A filter-press dewatering device for sludge treatment and a treatment process

Abstract

This application relates to a sludge dewatering equipment and process for sludge treatment, belonging to the technical field of sludge treatment. It includes a flocculation tank and a feeding assembly and a stirring assembly disposed on the flocculation tank. The feeding assembly is used to add flocculant, and the stirring assembly is used to mix the added flocculant evenly. The stirring assembly includes an axial flow cylinder coaxially disposed within the flocculation tank. The axial flow cylinder includes a axial pusher section and a vortex section fixed from top to bottom. The diameter of the axial pusher section is larger than the diameter of the vortex section, and there is a smooth transition between the axial pusher section and the vortex section. Rotatable and axially movable propulsion blades are movably disposed within the flocculation tank. The flocculation tank is also equipped with an adjusting component for adjusting the height of the propulsion blades according to sludge of different viscosities, and a driving component for driving the propulsion blades to rotate. This application has the effect of improving the uniformity of flocculant mixing and the flocculation effect of sludge, thereby improving the sludge dewatering efficiency and reducing the risk of environmental pollution from dewatered sludge.

Description

Technical Field

[0001] This application relates to the field of sludge treatment, and in particular to a sludge dewatering equipment and treatment process for sludge treatment. Background Technology

[0002] my country's municipal and industrial biochemical wastewater treatment processes produce tens of millions of tons of special sludge annually, which is enriched with recalcitrant organic matter, heavy metals, and bacterial flocs. Its environmental hazards are significantly higher than those of conventional solid waste. Therefore, the sludge needs to be treated in a harmless, stable, and resource-oriented manner, and high-standard mechanical dewatering is the core pre-process for compliant sludge disposal.

[0003] Currently, sludge is commonly dewatered using filter presses. First, the sludge is pumped into a thickening tank to increase its solids content to 3% to 5%. Then, it is pumped into a conditioning tank where a chemical cell-wall disruptor is added to break down and modify the bacterial flocs in the sludge. This removes adsorbed water trapped in the colloids, destroys the cell walls of microorganisms, releases intracellular bound water, and reduces the sludge viscosity, facilitating subsequent filter press dewatering. After the chemical cell-wall disruptor has fully reacted, a high-molecular-weight flocculant is slowly added to the sludge while simultaneously stirring the sludge rapidly to ensure the flocculant is quickly and evenly mixed. Then, the stirring speed is reduced to allow the fine particles in the sludge to collide and agglomerate into dense flocs. A frame-type agitator is typically used. Before each shift, technicians must adjust and calibrate the duration of fast and slow stirring based on process design requirements and the condition of the sludge on site to reduce the shearing effect of the agitator on the flocs. Finally, the flocculated sludge is directly pumped into the filter press via a sludge transfer pump for dewatering.

[0004] Regarding the aforementioned technologies, during the initial stage of uniform addition of flocculant and rapid mixing, the fine particles in the sludge will gradually agglomerate into small flocs. At this time, the rapidly rotating agitator easily breaks down the flocs into fine particles that are less prone to re-agglomeration. Simultaneously, due to fluctuations in the solids content of the incoming sludge and differences in the content of organic matter and bacterial flocs in the sludge solids, the viscosity of the sludge after chemical cell disruption is easily inconsistent, resulting in inconsistent sludge flowability. When the sludge flowability is too low, the flocculant may not achieve uniform mixing during the slow-mixing flocculation stage, making it difficult for some sludge to reach a sufficient concentration for flocculation. The use of flocculants can lead to some sludge flocs being too small or even not flocculated at all, and some sludge flocculants having excessively high concentrations. This results in a large amount of flocculation occurring during the rapid mixing stage, further forming a large number of fine particles that are difficult to flocculate again. Over long-term operation, this can easily clog the filter cloth, causing the sludge cake after pressure filtration and dewatering to have excessive moisture content in the core, and it is also easy for the filter cloth to adhere to. This increases the labor intensity of workers shoveling sludge and washing or replacing the filter cloth, and reduces the efficiency of sludge dewatering. Furthermore, the high-content sludge cake is prone to leachate dripping during the transfer process, causing odor diffusion and easily polluting the soil in the plant area and the surrounding surface runoff. Therefore, improvements are needed. Summary of the Invention

[0005] In order to improve the uniformity of flocculant mixing and the flocculation effect of sludge, thereby improving the efficiency of sludge dewatering by filter press and reducing the risk of environmental pollution caused by dewatered sludge, this application provides a filter press dewatering device for sludge treatment.

[0006] This application provides a sludge treatment filter press dewatering device, which adopts the following technical solution: A sludge dewatering filter press for sludge treatment includes a flocculation tank and a feeding assembly and a stirring assembly disposed on the flocculation tank. The feeding assembly is used for adding flocculant, and the stirring assembly is used for mixing the added flocculant evenly. The stirring assembly includes an axial flow cylinder coaxially disposed within the flocculation tank. The axial flow cylinder includes a axial pusher section and a swirling section fixed from top to bottom. The diameter of the axial pusher section is larger than the diameter of the swirling section, and there is a smooth transition between the axial pusher section and the swirling section. Rotatable and axially movable propulsion blades are movably disposed within the flocculation tank, and the propulsion blades are located within the axial pusher section. The flocculation tank is also provided with an adjustment component for adjusting the height of the propulsion blades for sludge of different viscosities, and a drive component for driving the propulsion blades to rotate. The feeding assembly includes multiple nozzles disposed on the swirling section. The multiple nozzles are evenly spaced along the circumference of the swirling section. The nozzles are located at the bottom of the swirling section, and the liquid outlet of the nozzles is inclined downward toward the axis of the swirling section. The nozzles are connected to an external liquid supply system.

[0007] By adopting the above technical solution, when flocculation is required, the technicians first pump the sludge treated by chemical cell disruption into the flocculation tank. At this time, the drive unit works and drives the propulsion fan blades to rotate, sucking the sludge from the top of the axial flow cylinder and guiding it to the bottom for discharge. The sludge impacts the bottom wall of the flocculation tank, causing it to flow in the annular space between the outside of the axial flow cylinder and the inside of the flocculation tank, and finally re-enter the axial flow cylinder, thereby realizing the circulation of sludge in the flocculation tank.

