Sludge filtration system for sewage treatment plants

Abstract

The utility model belongs to sewage treatment technical field, concretely relates to a sewage treatment station sludge filtration system. The sewage treatment station sludge filtration system, including sludge conditioning tank, sludge conditioning tank is connected with the treatment jar through sludge delivery pump, and the treatment jar is connected with the plate and frame filter press through the feed pump, and the plate and frame filter press bottom filtrate export place is provided with filtrate discharge valve, and the filtrate discharge valve is connected with the filter behind, and the filter export is provided with the pipeline that is connected with filtrate pool and pickling solution storage tank respectively. The sewage treatment station sludge filtration system of the utility model, through the design optimization sludge pretreatment and filter pressing process such as treatment jar heating stirring, pH detection dosing, on-line pressure monitoring, realizes resource utilization using pickling solution and filtrate circulation, combines abnormal condition automatic shutdown, pressure relief, pollution backflow and backwashing mechanism guarantee safety and stable operation, and has the advantages of improving treatment efficiency, reducing cost, enhancing environmental protection and operation flexibility.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment technology, specifically relating to a sludge filtration system for a wastewater treatment plant. Background Technology

[0002] In the wastewater treatment industry, the efficient treatment and disposal of sludge is a crucial link in ensuring ecological and environmental safety and sustainable resource utilization. Sludge is characterized by high water content and large volume. Sludge that has not undergone effective dewatering treatment not only occupies a large amount of land resources, but the heavy metals, pathogens, and organic pollutants it contains can also easily spread in the environment, causing serious pollution to soil, water bodies, and the atmosphere.

[0003] Belt filter press and plate and frame filter press are common technologies for sludge dewatering. While belt filter press offers the advantage of continuous processing, its stringent requirement of a solids content of at least 50% for the feed sludge limits its application in certain sludge treatment scenarios. Furthermore, the moisture content of the effluent after this process is generally still around 82%, making it difficult to meet the needs of subsequent advanced treatment and resource utilization. While plate and frame filter press can reduce the moisture content of sludge to 65%-75%, it requires frequent manual cleaning of the filter cloth and plates. Otherwise, filter cloth blockage can occur, leading to increased energy consumption and component wear. Replacement operations are not only time-consuming and labor-intensive but also increase labor costs and affect the safety of the production environment. In addition, due to the effects of wastewater treatment, sludge viscosity can be high, which exacerbates the energy consumption of the plate and frame filter press, resulting in a significant decrease in filtration efficiency. Therefore, it is necessary to further optimize the sludge filtration system in existing wastewater treatment technologies to achieve filter cloth cleaning while ensuring low sludge moisture content, thus guaranteeing the safety and rationality of the operating environment.

[0004] CN222250381U discloses a sludge dewatering filter press, including a main body, a storage chamber, a filter cylinder, a drive component, and a circulation component. The storage chamber is located below the main body's outlet pipe, containing the filter cylinder. The drive component rotates the filter cylinder, and the circulation component draws water from the bottom of the storage chamber and sprays it onto the filter cylinder for secondary filtration. When the water hits the rotating filter cylinder, impurities are filtered out, and the water flows into the drain pipe for discharge. Splashed water is pumped back for further filtration by the circulation component. This device, with its bottom-mounted filter cylinder, can directly filter impurities from the discharged water when the filter cloth is damaged, eliminating the need for secondary treatment and improving work efficiency. Support wheels ensure stable rotation of the filter cylinder, and the circulation component washes the filter cylinder, maintaining filtration effectiveness. However, the device has a relatively complex structure. Components such as the drive motor and water pump increase equipment cost and energy consumption. Furthermore, if the filter cylinder becomes clogged, manual cleaning is required, affecting continuous operation. Additionally, the storage chamber has a limited capacity, requiring frequent discharge when treating large volumes of wastewater, impacting treatment efficiency. Utility Model Content

[0005] To address the shortcomings of existing technologies, the sludge filtration system for wastewater treatment plants provided by this utility model optimizes the sludge pretreatment and pressure filtration process through design improvements such as heating and stirring of the treatment tank, pH detection and chemical dosing, and online pressure monitoring. It utilizes the circulation of acid washing liquid and filtrate to achieve resource utilization, and combines automatic shutdown, pressure relief, sewage return and backwashing mechanisms under abnormal operating conditions to ensure safe and stable operation. It also improves treatment efficiency, reduces costs, enhances environmental protection and operational flexibility.

