CN103030209A - Effluent-adjustable weir device with nitrogen and phosphorus removal sewage treatment aeration tank and control method thereof - Google Patents

Effluent-adjustable weir device with nitrogen and phosphorus removal sewage treatment aeration tank and control method thereof Download PDF

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Publication number
CN103030209A
CN103030209A CN2012105333632A CN201210533363A CN103030209A CN 103030209 A CN103030209 A CN 103030209A CN 2012105333632 A CN2012105333632 A CN 2012105333632A CN 201210533363 A CN201210533363 A CN 201210533363A CN 103030209 A CN103030209 A CN 103030209A
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aeration tank
liquid level
weir
weir plate
gas blower
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蒋勇
王佳伟
高琼
崔春玥
李伟
尹新政
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Beijing Drainage Group Co Ltd
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Beijing Drainage Group Co Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/30—Wastewater or sewage treatment systems using renewable energies
    • Y02W10/33—Wastewater or sewage treatment systems using renewable energies using wind energy

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Abstract

The invention discloses an effluent-adjustable weir device with a nitrogen and phosphorus removal sewage treatment aeration tank and a control method thereof. The device is provided with the aeration tank, wherein a controllable electric valve is arranged on the blower of the aeration tank, and an adjustable weir plate is arranged at a water outlet. The device is also provided with a control device which comprises a weir plate transmission device, an on-line flow meter, an on-line liquid level meter and a programmable logic controller (PLC). The control method comprises the following steps of: 1) starting the adjustable weir control device, and setting a control initial value in the PLC; 2) calculating the required liquid level of the aeration tank; 3) feeding the actual liquid level value L1 back to the PLC from the liquid level meter; 4) adjusting the liquid level, the electric valve and the backpressure of the blower; and 5) repeating the steps 2-4. The device and the method are applied to effluent control of the aeration tank, a good sewage treatment effect is achieved, and the aeration energy consumption is reduced.