[0008] Then, the pre-prepared and matured flocculant is pumped into the vortex section through the nozzle via an external liquid supply system. By adding flocculant at multiple points and ensuring uniformity, the flocculant can be mixed quickly and flocculated slowly. Compared with conventional frame-type agitators, this reduces the shear force on the flocs generated during the quick mixing or slow flocculation stages.

[0009] Meanwhile, since the axial flow cylinder includes a axial push section and a vortex section fixed from top to bottom, and the diameter of the axial push section is larger than that of the vortex section, the smooth transition between the axial push section and the vortex section creates a Venturi effect when the sludge circulates. Compared with conventional axial flow agitators, this reduces the speed requirement of the propulsion blades and increases the speed of sludge flowing out of the vortex section. This further reduces the shear force of the propulsion blades on the flocs generated in the fast mixing stage or slow flocculation stage, reducing the risk of breaking the flocs into fine particles that are not easy to re-aggregate and flocculate. This improves the uniformity of flocculant mixing and the flocculation effect of sludge, thereby improving the efficiency of sludge dewatering and reducing the risk of environmental pollution from dewatered sludge.

[0010] When the sludge viscosity is too high and the fluidity is reduced, the propulsion blades are lowered by adjusting the components. This converts the increased static pressure head above the propulsion blades into the propulsion blade head. At the same time, the attenuation distance from the bottom of the swirl section to the bottom wall of the flocculation tank is shortened. This concentrates the sludge flow momentum in the high resistance zone at the bottom of the flocculation tank, thereby improving the overall circulation fluidity of the sludge and reducing the risk of reduced flocculation effect due to decreased sludge fluidity.

[0011] Optionally, the stirring assembly further includes a plurality of deflector plates disposed within the swirling section. The plurality of deflector plates are evenly spaced along the circumferential direction of the swirling section and evenly divide the swirling section into a plurality of flow-dividing chambers. The deflector plates are arranged in a spiral pattern, and the plurality of nozzles correspond one-to-one with the plurality of flow-dividing chambers.

[0012] By adopting the above technical solution, compared with conventional axial flow agitators, sludge impacts the bottom wall of the flocculation tank axially from the bottom of the axial flow tube and diffuses radially in all directions. Due to the combined effect of wall viscous resistance and adverse pressure gradient, the sludge flow velocity at the bottom wall of the flocculation tube is easily reduced. This application uses a deflector plate to make the sludge impact the bottom wall of the flocculation tank at an angle when it is discharged from the bottom of the vortex section, reducing the risk of reduced sludge flow along the wall and at the right angle between the bottom wall and the inner peripheral wall of the flocculation tank, thereby improving the uniformity of flocculant mixing. At the same time, the deflector plate applies a tangential force around the axis to the flowing sludge, making the sludge circulation asymmetrical and improving the mixing effect.

[0013] Meanwhile, when adding flocculants, the flocculants are pumped into multiple distribution chambers through nozzles, which makes it less likely for the flocculants to have excessively high local concentrations, reducing the risk of premature flocculation during the rapid mixing stage. By adding flocculants in separate zones, the flocculants are evenly dispersed in the sludge.

[0014] Optionally, the flocculation tank is provided with an inlet pipe and an outlet pipe. The outlet pipe is located at the bottom of the flocculation tank, and the bottom of the flocculation tank is conical. The inner bottom wall of the flocculation tank is provided with multiple protruding ridges, which are evenly spaced along the circumference of the flocculation tank. The protruding ridges extend along the radius of the flocculation tank to the inner circumferential wall of the outlet pipe, and the protruding ridges smoothly transition to the inner bottom wall of the flocculation tank. The outlet pipe is connected to a filter press.

[0015] By adopting the above technical solution, the convex ridges prevent sludge from easily depositing and clumping at the bottom of the flocculation tank, and the turbulence formed at the bottom wall of the flocculation tank when the sludge is tilted and impacted further reduces the risk of reduced sludge flow along the wall and at the right angle between the bottom wall and the inner peripheral wall of the flocculation tank.

[0016] Optionally, the feeding assembly further includes a guide plate disposed at the bottom of the swirling section. The guide plate is funnel-shaped, and the nozzle is rotatably disposed on the guide plate. A swing ring is rotatably disposed on the guide plate, and multiple sliding plates are slidably disposed on the swing ring. Each of the multiple sliding plates corresponds to one of the multiple nozzles. A ball head is hinged to the sliding plate. The side of the nozzle away from the liquid outlet end passes through the ball head and is slidably adapted to the ball head. A second power component for driving the swing ring to rotate is disposed on the swirling section.

[0017] By adopting the above technical solution, when adding flocculant, the set guide plate facilitates the diffusion of sludge from the swirl section to the bottom of the flocculation tank, so that the flocculant can be quickly mixed with a large amount of sludge, further reducing the risk of premature flocculation caused by excessively high local concentration of flocculant.

[0018] At the same time, the second power component works, driving the swing ring to rotate and swing back and forth. At this time, the sliding plate rotates with the swing ring and slides back and forth along the generatrix of the guide plate cone, causing the ball head to move with the sliding plate and rotate freely on the sliding plate. At this time, the side of the nozzle away from the liquid outlet slides relative to the ball head, thereby driving the nozzle to swing back and forth, thereby increasing the coverage of the flocculant spray and improving the uniformity of flocculant addition.

[0019] Optionally, the adjusting component includes a lifting ring that is raised and lowered on the flocculation tank, the propulsion blades that are coaxially rotatably mounted on the lifting ring, a first power component that drives the lifting ring to rise and fall on the flocculation tank, and a detection component that monitors the flow rate of sludge in the flocculation tank.

