Activated sludge solid-liquid separation device and separation system

Abstract

The invention discloses an activated sludge solid-liquid separation device and separation system, and relates to the technical field of sewage treatment, the activated sludge solid-liquid separation device comprises a drain pipe, a filter disc and a flushing assembly; the drainage pipe is used for being arranged below the liquid level of activated sludge and is close to the liquid level of the activated sludge, the first end of the drainage pipe is in transmission connection with the motor, the filtering disc is installed on the drainage pipe, the axis of the filtering disc is parallel to the axis of the drainage pipe, a containing cavity is formed in the filtering disc, and water filtering holes communicated with the containing cavity are formed in the filtering disc. The accommodating cavity is communicated with the drain pipe, the flushing assembly is arranged above the liquid level of the activated sludge, the flushing assembly can clean the sludge deposited on the surface of the filter disc, the permeability of the filter disc is ensured, the device can operate continuously and stably, and the cleaning mode reduces the operating power of the flushing equipment.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to an activated sludge solid-liquid separation device and separation system. Background Technology

[0002] In the field of wastewater treatment, the sludge-water mixture after biological treatment requires efficient solid-liquid separation to obtain clear treated effluent. Membrane bioreactor (MBR) technology, as an advanced solution, has been widely used. This technology replaces traditional secondary sedimentation tanks by integrating microfiltration or ultrafiltration membrane modules, offering significant advantages such as high effluent quality, small footprint, and high sludge concentration.

[0003] However, a core problem that is unavoidable during the long-term operation of MBR technology is membrane fouling. During the filtration process, suspended solids, colloidal substances, dissolved organic matter, and microbial metabolites in the activated sludge mixture continuously deposit on the membrane surface, forming a filter cake layer, or directly adsorbing and clogging the micropores of the membrane module. This fouling leads to a sharp increase in membrane filtration resistance and a decrease in membrane flux, thus requiring frequent physical or chemical interventions to restore membrane performance, severely restricting the high efficiency and economical operation of this technology.

[0004] If a dedicated permeate pump is used to drive the filtration process, supplemented by high-volume, high-intensity aeration, the membrane surface can be flushed by a gas-liquid two-phase flow to slow down contaminant deposition. While this method can alleviate contamination to some extent, it consumes a huge amount of energy. Regular chemical cleaning not only increases the cost of chemicals and labor, but chemical residues inevitably shorten the lifespan of the membrane material, leading to premature replacement of expensive membrane modules and further increasing the overall system maintenance costs.

[0005] Therefore, there is an urgent need for an activated sludge solid-liquid separation device and system that has low operation and maintenance costs and can operate continuously and stably. Summary of the Invention

[0006] The purpose of this invention is to provide an activated sludge solid-liquid separation device and system to solve the problems existing in the prior art. The rotating drain pipe can rotate the filter disc to above the liquid surface of the activated sludge, and the flushing component set above the liquid surface of the activated sludge can flush the deposited sludge, thereby reducing operation and maintenance costs while ensuring continuous and stable operation of the device.

[0007] To achieve the above objectives, the present invention provides the following solution: This invention provides an activated sludge solid-liquid separation device and separation system, comprising: A drain pipe is provided below the liquid surface of the activated sludge. The drain pipe is positioned close to the liquid surface of the activated sludge. The first end of the drain pipe is connected to a motor drive, and the second end of the drain pipe is connected to the clean water zone. A filter disc is installed on the drain pipe, the axis of the filter disc is parallel to the axis of the drain pipe, the filter disc has a receiving cavity inside, and the filter disc has filter holes that communicate with the receiving cavity. The receiving cavity is connected to the drain pipe. The filter includes a flushing assembly positioned above the surface of the activated sludge and capable of cleaning sludge deposited on the surface of the filter disc.

[0008] In one embodiment, at least two filter discs are provided, and the rinsing components are provided on both axial sides of the filter discs.

[0009] In one embodiment, the flushing assembly includes a main pipe, branch pipes, and flushing nozzles. The main pipe is used to connect to the water supply tank. The branch pipes are provided on both sides of the filter disc along its axial direction. The flushing nozzles are installed on the branch pipes. Any branch pipe is connected to the main pipe.