Description

But denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device and control method
Technical field
The invention belongs to a kind of sewage disposal technology, specifically device and the control method of the control of each aeration tank of a kind of sewage work liquid level, be used for changing adjustment aeration tank liquid level according to flooding velocity, adjust the reaction times, improve the stability of wastewater treatment efficiency, reduce simultaneously the gas blower back pressure, realize blast engine energy saving.Background technology
Sewage work generally designs the reaction times of aeration tank according to the water inlet daily mean, and then the volume of definite aeration tank and liquid level, and sets the gas blower back pressure.Because the variation of amount of inlet water in one day is larger, when flooding quantity was low, the aeration tank volume was excessive, reaction times is long, causes cell internal carbon source over oxidation, thereby makes denitrifying carbon source not enough, affect biological denitrificaion, then affect biological phosphate-eliminating, water outlet total nitrogen and total phosphorus raise.When flooding quantity was higher, the aeration tank volume was not enough, and the reaction times is inadequate, causes nitrification effect limited, and the water outlet ammonia nitrogen raises, and the water outlet total nitrogen also can increase.Therefore, the reaction times is not enough all can to affect microbic activity in the denitrification dephosphorization technique with surplus, makes the effluent quality variation.Be in the definite value situation at air quantity, the gas blower exhaust pressure is higher, and energy consumption is larger, and the height of gas blower exhaust pressure does not depend on blower fan itself, but gas after being discharged by gas blower the pipeline crushing and the situation of aeration tank liquid level, namely so-called " back pressure " determines.The top hole pressure that marks on the gas blower nameplate is the specified top hole pressure of blower fan.In fact, gas blower can be worked being lower than under any pressure of specified top hole pressure, and as long as intensity and exhaust temperature allow, also can surpass specified top hole pressure work.The too high oxygen supply aerating system that causes of gas blower back pressure need to overcome the extra back pressure that high-water brings, and has improved the energy consumption of blower fan.Therefore, variation can be adjusted the liquid level of aeration tank the adjustment of processing unit effluent weir according to amount of inlet water, and then realize adjusting aeration tank volume and gas blower back pressure according to the variation of flooding quantity, keep preferably Nitrogen/Phosphorus Removal, reduce the energy consumption of gas blower.Therefore, but the method that changes regulation and control aeration tank water outlet weir transfer liquid level according to flooding velocity sewage work is improved the denitrogenation dephosphorizing treatment effect and reduces aeration energy consumption and have practical significance.
Summary of the invention
The objective of the invention is in order to solve the problems of the technologies described above, but proposed a kind of denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device and control method, changed according to flooding velocity and adjust the aeration tank liquid level, adjusted the reaction times, reaching better wastewater treatment efficiency, and reduce aeration energy consumption.
The objective of the invention is to realize by following technical scheme:
But denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device, be provided with aeration tank (4), the treatment unit water outlet of aeration tank front end is communicated with in the waste disposal plant of the water-in of this aeration tank (1) and denitrogenation dephosphorizing sewage treatment process, the treatment unit water-in of rear end, aeration tank is communicated with in the waste disposal plant of the water outlet of this aeration tank and denitrogenation dephosphorizing sewage treatment process, the bottom, aeration tank is provided with aeration head (8), this aeration head and gas blower (10)) be communicated with, it is characterized in that: the pipeline between aeration head and gas blower is provided with controllable electric valve (9), be provided with adjustable weir plate (8) at the aeration tank water outlet, and being provided with control device, this control device comprises: weir plate drive unit (7), online under meter (3) and online liquidometer (2), PLC controller (5); Described online under meter is located on the water inlet pipe of aeration tank, and online liquidometer is located in the aeration tank, and the weir plate drive unit drives with adjustable weir plate and is connected; Described PLC controller and described online under meter, online liquidometer carry out signal and are connected, and control the control linkage of weir plate lifting with described weir plate drive unit, and with described controllable electric valve control linkage.
But 2, the control method of denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device according to claim 1 is characterized in that may further comprise the steps:
1) starts weir-adjustable control device, in the PLC controller, set the threshold range a of the control liquid level of aeration tank, set the comparison interval time T, set the hydraulic detention time HRT of aeration tank, set gas blower back pressure PSET, the floorage S of aeration tank sets adjustable weir plate single motion amplitude N; The threshold range a of this technique initialization liquid level is 0.01～0.05m, and comparison interval time T 1 is 1～60 minute, and adjustable weir plate single motion amplitude N scope is 1～50mm, and the hydraulic detention time HRT scope of aeration tank is 4～15 hours; Gas blower back pressure PSET scope is 0.04～0.10MPa; Valve single amplitude of accommodation F1 scope is 1-4%; It is 0.0001～0.005MPa that gas blower back pressure single is regulated the F2 scope.
2) utilize online under meter, flow signal Q1 of collection in per 5 minutes, unit: m 3/ min calculates required aeration tank liquid level L according to formula (1) Cal:
L cal = ( Σ i = 1 12 Q i * 5 ) * HRT / S Formula (1)
