Activated sludge dewatering device

Abstract

The utility model discloses an activated sludge dewatering device which comprises a cyclone separator, an ejector, an air compressor, a laminated spiral sludge dewatering machine and a waste water tank, the laminated spiral sludge dewatering machine is fixed to the top of the waste water tank, and a drainage pipe on the lower side of the laminated spiral sludge dewatering machine is communicated with the waste water tank; a liquid outlet of the flocculation cylinder is communicated with a feeding hole of the laminated spiral sludge dewatering machine; the top of the cyclone separator is provided with a sludge inlet and an overflow port communicated with the wastewater tank, the bottom of the cyclone separator is provided with an underflow port, an exhaust port of the air compressor is communicated with an air inlet of the ejector, an ejection port of the ejector is communicated with a liquid inlet pipe of the flocculation cylinder, and two negative pressure ports of the ejector are respectively communicated with the underflow port of the cyclone separator and the medicament tank. The cyclone separator and the laminated spiral sludge dewatering machine are combined for use, fine sand is continuously removed, activated sludge is recycled, and the problems of pipeline silting, aeration equipment abrasion, sludge dewatering equipment abrasion and the like caused by the fine sand are solved.

Description

Technical Field

[0001] This utility model relates to a dewatering device for activated sludge. Background Technology

[0002] To meet nitrogen and phosphorus removal requirements, some waterless treatment facilities have eliminated primary sedimentation tanks, resulting in a large amount of sludge with a particle size of less than 0.2 mm entering the biological treatment unit along with the activated sludge. This leads to a high content of sludge in the suspended solids, which can cause problems such as pipe blockage in subsequent wastewater treatment facilities, wear and tear on aeration equipment, and wear and tear on sludge dewatering equipment. Therefore, it is necessary to remove the sludge from the activated sludge. Currently, hydrocyclones are commonly used for pretreatment of activated sludge to remove the sludge. However, hydrocyclones can only remove heavier sludge and cannot effectively remove lighter sludge. Therefore, the removal of sludge from activated sludge remains a problem that needs to be addressed. Utility Model Content

[0003] To address the problems of siltation in sewage treatment facilities, wear and tear on aeration equipment, and wear and tear on sludge dewatering equipment caused by silt in existing technologies, this application proposes an activated sludge dewatering device, which includes a hydrocyclone separator, an ejector, an air compressor, a disc spiral sludge dewatering machine, and a wastewater tank. The disc spiral sludge dewatering machine is fixedly installed on the top of the wastewater tank, and the drain pipe on the lower side of the disc spiral sludge dewatering machine is connected to the wastewater tank. The liquid outlet of the flocculation cylinder is connected to the feed inlet of the disc spiral sludge dewatering machine.

[0004] The cyclone separator has a sludge inlet and an overflow outlet at the top, and a bottom outlet at the bottom. The exhaust port of the air compressor is connected to the air inlet of the ejector, and the ejector's nozzle is connected to the liquid inlet pipe of the flocculation cylinder. The ejector has two negative pressure ports, one of which is connected to the bottom outlet of the cyclone separator, and the other is connected to the reagent tank. The overflow outlet is connected to the wastewater tank.

[0005] When this application is in operation, activated sludge is pumped tangentially into a hydrocyclone separator via a sludge inlet using a sludge pump. After centrifugal separation, the supernatant is discharged from the overflow port and enters a wastewater tank. Compressed air generated by an air compressor enters the ejector through the air inlet, creating negative pressure. Under this negative pressure, the flocculant in the reagent tank enters the ejector through a connected negative pressure port. Simultaneously, the sludge mixture containing fine sand discharged from the underflow port also enters the ejector through another negative pressure port and mixes with the flocculant to form a flocculated mixture. The flocculated mixture enters the flocculation cylinder. The flocculated mixture containing a large amount of flocculents enters a disc spiral sludge dewatering machine through the feed inlet for concentration. The resulting dry material after concentration is discharged through the discharge port of the disc spiral sludge dewatering machine. The filtrate discharged from the drain pipe of the disc spiral sludge dewatering machine enters the wastewater tank and mixes with the supernatant discharged from the hydrocyclone separator before being returned to the biological treatment unit as activated sludge for reuse.

