CN113797604A - Sedimentation tank with scum separation mechanism and use method thereof - Google Patents

Abstract

The invention relates to a sedimentation tank with a scum separation mechanism, which comprises a tank body, a water outlet part and a first scum outlet weir, wherein the first scum outlet weir is arranged on the inner wall of the upper part of the tank body in a mode of surrounding the whole inner wall of the tank body, so that the water surface in the tank body is not contacted with the inner wall of the tank body, the inlet of the first scum outlet weir is flush with the water surface in the tank body, so that scum is carried by the upper clear water on the upper part of the tank body and enters the first scum outlet weir, and the water outlet part is the water outlet weir arranged below the first scum outlet weir and/or a second water outlet pipe arranged at the lower part of the first scum outlet weir. According to the sedimentation tank with the scum separation mechanism, the scum can be separated and discharged synchronously with the separation of mud and water and the discharge of water and mud without being influenced by external wind, and the scum separation effect and the capability of resisting external interference of the sedimentation tank can be obviously improved.

Description

Sedimentation tank with scum separation mechanism and use method thereof

Technical Field

The invention relates to the field of biological sewage treatment, in particular to a sedimentation tank with a scum separation mechanism and a use method thereof.

Background

In the sewage biological treatment industry, when activated sludge mainly composed of various organisms is subjected to sludge-water separation operation in a sedimentation tank, if the activated sludge floats to the water surface for various reasons, the sludge floating phenomenon can be caused. The sludge floating on one hand can cause the mud-water separation effect to be poor, so that the concentration of organic matters and the concentration of suspended solids in the effluent are increased, and on the other hand, the sludge amount returning to the aeration tank can be reduced, thereby bringing difficulty to the control of the biological sewage treatment. In addition, the impurities which are difficult to degrade and have density smaller than that of water in the sewage or the floating impurities which accidentally fall into the sedimentation tank from the external environment can flow out along with the supernatant on the water surface, so that the quality of the effluent water is reduced. Therefore, it is important to separate and remove scum composed of floating sludge and various floatable impurities in a sedimentation tank (such as a secondary sedimentation tank) to ensure the quality of effluent. However, the techniques of mechanical scraping and membrane filtration for separating scum in the prior art often have the problems of poor separation effect, overhigh construction or operation cost, complex structure or operation and the like. Accordingly, there remains a need for an improved settling tank having a scum separation mechanism.

Disclosure of Invention

It is an object of the present invention to provide a settling tank with a dross separation mechanism to solve the aforementioned problems of the prior art. Specifically, the present invention provides the following technical solutions.

In one aspect, the present invention provides a sedimentation tank having a scum separating mechanism, comprising a tank body, a water outlet portion, and a first scum weir, the first scum weir being provided on an upper inner wall of the tank body in such a manner as to surround the entire inner wall of the tank body so that a water surface in the tank body does not contact the inner wall of the tank body, and the inlet of the first slag outlet weir is flush with the water surface in the tank body, so that when the mixed liquid is introduced into the tank body, the floating slag floating on the water surface in the tank body is carried by the supernatant on the upper part of the tank body and enters the first slag outlet weir, the water outlet part is a water outlet weir arranged below the first slag outlet weir and is provided with a water outlet weir inlet positioned below the water surface in the tank body for discharging supernatant on the upper part of the tank body, and/or a second water outlet pipe arranged at the lower part of the first slag weir and provided with a water outlet pipe inlet positioned below the water surface in the first slag weir for discharging supernatant in the first slag weir.

Further, a second slag weir is arranged inside the first slag weir, and the inlet of the second slag weir is lower than the inlet of the first slag weir and is flush with the water surface in the first slag weir, so that the floating slag in the first slag weir is carried into the second slag weir by the supernatant in the first slag weir.

Further, the second slag weir encircles the whole inner wall of the tank body.

Further, the second slag weir is one or more slag pipes dispersed in the first slag weir, and an inlet end face of the one or more slag pipes is flush with the water surface in the first slag weir so that the scum floating in the first slag weir is entrained by the supernatant in the first slag weir.

Furthermore, the lower part of the tank body is also provided with an aeration device for aerating the mixed liquid in the tank body.

Furthermore, the lower part of the tank body is also provided with a sludge discharge pipe for discharging the concentrated mixed liquid at the lower part of the tank body.