[0006] The sludge filtration system for a wastewater treatment plant according to this utility model includes a sludge conditioning tank. The sludge conditioning tank is connected to a treatment tank via a sludge conveying pump. The treatment tank is connected to the inlet of a plate and frame filter press via a feed pump. A filtrate discharge valve is provided at the filtrate outlet at the bottom of the plate and frame filter press. A filter is connected after the filtrate discharge valve. Pipelines connecting the filter outlet to the filtrate tank and the acid washing liquid storage tank are respectively provided. The filtrate tank is provided with a return pipeline connected to the backwash water inlet of the plate and frame filter press.

[0007] Preferably, the treatment tank is equipped with a dosing pipeline and a pH detection device at the top. The treatment tank adopts a double-jacketed structure, which is used for the introduction and discharge of heating media (such as hot water, steam, heat transfer oil, etc.) to achieve heating treatment of the sludge in the treatment tank and ensure the viscosity of the sludge. A stirring device is installed at the center of the top of the treatment tank to stir the sludge slurry in the treatment tank, prevent it from accumulating at the bottom, and ensure the stability of subsequent pressure filtration.

[0008] Preferably, an online pressure detection device is installed on the pipeline connecting the feed pump and the feed inlet of the plate and frame filter press. The online pressure detection device and the feed pump can form a control loop, and the feed pump will automatically stop when an abnormal pressure occurs.

[0009] Preferably, the bottom of the plate and frame filter press is connected to the storage silo via a pipeline, and a drain valve is installed on the pipeline. The storage silo is connected to the treatment tank via a return pump, which is used to return the sludge in the storage silo for reprocessing. Furthermore, the drain valve and the filtrate discharge valve are kept open and closed respectively during the operation of the device.

[0010] Preferably, the pickling solution storage tank is equipped with a level gauge, and the top is connected to the acid inlet pipeline.

[0011] Preferably, the bottom of the pickling solution storage tank is connected to the cleaning pump, the outlet pipeline of the cleaning pump is connected in parallel to the return pipeline of the filtrate tank, and a three-way valve is provided at the connection of the pipelines.

[0012] Preferably, the backwash water inlet and the feed inlet of the plate and frame filter press are located on opposite side walls of the plate and frame filter press, that is, the sludge feeding direction is opposite to the backwash water feeding direction.

[0013] Specifically, the sludge filtration system of the wastewater treatment plant operates as follows: When the sludge filtration system is in operation, the sludge first enters a sludge conditioning tank for temporary storage. The sludge conditioning tank is open, allowing for sampling and testing of relevant indicators based on actual conditions, and determining subsequent chemical dosages based on the results. The sludge is then transported to a treatment tank via a sludge transfer pump. In the treatment tank, chemicals are added through a top dosing pipeline. A pH monitoring device monitors and controls the acidity and alkalinity during the process in real time to prevent the filtrate from exceeding standards and wasting resources. A heating medium is introduced through a double-layer jacket structure to adjust the sludge temperature and reduce viscosity. A top stirring device continuously stirs the sludge to prevent it from accumulating at the bottom. The treated sludge is then pumped to the inlet of a plate and frame filter press via a pipeline equipped with an online pressure monitoring device. The plate and frame filter press performs filtration. The filtrate from the bottom outlet flows into the filter through a filtrate discharge valve. During normal operation, the filtrate from the filter outlet is transported to a filtrate tank. The filter removes trace impurities from the filtrate, ensuring that the filtrate can be reused in subsequent processes after returning to the filtrate tank.

[0014] After the plate and frame filter press finishes its work, the sludge is discharged, and subsequent filter press operations continue. After multiple cycles of filter press, in order to ensure that the filtrate channels and filter cloth pores in the plate and frame are not blocked and affect subsequent filter press operations, the plate and frame filter press needs to be cleaned with pickling solution. The pickling solution in the pickling solution storage tank enters the backwash water inlet of the plate and frame filter press through the cleaning pump and three-way valve to wash the plate and frame filter press countercurrently. The filtrate after washing is filtered by the filter and then returned to the pickling solution storage tank to continue to participate in the preparation of pickling solution.