3) from liquidometer with actual liquid level value L iFeed back to the PLC controller, in the PLC controller, actual liquid level value L iWith the required level value L that calculates CalThreshold range, once compare every T;
4) as this actual liquid level value L iWithin computer capacity, namely at L Cal-a≤L i＜L CalBetween+a the value, then system continues operation, but the weir transfer state remains unchanged; As actual liquid level value L i＜L Cal-a starts adjustable weir plate drive unit, but improves weir transfer N mm, increases electrically operated valve aperture F1%, increases gas blower back pressure set value PSET F2MPa, with the minimizing aquifer yield, and increases air demand; As actual liquid level value L i＞=L Cal+ a, but the weir transfer drive unit started, but reduce weir transfer N mm, reduce electrically operated valve aperture F1%, reduce gas blower back pressure set value PSET F2 MPa, with the increasing aquifer yield, and reduce air demand;
5) step of repetition 2～4;
The cardinal principle of this device is: the hydraulic detention time HRT of aeration tank has determined the effect of denitrogenation dephosphorizing, but because the factors such as living habit, season, economic activity and city development level cause the fluctuation of Sewage Plant amount of inlet water very large, adjust the aeration tank liquid level by the variation according to flooding quantity, thereby realize adjusting according to the variation of flooding quantity the purpose of aeration tank volume and hydraulic detention time HRT, guarantee stable Nitrogen/Phosphorus Removal and reduce the blast aeration energy consumption.
Device of the present invention and control method have the following advantages: simple to operate, the investment working cost is few, environmental influence is little, the aeration tank liquid level is changed in-20%～+ 10% scope of design load, that is: hydraulic detention time is changed in-20%～+ 10% scope of design load, improve denitrogenation dephosphorizing treatment effect 10%, reduce the average back pressure 5% of gas blower, reduce gas blower energy consumption 5%, solve amount of inlet water and changed the contradiction that can not change with the aeration tank volume, reduce the Sewage Plant power consumption, improved treatment effect.
Description of drawings
Fig. 1 is structural representation of the present invention;
Fig. 2 is the structural representation of adjustable weir plate end of the present invention.
Construction profile of the present invention is not subjected to the restriction of this figure, and only the variation of profile also belongs to the protection domain of this patent.
Embodiment
The present invention is described further below in conjunction with drawings and Examples:
Embodiment 1: referring to accompanying drawing, but denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device, be provided with aeration tank 4, the water-in 1 of this aeration tank is communicated with the treatment unit water outlet of aeration tank front end in the waste disposal plant of denitrogenation dephosphorizing sewage treatment process, the treatment unit water-in of rear end, aeration tank is communicated with in the waste disposal plant of the water outlet of this aeration tank and denitrogenation dephosphorizing sewage treatment process, the bottom, aeration tank is provided with aeration head 8, this aeration head is communicated with gas blower 10, it is characterized in that: the pipeline between aeration head and gas blower is provided with controllable electric valve 9, be provided with adjustable weir plate 8 at the aeration tank water outlet, and being provided with control device, this control device comprises: weir plate drive unit 7, online under meter 3 and online liquidometer 2, PLC controller 5; Described online under meter is located on the water inlet pipe of aeration tank, and online liquidometer is located in the aeration tank, and the weir plate drive unit drives with adjustable weir plate and is connected; Described PLC controller and described online under meter, online liquidometer carry out signal and are connected, and control the control linkage of weir plate lifting with described weir plate drive unit, and with described controllable electric valve control linkage.
Embodiment 2: but the control method of denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device may further comprise the steps:
1) starts the water outlet weir-adjustable control device, the dead zone range a that sets the control liquid level of each processing unit in controller is ± 0.01m, setting the comparison interval time T is 30 minutes, the hydraulic detention time HRT that sets the aeration tank is 7.5 hours, set gas blower back pressure 0.073MPa, the floorage 2217m of single group aeration tank 2, setting adjustable weir plate single motion amplitude N is 1 (mm), sets the parallel series of Sewage Plant and adds up to 6;
2) utilize online under meter, flow signal Q of collection in per 5 minutes i, calculate required aeration tank liquid level L according to formula (1) Cal, record front 12 groups of Q iBe 23.1,24.2,25,25.8,26.5,27.6,28.3,28.9,30.1,30.8,31.6,32.4,33.6, utilize formula (1) automatically to calculate L CalBe 6.22m
L cal = ( Σ i = 1 12 Q i * 5 ) * HRT / S Formula (1)
3) actual liquid level value L iBe 6.1m, but feed back to the weir transfer controller, in controller, actual liquid level value L iWith the required level value L that calculates Cal, threshold range once compared every 30 minutes.
4) this series actual liquid level value L iBe 6.1m, be lower than the computer capacity lower value, namely be lower than L Cal-a (6.22-0.01=6.21), but weir transfer transmission mechanism about startup, but weir transfer 2mm promoted, increase electrically operated valve aperture 1.5%, increase gas blower back pressure 0.0002MPa;
5) step of repetition 2～4;
Present embodiment is after trying out, the aeration tank liquid level is changed in 5.0～6.5m scope, hydraulic detention time changes in-17%～+ 8% scope of design load, total nitrogen concentration drops to 24mg/L from 31mg/L, improve treatment effect 22%, the average back pressure of gas blower drops to 0.071MPa from 0.076MPa, reduce by 6.6%, folk prescription drum wind energy consumption drops to 0.112kWh from 0.119kWh, reduce gas blower energy consumption 5.8%, solve amount of inlet water and changed the contradiction that can not change with the aeration tank volume, reduced the Sewage Plant power consumption, improved treatment effect.

