Rotary drum sludge thickener

Abstract

The utility model discloses a rotary drum sludge thickener which comprises a shell and a rotary drum filter screen, the rotary drum filter screen is assembled on the shell through a hollow shaft, a filtered water outlet and a concentrated sludge outlet are formed in the bottom of the shell, the concentrated sludge outlet is located under the open end of the rotary drum filter screen, and a backwashing pipe is arranged on the outer side of the top of the rotary drum filter screen. A back-flushing liquid tank is arranged on the inner side of the top of the rotary drum filter screen, the back-flushing liquid tank is located under the back-flushing pipe, a back-flushing liquid outlet is formed in the back-flushing liquid tank, and the back-flushing liquid outlet is close to the closed end of the rotary drum filter screen. The utility model has the obvious effect that the backwashing water and the backwashing sludge are mixed with the original water-containing sludge for re-concentration by guiding the concentration initial section of the filter screen of the rotary drum. Backwash water can be prevented from directly entering concentrated sludge to reduce the concentration effect; and tiny sludge particles which are destroyed and disintegrated by backwashing high-pressure water can be flocculated and clustered again, so that meshes of concentration and dehydration equipment are prevented from being blocked.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of environmental protection, and particularly relates to domestic sewage treatment equipment. BACKGROUND

[0002] After adopting the biological method to treat domestic sewage, a large amount of water-containing sludge will be produced, the water content of the water-containing sludge is usually 99.5%, and the sludge content is about 0.5%. These water-containing sludge needs to be treated by a dewatering device such as a filter press or a centrifuge to achieve the purpose of separating sludge and water. The filter press or the centrifuge has a good solid-liquid separation effect, but the running speed is slow, and the sludge treatment capacity per hour is not high (generally about 40-60 m 3 / h). In addition, the sludge content in the water-containing sludge is very low, and the actual output of the sludge of the dewatering device such as the filter press per hour is very small, which further reduces the treatment efficiency of the water-containing sludge. In order to reduce the water content of the water-containing sludge, the water-containing sludge can be concentrated by a concentration device first, and then input into the subsequent dewatering device, so as to greatly increase the sludge content of the water-containing sludge input into the dewatering device and improve the treatment efficiency of the water-containing sludge.

[0003] The drum-type sludge concentration device has the characteristics of continuous operation, mature technology, adjustable range, and is installed and applied in most sewage treatment plants. The main structure of the drum-type sludge concentration device is shown in Figure 1 , which comprises a shell body (A), a drum barrel (B) with a filter screen, a backwashing mechanism (C), and an inner spiral blade (D). The drum barrel (B) is horizontally installed in the shell body (A), the inner spiral blade (D) is fixed on the inner wall of the drum barrel (B), the drum barrel (B) is horizontally rotatably installed in the shell body (A), the water-containing sludge (after adding flocculant) enters from the closed end of the drum barrel (B) and flows out from the open end, the inner spiral blade (D) is used to push the water-containing sludge in layers, part of the water in the water-containing sludge is filtered and discharged through the drum barrel (B), the sludge (flocculation group) adhered to the inner wall / screen hole of the drum barrel (B) is washed by the backwashing mechanism (C), and then freely falls back into the drum barrel (B) and is discharged together with the concentrated water-containing sludge. The shell body (A) is provided with a sludge port and a filtered water port.