[0020] By adopting the above technical solution, when the detection component detects that the sludge flow rate is too low, the first power component works, driving the lifting ring and the propulsion blades to descend, thereby improving the full-area circulation fluidity of the sludge until the sludge fluidity meets the process requirements. Then, the flocculant is pumped into the flocculation tank through the external liquid supply system and the next process can be carried out.

[0021] Compared to methods that involve changing the mixing time or speed during the fast mixing and slow flocculation stages, which suffer from difficulties in precisely controlling mixing parameters and a small tolerance range for flocculation effects, the above solution adjusts the sludge flowability solely by regulating the height of the propulsion blades. This improves the uniformity of flocculant mixing and the consistency of flocculation effects.

[0022] Optionally, the detection element includes a rotating ring coaxially rotatably disposed on the outer peripheral wall of the shaft pusher. The rotating ring is provided with multiple rotating plates. The cross-section of the rotating plates is streamlined. When the sludge flows along the height direction of the shaft pusher, the flow path length of the sludge flowing through one surface of the rotating plate is greater than the flow path length of the other surface. The shaft pusher is provided with a torque sensor for detecting the rotational torque of the rotating ring. The flocculation tank is provided with a controller. The torque sensor and the first power component are both electrically connected to the controller.

[0023] By adopting the above technical solution, when flocculant needs to be added, the driving component drives the propulsion blades to rotate, realizing the circulation of sludge. When the sludge flows through the rotating plate, the cross-section of the rotating plate is streamlined. When the sludge flows along the height direction of the shaft push part, the flow path length of the sludge through one surface of the rotating plate is greater than the flow path length of the other surface, making the pressure on one side of the rotating plate less than the pressure on the other side. This causes the rotating plate to drive the rotating ring to rotate. At this time, the torque sensor installed detects the torque of the rotating ring, and after the torque sensor value stabilizes, it transmits the electrical signal to the controller.

[0024] When the value of the torque sensor is within the preset range, it indicates that the sludge fluidity is within the optimal mixing range, and flocculant can be added to the flocculation tank at this time.

[0025] When the value of the torque sensor is less than the preset range, it indicates that the sludge has low fluidity, which makes it easy for the flocculant to not be mixed evenly in the slow stirring flocculation stage. This makes it difficult for some sludge to come into contact with a sufficient concentration of flocculant, resulting in some sludge flocs being too small or even not flocculated at all. It also causes some sludge to have an excessively high flocculant concentration, resulting in a large amount of flocculation in the fast stirring mixing stage, which easily forms a large number of fine particles that are difficult to flocculate again. At this time, the controller activates the first power component to achieve the descent of the propulsion blades.

[0026] Compared to conventional methods that directly detect sludge flowability using flow rate sensors, or calculate sludge viscosity by detecting sludge solids content and pH value after chemical cell disruption, and indirectly calculate sludge flowability, this method reduces the impact of significant differences in detection values ​​at different detection points, and improves the representativeness and accuracy of sludge flowability detection results.

[0027] Optionally, the outer peripheral wall of the swirl section is provided with multiple baffles, which are evenly distributed at intervals along the outer peripheral wall of the swirl section. The baffles are located below the rotating plate, and the number of baffles is the same as that of the rotating plate, and they are staggered with the rotating plate. One end of the baffle near the rotating plate is connected to the inner peripheral wall of the flocculation tank, and the other end of the baffle has a gap with the inner peripheral wall of the flocculation tank.

[0028] By adopting the above technical solution, when the sludge rises from the bottom of the vortex section, the baffle plate guides the sludge to rise, and at the same time, the upward-flowing sludge collides with the baffle plate, which enhances the effect of fine particles colliding and agglomerating into dense flocs during the slow stirring and flocculation stage.

[0029] When the sludge rises and flows past the rotating plate, the end of the baffle plate closest to the rotating plate is connected to the inner wall of the flocculation tank, which makes the sludge flow in the same direction as the rotating plate. This reduces the risk of deviation in the torque sensor detection value caused by irregular sludge flow. At the same time, since the end of the baffle plate away from the rotating plate has a gap with the inner wall of the flocculation tank, it is not easy to obstruct the flow of sludge at the bottom of the flocculation tank, thus improving the uniformity of flocculant mixing.

[0030] On the other hand, this application provides a sludge dewatering process using filter press, comprising the following steps: S1: The sludge to be treated is transported to a thickening tank for gravity thickening treatment, so that the solid content of the sludge is increased to 3%-5%; S2: The concentrated sludge is transported to the conditioning tank, and high-pressure pulse cell disruption is performed on it during the sludge transport process. Then, desulfurization ash and sulfur are added to the conditioning tank as chemical cell disruptors, and the mixture is stirred and reacted to modify the bacterial flocs in the sludge and release intracellular bound water. S3: Pump the sludge after cell wall breaking into the flocculation tank. Then, the technicians start the equipment. The drive unit works to drive the propulsion blades to rotate, realizing the circulation of the sludge. At the same time, the controller makes the first power unit work, so that the value of the torque sensor after stabilization is within the preset range, thereby ensuring the consistency of the sludge flowability. S4: The pre-prepared matured flocculant is pumped into the diversion chamber through the nozzle by the external liquid supply system. At the same time, the propulsion blades work continuously for the duration required by the process, and the speed of the propulsion blades in the fast mixing stage and the slow flocculation stage is adjusted to achieve sludge flocculation. S5: The flocculated sludge is pumped into a filter press, where solid-liquid separation is achieved through the pressure of the filter press, thus realizing the sludge dewatering treatment.

