Front flocculation and sedimentation device for sludge concentration and dehydration

Abstract

The utility model discloses a front flocculation and sedimentation device for sludge concentration and dehydration, which comprises a flocculation and sedimentation tank, a sludge inlet and a sludge outlet are respectively arranged on two opposite tank walls of the flocculation and sedimentation tank, and two vertically arranged partition parts are arranged between the sludge inlet and the sludge outlet. The two partition parts divide the internal area of the flocculation settling box into a mixing area, a flocculation area and a discharge area, and the sludge inlet, the mixing area, the flocculation area, the discharge area and the sludge outlet are communicated in sequence; the cross sectional area of the upper part of the flocculation zone is larger than that of the lower part of the flocculation zone; and the flocculation zone naturally transits from the upper part to the lower part. The flocculation and sedimentation tank has the remarkable effects that the tail section of a mud-water mixture flowing through the baffling channel in the flocculation and sedimentation tank can be accelerated, and flocculent precipitates are prevented from being gathered and accumulated at the tail section of the baffling channel, so that the cleaning period of the flocculation and sedimentation tank is prolonged, and even the effect of avoiding cleaning the flocculation and sedimentation tank can be achieved. And a better guarantee is provided for continuous and stable operation of the sludge thickening and dewatering process.

Description

Technical Field

[0001] The utility model relates to the technical field of environmental protection, in particular to a sewage treatment device. Background Art

[0002] During the treatment of domestic sewage, a large amount of water-containing sludge will be produced. The water-containing sludge needs to be further concentrated and dehydrated to achieve the purpose of solid-liquid separation. The separated liquid phase (water) is returned to the sewage treatment system, and the separated solid phase (sludge) can be transported to the sludge drying plant for incineration or granulation.

[0003] The concentration and dehydration process of aqueous sludge requires the help of flocculants (generally PAM) to be carried out better. The aqueous sludge and flocculants need to be fully stirred and mixed before entering the concentration and dehydration equipment (such as concentrators, filter presses or centrifuges). Therefore, it is necessary to configure a corresponding flocculation and sedimentation device before the sludge concentration and dehydration equipment.

[0004] Early flocculation sedimentation devices used multiple independent flocculation tanks / boxes. The water-containing sludge and flocculant in the flocculation tanks / boxes were fully mixed and then discharged into the thickening equipment. The multiple flocculation tanks / boxes cooperated with each other to ensure the continuous operation of the thickening equipment. This flocculation sedimentation device required the configuration of multiple flocculation tanks / boxes and multiple control valves. The equipment cost was relatively high, and the coordination between the multiple flocculation tanks / boxes was poor. The mud and water flow entering the thickening and dehydration equipment was prone to fluctuations.

[0005] Later, researchers proposed a flocculation sedimentation device that can continuously feed the concentration and dehydration equipment. Its basic structure includes a box (A) with two vertically arranged baffles (B) inside the box (A). The multiple baffles (B) divide the internal area of ​​the box (A) into a reciprocating and continuous baffle channel. The box walls of the box (A) corresponding to the two ends of the baffle channel are respectively provided with an inlet and an outlet, wherein the inlet is close to the bottom of the box (A) and the outlet is close to the top of the box (A). Multiple stirring devices (C) are also arranged in the box (A), such as Figure 1 As shown. This continuous flocculation sedimentation device can continuously feed muddy water into the concentration and dehydration equipment to avoid fluctuations in the flow rate of muddy water into the concentration and dehydration equipment. However, as the muddy sewage flows, it continuously reacts with the flocculant to form large clusters of flocculent precipitation. These flocculent precipitations pass through the end of the baffle channel (corresponding to Figure 1 The liquid is likely to accumulate at the bottom of the box (A), and become thicker, reducing the permeability of the baffle channel. If necessary, the baffle channel needs to be cleaned and unblocked. Utility Model Content

[0006] In order to extend the cleaning cycle of the flocculation sedimentation tank, or to avoid cleaning the flocculation sedimentation tank as much as possible, the utility model provides a mechanism that can accelerate the outflow speed of the end section of the baffle channel. The main technical solutions adopted are as follows:

[0007] A sludge concentration and dehydration pre-flocculation and sedimentation device includes a flocculation and sedimentation tank, wherein two opposing tank walls of the flocculation and sedimentation tank are respectively provided with a mud inlet and a mud outlet, and two vertically arranged partitions are arranged between the mud inlet and the mud outlet. The two partitions divide the internal area of ​​the flocculation and sedimentation tank into a mixing area, a flocculation area, and a discharge area. The key features of the device are:

[0008] The mud inlet is connected to the lower part of the mixing zone, the upper part of the mixing zone is connected to the upper part of the flocculation zone, the lower part of the flocculation zone is connected to the lower part of the discharge zone, and the middle part of the discharge zone is connected to the mud outlet; the mixing zone, the flocculation zone and the discharge zone are connected to form a baffle channel, and the horizontal height of the mud outlet is less than the highest horizontal height of the baffle channel;

[0009] The cross-sectional area of ​​the upper portion of the flocculation zone is larger than the cross-sectional area of ​​the lower portion thereof, and the upper portion of the flocculation zone transitions naturally to the lower portion thereof.

