Intelligent control system for sludge backflow and sludge discharge

Abstract

The utility model relates to an intelligent control system for sludge backflow and sludge discharge. A mixed liquid output pipe with a flow regulating valve is arranged in a water collection and distribution well and a secondary sedimentation tank, wherein a liquidometer and an ORP potentiometer are arranged in the water collection and distribution well; the secondary sedimentation tank internally provided with a sludge interface instrument is provided with a sludge reverse feeding pipe with a sludge sleeve valve towards the water collecting and distributing well; the water collecting and distributing well is also provided with a sludge discharge pipe with a sludge discharge pump and a sludge flow pipe with a sludge reflux pump; and the controller is connected with each electric control element. When the sludge interface instrument exceeds a preset value, the controller increases the opening degree of the sludge sleeve valve until the sludge thickness cannot be reduced, and the opening degree of the flow regulating valve is reduced; when the liquidometer exceeds a preset value, the controller increases the opening degree of the flow regulating valve and increases the frequency of the sludge reflux pump at the same time; and when the ORP potentiometer exceeds a preset value, the controller increases the frequency of the sludge discharge pump and reduces the frequency of the sludge reflux pump at the same time, and the three controls are independent from each other and interact with each other, so that the activity of the returned sludge is ensured while the reasonable sludge thickness of the secondary sedimentation tank is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of equipment and facilities of sewage treatment plants, in particular to an intelligent control system for sludge return and sludge discharge. Background Art

[0002] In a sewage treatment plant, the mud-water mixture enters the water distribution well from the biochemical pool and is distributed to multiple identical secondary sedimentation tanks. The mud-water mixture entering the secondary sedimentation tank is divided into supernatant and mud layer after sedimentation. The supernatant will enter the next treatment procedure, and when the mud layer height exceeds 2.5 meters, there will be a risk of overflowing the pool and affecting the normal operation of the secondary sedimentation tank. Therefore, the bottom sludge in the secondary sedimentation tank needs to be regularly returned to the water distribution well.

[0003] At present, two groups of pipes are usually set up between the water collection and distribution well and the secondary sedimentation tank of the sewage treatment plant. One group of pipes relies on the height pressure difference to transport the mud-water mixture, and the other group of pipes uses the siphon principle to return the sludge. Both cannot be accurately and timely controlled. Among them, the untimely return of sludge and the excessive input of mixed liquid into the secondary sedimentation tank will increase the thickness of the mud layer within a certain period of time; at the same time, part of the sludge returned from the secondary sedimentation tank to the water collection and distribution well will settle at the bottom of the well, and the sludge suction pump at the bottom of the water collection and distribution well will pump the sludge at the pump mouth to the desludge room for sludge discharge treatment, while the other part of the sludge is mixed with most of the liquid in the water collection and distribution well due to the impact of the water flow and is sucked back to the anaerobic section of the biochemical pool through the pump. There is NO3-N in the return sludge. The higher its concentration, the higher the ORP value. When too much NO3-N is brought back to the anaerobic section, it will interfere with the release of phosphorus, reduce the phosphorus removal efficiency, and thus affect the denitrification effect. Therefore, how to control NO3-N in the return sludge is also a problem to be solved. Utility Model Content

[0004] Therefore, the technical problem to be solved by the utility model is to overcome the problem in the prior art that the mud layer height of the secondary sedimentation tank of the sewage treatment plant cannot be automatically adjusted and the NO3-N concentration in the return sludge is uncontrollable.

[0005] In order to solve the above technical problems, the utility model provides an intelligent control system for sludge return and sludge discharge, which is used to automatically adjust the sludge-water mixture flowing from the water collection and distribution well to the secondary sedimentation tank and the sludge returned from the secondary sedimentation tank to the water collection and distribution well, including:

[0006] A mixed liquid output pipe, the mixed liquid output pipe is arranged between the water collecting and distributing well and the secondary sedimentation tank, and a flow regulating valve is arranged on the mixed liquid output pipe;

[0007] A liquid level meter, which is also arranged in the water collection and distribution well;

[0008] A sludge return pipe, which is arranged between the secondary sedimentation tank and the water collection and distribution well, and is provided with a sludge sleeve valve;

[0009] A sludge interface meter, wherein the sludge interface meter is arranged in the secondary sedimentation tank;

[0010] A mud discharge pipe, one end of which is provided with a mud discharge pump, and the mud discharge pump is arranged at the bottom of the water collection and distribution well;

[0011] A sludge return pipe, one end of which is connected to a water collecting and distribution well, and a sludge return pump is provided on the sludge return pipe;

[0012] ORP potentiometer, the ORP potentiometer is arranged in the water collection and distribution well;

[0013] A controller is connected to the flow regulating valve, the liquid level meter, the sludge sleeve valve, the sludge interface meter, the sludge discharge pump, the sludge return pump and the ORP potentiometer. The controller simultaneously adjusts the opening of the sludge sleeve and the flow regulating valve according to the data signal fed back by the sludge interface meter. The controller also simultaneously adjusts the opening of the flow regulating valve and the suction frequency of the sludge return pump according to the data signal fed back by the liquid level meter. The controller also simultaneously adjusts the suction frequencies of the sludge return pump and the sludge discharge pump according to the data signal of the ORP potentiometer.