[0031] In summary, this application includes at least one of the following beneficial technical effects: 1. When the sludge and flocculant are mixed evenly, the drive unit operates and drives the propeller blades to rotate, sucking the sludge from the top of the axial flow cylinder and guiding it to the bottom for discharge. Finally, the sludge re-enters the axial flow cylinder, realizing the circulation of sludge in the flocculation tank. Compared with conventional frame-type agitators, this reduces the shear force on the flocs generated in the fast mixing or slow flocculation stages. At the same time, the sludge circulation creates a Venturi effect, reducing the speed requirement of the propeller blades compared with conventional axial flow agitators, while increasing the speed of sludge flowing out of the vortex section. This further reduces the shear force of the propeller blades on the flocs generated in the fast mixing or slow flocculation stages, reducing the risk of breaking the flocs into fine particles that are not easy to re-aggregate and flocculate. This improves the uniformity of flocculant mixing and the flocculation effect of sludge, thereby improving the sludge dewatering efficiency and reducing the risk of environmental pollution from dewatered sludge. 2. Before adding flocculant, the drive unit drives the propulsion blades to rotate, realizing the circulation of sludge. When the sludge flows through the rotating plate, the rotating plate causes the rotating ring to rotate. At this time, the torque sensor installed detects the torque of the rotating ring, and after the torque sensor value stabilizes, the electrical signal is transmitted to the controller. When the value of the torque sensor is within the preset range, it indicates that the sludge fluidity is within the optimal mixing range, and flocculant can be added into the flocculation tank at this time. When the value of the torque sensor is less than the preset range, it indicates that the sludge has low fluidity, which makes it easy for the flocculant to not be mixed evenly in the slow stirring flocculation stage. At this time, the controller activates the first power component, driving the lifting ring and the propulsion blades to descend. This converts the increased static pressure head above the propulsion blades into the propulsion blade head, and at the same time shortens the attenuation distance of the jet from the bottom of the swirl section to the bottom wall of the flocculation tank. This concentrates the sludge flow momentum in the high resistance area at the bottom of the flocculation tank to improve the overall circulation fluidity of the sludge until the value of the torque sensor stabilizes within the preset range. At this time, flocculant is added to the flocculation tank. Compared with changing the stirring time or stirring speed of the fast stirring mixing stage and the slow stirring flocculation stage, which has the problem of difficulty in accurately adjusting the stirring parameters and a small tolerance range for flocculation effect, the above solution only adjusts the height of the propulsion blades to adjust the fluidity of the sludge, thereby improving the uniformity of flocculant mixing and the consistency of flocculation effect. 3. Compared to conventional axial flow mixers, sludge impacts the bottom wall of the flocculation tank axially from the bottom of the axial flow cylinder and diffuses radially in all directions. Due to the combined effect of wall viscous resistance and adverse pressure gradient, the sludge flow velocity at this point tends to decrease rapidly. This application uses a deflector plate to make the sludge impact the bottom wall of the flocculation tank at an angle when it is discharged from the bottom of the vortex section. The protruding ridges prevent the sludge from depositing and agglomerating at the bottom of the flocculation tank and create turbulence at the bottom wall of the flocculation tank when the sludge impacts at an angle. This reduces the risk of reduced sludge flowability along the wall and at the right angle between the bottom wall and the inner peripheral wall of the flocculation tank, thereby improving the uniformity of flocculant mixing. At the same time, the deflector plate applies a tangential force around the axis to the flowing sludge, making the sludge circulation asymmetrical and improving the mixing effect. 4. The flocculant is pumped into the distribution chamber from the nozzle through an external liquid supply system, which makes it less likely for the flocculant concentration to be too high in certain areas, reducing the risk of premature flocculation during the rapid mixing stage. By adding flocculant in sections, the flocculant is evenly dispersed in the sludge. At the same time, the second power component works, driving the swing ring to rotate and swing back and forth, which in turn drives the sliding plate and ball head to move, thereby driving the nozzle to swing back and forth, thus increasing the coverage area of ​​the flocculant spray and improving the uniformity of flocculant addition. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 This is a schematic diagram of the connection structure of the axial flow tube, propulsion blades, and flocculation tank; Figure 3 This is a schematic diagram of the connection structure of the nozzle, swing ring, sliding plate and ball head; Figure 4 yes Figure 2 A magnified view of part A in the diagram.

[0033] Reference numerals: 1. Flocculation tank; 11. Controller; 12. Protruding rib; 13. Baffle plate; 14. Feed pipe; 15. Discharge pipe; 16. Isolation cover; 2. Stirring assembly; 21. Axial flow cylinder; 211. Shaft thrust section; 212. Swirl section; 22. Propeller blade; 23. Adjusting component; 231. Lifting ring; 232. First power component; 24. Detection component; 241. Rotating ring; 242. Rotating plate; 243. Torque sensor; 25. Drive component; 26. Deflector plate; 27. Diverter chamber; 3. Feeding assembly; 31. Nozzle; 32. Guide plate; 33. Swinging ring; 34. Sliding plate; 35. Ball head; 36. Second power component; 4. Conveying pump; 5. Filter press. Detailed Implementation

[0034] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail below.

[0035] This application discloses a filter press dewatering device for sludge treatment.

[0036] Reference Figure 1 A sludge treatment filter press dewatering device includes a flocculation tank 1 fixed on the ground and a filter press 5. The flocculation tank 1 is provided with an inlet pipe 14 and an outlet pipe 15. The outlet pipe 15 is located at the bottom of the flocculation tank 1 and is connected to the filter press 5. A conveying pump 4 for pumping the sludge in the flocculation tank 1 into the filter press 5 is fixed on the outlet pipe 15. The conveying pump 4 in this application is a screw pump to reduce the shearing of the flocs.

[0037] To ensure uniform mixing of the flocculant and reduce the risk of breaking up the flocs, a stirring assembly 2 is installed on the flocculation tank 1, as described above. Figure 2 The stirring assembly 2 includes an axial flow cylinder 21 coaxially fixed inside the flocculation tank 1. The axial flow cylinder 21 includes a axial pusher 211 and a vortex section 212 fixed from top to bottom. The diameter of the axial pusher 211 is larger than the diameter of the vortex section 212. The axial pusher 211 and the vortex section 212 are smoothly transitioned. A rotatable and axially movable propulsion blade 22 is movably arranged inside the flocculation tank 1. The propulsion blade 22 is located inside the axial pusher 211. The rotation axis of the propulsion blade 22 is consistent with the height direction of the flocculation tank 1. A drive component 25 is provided on the flocculation tank 1 to drive the propulsion blade 22 to rotate. In this application, the drive component 25 is a geared motor.