[0015] During operation, the filter cloth of the plate and frame filter press is prone to clogging due to factors such as sludge viscosity. Direct unloading at this time can easily lead to a series of safety problems. Therefore, when the system malfunctions (the online pressure detection device at the plate and frame filter press inlet is abnormal and there is no filtrate at the outlet), firstly, shut down the feed pump to ensure the equipment is stopped, release the residual pressure in the filter chamber (to avoid safety hazards caused by pressurized operation), open the drain valve at the bottom of the plate and frame filter press, and close the filtrate discharge valve to prevent slurry from mixing with subsequent equipment. Discharge the high-concentration slurry accumulated in the filter chamber to the storage silo and circulate it to the treatment tank for further processing. Secondly, open the backwash water inlet of the plate and frame filter press, add filtrate or acid wash water to the plate and frame filter press, and continuously flush for 5-15 minutes, observing the turbidity of the liquid backwashed from the drain valve until the liquid is clear. Finally, continue subsequent operations according to the secondary treatment status of the slurry in the treatment tank.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows: The double-layer jacketed heating structure of the treatment tank of this utility model can adjust the sludge temperature, reduce viscosity, improve sludge fluidity and dewatering performance, and enhance filtration efficiency; the stirring device prevents sludge deposition, ensures slurry uniformity, avoids uneven filtration caused by excessively high local concentrations, and extends the filtration cycle; the pH detection and dosing system are linked to accurately control the dosage of chemicals and reduce chemical waste; secondly, the online pressure detection device monitors the feed pressure in real time, promptly detects abnormalities such as filter cloth blockage, avoids equipment overload operation, and ensures the continuity of the filtration process; the drain valve and filtrate discharge valve, together with the backwashing device and filter, can effectively remove impurities in the filter cloth pores, restore filter cloth permeability, reduce the cost of frequent replacement due to filter cloth blockage, and ensure operational stability and safety. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the sludge filtration system for the wastewater treatment plant described in this utility model.

[0018] In the diagram: 1. Sludge conditioning tank; 2. Sludge transfer pump; 3. Treatment tank; 4. Feed pump; 5. Online pressure monitoring device; 6. Plate and frame filter press; 7. Filtrate discharge valve; 8. Sewage discharge valve; 9. Filter; 10. Pickling solution storage tank; 11. Filtrate pool; 12. Cleaning pump; 13. Three-way valve; 14. Storage silo; 15. Level gauge; 16. Acid feed pipeline; 17. Return pump; 18. pH monitoring device; 19. Chemical dosing pipeline. Detailed Implementation

[0019] The specific technical solution of this utility model will be further described below with reference to the accompanying drawings.

[0020] like Figure 1 As shown, the sludge filtration system of the wastewater treatment plant includes a sludge conditioning tank 1, a plate and frame filter press 6, and an acid washing liquid storage tank 10. The sludge conditioning tank 1 is connected to the treatment tank 3 via a sludge transfer pump 2. The treatment tank 3 is connected to the inlet of the plate and frame filter press 6 via a feed pump 4. A filter 9 is connected to the filtrate outlet at the bottom of the plate and frame filter press 6, and a filtrate discharge valve 7 is installed upstream of the filter 9. The outlet of the filter 9 is respectively provided with pipelines connected to the filtrate tank 11 and the acid washing liquid storage tank 10. The filtrate tank 11 is provided with a return pipeline connected to the backwash water inlet of the plate and frame filter press 6.

[0021] The treatment tank 3 is equipped with a dosing pipeline 19 and a pH detection device 18 at the top. The treatment tank 3 adopts a double-layer jacket structure, and a stirring device is installed at the center of the top.

[0022] An online pressure detection device 5 is installed on the pipeline connecting the feed pump 4 to the feed inlet of the plate and frame filter press 6; the bottom of the plate and frame filter press 6 is connected to the storage silo 14 through a pipeline, and a drain valve 8 is installed on the pipeline; the storage silo 14 is connected to the processing tank 3 through a return pump 17.

[0023] The pickling solution storage tank 10 is equipped with a level gauge 15, and its top is connected to the acid feed pipeline 16; the bottom of the pickling solution storage tank 10 is connected to the cleaning pump 12, the outlet pipeline of the cleaning pump 12 is connected in parallel with the return pipeline of the filter tank 11, and a three-way valve 13 is provided at the pipeline connection.

[0024] The backwash water inlet and the feed inlet of the plate and frame filter press 6 are located on opposite side walls of the plate and frame filter press 6.

[0025] The sludge filtration system of the wastewater treatment plant operates as follows: When the sludge filtration system is in operation, the sludge first enters the sludge conditioning tank 1 for temporary storage. The sludge conditioning tank 1 is open, allowing for sampling and testing of relevant indicators as needed, and determining subsequent chemical dosages based on the results. The sludge is then transported to the treatment tank 3 via the sludge transfer pump 2. In the treatment tank 3, chemicals are added through the top dosing pipeline 19. The pH detection device 18 monitors and controls the acidity and alkalinity in real time to prevent the filtrate from exceeding standards and to avoid resource waste. The double-layer jacket structure allows for... A heating medium is introduced to adjust the sludge temperature and reduce its viscosity. The top stirring device continuously stirs the sludge to prevent it from accumulating at the bottom. The treated sludge is then fed by the feed pump 4 through a pipeline equipped with an online pressure detection device 5 to the inlet of the plate and frame filter press 6. The plate and frame filter press 6 performs the filtration operation. The filtrate from the bottom filtrate outlet flows into the filter 9 through the filtrate discharge valve 7. In normal operation, the filtrate from the outlet of the filter 9 is transported to the filtrate tank 11. The filter 9 can filter out trace impurities in the filtrate, ensuring that the filtrate can be reused in subsequent processes after returning to the filtrate tank 11.