[0014] In one embodiment of the utility model, it also includes a mixed liquid input pipe, one end of which is connected to the water collection and distribution well.

[0015] In one embodiment of the utility model, a flow switch is also provided on the sludge return pipe, and the flow switch is connected to the controller.

[0016] In one embodiment of the present utility model, the flow switch is arranged on the sludge return pipe at a position close to the outlet of the sludge return pump.

[0017] The above technical solution of the utility model has the following advantages compared with the prior art:

[0018] The intelligent control system for sludge return and discharge described in the utility model sends a signal to the controller when the sludge interface meter recognizes that the sludge height in the secondary sedimentation tank exceeds a preset value, and the controller increases the opening of the sludge sleeve valve until the mud layer height reaches the standard; when the sludge sleeve valve reaches the maximum opening and still cannot continue to reduce the mud layer height, the flow regulating valve opening is reduced to reduce the flow of the mud-water mixture entering the secondary sedimentation tank; when the liquid level meter in the water collection and distribution well exceeds the preset value, the signal is sent to the controller, and the controller increases the opening of the flow regulating valve and increases the sludge layer height. The suction frequency of the mud return pump is used to reduce the liquid level of the mud-water mixture in the water collection and distribution well; when the ORP potentiometer in the water collection and distribution well recognizes that the ORP value in the mixed liquid exceeds the preset value, the controller will increase the suction frequency of the mud pump and reduce the suction frequency of the sludge return pump to ensure that the NO3-N concentration in the return sludge remains at a low value. The three controls are independent of each other but interact with each other, which can not only ensure that the mud layer thickness in the secondary sedimentation tank is within a reasonable range to prevent mud overflow, but also ensure that the return sludge entering the biochemical tank maintains a good activity. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein

[0020] Figure 1 The utility model is a schematic diagram of the overall structure of the intelligent control system for sludge return and sludge discharge.

[0021] Explanation of the reference numerals in the drawings in the specification: 1. water collecting and distribution well; 2. secondary sedimentation tank; 3. mixed liquor output pipe; 4. flow regulating valve; 5. liquid level meter; 6. sludge return pipe; 7. sludge sleeve valve; 8. sludge interface meter; 9. sludge discharge pipe; 10. sludge discharge pump; 11. sludge return pipe; 12. sludge return pump; 13. ORP potentiometer; 14. controller; 15. flow switch; 16. mixed liquor input pipe. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0023] Reference Figure 1 As shown, the utility model provides an intelligent control system for sludge return and sludge discharge, which is used to automatically adjust the sludge-water mixture flowing from the water collection and distribution well 1 to the secondary sedimentation tank 2 and the sludge returned from the secondary sedimentation tank 2 to the water collection and distribution well 1, including:

[0024] A mixed liquid output pipe 3, which is arranged between the water collecting and distributing well 1 and the secondary sedimentation tank 2, and a flow regulating valve 4 is arranged on the mixed liquid output pipe 3;

[0025] Liquid level meter 5, which is also arranged in the water collecting and distributing well 1;

[0026] A sludge return pipe 6 is provided between the secondary sedimentation tank 2 and the water collection and distribution well 1, and a sludge sleeve valve 7 is provided on the sludge return pipe 6;

[0027] The sludge interface meter 8 is arranged in the secondary sedimentation tank 2;

[0028] A mud discharge pipe 9, one end of which is provided with a mud discharge pump 10, and the mud discharge pump 10 is arranged at the bottom of the water collection and distribution well 1;

[0029] A sludge return pipe 11, one end of which is connected to the water collecting and distributing well 1, and a sludge return pump 12 is arranged on the sludge return pipe 11;

[0030] ORP potentiometer 13, ORP potentiometer 13 is arranged in the water collection and distribution well 1;

[0031] The controller 14 is connected to the flow regulating valve 4, the liquid level meter 5, the sludge sleeve valve 7, the sludge interface meter 8, the sludge pump 10, the sludge return pump 12 and the ORP potentiometer 13. The controller 14 automatically adjusts the opening of the sludge sleeve and the flow regulating valve 4 according to the data signal fed back by the sludge interface meter 8. The controller 14 also automatically adjusts the opening of the flow regulating valve 4 and the suction frequency of the sludge return pump 12 according to the data signal fed back by the liquid level meter 5. The controller 14 also automatically adjusts the suction frequency of the sludge return pump 12 and the sludge pump 10 according to the data signal of the ORP potentiometer 13.