In another aspect, the present invention provides a dross separation method for a sedimentation tank, comprising the steps of:

s00, providing the sedimentation tank with a dross separation mechanism according to any one of claims 1 to 5;

s10, introducing the mixed liquid with the flow rate of Q1 into the pool body, and separating mud and water in the pool body;

s20, when no floating slag exists on the water surface in the pool body, discharging the concentrated mixed liquor with the flow rate of Q2 from the lower part of the pool body, discharging the first supernatant with the flow rate of Q3 from the effluent part, and discharging the second supernatant with the flow rate of Q4 from the first slag discharging weir, wherein Q1 is Q2+ Q3+ Q4, and Q3+ Q4 is more than 0;

s30, when scum appears on the water surface in the tank, discharging the concentrated mixed liquor with a flow rate of Q2 from the lower part of the tank, discharging the first supernatant with a flow rate of Q3 'from the effluent part, discharging the second supernatant with a flow rate of Q4' from the first slag weir, and discharging the scum with a flow rate of Q5 from the first slag weir, wherein Q1 is Q2+ Q3'+ Q4' + Q5, and Q5> 0.

Further, in steps S20 and S30, Q3 and Q3 'are greater than 0, and Q4 and Q4' are equal to 0.

Further, in steps S20 and S30, Q3 and Q3 'are equal to 0, and Q4 and Q4' are greater than 0.

Further, in steps S20 and S30, Q3 and Q3 'are greater than 0, and Q4 and Q4' are greater than 0.

Further, the following steps are included before step S10:

s02, introducing mixed liquid with the flow rate of Q1' into the pool body, starting an aeration device to aerate the mixed liquid in the pool body so as to carry floatable sludge and impurities in the mixed liquid to float to the water surface,

s04, discharging the dross with a flow rate of Q5' from the first tapping weir, wherein Q1' is Q5 '.

According to the sedimentation tank with the scum separation mechanism, the scum can be separated and discharged synchronously with the separation of mud and water and the discharge of water and mud without being influenced by external wind, and the scum separation effect and the capability of resisting external interference of the sedimentation tank can be obviously improved.

The terms used herein have their meanings well known in the art, however for clarity the following definitions are still given.

The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the invention, and are not intended to indicate or imply that the referenced devices or elements must be in a particular orientation, constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. It should be noted that unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly and include, for example, fixed or removable connections or integral connections; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

"substantially" or "essentially" does not exclude the meaning of "completely". For example, a component "substantially free" of Y may also be completely free of Y. Where a particular value is defined, it is meant that the particular value has a range that floats above and below the particular value, which may be +/-5%, +/-4%, +/-3%, +/-2%, +/-1%, +/-0.5%, +/-0.2%, +/-0.1%, +/-0.05%, +/-0.01%, etc., of the particular value. If desired, "substantially" or "essentially" may be substituted for or deleted from the definition of the invention with the above floating ranges. "comprising" includes both the recited factors and also allows for the inclusion of additional, non-deterministic factors. "about," "about," or "approximately," when defining a particular value, means that the particular value has a range that varies from top to bottom based on the particular value, and the range can be +/-5%, +/-4%, +/-3%, +/-2%, +/-1%, +/-0.5%, +/-0.2%, +/-0.1%, +/-0.05%, +/-0.01%, etc., of the particular value.

Drawings

Fig. 1 is a schematic view showing a structure of a settling tank having a dross removal mechanism according to an embodiment of the present invention.

The meanings of the symbols in the figure are as follows: 1-sedimentation tank, 10-tank wall, 11-effluent weir, 111-effluent weir inlet, 12-first slag weir, 13-second slag weir, 2-water inlet pipe, 21-water inlet valve, 3-air inlet pipe, 31-air inlet valve, 4-mud discharge pipe, 41-mud discharge valve, 5-first water outlet pipe, 51-first water outlet valve, 6-second water outlet pipe, 61-second water outlet valve, 7-slag discharge pipe, 71-slag discharge valve and 8-aeration device.

Detailed Description

Some embodiments of the invention are further described below with reference to the drawings, but are not intended to limit the scope of the invention.

The invention is further illustrated by the following examples in conjunction with the accompanying drawings:

as shown in fig. 1, the sedimentation tank with a scum removing mechanism of the present invention comprises a tank body 1, a water inlet pipe 2 is disposed at the lower part of the tank body 1 for introducing a mixed liquid to be subjected to sludge-water separation into the tank body 1, a first scum outlet weir 12 is disposed on the inner wall of the upper part of the tank body 1, the first scum outlet weir 12 surrounds the entire inner wall of the tank body 1 and is flush with the water surface in the tank body 1 so that the water surface in the tank body 1 does not contact with the inner wall of the tank body 1, and scum consisting of sludge and/or other impurities floating on the water surface is entrained by the supernatant at the upper part of the tank body 1 and enters the first scum outlet weir 12 when the mixed liquid is continuously introduced into the tank body 1.