[0010] In one embodiment, the branch pipe is vertically arranged, and the axis of the branch pipe and the drain pipe are located in the same plane. Along the axial direction of the branch pipe, a plurality of flushing nozzles are provided on the branch pipe.

[0011] As one embodiment, along the top-to-bottom direction, the angle between the water outlet direction of the plurality of flushing nozzles and the extension direction of the branch pipe gradually increases, and the angle between the water outlet direction of the lowest flushing nozzle and the extension direction of the branch pipe is 90 degrees.

[0012] In one embodiment, the main pipe is connected to the water supply tank via a first water pump.

[0013] In one embodiment, the filter disc is coaxially arranged with the drain pipe.

[0014] The present invention also discloses a separation system, comprising: A filtration tank, which is connected to a biological treatment tank; And the aforementioned activated sludge solid-liquid separation device, wherein the activated sludge solid-liquid separation device is installed in the filtration tank.

[0015] In one embodiment, the filtration tank includes a filtration zone and a clear water zone. The activated sludge solid-liquid separation device is installed in the filtration zone. The second end of the drain pipe is connected to the clear water zone. The filtration zone is connected to the rear end of the biological tank via a second water pump.

[0016] As one embodiment, the filtration zone is provided with an overflow port, which is connected to the front end of the biochemical tank.

[0017] The present invention achieves the following technical effects compared to the prior art: In the activated sludge solid-liquid separation device and system disclosed in this invention, a rotatable drain pipe is positioned below the liquid surface of the activated sludge. By rotating the drain pipe, the filter disc mounted on the drain pipe can be flipped to the surface of the activated sludge. As filtration proceeds, a layer of sludge will be deposited on the surface of the filter disc. When the deposited sludge rotates to the surface of the activated sludge, it can be cleaned off the surface of the filter disc by a flushing component positioned above the liquid surface of the activated sludge, ensuring the permeability of the filter disc and facilitating continuous and stable operation of the device. Furthermore, this method of cleaning the deposited sludge above the liquid surface of the activated sludge eliminates the influence of activated sludge on the cleaning process, reduces the operating power of the flushing equipment, and ensures continuous and stable operation of the device while reducing maintenance costs. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the activated sludge solid-liquid separation device in an embodiment of the present invention; Figure 2 This is a schematic diagram of the separation system in an embodiment of the present invention.

[0020] The components are as follows: 1. Drainage pipe; 2. Motor; 3. Filter disc; 4. Main pipe; 5. Branch pipe; 6. First water pump; 7. Filter tank; 8. Biochemical tank; 9. Filtering zone; 10. Clear water zone; 11. Second water pump. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] The purpose of this invention is to provide an activated sludge solid-liquid separation device and separation system to solve the problems existing in the prior art. By using a flushing component set above the activated sludge liquid surface, the deposited sludge on the filter disc can be cleaned, reducing operation and maintenance costs while ensuring continuous and stable operation of the device.

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1 Please refer to Figure 1 - Figure 2 This embodiment provides an activated sludge solid-liquid separation device, including: a drain pipe 1, a filter disc 3, and a rinsing assembly. The drain pipe 1 is positioned below the liquid surface of the activated sludge, close to the liquid surface. The first end of the drain pipe 1 is connected to a motor 2, and the second end is connected to a clear water zone 10. The filter disc 3 is mounted on the drain pipe 1, with its axis parallel to the axis of the drain pipe 1. The filter disc 3 has an internal cavity, and filter holes communicating with the cavity are opened on it. The cavity is connected to the drain pipe 1. The rinsing assembly is positioned above the liquid surface of the activated sludge. Its working principle is that the drain pipe 1's proximity to the activated sludge liquid surface ensures that the filter disc 3 remains above the activated sludge liquid surface during the rotation of the drain pipe 1. Under hydrostatic pressure, water in the activated sludge can pass through the filter holes and enter the filter disc 3. Because the drain pipe 1 is below the liquid surface of the activated sludge, therefore... Water in filter disc 3 gradually enters drain pipe 1 under external pressure and flows into clean water zone 10. During this process, impurities in the activated sludge gradually deposit on the surface of filter disc 3, forming deposited sludge, which reduces the permeability of filter disc 3 and affects filtration efficiency. As drain pipe 1 rotates, the deposited sludge is exposed above the surface of activated sludge. This part of the deposited sludge is directly exposed to the air. There is no activated sludge as an obstacle between the flushing component and this exposed part of the deposited sludge. The liquid sprayed by the flushing component can directly flush the filter disc 3 to wash off the deposited sludge on the filter disc 3, eliminating the influence of activated sludge on the flushing process. Therefore, there is no need to use high-power equipment to provide driving force for the flushing component, reducing the operating power of the flushing equipment. After the deposited sludge is flushed, the filter disc 3 is restored to its original permeability, ensuring that the device can continuously and stably perform high-efficiency filtration.