[0032] This intelligent control system for sludge return and discharge, when the sludge interface meter 8 recognizes that the sludge height in the secondary sedimentation tank 2 exceeds the preset value, it sends a signal to the controller 14, and the controller 14 increases the opening of the sludge sleeve valve 7 until the mud layer height reaches the standard. When the sludge sleeve valve 7 reaches the maximum opening and still cannot continue to reduce the mud layer height, the flow regulating valve 4 is opened to reduce the flow of the mud-water mixture entering the secondary sedimentation tank 2; when the liquid level meter 5 in the water collection and distribution well 1 exceeds the preset value, the signal is sent to the controller 14, and the controller 14 will increase the opening of the flow regulating valve 4 and increase the sludge return The suction frequency of the flow pump 12 is used to reduce the liquid level of the mud-water mixture in the water collection and distribution well 1; when the ORP potentiometer 13 in the water collection and distribution well 1 recognizes that the ORP value in the mixed liquid exceeds the preset value, the controller 14 will increase the suction frequency of the sludge pump 10 and reduce the suction frequency of the sludge return pump 12 to ensure that the NO3-N concentration in the return sludge remains at a low value. The three controls are independent of each other but interact with each other, which can ensure that the mud layer thickness of the secondary sedimentation tank 2 is within a reasonable range to prevent mud overflow, and at the same time ensure that the return sludge entering the biochemical tank maintains a good activity.

[0033] Specifically, each pump, valve component and measuring instrument are electrical components and are controllable. The sludge discharge pipe 9 leads to the desludge room. In this embodiment, the original design of the pipeline is not changed. A sludge interface meter 8 is added in the secondary sedimentation tank 2, and an ORP potentiometer is added in the water collection and distribution well 1. At the same time, each pump component and valve component is connected to the controller 14. The controller 14 is a PLC controller 14, which is simple and reliable. The internal control system realizes precise control of sludge return and sludge discharge through data coupling comprehensive analysis and calculation through feedforward + feedback + algorithm, which can not only ensure the long-term normal operation of the equipment, but also achieve the purpose of energy saving and consumption reduction; in this embodiment, there are four secondary sedimentation tanks 2, and the flow regulating valves 4 between the four secondary sedimentation tanks 2 and the water collection and distribution well 1 can also interact with each other, that is, when the sludge layer thickness of one of the secondary sedimentation tanks 2 exceeds the standard, the mixed liquor supply to the remaining secondary sedimentation tanks 2 can be increased first.

[0034] Furthermore, it also includes a mixed liquid input pipe 16 , one end of which is connected to the water collection and distribution well 1 .

[0035] Specifically, the mixed liquid input pipe 16 is used to connect to the biochemical pool.

[0036] Furthermore, a flow switch 15 is provided on the sludge return pipe 11 , and the flow switch 15 is connected to the controller 14 .

[0037] Specifically, the flow switch 15 is used to feed back the working efficiency of the sludge return pump 12 to ensure that the controller 14 accurately controls the sludge return pump 12 .

[0038] Furthermore, the flow switch 15 is arranged on the sludge return pipe 11 at a position close to the outlet of the sludge return pump 12 .

[0039] Specifically, the flow switch 15 is disposed at the outlet of the sludge return pump 12 to more accurately feedback the flow change of the sludge return pump 12 .

[0040] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention of the utility model.

Claims

1. An intelligent control system for sludge return and discharge, used for automatically adjusting the mud-water mixture flowing from the water collection and distribution well to the secondary sedimentation tank and the sludge returned from the secondary sedimentation tank to the water collection and distribution well, characterized in that: include: A mixed liquid output pipe, the mixed liquid output pipe is arranged between the water collecting and distributing well and the secondary sedimentation tank, and a flow regulating valve is arranged on the mixed liquid output pipe; A liquid level meter, which is also arranged in the water collection and distribution well; A sludge return pipe, which is arranged between the secondary sedimentation tank and the water collection and distribution well, and is provided with a sludge sleeve valve; A sludge interface meter, wherein the sludge interface meter is arranged in the secondary sedimentation tank; A mud discharge pipe, one end of which is provided with a mud discharge pump, and the mud discharge pump is arranged at the bottom of the water collection and distribution well; A sludge return pipe, one end of which is connected to a water collecting and distribution well, and a sludge return pump is provided on the sludge return pipe; An ORP potentiometer, wherein the ORP potentiometer is arranged in a water collection and distribution well; A controller is connected to the flow regulating valve, the liquid level meter, the sludge sleeve valve, the sludge interface meter, the sludge discharge pump, the sludge return pump and the ORP potentiometer. The controller simultaneously adjusts the opening of the sludge sleeve and the flow regulating valve according to the data signal fed back by the sludge interface meter. The controller also simultaneously adjusts the opening of the flow regulating valve and the suction frequency of the sludge return pump according to the data signal fed back by the liquid level meter. The controller also simultaneously adjusts the suction frequencies of the sludge return pump and the sludge discharge pump according to the data signal of the ORP potentiometer.

2. The intelligent control system for sludge return and discharge according to claim 1 is characterized in that: It also includes a mixed liquid input pipe, one end of which is connected to the water collection and distribution well.

3. The intelligent control system for sludge return and discharge according to claim 1 is characterized in that: The sludge return pipe is also provided with a flow switch, and the flow switch is connected to the controller.

4. The intelligent control system for sludge return and discharge according to claim 3 is characterized in that: The flow switch is arranged on the sludge return pipe at a position close to the outlet of the sludge return pump.

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