[0006] This application utilizes a combination of a hydrocyclone separator and a disc spiral sludge dewatering machine to continuously remove fine sand from activated sludge and recycle the activated sludge, reducing its consumption and ensuring the normal operation of subsequent biological treatment units. Because the fine sand is removed from the activated sludge, problems such as pipe blockage, aeration equipment wear, and sludge dewatering equipment wear caused by fine sand are effectively avoided.

[0007] Specifically, the ejector includes a vacuum cylinder, a nozzle inserted into the vacuum cylinder from one end along the axis of the vacuum cylinder, a mixing chamber connected to the other end of the vacuum cylinder, an air inlet for the ejector at the end of the nozzle located outside the vacuum cylinder, two negative pressure ports formed on the side wall of the vacuum cylinder, the mixing chamber being conical, the larger end of the mixing chamber being connected to the vacuum cylinder, and the smaller end of the mixing chamber forming the ejection port.

[0008] When the above-described injector is in use, compressed air enters through the injector's air inlet and is ejected from the nozzle, creating a negative pressure inside the vacuum cylinder. This negative pressure draws the flocculant from the reagent tank into the vacuum cylinder, eliminating the need for a water pump to add the flocculant. The injector also mixes the flocculant and activated sludge, improving the uniformity of flocculant distribution in the activated sludge.

[0009] Furthermore, to avoid interference between the two negative pressure ports, the two negative pressure ports are set symmetrically.

[0010] Specifically, the flocculation cylinder includes a vertically extending, cylindrical body and a conical bottom at the lower end of the body. A liquid inlet pipe is located at the upper part of the flocculation cylinder, and a liquid outlet is located at the bottom of the conical bottom. The conical bottom allows all material in the flocculation cylinder to be discharged and enter the disc spiral sludge dewatering machine, preventing the formation of deposits such as flocs or fine sand at the bottom of the flocculation cylinder.

[0011] Furthermore, the liquid inlet pipe is positioned tangentially to the cylinder body. This design allows the material entering the flocculation cylinder to form a vortex-like fluid and gradually descend to the bottom of the flocculation cylinder, avoiding damage to the formed flocs caused by agitators.

[0012] Furthermore, to facilitate the transport of dry sludge, a conveyor is installed below the sludge discharge port of the disc spiral sludge dewatering machine, allowing the sludge discharged from the discharge port to fall onto the conveyor. Attached Figure Description

[0013] Figure 1 This is a structural schematic diagram of an embodiment of the present invention.

[0014] Figure 2 This is a schematic diagram of the injector.

[0015] Figure 3 This is a schematic diagram of the flocculation cylinder.

[0016] Figure 4 yes Figure 3 A view from the center AA direction. Detailed Implementation

[0017] See Figures 1-4 A dewatering device for activated sludge includes a hydrocyclone separator 10, an ejector 20, an air compressor 24, a disc spiral sludge dewatering machine 50, and a wastewater tank 60. The disc spiral sludge dewatering machine 50 is fixedly installed on the top of the wastewater tank 60. The drain pipe 52 on the lower side of the disc spiral sludge dewatering machine is connected to the wastewater tank. The feed inlet 51 of the disc spiral sludge dewatering machine is connected to the liquid outlet 42 of the flocculation cylinder 40.

[0018] In this embodiment, the flocculation cylinder 40 includes a cylindrical body 44 extending vertically and in a cylindrical shape, and a conical bottom 43 disposed at the lower end of the cylindrical body 44. A liquid inlet pipe 41 is disposed at the upper part of the cylindrical body, and a liquid outlet 42 is disposed at the bottom of the conical bottom. The liquid inlet pipe 41 is welded to the cylindrical body 44 along the tangential direction of the cylindrical body 44.

[0019] The ejector 20 is a Venturi ejector, specifically comprising a vacuum cylinder 201, a nozzle 21 inserted into the vacuum cylinder from one end along its axis, a mixing chamber 23 connected to the other end of the vacuum cylinder 201, and an air inlet 211 formed by the nozzle located outside the vacuum cylinder. A straight pipe section 212 is provided at the end of the nozzle that enters the vacuum cylinder. Two negative pressure ports 22 are formed on the side wall of the vacuum cylinder, and the two negative pressure ports are symmetrically arranged. The mixing chamber 23 is conical, with its larger end connected to the vacuum cylinder and its smaller end forming an ejection port 231.

[0020] A mud inlet 11 and an overflow outlet 12 are provided at the top of the hydrocyclone 10, and an underflow outlet 13 is provided at the bottom of the hydrocyclone 10. The hydrocyclone 10 is an existing mature technology and will not be described in detail.