[0038] Furthermore, in order to improve the fluidity of the sludge, refer to Figure 2 The bottom of the swirl section 212 has a gap with the inner bottom wall of the flocculation tank 1. The bottom of the flocculation tank 1 is conical. Multiple protruding ribs 12 are fixed on the inner bottom wall of the flocculation tank 1. The multiple protruding ribs 12 are evenly distributed along the circumference of the flocculation tank 1. The protruding ribs 12 extend along the radius of the flocculation tank 1 to the inner circumferential wall of the discharge pipe 15. The protruding ribs 12 and the inner bottom wall of the flocculation tank 1 are smoothly transitioned. In this application, there are twenty protruding ribs 12. In other embodiments, depending on the size of the flocculation tank 1, there may be two, three, ten or more protruding ribs 12. The arrangement method can be the same as in this application.

[0039] In order to deflect the sludge in the swirl section 212 and improve the mixing effect of the rapid mixing stage, refer to Figure 2 The stirring assembly 2 also includes a plurality of deflector plates 26 fixed in the swirling section 212. The plurality of deflector plates 26 are evenly spaced along the circumference of the swirling section 212 and evenly divide the swirling section 212 into a plurality of flow-dividing chambers 27. The deflector plates 26 are arranged in a spiral. In this application, there are eight deflector plates 26. In other embodiments, depending on the size of the swirling section 212, there may be two, three, five or more deflector plates 26. The arrangement can be the same as in this application.

[0040] When flocculation is required, the technicians first pump the chemically broken sludge into the flocculation tank 1 through the feed pipe 14. Then, the technicians start the equipment. At this time, the drive unit 25 works and drives the propeller blades to rotate, sucking the sludge from the top of the axial flow cylinder 21 and guiding it to the bottom for discharge. The sludge impacts the bottom wall of the flocculation tank 1, causing it to flow in the annular space between the outside of the axial flow cylinder 21 and the inside of the flocculation tank 1, and finally re-enter the axial flow cylinder 21, thereby realizing the circulation of sludge in the flocculation tank 1. Then, the technicians add flocculant, and at the same time, the propeller blades 22 work continuously for the duration required by the process, adjusting the speed of the fast mixing stage and the slow flocculation stage of the propeller blades 22. Then, the flocculated sludge is pumped into the filter press 5 for dewatering by the screw pump.

[0041] When agitating the flocculant, compared to conventional frame-type agitators, the shear force on the flocs generated during the fast mixing or slow flocculation stages is reduced. Furthermore, since the axial flow cylinder 21 includes a axial pusher section 211 and a vortex section 212 fixed sequentially from top to bottom, with the diameter of the axial pusher section 211 being larger than that of the vortex section 212, the smooth transition between the axial pusher section 211 and the vortex section 212 creates a Venturi effect during sludge circulation. Compared to conventional axial flow agitators, this reduces the required rotational speed of the propulsion blades 22 while increasing the velocity of the sludge flowing out of the vortex section 212. This further reduces the shear force exerted by the propulsion blades 22 on the flocs generated during the fast mixing or slow flocculation stages, reducing the risk of breaking the flocs into fine particles that are difficult to re-aggregate and flocculate. This improves the uniformity of flocculant mixing and the flocculation effect of the sludge, thereby increasing the efficiency of sludge dewatering and reducing the risk of environmental pollution from dewatered sludge.

[0042] Compared to conventional axial flow mixers, where sludge impacts the bottom wall of the flocculation tank 1 axially from the bottom of the axial flow cylinder 21 and diffuses radially outwards, the combined effect of wall viscosity resistance and adverse pressure gradient easily causes the sludge flow velocity to decrease rapidly. This application uses a deflector plate 26 to make the sludge impact the bottom wall of the flocculation tank 1 at an angle when discharged from the bottom of the swirl section 212. The protruding ribs 12 prevent the sludge from depositing and agglomerating at the bottom of the flocculation tank 1 and reduce the risk of reduced sludge flow along the wall and at the right angle between the bottom wall and the inner peripheral wall of the flocculation tank 1. This improves the uniformity of flocculant mixing. At the same time, the deflector plate 26 applies a tangential force around the axis to the flowing sludge, making the sludge circulation asymmetrical and improving the mixing effect.

[0043] Furthermore, in order to adjust the height of the propulsion blades 22 for sludge of different viscosities, the flocculation tank 1 is equipped with an adjusting component 23, as shown in the figure. Figure 2The adjusting component 23 includes a lifting ring 231 that is lifted and connected to the flocculation tank 1. The propulsion blade 22 is coaxially rotatably connected to the lifting ring 231. The flocculation tank 1 is provided with a first power component 232 that drives the lifting ring 231 to lift and lower. In this application, the first power component 232 is a hydraulic cylinder. In order to improve the stability of the lifting ring 231, two first power components 232 are symmetrically provided.

[0044] To monitor the flow rate of sludge within flocculation tank 1, a detection element 24 is installed on flocculation tank 1, referring to... Figure 2 The detection element 24 includes a rotating ring 241 coaxially rotatably connected to the outer peripheral wall of the shaft pusher 211. Multiple rotating plates 242 are fixed on the rotating ring 241. The cross-section of the rotating plates 242 is streamlined. When the sludge flows along the height direction of the shaft pusher 211, the flow path length of the sludge through one surface of the rotating plate 242 is greater than the flow path length of the other surface. A torque sensor 243 for detecting the rotation torque of the rotating ring 241 is fixed on the shaft pusher 211. A controller 11 is provided on the flocculation tank 1. The torque sensor 243 and the first power component 232 are electrically connected to the controller 11.

[0045] When flocculant needs to be added, the drive component 25 drives the propulsion blade 22 to rotate, realizing the circulation of sludge. When the sludge flows through the rotating plate 242, since the cross-section of the rotating plate 242 is streamlined, and when the sludge flows along the height direction of the shaft push part 211, the flow path length of the sludge flowing through one surface of the rotating plate 242 is greater than the flow path length of the other surface, so that the pressure on one side of the rotating plate 242 is less than the pressure on the other side, thereby causing the rotating plate 242 to drive the rotating ring 241 to rotate. At this time, the torque sensor 243 is installed to detect the torque of the rotating ring 241, and after the value of the torque sensor 243 stabilizes, the electrical signal is transmitted to the controller 11.