[0025] It is understood that the activated sludge mentioned here refers to a mixture of activated sludge and liquid; the setting of the drain pipe 1 close to the liquid surface of the activated sludge means that the drain pipe 1 is set below the liquid surface of the activated sludge and away from the bottom of the tank containing the activated sludge, so as to ensure that the filter disc 3 can be exposed above the liquid surface of the activated sludge during the rotation of the drain pipe 1.

[0026] In one embodiment, motor 2 is directly connected to drain pipe 1, and motor 2 is directly installed on the side wall of the tank containing activated sludge. Of course, as long as it can be ensured that drain pipe 1 is below the activated sludge liquid level, drain pipe 1 and motor 2 can also be connected indirectly by a transmission component, and motor 2 can also be installed by an independent bracket.

[0027] As one embodiment, in order to improve filtration efficiency, the filter disc 3 is provided with at least two discs.

[0028] Preferably, in order to improve rinsing efficiency, rinsing components are provided on both sides of the filter disc 3 along its axial direction.

[0029] As one embodiment, the flushing assembly includes a main pipe 4, branch pipes 5, and flushing nozzles. The main pipe 4 is used to connect to the water supply tank. Branch pipes 5 are provided on both sides of the filter disc 3 along the axial direction. The flushing nozzles are installed on the branch pipes 5. Any branch pipe 5 is connected to the main pipe 4. In this way, water can be supplied to the flushing nozzles on multiple branch pipes 5 through one main pipe 4 at the same time, which simplifies the pipeline.

[0030] As one embodiment, two sets of flushing nozzles facing different directions can be installed on the same branch pipe 5. That is, one set of flushing nozzles faces the filter disc 3 on the left side of the branch pipe 5, and the other set of nozzles faces the filter disc 3 on the right side of the branch pipe 5. When this arrangement is adopted, only one set of nozzles facing the filter disc 3 is installed on the two outermost branch pipes 5. Taking the left-right direction as an example, only one set of flushing nozzles facing the right filter disc 3 is installed on the branch pipe 5 to the left of the leftmost filter disc 3, and only one set of flushing nozzles facing the left filter disc 3 is installed on the branch pipe 5 to the right of the rightmost filter disc 3.

[0031] As an example, two branch pipes 5 can also be provided between the two filter discs 3, spaced apart along the axial direction of the main pipe 4. The flushing nozzle on the left branch pipe 5 is positioned facing the filter disc 3 on the left, and the flushing nozzle on the right branch pipe 5 is positioned facing the filter disc 3 on the right.

[0032] As an example, the branch pipe 5 is vertically arranged, and the axis of the branch pipe 5 and the drain pipe 1 are located in the same plane. Along the axis of the branch pipe 5, multiple flushing nozzles are provided on the branch pipe 5. By setting the branch pipe 5 in the above form, the area swept by the branch pipe 5 on the surface of the filter disc during the rotation of the filter disc 3 is increased, thereby improving the flushing effect.

[0033] As an example, the angle between the water outlet direction of multiple flushing nozzles and the extension direction of branch pipe 5 gradually increases from top to bottom. The angle between the water outlet direction of the lowest flushing nozzle and the extension direction of branch pipe 5 is 90 degrees. This arrangement of flushing nozzles located at the top and tilted downwards towards the filter disc ensures that the sludge deposited on the surface of the filter disc 3 can be cleaned off while the water flow guides the flushed sludge back into the tank containing activated sludge, avoiding sludge splashing everywhere. Furthermore, the arrangement of the angle gradually increasing from top to bottom reduces the downward impact force that the water flow from the flushing nozzles can provide to the sludge, preventing the flushed sludge from being pushed below the surface of the activated sludge liquid under the action of the water flow, thus preventing the flushed sludge from settling too quickly.