[0004] The backwashing mechanism (C) will spray high-pressure water when backwashing the drum barrel (B). Although the flow of the backwashing high-pressure water is not much compared with the flow of the water-containing sludge, it will undoubtedly reduce the concentration effect of the water-containing sludge if it directly falls into the concentrated liquid. In addition, the backwashing high-pressure water will destroy the shape of the flocculation group, so that the structure of the flocculation group is destroyed and re-disintegrated into small particles, causing the screen hole of the drum barrel (B) and the subsequent dewatering device to be easily blocked. UTILITY MODEL CONTENTS

[0005] In order to avoid the problem that backwashing water and backwashing sludge directly enter concentrated sludge when the backwashing mechanism operates, the utility model provides an equipment for guiding backwashing water and backwashing sludge to return to the initial entering position of the water-containing sludge, and the main technical scheme is as follows:

[0006] A drum sludge thickener, comprising a shell, a drum filter screen, the drum filter screen is cylindrical, the center line of the drum filter screen is horizontally arranged, one end of the drum filter screen is closed, the other end is open, the closed end of the drum filter screen is assembled on the shell through a hollow shaft, the inside of the hollow shaft forms a sludge entering channel, the bottom of the shell is provided with a filtered water outlet and a concentrated sludge outlet, the concentrated sludge outlet is located directly below the open end of the drum filter screen, and a backwashing pipe is arranged on the top outside of the drum filter screen, and the key lies in that:

[0007] A backflushing tank is arranged on the top inside of the drum filter screen and located directly below the backwashing pipe, and a backflushing outlet is arranged on the backflushing tank and close to the closed end of the drum filter screen.

[0008] The backwashing water and backwashing sludge fall into the backflushing tank and return to the closed end of the drum filter screen from the backflushing outlet, mix with the water-containing sludge and re-concentrate, and a small amount of flocculating agent remaining in the backwashing sludge and the water-containing sludge can re-react to generate flocculation groups in the mixing and concentrating process. On the one hand, the backwashing water can be prevented from directly entering the concentrated sludge, and the concentration effect is reduced; on the other hand, the small sludge particles that are destroyed and disintegrated by the backwashing high-pressure water can be re-flocculated into groups, so that the mesh holes of the drum barrel and subsequent dehydration equipment are prevented from being blocked. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 It is a structural schematic view of an existing drum sludge thickening device;

[0010] Figure 2 It is a structural schematic view of the utility model;

[0011] Figure 3 It is an assembly relationship schematic view of the sludge inlet pipe 6, the flow guide elbow pipe 7 and the mixed flow pipe 8. DETAILED DESCRIPTION

[0012] The utility model will be further described below in combination with the embodiments and the drawings.

[0013] As shown in Figure 2 and Figure 3 A drum sludge thickener, comprising a shell 1, a drum filter screen 2, the drum filter screen 2 is cylindrical, the center line of the drum filter screen 2 is horizontally arranged, one end of the drum filter screen 2 is closed, the other end is open, and a spiral discharge piece 9 is fixed to the inner wall of the drum filter screen 2 around the center line.

[0014] The closed end of the drum filter 2 is fixed with a hollow shaft 3, the center line of the hollow shaft 3 coincides with the center line of the drum filter 2, one end of the hollow shaft 3 penetrates through the closed end of the drum filter 2 and communicates with the inside of the drum filter 2, the end face of the penetrating end of the hollow shaft 3 is flush with the inner surface of the closed end of the drum filter 2, the outer peripheral surface of the hollow shaft 3 is mounted on the shell 1 through a bearing, the outer peripheral surface of the hollow shaft 3 is sleeved with a belt pulley, the hollow shaft 3 is driven to rotate through a motor assembly and a transmission assembly, the drum filter 2 and the hollow shaft 3 rotate synchronously, and a sludge inlet channel is formed in the inside of the hollow shaft 3.

[0015] The bottom of the shell 1 is provided with a filtered water outlet 1a and a concentrated sludge outlet 1b, the concentrated sludge outlet 1b is located directly below the open end of the drum filter 2, the filtered water outlet 1a is close to the closed end of the drum filter 2, the bottom of the shell 1 has two hopper-shaped parts, the small opening end of one hopper-shaped part forms the filtered water outlet 1a, and the small opening end of the other hopper-shaped part forms the concentrated sludge outlet 1b; the filtered water outlet 1a and the concentrated sludge outlet 1b are respectively provided with a pipeline connecting flange.