[0046] When the value of torque sensor 243 is within the preset range, it indicates that the sludge fluidity is within the optimal mixing range, and flocculant can be added to flocculation tank 1 at this time.

[0047] When the value of torque sensor 243 is less than the preset range, it indicates that the sludge has low fluidity, which makes it easy for the flocculant to not be mixed evenly in the slow stirring flocculation stage. This makes it difficult for some sludge to come into contact with a sufficient concentration of flocculant, resulting in some sludge flocs being too small or even not flocculated. It also causes some sludge to have an excessively high flocculant concentration, resulting in a large amount of flocculation in the fast stirring mixing stage, which easily forms a large number of fine particles that are difficult to flocculate again. At this time, controller 11 activates the first power component 232, driving the lifting ring 231 and the propulsion blade 22 to descend. This converts the increased static pressure head above the propulsion blade 22 into the propulsion blade 22 head, and at the same time shortens the attenuation distance of the jet from the bottom of the swirl section 212 to the bottom wall of the flocculation tank 1. This concentrates the sludge flow momentum in the high resistance area at the bottom of the flocculation tank 1 to improve the overall circulation fluidity of the sludge until the value of torque sensor 243 stabilizes within the preset range. At this time, flocculant can be added to the flocculation tank 1.

[0048] When the sludge has poor flowability, compared to changing the mixing time or speed of the fast mixing stage and the slow flocculation stage, it is difficult to accurately adjust the mixing parameters and the flocculation effect has a small tolerance range. The above solution only adjusts the height of the propulsion blade 22 to adjust the flowability of the sludge, thereby improving the uniformity of flocculant mixing and the consistency of flocculation effect.

[0049] Compared to conventional methods that directly detect sludge flowability using flow rate sensors, or calculate sludge viscosity by detecting sludge solids content and pH value after chemical cell disruption, and indirectly calculate sludge flowability, this method reduces the impact of significant differences in detection values ​​at different testing points, and improves the representativeness and accuracy of sludge flowability test results.

[0050] To improve the flocculation effect, refer to Figure 2 Multiple baffles 13 are fixed on the outer peripheral wall of the swirl section 212. The multiple baffles 13 are evenly distributed at intervals along the outer peripheral wall of the swirl section 212. The baffles 13 are located below the rotating plate 242. The number of baffles 13 is the same as that of the rotating plate 242, and they are arranged alternately with the rotating plate 242. One end of the baffle 13 near the rotating plate 242 is flat and connected to the inner peripheral wall of the flocculation tank 1. The other end of the baffle 13 is continuously serrated and has a gap with the inner peripheral wall of the flocculation tank 1. In this application, there are eight rotating plates 242 and eight baffles 13. In other embodiments, depending on the size of the axial flow cylinder 21, there can also be two, three, five, or more rotating plates 242 and baffles 13. The arrangement can be the same as in this application.

[0051] When the sludge rises from the bottom of the vortex section 212, the baffle plate 13 guides the sludge to rise and causes the upward-flowing sludge to collide with the baffle plate 13. During the slow stirring and flocculation stage, the effect of fine particles colliding and agglomerating into dense flocs is enhanced.

[0052] When the sludge rises and flows through the rotating plate 242, the end of the baffle plate 13 near the rotating plate 242 is connected to the inner peripheral wall of the flocculation tank 1, so that the sludge flows in the same direction as the rotating plate 242. This reduces the risk of deviation in the detection value of the torque sensor 243 caused by irregular sludge flow. At the same time, since the end of the baffle plate 13 away from the rotating plate 242 leaves a gap with the inner peripheral wall of the flocculation tank 1, it is not easy to obstruct the flow of sludge at the bottom of the flocculation tank 1, thus improving the uniformity of flocculant mixing.

[0053] Furthermore, to facilitate uniform addition of flocculant and improve the mixing uniformity of flocculant, the flocculation tank 1 is equipped with a feeding component 3, as shown in the figure. Figure 3 and Figure 4 The feeding assembly 3 includes a guide plate 32 fixed to the bottom of the swirling section 212. The guide plate 32 is trumpet-shaped and has multiple nozzles 31 rotatably connected to it. The multiple nozzles 31 are evenly spaced along the circumference of the swirling section 212. Each nozzle 31 corresponds to a multiple diversion chamber 27. The liquid outlet end of the nozzle 31 is inclined downward toward the axis of the swirling section 212. The rotation axis of the nozzle 31 is parallel to the generatrix of the cone of the guide plate 32. The nozzle 31 is connected to an external liquid supply system through a hose.

[0054] A swing ring 33 is rotatably connected to the guide plate 32. The rotation axis of the swing ring 33 is consistent with the rotation axis of the propulsion fan blade. Multiple sliding plates 34 are slidably arranged on the swing ring 33. The sliding direction of the sliding plates 34 is parallel to the generatrix of the cone of the guide plate 32. The multiple sliding plates 34 correspond one-to-one with multiple nozzles 31. In this application, there are eight sliding plates 34 and eight nozzles 31. A ball head 35 is hinged on the sliding plate 34. The ball head 35 and the sliding plate 34 are spherically hinged. The side of the nozzle 31 away from the liquid outlet end is arranged through the ball head 35 and is slidably adapted to the ball head 35. A second power member 36 for driving the swing ring 33 to rotate is provided on the swirling part 212. In this application, the second power member 36 is an electric push rod. The output end of the electric push rod is rotatably connected to the swing ring 33. The cylinder of the electric push rod is rotatably connected to the swirling part 212.

[0055] In order to reduce the impact of sludge on the operation of the second power component 36 and reduce the obstruction of sludge flowing through the outer peripheral wall of the axial flow cylinder 21, an isolation cover 16 is fixed on the outside of the swirl section 212 to cover and isolate the nozzle 31, the swing ring 33, the sliding plate 34 and the ball head 35.