[0034] It is understandable that the extension direction of branch pipe 5 refers to the direction from the end where branch pipe 5 connects to main pipe 4 towards the free end of branch pipe 5.

[0035] As one embodiment, the main pipe 4 is connected to the water supply tank through the first water pump 6, which can provide sufficient water pressure for the flushing nozzles.

[0036] As one embodiment, the filter disc 3 is coaxially arranged with the drain pipe 1, which reduces the overall size of the device along the radial direction of the drain pipe 1.

[0037] Example 2 Please refer to Figure 1 - Figure 2 This embodiment provides a separation system, including a filter tank 7 and the above-mentioned activated sludge solid-liquid separation device. The filter tank 7 is used to connect with the biological treatment tank 8. The activated sludge solid-liquid separation device is installed in the filter tank 7. This separation system can be applied to different biological treatment tanks 8. When in use, it is only necessary to connect the filter tank 7 with the target biological treatment tank 8 to filter the activated sludge.

[0038] As one embodiment, the filter tank 7 includes a filter zone 9 and a clear water zone 10. An activated sludge solid-liquid separation device is installed in the filter zone 9, and the second end of the drain pipe 1 is connected to the clear water zone 10. By setting up the clear water zone 10, the filtered clear water can be collected directly.

[0039] Furthermore, the filtration zone 9 is connected to the rear end of the biological treatment tank 8 via the second water pump 11, so as to extract the activated sludge in the biological treatment tank 8 into the filtration zone 9.

[0040] As an example, the filtration zone 9 is provided with an overflow port, which is connected to the front end of the biological tank 8. Along the top-to-bottom direction, the angle between the water outlet direction of multiple flushing nozzles and the extension direction of the branch pipe 5 gradually increases. The angle between the water outlet direction of the lowest flushing nozzle and the extension direction of the branch pipe 5 is 90 degrees. The arrangement of the angle gradually increasing from top to bottom makes the downward impact force that the water flow sprayed by the flushing nozzles can provide to the sludge gradually decrease, avoiding the sludge being flushed down being pushed below the surface of the activated sludge under the action of the water flow. As the flushed sediment and the water sprayed by the flushing nozzles enter the filtration zone 9, the sludge flushed down from the filter plate falls into the filtration zone 9 and mixes with the water sprayed by the flushing nozzles and the original mixed liquid in the filtration zone 9. The concentration in the tank will gradually increase to a stable value under a certain operating condition. During this process, the total liquid level of the mixed liquid in the filtration zone 9 will rise. When the liquid level of the mixed liquid is higher than the overflow port, it can flow out from the overflow port.

[0041] As one embodiment, the overflow outlet is a height-adjustable triangular weir. By adjusting the height of the triangular weir, the liquid level in the filtration zone 9 can be controlled, that is, the distance between the liquid level of the mixture in the filtration zone 9 and the drain pipe can be adjusted. Different distances result in different filtration heads and effective filtration areas.

[0042] Preferably, the height of the biological tank 8 is lower than the height of the filtration zone 9. In this case, the mixed liquid in the filtration zone 9 can flow out through the overflow port and eventually return to the front end of the biological tank 8.

[0043] Furthermore, a second water pump 11 is installed between the overflow outlet and the biological treatment tank 8. The second water pump 11 can control the speed at which activated sludge in the biological treatment tank 8 enters the filtration zone 9, thereby controlling the return speed of the mixed liquor in the filtration zone 9.

[0044] As one embodiment, the clear water zone 10 serves as a water supply pool for supplying water to the main pipe 4. The main pipe 4 is connected to the clear water zone 10 via a first water pump 6, which is located below the clear water surface in the clear water zone 10.

[0045] As an example, the bottom of the filtration zone 9 is provided with a drain outlet for periodically discharging settled sludge.

[0046] As an example, depending on the different treatment precision, the water discharged from the clear water zone 10 can be directly discharged in compliance with standards, or it can be further treated by a deep treatment unit.

[0047] As one embodiment, the filter disc 3 is a rotary dynamic membrane assembly, which includes a dynamic membrane frame and a filter membrane installed on the frame, with the pore size of the filter membrane serving as the water filtration pore.