[0010] The mud outlet located in the middle of the discharge area can reduce the mud and water discharge height, making it easier to form a liquid level difference with the mixing area and the flocculation area to speed up the discharge of mud and water; at the same time, the cross-sectional area of ​​the flocculation area gradually shrinks from the upper part to the lower part, which can further accelerate the flow of mud and water (based on the Bernoulli principle) and avoid the accumulation of flocculent precipitation at the end of the deflection channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of a prior art;

[0012] Figure 2 It is a structural diagram of the present utility model. DETAILED DESCRIPTION

[0013] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0014] like Figure 2As shown, a sludge concentration and dehydration pre-flocculation and sedimentation device includes a flocculation and sedimentation box 1, which is a cubic box body welded from stainless steel plates. A mud inlet 1a and a mud outlet 1b are respectively provided on two opposite box walls of the flocculation and sedimentation box 1. Two vertically arranged partitions 2 are arranged between the mud inlet 1a and the mud outlet 1b. The two partitions 2 divide the internal area of ​​the flocculation and sedimentation box 1 into a mixing zone 1c, a flocculation zone 1d and a discharge zone 1e. The mixing zone 1c, the flocculation zone 1d and the discharge zone 1e are connected in sequence to form a baffle channel. The baffle channel is specifically connected in the following manner: the mud inlet 1a is connected to the lower part of the mixing zone 1c, the upper part of the mixing zone 1c is connected to the upper part of the flocculation zone 1d through an upper baffle, the lower part of the flocculation zone 1d is connected to the lower part of the discharge zone 1e through a lower baffle, and the middle part of the discharge zone 1e is connected to the mud outlet 1b. The mud outlet 1b is positioned at a lower level than the highest level of the baffle channel. Specifically, the mud outlet 1b is positioned between the upper and lower baffles. This creates a level difference between the liquid levels in the mixing zone 1c and flocculation zone 1d and the mud outlet 1b, accelerating the flow rate at the final section of the baffle channel.

[0015] The cross-sectional area of ​​the upper portion of the flocculation zone 1d is larger than that of the lower portion, resulting in a natural transition from the upper portion to the lower portion of the flocculation zone 1d. Based on Bernoulli's principle, as muddy water flows through the flocculation zone 1d, the cross-sectional area decreases from the upper portion to the lower portion, increasing the flow rate of the muddy water. This can further increase the flow rate at the end of the baffle channel. With this increased flow rate, the flocculent sediment at the end of the baffle channel is less likely to remain at the bottom of the flocculation sedimentation tank 1, thereby extending the cleaning cycle of the flocculation sedimentation tank, or even eliminating the need for cleaning the flocculation sedimentation tank.

[0016] Mud-laden wastewater and PAM flocculant are simultaneously introduced into the mud inlet 1a, where they flow and flocculate in the baffled channel until they are discharged. The names of the mixing zone 1c, flocculation zone 1d, and discharge zone 1e do not limit the specific processes within these zones. Preferably, the volumes of the mixing zone 1c, flocculation zone 1d, and discharge zone 1e gradually decrease.

[0017] The partition 2 includes a first vertical partition and a second vertical partition, which are arranged parallel to each other, along the direction from the mud inlet 1a to the mud outlet 1b, with the first vertical partition being closer to the mud inlet 1a and the second vertical partition being closer to the mud outlet 1b. The arrangement of the first and second vertical partitions prevents the mud and water in the flocculation and sedimentation tank 1 from turning in multiple directions, thereby enhancing flow performance.

[0018] An inclined contraction slope 2a is provided at the upper portion of the first vertical partition. The upper edge of the contraction slope 2a extends to the mixing zone 1c, and the lower edge of the contraction slope 2a extends to the flocculation zone 1d.

[0019] To facilitate installation and manufacturing, the first vertical partition includes a first partition, a second partition and a contraction inclined plate. The first partition and the second partition are arranged vertically and parallel. The bottom edge and two vertical side edges of the first partition are connected to the inner wall of the flocculation sedimentation box 1. The first partition is close to the mud inlet 1a. The bottom edge and two vertical side edges of the second partition are connected to the inner wall of the flocculation sedimentation box 1. The second partition is close to the second vertical partition. The height of the second partition is less than the height of the first partition. The upper edge of the contraction inclined plate is connected to the upper edge of the first partition, the lower edge of the contraction inclined plate is connected to the upper edge of the second partition, the inner side surface of the contraction inclined plate forms the contraction inclined surface 2a, and the other two edges of the contraction inclined plate are connected to the inner wall of the flocculation sedimentation box 1. The upper deflection port is formed between the upper edge of the first partition and the top plate of the flocculation sedimentation tank 1; the second vertical partition is a vertically arranged third partition, both vertical side edges of the third partition are connected to the inner wall of the flocculation sedimentation tank 1, and the lower deflection port is formed between the lower edge of the third partition and the bottom plate of the flocculation sedimentation tank 1, and the horizontal height of the upper edge of the third partition is greater than the horizontal height of the upper edge of the first partition.