In some cases, an effluent weir 11 is provided below the first effluent weir 12, a first effluent pipe 5 is provided at the lower part of the effluent weir 11, and a gap between the upper end of the effluent weir 11 and the bottom of the first effluent weir 12 is used as an effluent weir inlet 111, so that the supernatant of the upper part of the tank body 1 enters the effluent weir 11 from the effluent weir inlet 111 and is discharged as effluent from the first effluent pipe 5. The outlet weir inlet 111 is arranged below the first slag outlet weir 12, so that sludge and impurities in the tank body 1 (particularly on the water surface) can be effectively prevented from settling into the tank body. In addition, the bottom of the first slag weir 12 and the side wall of the inlet 111 of the effluent weir are both inclined, so that the accumulation of sludge or impurities can be effectively avoided, and the accumulated sludge and impurities are prevented from entering the effluent weir 11.

In some cases, a second slag weir 13 is further provided inside the first slag weir 12, the second slag weir 13 is slightly lower than the first slag weir 12 and is flush with the water surface inside the first slag weir 12 so that the scum floating on the water surface in the first slag weir 12 is entrained by the supernatant on the upper portion of the first slag weir 12 into the second slag weir 13, and the scum in the second slag weir 13 is discharged through the slag pipe 7. In some cases, the scum discharged from the slag outlet pipe 7 may be directed to an upstream conditioning or aeration tank for further processing. In some cases, the second slag weir 13 may be disposed around the entire inner wall of the tank body 1. In other cases (not shown), the second slag weir 13 may be a plurality of (e.g., 2-12, e.g., 4, 6, 8, 10) slag pipes 7 scattered in the first slag weir 12 with their inlet end faces flush with the water surface inside the first slag weir 12.

In some cases, a second water outlet pipe 6 is arranged at the lower part of the first slag weir 12 so as to discharge the supernatant entering the first slag weir 12 as effluent; alternatively, for example, supernatant discharged from the second outlet pipe 6 may be led into the first outlet pipe 5 as part of the outlet water.

In some cases, the lower part of the tank body 1 can be further provided with an aeration device 8, and the aeration device 8 is connected with the air inlet pipe 3 so as to introduce aeration gas into the tank body 1 to aerate the mixed liquid in the tank body when needed, so that sludge and impurities which can float upwards in the tank body can quickly float upwards to the water surface, thereby accelerating the separation of scum.

In some cases, the lower part of the tank body 1 is further provided with a sludge discharge pipe 4 so as to discharge concentrated mixed liquor (or called sludge) in the lower part of the tank body 1 when needed, and the discharged sludge can be returned to an upstream aeration tank, for example.

In some cases, the water inlet pipe 2 is provided with a water inlet valve 21, the air inlet pipe 3 is provided with an air inlet valve 31, the sludge discharge pipe 4 is provided with a sludge discharge valve 41, the first water outlet pipe 5 is provided with a first water outlet valve 51, the second water outlet pipe 6 is provided with a second water outlet valve 61, and the residue discharge pipe 7 is provided with a residue discharge valve, so that various desired residue discharge methods can be realized by controlling the valves.

The sedimentation tank with a dross separating mechanism according to the present invention, when implementing a slagging method using the sedimentation tank, comprises the steps of:

s10, under the condition that the air inlet valve 41 is closed, the water inlet valve 21 is controlled to introduce the mixed liquid with the flow rate of Q1 from the water inlet pipe 2 to the pool body 1, so that the mixed liquid is subjected to mud-water separation in the pool body 1,

s20, when there is no scum on the water surface in the tank body 1, controlling the sludge discharge valve 41 to obtain the concentrated mixed liquor (or called sludge) with the flow rate Q2 from the sludge discharge pipe 4, and controlling one or both of the first water outlet valve 51 and the second water outlet valve 61 to obtain the supernatant with the flow rate Q3 from the first water outlet pipe 5, and obtaining the supernatant with the flow rate Q4 from the second water outlet pipe 6, wherein Q1 is Q2+ Q3+ Q4, and Q3+ Q4>0, that is, the supernatant is discharged without scum;

s30, when scum appears on the water surface in the tank body 1, controlling one or both of the first outlet valve 51 and the second outlet valve 61 to obtain supernatant with flow rate Q3 'from the first outlet pipe 5, obtaining supernatant with flow rate Q4' from the second outlet pipe 6, and controlling the scum valve 71 to obtain scum with flow rate Q5 from the scum pipe 7, wherein Q1 is Q2+ Q3'+ Q4' + Q5, and Q5>0, namely, scum is discharged.

