, and the open size should preferably be 300mm × 300mm. The inner vertical plate has dimensions of 18000mm × 13000mm × 300mm (length × width × height), with a tapered front end and a discharge port insert 89 at the tapered end. The discharge port insert 89 is closed when the grab bucket is unloading, and is opened after the wastewater in the coal slime has drained. The inner vertical plate has a vertical slit of 200mm × 10mm every 50mm to filter the wastewater in the coal in the funnel into the space between the inner and outer vertical plates. At the hopper discharge port 83, a discharge port diversion plate 831 is connected via a discharge port diversion connecting plate 832. In this embodiment, the front end of the inner and outer vertical plates of the variable tilt funnel 8 is provided with a φ120mm drain outlet, and the drain outlet is connected to a φ218mm funnel drain pipe 84 to discharge the sewage overflowing from the inner vertical plate of the funnel into the sedimentation tank. like Figure 2 As shown, in the variable tilt angle funnel 8, a coal flow diversion device 90 is provided in the direction of the feed inlet forward conveyor 7, and a coal flow merging device 91 is provided in the direction of the feed inlet reverse conveyor 7.

[0034] The function of the coal flow diversion device 90 is to spread the coal flow on the belt conveyor 7 evenly. The coal flow diversion device 90 consists of a diversion device handwheel 901, a diversion device screw 902, and a diversion device diversion plate 903. It is fixed at the front end of the variable tilt angle funnel 8, and the height of the diversion plate can be adjusted by the diversion device handwheel 901.

[0035] The function of the coal flow merging device 91 is to merge the coal slurry falling from the discharge port with the coal flow on the belt conveyor 7 in the middle to prevent overflow.

[0036] The variable tilt angle funnel 8 is fixed on the maintenance platform 9 by a hinge shaft, and the funnel hinge seat 85 is located slightly in front of the center of the funnel's longitudinal axis. The variable tilt funnel 8 is equipped with a manual lifting device at its rear end. The lifting device consists of a funnel screw 86, a screw nut, a funnel screw handwheel 87, and a bearing. The screw nut is fixed to the rear side of the variable tilt funnel 8 by a clamp. The rotating end of the lower end of the screw is interference-fitted with a bearing, and the bearing seat is fixed on the maintenance platform 9. After the sewage in the coal slurry is drained through the drain outlet, the screw handwheel is rotated according to the consistency of the coal slurry to raise the rear end of the funnel, so that the funnel forms a forward tilt angle. The variable tilt angle funnel 8 is equipped with two coal slime cleaning tools; The maintenance platform 9 spans the belt conveyor 7 and is set around the variable trough angle funnel. The platform is welded with #12 channel steel and has personnel passages paved with metal mesh panels, stairs, and 1200mm guardrails. The maintenance platform 9 has a limit bar 88 fixed at the front end of the variable tilt funnel 8 to limit the angle of the funnel tilting forward to not exceed 30°.

[0037] Example 2 This invention provides a method for treating coal slime in a sedimentation tank of a coal conveying system in a thermal power plant, comprising: The coal-containing wastewater from the coal conveying system flows into the multi-stage sedimentation and filtration tank 1 through the sedimentation tank inlet pipe 3. After natural sedimentation and filtration at each stage, the coal sludge gradually decreases while the wastewater gradually increases. When the wastewater level in the sixth-stage sedimentation tank reaches the set position, the water level sensor activates, and the wastewater is discharged from the tank by the wastewater pump 2.