Claims (2)

1. but denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device, be provided with aeration tank (4), the treatment unit water outlet of aeration tank front end is communicated with in the waste disposal plant of the water-in of this aeration tank (1) and denitrogenation dephosphorizing sewage treatment process, the treatment unit water-in of rear end, aeration tank is communicated with in the waste disposal plant of the water outlet of this aeration tank and denitrogenation dephosphorizing sewage treatment process, the bottom, aeration tank is provided with aeration head (8), this aeration head and gas blower (10)) be communicated with, it is characterized in that: the pipeline between aeration head and gas blower is provided with controllable electric valve (9), be provided with adjustable weir plate (8) at the aeration tank water outlet, and being provided with control device, this control device comprises: weir plate drive unit (7), online under meter (3) and online liquidometer (2), PLC controller (5); Described online under meter is located on the water inlet pipe of aeration tank, and online liquidometer is located in the aeration tank, and the weir plate drive unit drives with adjustable weir plate and is connected; Described PLC controller and described online under meter, online liquidometer carry out signal and are connected, and control the control linkage of weir plate lifting with described weir plate drive unit, and with described controllable electric valve control linkage.
2. but the control method of denitrogenation dephosphorizing sewage treatment aeration tank water outlet weir transfer device according to claim 1 is characterized in that may further comprise the steps:
1) starts weir-adjustable control device, in the PLC controller, set the threshold range a of the control liquid level of aeration tank, set the comparison interval time T, set the hydraulic detention time HRT of aeration tank, set gas blower back pressure PSET, the floorage S of aeration tank sets adjustable weir plate single motion amplitude N; The threshold range a of this technique initialization liquid level is 0.01～0.05m, and comparison interval time T 1 is 1～60 minute, and adjustable weir plate single motion amplitude N scope is 1～50mm, and the hydraulic detention time HRT scope of aeration tank is 4～15 hours; Gas blower back pressure PSET scope is 0.04～0.10MPa; Valve single amplitude of accommodation F1 scope is 1-4%; It is 0.0001～0.005MPa that gas blower back pressure single is regulated the F2 scope.
2) utilize online under meter, flow signal Q of collection in per 5 minutes i, unit: m 3/ min calculates required aeration tank liquid level L according to formula (1) Cal:
Figure FSA00000821747600011
Formula (1)
3) from liquidometer with actual liquid level value L iFeed back to the PLC controller, in the PLC controller, actual liquid level value L iWith the required level value L that calculates CalThreshold range, once compare every T;
4) as this actual liquid level value L 1Within computer capacity, namely at L Cal-a≤L i＜L CalBetween+a the value, then system continues operation, but the weir transfer state remains unchanged; As actual liquid level value L i＜L Cal-a starts adjustable weir plate drive unit, but improves weir transfer N mm, increases electrically operated valve aperture F1%, increases gas blower back pressure set value PSET F2MPa, with the minimizing aquifer yield, and increases air demand; As actual liquid level value L i＞=L Cal+ a, but the weir transfer drive unit started, but reduce weir transfer Nmm, reduce electrically operated valve aperture F1%, reduce gas blower back pressure set value PSET F2MPa, with the increasing aquifer yield, and reduce air demand;
5) step of repetition 2～4.
CN2012105333632A 2012-12-12 2012-12-12 Effluent-adjustable weir device with nitrogen and phosphorus removal sewage treatment aeration tank and control method thereof Pending CN103030209A (en)

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Publication number Priority date Publication date Assignee Title
CN103984367A (en) * 2014-05-11 2014-08-13 甘肃金桥给水排水设计与工程(集团)有限公司 Automatic air flotation filtering tank liquid level control system
CN113620411A (en) * 2021-08-31 2021-11-09 哈尔滨天达控制股份有限公司 Constant water level control method and device for biological filter

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103984367A (en) * 2014-05-11 2014-08-13 甘肃金桥给水排水设计与工程(集团)有限公司 Automatic air flotation filtering tank liquid level control system
CN113620411A (en) * 2021-08-31 2021-11-09 哈尔滨天达控制股份有限公司 Constant water level control method and device for biological filter

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Application publication date: 20130410