[0016] The top outer side of the drum filter 2 is provided with a backwashing pipe 4, the backwashing pipe 4 is parallel to the center line of the drum filter 2, a plurality of high-pressure flushing nozzles 41 are arranged on the backwashing pipe 4 along the length direction of the backwashing pipe 4, the outlets of the high-pressure flushing nozzles 41 are downward, and the outlets of the high-pressure flushing nozzles 41 are close to the outer wall of the drum filter 2.

[0017] The top inner side of the drum filter 2 is provided with a backwashing liquid tank 5, the backwashing liquid tank 5 is parallel to the center line of the drum filter 2, the backwashing liquid tank 5 extends from the open end to the closed end of the drum filter 2, the backwashing liquid tank 5 is located directly below the backwashing pipe 4, and the tank opening of the backwashing liquid tank 5 is upward. The backwashing liquid tank 5 is provided with a backwashing outlet, and the backwashing outlet is located at the closed end of the drum filter 2.

[0018] When the backwashing pipe 4 operates, high-pressure water is shot downward from the high-pressure flushing nozzles 41, sludge flocculation groups adhered to the inner wall of the drum filter 2 are washed down and fall into the backwashing liquid tank 5, and then fall back to the closed end of the drum filter 2 from the backwashing outlet.

[0019] The bottom surface of the backwashing liquid tank 5 is inclined, the bottom surface of the backwashing liquid tank 5 located at the open end of the drum filter 2 is relatively higher, the bottom surface of the backwashing liquid tank 5 located at the closed end of the drum filter 2 is relatively lower, and the backwashing outlet is arranged on the bottom surface of the backwashing liquid tank 5 so as to backflow.

[0020] A mud inlet pipe 6 is movably inserted into the hollow shaft 3, and the mud inlet pipe 6 passes through the closed end of the drum filter 2 and extends into the interior of the drum filter 2; the extending end of the mud inlet pipe 6 is connected to a diversion elbow 7, and the outlet of the diversion elbow 7 faces downward, and the outlet of the diversion elbow 7 is close to the closed end of the drum filter 2.

[0021] Because the sludge intake of the rotary drum sludge thickener needs to be adjusted based on the sludge storage capacity of the front-end sludge storage tank and the processing capacity of the back-end dehydrator, the flow rate of the water-containing sludge entering the rotary drum sludge thickener varies. When the flow rate of the water-containing sludge entering the rotary drum sludge thickener is high, it will flow directly into the middle section of the rotary drum filter 2. If the rotation speed of the rotary drum filter 2 remains unchanged, the water-containing sludge will not have enough time to be filtered. By adding the downward-facing diversion bend 7, the water-containing sludge can be completely confined to the initial section of the rotary drum filter 2, thereby ensuring that the water-containing sludge has sufficient filtering time.

[0022] A mixing pipe 8 is fixed to the inner side of the closed end of the drum filter 2. The mixing pipe 8 is vertically arranged, and the upper end of the mixing pipe 8 is connected to the backflushing outlet. The lower portion of the mixing pipe 8 accommodates and surrounds the diversion elbow 7. A backflushing liquid return cavity is formed between the outer wall of the diversion elbow 7 and the inner wall of the mixing pipe 8. One end of the backflushing liquid tank 5 is fixed to the upper end of the mixing pipe 8, and the other end of the backflushing liquid tank 5 is fixed to the inner wall of the housing 1.

[0023] Under the action of the mixing pipe 8 , the backwash water and backwash sludge can be mixed more evenly with the water-containing sludge flowing out of the diversion elbow 7 . At the same time, the mixing pipe 8 also has the function of supporting and connecting the backwash liquid tank 5 .