[0038] When the sedimentation tank needs cleaning, the grab crane 5 is started to grab the coal sludge from the sedimentation tank. The crane travels along the track 6 to directly above the variable-angle funnel 8 above the belt conveyor 7. At this time, the screw handwheel 87 is rotated to make the variable-angle funnel 8 horizontal. The grab crane is slowly opened, and the coal sludge and sewage fall together into the inner vertical plate 82 of the funnel. The sewage flows through the intermittent vertical seams of the inner vertical plate into the space between the inner and outer vertical plates, and is discharged into the sedimentation tank through the funnel drain pipe 84. After the sewage is drained, the screw handwheel 87 is rotated to make the variable-angle funnel 8 tilt forward. At this time, the coal flow diversion device 90 of the funnel discharge port 83 touches the coal flow and separates the coal flow from the middle to both sides. Open the discharge port baffle 89. Under its own weight and the action of auxiliary tools, the coal slurry in the hopper falls onto the coal flow on the belt conveyor 7 in appropriate amount and at appropriate speed. The coal flow merging device 91 at the discharge port 83 of the hopper draws the coal flow from both sides toward the middle, covering it with coal slurry, and then discharges it into the coal storage yard along the belt. After the coal slurry is discharged, turn the handwheel 87 to restore the hopper to a horizontal state.

[0039] Notice: 1. When unloading coal slurry from the hopper, auxiliary tools must be used to control the amount of coal falling and prevent coal slurry from overflowing the conveyor belt; 2. The sedimentation tank must be cleaned only when coal is being fed onto the belt conveyor 7. The purpose is to unload the coal sludge onto the coal flow of the conveyor so as not to contaminate the belt.

[0040] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0041] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant, characterized in that, This includes multi-stage sedimentation and filtration tanks, sewage pumps, single-beam grab cranes, variable-angle funnels, and belt conveyors; The multi-stage sedimentation and filtration tank is located near the belt conveyor in the coal storage yard and is used to sediment and filter coal-containing wastewater from the coal conveying system in stages. The sewage pump is installed in the final stage sedimentation and filtration tank of the multi-stage sedimentation and filtration tank, and is used to discharge the sewage treated by the multi-stage sedimentation and filtration tank out of the tank. The single-beam grab crane is located above the multi-stage sedimentation and filtration tank and is used to grab coal slurry in the multi-stage sedimentation and filtration tank and drop the coal slurry into the variable-angle funnel. The variable tilt angle funnel is installed directly above the belt conveyor to separate wastewater from coal slurry and discharge it into a multi-stage sedimentation and filtration tank, while simultaneously unloading the coal slurry onto the coal flow of the belt conveyor. The belt conveyor is a conveyor belt used for coal blending in the coal storage yard, and it operates in both directions.

2. The coal slime treatment system for sedimentation tanks in coal conveying systems of thermal power plants according to claim 1, characterized in that, The multi-stage sedimentation and filtration tank consists of 6 filtration tanks, and the distance between the tank and the belt conveyor shall not exceed 10,000 mm. It is constructed with cement masonry, and the size is determined according to the actual site conditions. Each filtration tank shall be no less than 6,000 mm × 4,000 mm × 2,000 mm in length × width × depth. The adjacent sedimentation tanks in the multi-stage sedimentation filtration tank are connected by a 500mm wide gap, which is 500mm below the set water level, and the adjacent gaps are staggered. The first stage of the multi-stage sedimentation and filtration tank is equipped with an inlet pipe, through which coal-containing wastewater from the coal conveying system flows into the filtration tank.

3. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant according to claim 2, characterized in that, The inlet pipe of the first-stage filter tank is located 500mm above the set water level of the filter tank.

4. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant according to claim 2, characterized in that, The final stage of the multi-stage sedimentation and filtration tank is equipped with a drain pipe, through which the wastewater after multi-stage sedimentation and filtration is discharged from the system. The final stage of the multi-stage sedimentation filtration system is equipped with a water level sensor, which activates when the water level is at the highest set position and stops when it is at the lowest set position.

5. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant according to claim 4, characterized in that, The sewage pump is a 3PNL sewage pump. The inlet pipe of the sewage pump is the outlet pipe of the final stage sedimentation and filtration tank, located 500mm below the normal water level of the sedimentation tank. The sewage pump is started and stopped by a water level sensor that collects the sewage water level in the filter tank. When the sewage water level reaches the set height, the water level sensor triggers the controller to start and stop the sewage pump.

6. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant according to claim 1, characterized in that, The single-beam grab crane is located above the multi-stage sedimentation and filtration tank and is supported by columns. The track length allows the single-beam grab crane to move directly above the belt conveyor. The crane's lifting capacity should preferably be 0.75T.

7. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant according to claim 1, characterized in that, The variable tilt angle funnel is 400mm away from the lowest point of the concave surface of the coal conveyor belt, and consists of a funnel and a maintenance platform; The variable tilt angle funnel is made of 12mm thick Q235B steel plate, with an open hopper design and inner and outer double-layer vertical plates. The outer vertical plate has dimensions of 2000mm × 15000mm × 250mm (length × width × height), and a discharge port is set at the front end of the outer vertical plate. The width of the discharge port depends on the site conditions, and the open size should preferably be 300mm × 300mm. The inner vertical plate has dimensions of 18000mm × 13000mm × 300mm (length × width × height), with a tapered front end and a discharge port insert plate at the tapered end. The insert plate is closed when the grab bucket is unloading material and is opened after the wastewater in the coal slime has drained. The inner vertical plate has a vertical slit of 200mm × 10mm every 50mm to filter the wastewater in the coal in the funnel into the space between the inner and outer vertical plates.

8. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant according to claim 7, characterized in that, The variable tilt angle funnel is provided with a φ120mm drain outlet at the front end of the inner and outer vertical plates, and a φ218 drain pipe is connected below the drain outlet to discharge the sewage overflowing from the inner vertical plate of the funnel into the sedimentation tank. In the variable tilt angle funnel, a coal flow diversion device is provided in the direction of the conveyor belt at the discharge port, and a coal flow merging device is provided in the direction of the conveyor belt at the discharge port. The coal flow diversion device is used to spread the coal flow on the belt conveyor out, while the coal flow merging device is used to merge the coal slurry falling from the discharge port with the coal flow on the belt conveyor towards the middle.

9. A coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant according to claim 7, characterized in that, The variable tilt angle funnel is fixed to the maintenance platform by a hinge, with the hinge seat located slightly in front of the center of the funnel's longitudinal axis. The variable tilt angle funnel is equipped with a manual lifting device at its rear end. The lifting device consists of a lead screw, a lead screw nut, a handwheel, and a bearing. The lead screw nut is fixed to the rear side of the variable tilt angle funnel by a clamp. The rotating end of the lead screw is interference-fitted with a bearing, and the bearing seat is fixed on the maintenance platform. After the sewage in the coal slurry is drained through the drain outlet, the lead screw handwheel is rotated according to the consistency of the coal slurry to raise the rear end of the funnel, so that the funnel forms a forward tilt angle. The variable tilt angle funnel is equipped with two coal slime cleaning tools; The maintenance platform spans the belt conveyor and is set around the variable trough angle funnel. The platform is welded with #12 channel steel and has personnel passages paved with metal mesh panels, stairs, and 1200mm guardrails. The maintenance platform has a limit bar fixed at the front end of the variable tilt funnel to limit the angle of the funnel tilting forward to not exceed 30°.

10. A method for treating coal slime in a sedimentation tank of a coal conveying system in a thermal power plant, characterized in that, This method is based on a coal slime treatment system for a sedimentation tank in a coal conveying system of a thermal power plant, as described in any one of claims 1 to 9, comprising: Coal-containing wastewater from the coal conveying system flows into a multi-stage sedimentation and filtration tank through the inlet pipe of the sedimentation tank. After natural sedimentation and filtration at each stage, the coal sludge gradually decreases while the wastewater gradually increases. When the wastewater level in the sixth-stage sedimentation tank reaches the set position, the wastewater is discharged from the tank by a wastewater pump. When the sedimentation tank needs cleaning, the grab crane is started to grab the coal sludge from the sedimentation tank. The crane runs along the track to directly above the variable angle funnel above the belt conveyor. The coal sludge and sewage fall into the variable angle funnel together, and the sewage is discharged into the sedimentation tank. After the sewage is discharged, the variable angle funnel is tilted forward. The coal sludge in the variable angle funnel falls onto the coal flow on the belt conveyor under its own weight and the action of auxiliary tools, bringing the coal flow from both sides towards the middle, covering the coal sludge, and then unloading it into the coal storage yard along the belt. After the coal sludge is unloaded, the variable angle funnel is returned to a horizontal state.

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