[0021] The exhaust port of the air compressor 24 is connected to the air inlet 211 of the injector via the air compressor pipe 25. The injection port 231 of the injector is connected to the liquid inlet pipe 41 of the flocculation cylinder 40 via the injection pipe 27. Of the two negative pressure ports, one negative pressure port is connected to the underflow port 13 of the cyclone separator 10, and the other negative pressure port is connected to the reagent outlet 32 ​​of the reagent tank 30. To maintain the uniformity of the reagent in the reagent tank, a stirrer 31 is installed on the reagent tank.

[0022] The overflow port 12 of the hydrocyclone separator 10 is connected to the wastewater tank via the overflow pipe 15.

[0023] To facilitate sludge transport, a conveyor 70 is installed below the sludge discharge port 53 of the disc spiral sludge dewatering machine, allowing the sludge discharged from the discharge port to fall onto the conveyor.

[0024] When this embodiment is running, activated sludge 14 is pumped tangentially into the hydrocyclone separator via the sludge inlet 11 using a sludge pump. After centrifugal separation, the supernatant is discharged from the overflow outlet 12 and enters the wastewater tank via the overflow pipe 15. Compressed air generated by the air compressor enters the ejector through the air inlet 211, generating negative pressure. Under the action of negative pressure, the flocculant in the reagent tank 30 enters the vacuum cylinder through the connected negative pressure port. At the same time, the sludge mixture containing fine sand is discharged from the bottom outlet. The mixture enters the vacuum cylinder through another negative pressure port and mixes with the flocculant in the mixing chamber to form a flocculated mixture. The flocculated mixture enters the flocculation cylinder tangentially through the liquid inlet pipe 41 and forms a swirling flow. The flocculated mixture containing a large amount of flocculents enters the stacked spiral sludge dewatering machine through the feed inlet 51 for concentration. After concentration, the resulting dry material is discharged through the sludge discharge port 53 and falls onto the conveyor belt 70, which is then transported to the drying plant for further processing.

[0025] The filtrate discharged from the drain pipe 52 of the disc spiral sludge dewatering machine enters the wastewater tank 60 and mixes with the supernatant discharged from the hydrocyclone separator before returning to the biochemical treatment unit as activated sludge for reuse.

Claims

1. A dewatering device for activated sludge, characterized in that, It includes a hydrocyclone separator, an ejector, an air compressor, a disc spiral sludge dewatering machine, and a wastewater tank. The disc spiral sludge dewatering machine is fixedly installed on the top of the wastewater tank. The drain pipe on the lower side of the disc spiral sludge dewatering machine is connected to the wastewater tank, and the liquid outlet of the flocculation cylinder is connected to the feed inlet of the disc spiral sludge dewatering machine. The cyclone separator has a sludge inlet and an overflow outlet at the top, and a bottom outlet at the bottom. The exhaust port of the air compressor is connected to the air inlet of the ejector, and the ejector's nozzle is connected to the liquid inlet pipe of the flocculation cylinder. The ejector has two negative pressure ports, one of which is connected to the bottom outlet of the cyclone separator, and the other is connected to the reagent tank. The overflow outlet is connected to the wastewater tank.

2. The dehydration device according to claim 1, characterized in that, The ejector includes a vacuum cylinder, a nozzle inserted into the vacuum cylinder from one end along the axis of the vacuum cylinder, a mixing chamber connected to the other end of the vacuum cylinder, an air inlet for the ejector formed at the end of the nozzle located outside the vacuum cylinder, two negative pressure ports formed on the side wall of the vacuum cylinder, a conical mixing chamber connected to the vacuum cylinder at its larger end, and an ejection port formed at its smaller end.

3. The dehydration device according to claim 2, characterized in that, The two negative pressure ports are set symmetrically.

4. The dehydration device according to claim 1, characterized in that, The flocculation cylinder includes a cylindrical body extending vertically and having a conical bottom at the lower end of the cylindrical body. The liquid inlet pipe is located at the upper part of the flocculation cylinder, and the liquid outlet is located at the bottom of the conical bottom.

5. The dehydration device according to claim 4, characterized in that, The liquid inlet pipe is installed on the cylinder along the tangential direction of the cylinder.

6. The dehydration device according to claim 1, characterized in that, A conveyor is installed below the sludge discharge port of the disc spiral sludge dewatering machine, allowing the sludge discharged from the discharge port to fall onto the conveyor.

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