[0056] When adding flocculant, the external liquid supply system pumps the pre-prepared and matured flocculant into the diversion chamber 27 through the nozzle 31, making it less likely for the flocculant to have excessively high local concentrations, reducing the risk of premature flocculation during the rapid mixing stage. By adding flocculant in sections, the flocculant is evenly dispersed in the sludge. At the same time, the guide plate 32 facilitates the diffusion of sludge from the swirl section 212 to the bottom of the flocculation tank 1, allowing the flocculant to mix quickly with a large amount of sludge, further reducing the risk of premature flocculation due to excessively high local concentrations of flocculant.

[0057] Simultaneously, the second power component 36 operates, driving the swing ring 33 to rotate and swing back and forth. At this time, the sliding plate 34 rotates with the swing ring 33 and slides back and forth along the generatrix of the cone of the guide plate 32, causing the ball head 35 to move with the sliding plate 34 and rotate freely on the sliding plate 34. At this time, the side of the nozzle 31 away from the liquid outlet slides relative to the ball head 35, thereby driving the nozzle 31 to swing back and forth, thereby increasing the coverage of the flocculant spray and improving the uniformity of flocculant addition.

[0058] The implementation principle of a sludge dewatering equipment for sludge treatment in this application embodiment is as follows: When flocculation is required, the technician first pumps the sludge after chemical cell disruption treatment into the flocculation tank 1 through the feed pipe 14. Then the technician starts the equipment. At this time, the drive component 25 works and drives the propulsion fan blade to rotate, so as to realize the circulation of sludge in the flocculation tank 1.

[0059] At this time, the sludge flows through the rotating plate 242. Since the cross-section of the rotating plate 242 is streamlined, the flow path length of the sludge through one surface of the rotating plate 242 is greater than the flow path length of the other surface. This makes the pressure on one side of the rotating plate 242 less than the pressure on the other side, so that the rotating plate 242 drives the rotating ring 241 to rotate. At this time, the torque sensor 243 is installed to detect the torque of the rotating ring 241, and after the value of the torque sensor 243 stabilizes, the electrical signal is transmitted to the controller 11.

[0060] When the value of torque sensor 243 is within the preset range, it indicates that the sludge fluidity is within the optimal mixing range. At this time, the pre-prepared matured flocculant can be pumped into the flocculation tank 1 through nozzle 31 via the external liquid supply system.

[0061] When the value of torque sensor 243 is less than the preset range, it indicates that the sludge has low fluidity, which makes it easy for the flocculant to not be mixed evenly during the slow stirring flocculation stage. At this time, controller 11 activates the first power component 232, which drives the lifting ring 231 and the propulsion blade 22 to descend, so that the increased static pressure head above the propulsion blade 22 is converted into the propulsion blade 22 head. At the same time, it shortens the attenuation distance of the jet from the bottom of the swirl section 212 to the bottom wall of the flocculation tank 1, and concentrates the sludge flow momentum in the high resistance area at the bottom of the flocculation tank 1 to improve the sludge circulation fluidity throughout the entire area until the value of torque sensor 243 stabilizes within the preset range. At this time, flocculant can be added to the flocculation tank 1.

[0062] When the flocculant is added, the second power component 36 works synchronously, driving the swing ring 33 to swing back and forth, and in turn driving the sliding plate 34 and the ball head 35 to move, thereby driving the nozzle 31 to swing back and forth, thus increasing the coverage of the flocculant spray.

[0063] Simultaneously, the propulsion blades 22 continue to work for the preset duration according to the process requirements, and the speed of the propulsion blades 22 in the fast mixing stage and the slow flocculation stage is adjusted to achieve sludge flocculation. Then, the flocculated sludge is pumped into the filter press 5 for filter dewatering by a screw pump.

[0064] This application discloses a filtration dewatering process for sludge treatment. Based on a filtration dewatering device for sludge treatment, the process includes the following steps: S1: The sludge to be treated is transported to a thickening tank for gravity thickening treatment, so that the solid content of the sludge is increased to 3%-5%; S2: The concentrated sludge is transported to the conditioning tank, and high-pressure pulse cell disruption is performed on it during the sludge transport process. Then, desulfurization ash and sulfur are added to the conditioning tank as chemical cell disruptors, and the mixture is stirred and reacted to modify the bacterial flocs in the sludge and release intracellular bound water. S3: The sludge after cell wall breaking treatment is pumped into the flocculation tank 1. Then the technician starts the equipment. The drive component 25 works to drive the propulsion blade 22 to rotate, realizing the circulation of sludge. At the same time, the controller 11 makes the first power component 232 work, so that the value of the torque sensor 243 after stabilization is within the preset range, thereby ensuring the consistency of the sludge material flowability. S4: The pre-prepared matured flocculant is pumped into the diversion chamber 27 through the nozzle 31 by the external liquid supply system. At the same time, the propulsion blade 22 works continuously for the duration required by the process, and the speed of the propulsion blade 22 in the fast mixing stage and the slow flocculation stage is adjusted to achieve sludge flocculation. S5: The flocculated sludge is pumped into the filter press 5, and the solid-liquid separation is completed by the pressure of the filter press 5, so as to achieve sludge dewatering treatment by filter pressing.