In some cases, in steps S20 and S30, Q3 and Q3 'are greater than 0, and Q4 and Q4' are equal to 0, i.e. all the supernatant is discharged from the first water outlet pipe 5.

In some cases, in steps S20 and S30, Q3 and Q3 'are equal to 0 and Q4 and Q4' are greater than 0, i.e. all the supernatant is discharged from second water outlet pipe 6.

In some cases, in steps S20 and S30, Q3 and Q3 'are greater than 0, and Q4 and Q4' are greater than 0, i.e. the supernatant is discharged from first water outlet pipe 5 and second water outlet pipe 6 simultaneously.

When the entering mixed liquid contains more scum, the Q3' can be properly reduced, so that more supernatant enters the first scum weir 12 to more quickly and more carry the scum on the water surface of the pool body 1 into the first scum weir 12. When scum is entrained in the supernatant from the second outlet pipe 6, Q4' can be reduced appropriately to allow more supernatant to enter the second weir 13 to more quickly and more entrain the scum in the first weir 12 into the second weir 13.

In some cases, in steps S20 and S30, Q2>0, i.e., the settling pond, is performing sludge-water separation in a continuous manner.

In some cases, in steps S20 and S30, Q2 is 0, that is, the sedimentation tank performs sludge-water separation in a batch manner, where the slagging method further includes:

s40, after the supernatant of the upper part of the tank body 1 is discharged, the water inlet valve 21 is closed, and the sludge discharge valve 41 is controlled so that Q2>0 to discharge the sludge of the lower part of the tank body.

In some cases, if the above deslagging method cannot effectively separate the scum in the mixed liquid discharged from the pool body 1, the following steps may be performed before the above step S10 to enhance the scum separation:

s02, closing the mud valve 41, the first outlet valve 5 and the second outlet valve 6, controlling the inlet valve 21 to introduce the mixed liquid with the flow rate Q1' from the inlet pipe 2 to the tank body 1, opening the inlet valve 41 to introduce the aeration gas from the inlet pipe to the aeration device 8 to aerate (preferably micro-aerate) the mixed liquid in the tank body 1, utilizing the micro bubbles generated by aeration to quickly entrain and float the floatable mud and impurities in the mixed liquid to the water surface,

s04, opening the slag discharging valve 71, so that the floating slag entrained by the mixed liquid at the water surface of the tank body 1 passes through the first slag discharging weir 12 and the second slag discharging weir 13 continuously, and then discharges the floating slag with a flow rate of Q5' from the slag discharging pipe 7, wherein Q1' is Q5 '.

In some cases, the above-described intermittent deslagging method further comprises:

s06, when the scum in the mixed liquor in the pool body 1 is basically removed, closing the air inlet valve 31 to stop aeration and optionally closing the water inlet valve 21 so as to complete sludge-water separation of the mixed liquor in the pool body 1.

The above-described deslagging method can be applied to a case where the mixed liquor of the tank body 1 contains a large amount of floatable sludge or impurities, in which scum formation and separation can be accelerated by aeration, and in which part of the sludge or impurities can be crushed by aeration so that the floatable part floats up to the water surface and the precipitable part settles, thereby performing scum separation more efficiently.

The invention can flexibly adjust the strength and frequency of scum separation by controlling each valve, thereby being suitable for various working conditions.

The water surface in the tank body 1 is surrounded by the first slag discharging weir 12 and is not contacted with the tank wall, so that the problem that scum is retained after approaching or contacting the tank wall and cannot be discharged along with supernatant is effectively avoided. Particularly, when wind (especially outdoor) blows through the sedimentation tank, the invention not only can not cause the problem that the scum is gathered at the tank wall and cannot be discharged, but also can utilize wind force in any direction to blow the scum to be accelerated to leave the water surface and enter the first scum outlet weir 12, thereby effectively improving and enhancing the scum separation effect of the sedimentation tank.

According to the sedimentation tank with the scum separation mechanism, the scum can be separated and discharged synchronously with mud-water separation and water and mud discharge, the sedimentation tank is not influenced by external wind power, the scum separation efficiency can be greatly improved, and the scum separation mechanism has the advantages of simple structure, low cost, convenience in operation and strong anti-interference capability, so that the sedimentation tank can be widely applied to the sewage biological treatment industry.