[0048] Preferably, the pore size of the filter holes is set to 5~100μm according to different water output requirements.

[0049] As one embodiment, the filter membrane material includes, but is not limited to, polyethylene (PE), polypropylene (PP), nylon (PA), and polyester (PET), with a thickness of 30~200μm, a basis weight of 20~300g / m2, and an air permeability of 30~500L / m2. 2 ·s.

[0050] As one embodiment, the filter disc 3 can adjust its rotation speed according to different water quality and water volume requirements, with a rotation speed range of 1~10 rpm.

[0051] As one embodiment, the concentration of activated sludge separated by the filter disc 3 can be controlled by adjusting the influent and overflow rates within the reactor tank and in the effluent. Preferably, the activated sludge concentration can reach up to 50,000 mg / L.

[0052] As one embodiment, the filter disc 3 has a filtration flux of 0.1 m³ / s depending on the pore size and rotation speed. 3 / m 2 · h to 10m 3 / m 2 Between ·h.

[0053] As one embodiment, the water used to rinse the nozzle is 5% to 8% of the water produced; the water produced refers to the clean water discharged from the drain pipe 1.

[0054] As one embodiment, the top of the drain pipe is located 100-200 mm below the static liquid surface of the activated sludge.

[0055] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. An activated sludge solid-liquid separation apparatus, characterized by comprising: It comprises: a drain pipe (1) arranged below the liquid level of activated sludge, the first end of the drain pipe (1) being connected with a motor (2), and the second end of the drain pipe (1) being arranged to communicate with a clear water zone (10); a filter disc (3) arranged on the drain pipe (1), the axis of the filter disc (3) being parallel to the axis of the drain pipe (1), the filter disc (3) having an accommodating cavity inside, and the filter disc (3) being provided with filter holes communicating with the accommodating cavity; and a flushing assembly arranged above the liquid level of the activated sludge, the flushing assembly being capable of cleaning the sludge deposited on the surface of the filter disc (3).

2. The activated sludge solids-liquid separation device according to claim 1, characterized by The filter disc (3) is provided with at least two, and the flushing assembly is arranged on both axial sides of the filter disc (3).

3. The activated sludge solids-liquid separation device according to claim 2, wherein The flushing assembly comprises a main pipe (4), branch pipes (5) and flushing nozzles, the main pipe (4) being arranged to communicate with a water supply tank, the branch pipes (5) being arranged on both axial sides of the filter disc (3), and the flushing nozzles being arranged on the branch pipes (5), each of the branch pipes (5) communicating with the main pipe (4).

4. The activated sludge solids-liquid separation device according to claim 3, wherein The branch pipes (5) are arranged vertically, the branch pipes (5) being arranged in the same plane as the axis of the drain pipe (1), and a plurality of flushing nozzles are arranged on the branch pipes (5) along the axial direction of the branch pipes (5).

5. The activated sludge solids-liquid separation device of claim 4, wherein, In the direction from top to bottom, the angle between the water outlet direction of the flushing nozzles and the extension direction of the branch pipes (5) gradually increases, and the angle between the water outlet direction of the lowermost flushing nozzle and the extension direction of the branch pipes (5) is 90 degrees.

6. The activated sludge solids-liquid separation device according to claim 3, wherein The main pipe (4) communicates with the water supply tank through a first water pump (6).

7. The activated sludge solids-liquid separation device of claim 1, wherein The filter disc (3) is coaxially arranged with the drain pipe (1).

8. A separation system characterized by, It comprises: a filter tank (7) arranged to communicate with a biochemical tank (8); and the activated sludge solid-liquid separation device according to any one of claims 1-7, which is arranged in the filter tank (7).

9. The separation system of claim 8, wherein, The filter tank (7) comprises a filter zone (9) and a clear water zone (10), the activated sludge solid-liquid separation device being arranged in the filter zone (9), the second end of the drain pipe (1) communicating with the clear water zone (10), and the filter zone (9) communicating with the rear end of the biochemical tank (8) through a second water pump (11).

10. The separation system of claim 9, wherein, The filter zone (9) is provided with an overflow port, and the overflow port communicates with the front end of the biochemical tank (8).

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