[0024] Beneficial Effects: The rotary drum sludge concentrator of this utility model redirects backwash water and backwash sludge back to the initial concentration stage of the rotary drum filter, where they are mixed with the original water-containing sludge for re-concentration. This prevents backwash water from directly entering the concentrated sludge, which would reduce the concentration effect. It also allows the tiny sludge particles that were broken down by the high-pressure backwash water to re-flocculate, preventing clogging of the meshes of the concentration and dehydration equipment.

[0025] Finally, it should be noted that the above description is only a preferred embodiment of the present invention. Under the guidance of the present invention, ordinary technicians in this field can make various similar expressions without violating the purpose and claims of the present invention. Such changes fall within the scope of protection of the present invention.

Claims

1. A rotary drum sludge concentrator, comprising a housing (1) and a rotary drum filter (2), wherein the rotary drum filter (2) is cylindrical, the center line of the rotary drum filter (2) is arranged horizontally, one end of the rotary drum filter (2) is closed and the other end is open, the closed end of the rotary drum filter (2) is assembled on the housing (1) through a hollow shaft (3), a sludge inlet channel is formed inside the hollow shaft (3), a filtered water outlet (1a) and a concentrated sludge outlet (1b) are provided at the bottom of the housing (1), the concentrated sludge outlet (1b) is located directly below the open end of the rotary drum filter (2), and a backwash pipe (4) is arranged on the outside of the top of the rotary drum filter (2), characterized in that: A backwash liquid tank (5) is arranged on the inner side of the top of the drum filter (2), and the backwash liquid tank (5) is located directly below the backwash pipe (4). A backwash liquid outlet is provided on the backwash liquid tank (5), and the backwash liquid outlet is close to the closed end of the drum filter (2).

2. The rotary drum sludge thickener according to claim 1, characterized in that: The backwash pipe (4) is parallel to the center line of the drum filter (2), and a plurality of high-pressure flushing nozzles (41) are installed on the backwash pipe (4) along its length direction, with the outlets of the high-pressure flushing nozzles (41) facing downwards; The backwash liquid tank (5) is parallel to the center line of the drum filter (2), and the backwash liquid tank (5) extends from the open end to the closed end of the drum filter (2), with the notch of the backwash liquid tank (5) facing upward.

3. The rotary drum sludge thickener according to claim 1, characterized in that: The bottom surface of the backwash liquid tank (5) is arranged to be inclined. The bottom surface of the backwash liquid tank (5) located at the open end of the rotary drum filter (2) is higher, while the bottom surface of the backwash liquid tank (5) located at the closed end of the rotary drum filter (2) is lower. The backwash liquid outlet is arranged at the bottom surface of the backwash liquid tank (5).

4. The rotary drum sludge thickener according to claim 1, 2 or 3, characterized in that: A mud inlet pipe (6) is movably inserted into the hollow shaft (3), and the mud inlet pipe (6) passes through the closed end of the rotary drum filter (2) and extends into the interior of the rotary drum filter (2); The extending end of the mud inlet pipe (6) is connected to a diversion elbow (7), the outlet of the diversion elbow (7) faces downward, and the outlet of the diversion elbow (7) is close to the closed end of the drum filter (2).

5. The rotary drum sludge thickener according to claim 4, characterized in that: A mixing pipe (8) is fixed to the inner side surface of the closed end of the drum filter (2). The mixing pipe (8) is arranged vertically. The upper end of the mixing pipe (8) is connected to the backwash liquid outlet. The lower part of the mixing pipe (8) accommodates and surrounds the diversion bend (7). A backwash liquid return cavity is formed between the outer wall of the diversion bend (7) and the inner wall of the mixing pipe (8).

6. The rotary drum sludge thickener according to claim 5, characterized in that: One end of the backflushing liquid tank (5) is fixed to the upper end of the mixing tube (8), and the other end of the backflushing liquid tank (5) is fixed to the inner wall of the outer shell (1).

7. The rotary drum sludge thickener according to claim 1, 2 or 3, characterized in that: A spiral discharge sheet (9) is fixed on the inner wall of the drum filter (2) around its center line.

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