The above-described embodiments are merely preferred embodiments of the present invention, and should not be construed as limiting the present invention, and features in the embodiments and examples in the present application may be arbitrarily combined with each other without conflict. The protection scope of the present invention is defined by the claims, and includes equivalents of technical features of the claims. I.e., equivalent alterations and modifications within the scope hereof, are also intended to be within the scope of the invention.

The invention has been described above by way of example. It should be understood, however, that the present invention is by no means limited to these specific embodiments. Various modifications and changes may be made by those skilled in the art without departing from the scope of the invention.

Claims (10)

1. The utility model provides a sedimentation tank with dross separating mechanism which characterized in that, includes cell body, play water outlet portion and first slag weir, and first slag weir is located on the upper portion inner wall of cell body with the mode that encircles the whole inner wall of cell body so that the surface of water in the cell body does not contact with the inner wall of cell body to the entry and the cell body internal water level of first slag weir make when the leading-in cell body of mixed liquid floating dross on the surface of water in the cell body by cell body upper portion supernatant band entering first slag weir, play water outlet portion sets up the play water weir of the below of first slag weir and has the play water weir entry that is located cell body internal water level below and is used for discharging the supernatant on cell body upper portion, and/or set up the second outlet pipe of the lower part of first slag weir and have the play water inlet that is located first slag weir internal water level below and be used for discharging the supernatant in the first slag weir.

2. The sedimentation tank with the scum separating mechanism as claimed in claim 1, wherein a second scum weir is further provided inside the first scum weir, and an inlet of the second scum weir is lower than an inlet of the first scum weir and is flush with the water surface inside the first scum weir so that the scum floating in the first scum weir is entrained by the supernatant in the first scum weir into the second scum weir.

3. The sedimentation tank having a dross separation mechanism of claim 3, wherein the second slag weir is circumferentially disposed on an entire inner wall of the tank body.

4. The sedimentation tank with a scum separation mechanism as claimed in claim 3, wherein the second slag weir is one or more slag pipes dispersed in the first slag weir, and an inlet end face of the one or more slag pipes is flush with the water surface inside the first slag weir so that scum floating in the first slag weir is entrained by supernatant in the first slag weir into the first slag weir.

5. A sedimentation tank having a dross separation mechanism according to any one of claims 1 to 4, wherein an aeration apparatus is further provided at a lower portion of the tank body for aerating the mixed liquid in the tank body.

6. A scum separation method for a sedimentation tank comprises the following steps:

s00, providing the sedimentation tank with a dross separation mechanism according to any one of claims 1 to 5;

s10, introducing the mixed liquid with the flow rate of Q1 into the pool body, and separating mud and water in the pool body;

s20, when no floating slag exists on the water surface in the pool body, discharging the concentrated mixed liquor with the flow rate of Q2 from the lower part of the pool body, discharging the first supernatant with the flow rate of Q3 from the effluent part, and discharging the second supernatant with the flow rate of Q4 from the first slag discharging weir, wherein Q1 is Q2+ Q3+ Q4, and Q3+ Q4 is more than 0;

s30, when scum appears on the water surface in the tank, discharging the concentrated mixed liquor with a flow rate of Q2 from the lower part of the tank, discharging the first supernatant with a flow rate of Q3 'from the effluent part, discharging the second supernatant with a flow rate of Q4' from the first slag weir, and discharging the scum with a flow rate of Q5 from the first slag weir, wherein Q1 is Q2+ Q3'+ Q4' + Q5, and Q5> 0.

7. The dross separation method of claim 6, wherein in steps S20 and S30, Q3 and Q3 'are greater than 0 and Q4 and Q4' are equal to 0.

8. The dross separation method of claim 6, wherein in steps S20 and S30, Q3 and Q3 'are equal to 0, and Q4 and Q4' are greater than 0.

9. The dross separation method of claim 6, wherein in steps S20 and S30, Q3 and Q3 'are greater than 0 and Q4 and Q4' are greater than 0.

10. The dross separation method for a sedimentation tank of any one of claims 6 to 9, further comprising, before the step S10, the steps of:

s02, introducing mixed liquid with the flow rate of Q1' into the pool body, starting an aeration device to aerate the mixed liquid in the pool body so as to carry floatable sludge and impurities in the mixed liquid to float to the water surface,

s04, discharging the dross with a flow rate of Q5' from the first tapping weir, wherein Q1' is Q5 '.

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