[0020] To improve the muddy-water flow performance at the end of the baffle channel and prevent flocculent sediment from entering dead corners, a first diversion slope 1f is configured at the bottom of the flocculation zone 1d, facing the discharge zone 1e. A second diversion slope 1g is configured at the bottom of the discharge zone 1e, facing the flocculation zone 1d.

[0021] The first guide slope 1f and the second guide slope 1g may also be formed by the surfaces of independently provided guide slopes.

[0022] To enhance the mixing effect of the flocculant and aqueous sludge, a stirring device 3 is provided in each of the mixing zone 1c and the flocculation zone 1d. The power unit of the stirring device 3 is located at the top of the flocculation and sedimentation tank 1, and the paddles of the stirring device 3 extend into the mixing zone 1c and the flocculation zone 1d. Because the volume of the mixing zone 1c is larger than that of the flocculation zone 1d and the volume of the discharge zone 1e, the flocculation and sedimentation reactions can be completed in the mixing zone 1c and the flocculation zone 1d, and therefore, the stirring device 3 is not required in the discharge zone 1e.

[0023] The mud inlet 1a has a larger passage area than the mud outlet 1b. A sealing block 4 is located above the discharge area 1e. The sealing block 4 can be made of rubber. Its primary purpose is to remove as much mud and water as possible from the end of the baffle channel by siphoning when the flocculation and sedimentation tank 1 needs to be shut down, thereby reducing the amount of residual mud and water in the tank.

[0024] The top of the flocculation sedimentation box 1 is open and provided with a box cover, and the sealing block 4 is fixed to the lower surface of the box cover.

[0025] Beneficial Effects: The technical solution of this utility model can accelerate the end section of the mud-water mixture flowing through the baffle channel in the flocculation sedimentation tank, preventing flocculent sediment from gathering and accumulating at the end section of the baffle channel, thereby extending the cleaning cycle of the flocculation sedimentation tank and even eliminating the need to clean the flocculation sedimentation tank. This provides better protection for the continuous and stable progress of the sludge concentration and dehydration process.

[0026] 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 sludge concentration and dehydration pre-flocculation and sedimentation device, comprising a flocculation and sedimentation tank (1), wherein two opposing tank walls of the flocculation and sedimentation tank (1) are respectively provided with a mud inlet (1a) and a mud outlet (1b), and two vertically arranged partitions (2) are arranged between the mud inlet (1a) and the mud outlet (1b), and the two partitions (2) divide the internal area of ​​the flocculation and sedimentation tank (1) into a mixing area (1c), a flocculation area (1d) and a discharge area (1e), characterized in that: The mud inlet (1a) is in communication with the lower part of the mixing zone (1c), the upper part of the mixing zone (1c) is in communication with the upper part of the flocculation zone (1d), the lower part of the flocculation zone (1d) is in communication with the lower part of the discharge zone (1e), and the middle part of the discharge zone (1e) is in communication with the mud outlet (1b); The cross-sectional area of ​​the upper portion of the flocculation zone (1d) is larger than the cross-sectional area of ​​the lower portion thereof, and the upper portion of the flocculation zone (1d) transitions naturally to the lower portion thereof.

2. The sludge concentration and dehydration pre-flocculation sedimentation device according to claim 1 is characterized by: The bottom of the flocculation zone (1d) is provided with a first flow guiding slope (1f), and the first flow guiding slope (1f) faces the discharge zone (1e).

3. The sludge concentration and dehydration pre-flocculation sedimentation device according to claim 1 is characterized by: The bottom of the discharge zone (1e) is provided with a second flow guiding slope (1g), and the second flow guiding slope (1g) faces the flocculation zone (1d).

4. The sludge concentration and dehydration pre-flocculation sedimentation device according to claim 1 is characterized in that: A stirring device (3) is respectively arranged in the mixing zone (1c) and the flocculation zone (1d). The power part of the stirring device (3) is arranged on the top of the flocculation sedimentation tank (1), and the blades of the stirring device (3) extend into the mixing zone (1c) and the flocculation zone (1d).

5. The sludge concentration and dehydration pre-flocculation sedimentation device according to claim 1 is characterized in that: The passage area of ​​the mud inlet (1a) is larger than the passage area of ​​the mud outlet (1b), and a sealing block (4) is arranged on the upper part of the discharge area (1e).

6. The sludge concentration and dehydration pre-flocculation sedimentation device according to claim 1, characterized in that: The partition portion (2) comprises a first vertical partition and a second vertical partition which are parallel to each other. The first vertical partition and the second vertical partition are sequentially arranged along the direction from the mud inlet (1a) to the mud outlet (1b). The first vertical partition is close to the mud inlet (1a), and the second vertical partition is close to the mud outlet (1b).

7. The sludge concentration and dehydration pre-flocculation sedimentation device according to claim 6, characterized in that: The upper portion of the first vertical partition is provided with an inclined contraction slope (2a), the upper edge of the contraction slope (2a) extends to the mixing zone (1c), and the lower edge of the contraction slope (2a) extends to the flocculation zone (1d).

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