[0026] After the plate and frame filter press 6 finishes working, the sludge is discharged and the subsequent filter press operation continues. After multiple cycles of filter press, in order to ensure that the filtrate channel and filter cloth pores in the plate and frame are not blocked and affect the subsequent filter press, the plate and frame filter press 6 needs to be cleaned with pickling solution. The pickling solution in the pickling solution storage tank 10 enters the backwash water inlet of the plate and frame filter press 6 through the cleaning pump 12 and the three-way valve 13 to wash the plate and frame filter press 6 countercurrently. The filtrate after washing is filtered by the filter 9 and then returned to the pickling solution storage tank 10 to continue to participate in the preparation of pickling solution.

[0027] During operation, the filter cloth of the plate and frame filter press 6 is prone to clogging due to factors such as sludge viscosity. Direct unloading at this time could easily lead to a series of safety issues. Therefore, when the system malfunctions (the online pressure detection device 5 at the inlet of the plate and frame filter press 6 has abnormal pressure and there is no filtrate at the outlet), firstly, shut down the feed pump 4 to ensure the equipment is stopped, release the residual pressure in the filter chamber (to avoid safety hazards caused by pressurized operation), open the drain valve 8 at the bottom of the plate and frame filter press 6, and close the filtrate discharge valve 7 to prevent the slurry from mixing with subsequent equipment. Discharge the high-concentration slurry accumulated in the filter chamber to the storage silo 14 and circulate it to the treatment tank 3 for further processing. Secondly, open the backwash water inlet of the plate and frame filter press 6, and connect the filtrate or acid wash water to the plate and frame filter press 6, continuously flushing for 5-15 minutes, observing the turbidity of the liquid backwashed from the drain valve 8 until the liquid is clear. Finally, continue subsequent operations according to the secondary treatment status of the slurry in the treatment tank 3.

Claims

1. A sludge filtration system for a wastewater treatment plant, characterized in that, The system includes a sludge conditioning tank (1), a plate and frame filter press (6), and an acid washing liquid storage tank (10). The sludge conditioning tank (1) is connected to the treatment tank (3) via a sludge transfer pump (2). The treatment tank (3) is connected to the feed inlet of the plate and frame filter press (6) via a feed pump (4). A filter (9) is connected to the filtrate outlet at the bottom of the plate and frame filter press (6). The outlet of the filter (9) is respectively provided with pipelines connected to the filtrate tank (11) and the acid washing liquid storage tank (10). The filtrate tank (11) is provided with a return pipeline connected to the backwash water inlet of the plate and frame filter press (6).

2. The sludge filtration system for a wastewater treatment plant according to claim 1, characterized in that, The treatment tank (3) is equipped with a dosing pipeline (19) and a pH detection device (18) on the top. The treatment tank (3) adopts a double-layer jacket structure and a stirring device is installed at the center of the top.

3. The sludge filtration system for a wastewater treatment plant according to claim 1, characterized in that, An online pressure detection device (5) is installed on the pipeline connecting the feed pump (4) and the feed inlet of the plate and frame filter press (6).

4. The sludge filtration system for a wastewater treatment plant according to claim 1, characterized in that, The bottom of the plate and frame filter press (6) is connected to the storage silo (14) via a pipeline, and a drain valve (8) is installed on the pipeline.

5. The sludge filtration system for a wastewater treatment plant according to claim 4, characterized in that, The storage silo (14) is connected to the processing tank (3) via a reflux pump (17).

6. The sludge filtration system for a wastewater treatment plant according to claim 1, characterized in that, The pickling solution storage tank (10) is equipped with a level gauge (15), and the top is connected to the acid inlet pipeline (16).

7. The sludge filtration system for a wastewater treatment plant according to claim 1, characterized in that, The bottom of the pickling solution storage tank (10) is connected to the cleaning pump (12), and the outlet pipe of the cleaning pump (12) is connected in parallel with the return pipe of the filter tank (11). A three-way valve (13) is installed at the connection of the pipes.

8. The sludge filtration system for a wastewater treatment plant according to claim 1, characterized in that, The backwash water inlet and the feed inlet of the plate and frame filter press (6) are located on opposite side walls of the plate and frame filter press (6).

9. The sludge filtration system for a wastewater treatment plant according to claim 1, characterized in that, The plate and frame filter press (6) is equipped with a filtrate discharge valve (7) at the filtrate outlet.

Images