[0065] The above are all optional embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A filter press dewatering device for sludge treatment, characterized in that: It includes a flocculation tank (1) and a feeding component (3) and a stirring component (2) disposed on the flocculation tank (1). The feeding component (3) is used to add flocculant, and the stirring component (2) is used to mix the added flocculant evenly. The stirring assembly (2) includes an axial flow cylinder (21) coaxially disposed in the flocculation tank (1). The axial flow cylinder (21) includes a axial pusher (211) and a vortex section (212) fixed from top to bottom. The diameter of the axial pusher (211) is larger than the diameter of the vortex section (212). The axial pusher (211) and the vortex section (212) are smoothly transitioned. The flocculation tank (1) is movably provided with a rotatable and axially movable propulsion blade (22), and the propulsion blade (22) is located in the axial pusher (211). The flocculation tank (1) is also provided with an adjustment component (23) for adjusting the height of the propulsion blade (22) for sludge of different viscosities and a drive component (25) for driving the propulsion blade (22) to rotate. The feeding assembly (3) includes a plurality of nozzles (31) disposed on the swirling section (212). The plurality of nozzles (31) are evenly spaced along the circumferential direction of the swirling section (212). The nozzles (31) are located at the bottom of the swirling section (212), and the liquid outlet end of the nozzles (31) is inclined downward toward the axis of the swirling section (212). The nozzles (31) are connected to an external liquid supply system.

2. The sludge dewatering equipment for sludge treatment according to claim 1, characterized in that: The stirring assembly (2) further includes a plurality of deflector plates (26) disposed in the swirling section (212). The plurality of deflector plates (26) are evenly spaced along the circumferential direction of the swirling section (212) and evenly divide the swirling section (212) into a plurality of flow-dividing chambers (27). The deflector plates (26) are arranged in a spiral. The plurality of nozzles (31) correspond one-to-one with the plurality of flow-dividing chambers (27).

3. The sludge dewatering equipment for sludge treatment according to claim 2, characterized in that: The flocculation tank (1) is provided with a feed pipe (14) and a discharge pipe (15). The discharge pipe (15) is located at the bottom of the flocculation tank (1), and the bottom of the flocculation tank (1) is conical. The inner bottom wall of the flocculation tank (1) is provided with a plurality of protruding ridges (12). The plurality of protruding ridges (12) are evenly spaced along the circumference of the flocculation tank (1). The protruding ridges (12) extend along the radius of the flocculation tank (1) to the inner circumferential wall of the discharge pipe (15), and the protruding ridges (12) and the inner bottom wall of the flocculation tank (1) are smoothly transitioned. The discharge pipe (15) is connected to the filter press (5).

4. The sludge dewatering equipment for sludge treatment according to claim 3, characterized in that: The feeding assembly (3) also includes a guide plate (32) located at the bottom of the swirling section (212). The guide plate (32) is horn-shaped. The nozzle (31) is rotatably mounted on the guide plate (32). A swing ring (33) is rotatably mounted on the guide plate (32). Multiple sliding plates (34) are slidably mounted on the swing ring (33). The multiple sliding plates (34) correspond one-to-one with the multiple nozzles (31). A ball head (35) is hinged on the sliding plate (34). The side of the nozzle (31) away from the liquid outlet is arranged through the ball head (35) and is slidably adapted to the ball head (35). A second power component (36) is provided on the swirling section (212) to drive the swing ring (33) to rotate.

5. A filter press dewatering device for sludge treatment according to claim 4, characterized in that: The regulating component (23) includes a lifting ring (231) that is lifted and lowered on the flocculation tank (1), the propulsion blade (22) is coaxially rotatably mounted on the lifting ring (231), the flocculation tank (1) is provided with a first power component (232) that drives the lifting ring (231) to rise and fall, and the flocculation tank (1) is also provided with a detection component (24) for monitoring the flow rate of sludge in the flocculation tank (1).

6. The sludge dewatering equipment for sludge treatment according to claim 5, characterized in that: The detection component (24) includes a rotating ring (241) coaxially rotatably disposed on the outer peripheral wall of the shaft pusher (211). The rotating ring (241) is provided with multiple rotating plates (242). The cross section of the rotating plate (242) is streamlined. When the sludge flows along the height direction of the shaft pusher (211), the flow path length of the sludge flowing through one surface of the rotating plate (242) is greater than the flow path length of the other surface. The shaft pusher (211) is provided with a torque sensor (243) for detecting the rotation torque of the rotating ring (241). The flocculation tank (1) is provided with a controller (11). The torque sensor (243) and the first power component (232) are both electrically connected to the controller (11).

7. A filter press dewatering device for sludge treatment according to claim 6, characterized in that: Multiple baffles (13) are provided on the outer peripheral wall of the swirling section (212). The multiple baffles (13) are evenly distributed at intervals along the outer peripheral wall of the swirling section (212). The baffles (13) are located below the rotating plate (242). The number of baffles (13) is the same as that of the rotating plate (242), and they are arranged alternately with the rotating plate (242). One end of the baffle (13) close to the rotating plate (242) is connected to the inner peripheral wall of the flocculation tank (1), and the other end of the baffle (13) has a gap with the inner peripheral wall of the flocculation tank (1).

8. A sludge treatment process using filter press dewatering, employing a sludge treatment filter press dewatering device as described in any one of claims 1-7, characterized in that: The following steps are adopted: S1: The sludge to be treated is transported to a thickening tank for gravity thickening treatment, so that the solid content of the sludge is increased to 3%-5%; S2: The concentrated sludge is transported to the conditioning tank, and high-pressure pulse cell disruption is performed on it during the sludge transport process. Then, desulfurization ash and sulfur are added to the conditioning tank as chemical cell disruptors, and the mixture is stirred and reacted to modify the bacterial flocs in the sludge and release intracellular bound water. S3: Pump the sludge after the cell wall breaking treatment into the flocculation tank (1), and then the technicians start the equipment. The drive component (25) works to drive the propulsion blade (22) to rotate, so as to realize the circulation of sludge. At the same time, the controller (11) makes the first power component (232) work, so that the value of the torque sensor (243) after stabilization is within the preset range, thereby ensuring the consistency of the sludge material flowability. S4: The pre-prepared matured flocculant is pumped into the diversion chamber (27) through the nozzle (31) by the external liquid supply system. At the same time, the propulsion blade (22) works continuously for the duration required by the process, and the speed of the propulsion blade (22) in the fast mixing stage and the slow flocculation stage is adjusted to achieve sludge flocculation. S5: The flocculated sludge is pumped into the filter press (5), and solid-liquid separation is completed by the pressure of the filter press (5), so as to achieve sludge dewatering treatment by filter pressing.

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