CN-121974491-A - MSBR (multi-stage dissolved oxygen) limit denitrification method based on intelligent regulation and control of multistage dissolved oxygen

CN121974491ACN 121974491 ACN121974491 ACN 121974491ACN-121974491-A

Abstract

The invention relates to the technical field of sewage treatment, in particular to an MSBR (multi-stage dissolved oxygen) limit denitrification method based on intelligent regulation and control of multi-stage dissolved oxygen, which comprises the steps of arranging physical partitions in an MSBR main aeration aerobic unit along the water flow direction, constructing a plurality of independent aeration areas, and forming a 'high-medium-low' dissolved oxygen concentration space gradient field through partition regulation and control; combining real-time monitoring data, constructing a dissolved oxygen trend prediction model, dynamically optimizing a dissolved oxygen concentration gradient field form and a carbon source multipoint differential dosing strategy according to a water inlet C/N ratio, and simultaneously constructing a grading impact judgment and quick response mechanism. The invention realizes the coupling of various denitrification paths through the cooperation of physical configuration and intelligent algorithm, breaks through the denitrification limit of the traditional activated sludge process, realizes that the total nitrogen of MSBR effluent is as low as 1.5mg/L and the daily average value is less than 4mg/L, obviously reduces the energy consumption and the medicine consumption, enhances the impact resistance of the system and provides an innovative solution for the deep denitrification of sewage.

Inventors

WANG WENMING
LIU XIAO
SONG FENGMING
HE BO
WANG DONGBO
SHEN LEI
YANG QILIANG
HE JIANWEI
GU WEI
LAI XU

Assignees

湖南先导洋湖再生水有限公司
湖南大学
可事托环保设备（上海）有限公司

Dates

Publication Date: 20260505
Application Date: 20260204

Claims (10)

1. An MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation is characterized by comprising the following steps: Step S1, a main aeration aerobic unit of an MSBR reaction tank is physically separated along the water flow direction and is divided into a plurality of independent partition aeration units, and each partition aeration unit is provided with an independent aeration pipeline and a control valve; S2, based on the water quality characteristics of the inlet water of the MSBR tank, performing independent aeration control on each subarea aeration unit so as to actively form and maintain a dissolved oxygen concentration space gradient field which is continuously changed in the water flow direction in the main aeration aerobic unit, thereby forming a multi-section dissolved oxygen environment in the main aeration aerobic unit; Step S3, real-time monitoring water quality parameters, water quantity and water temperature in the MSBR reaction tank, dissolved oxygen concentration and sludge concentration of each partition of the main aeration aerobic unit and microbial community characteristics to form a multisource monitoring data set; Step S4, dynamically adjusting aeration intensity, sludge reflux ratio, sludge concentration, sludge discharge strategy and carbon source adding strategy based on the obtained multisource monitoring data set so as to cooperatively regulate and control short-range nitrification and denitrification, whole-course nitrification and denitrification and synchronous nitrification and denitrification paths; and S5, enabling the sewage to sequentially pass through the inherent multistage reaction environment of the MSBR tank, and realizing deep denitrification under the synergistic effect of the multistage dissolved oxygen gradient environment in the main aeration aerobic unit and the intelligent control algorithm.
2. The MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 1, wherein in the step S1, the physical partition is a diversion partition wall provided with regular water passing holes for guiding water flow sequentially through each partition aeration unit to inhibit mixing of sequential water flow.
3. The MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 1, wherein in the step S4, comprising: Step S41, sequentially obtaining the dissolved oxygen concentration of each partition along the water inflow direction, judging and dynamically adjusting the aeration intensity of each partition so as to stabilize the dissolved oxygen space gradient; step S42, a dissolved oxygen trend prediction model is constructed based on historical and real-time data, and short-term impact risk judgment is carried out based on the instantaneous change rate of the inflow water flow and the pollutant concentration monitored in real time; step S43, based on the real-time influent carbon-nitrogen ratio and pollutant load, cooperatively optimizing the morphological parameters of the high-medium-low gradient field, and simultaneously, based on the carbon source demand of the dominant denitrification path and the real-time feedback of the effluent nitrate nitrogen concentration, generating and executing an on-demand intermittent dosing strategy of a carbon source in a first anoxic unit and/or a second anoxic unit, and cooperatively regulating and controlling a short-range nitrification denitrification path, a full-range nitrification denitrification path and a synchronous nitrification denitrification path; and S44, adjusting the sludge reflux ratio, the system sludge concentration and the sludge discharge strategy in a linkage way according to the water temperature change, the total nitrogen concentration real-time feedback of the effluent and the microbial community characteristics.
4. The MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 3, wherein in the step S42, the short-term impact risk judgment comprises: If the instantaneous change rate of the inflow water flow or the key pollutant concentration exceeds a first preset threshold value, judging that the water inflow or the key pollutant concentration is light impact, and immediately improving the aeration intensity of each subarea aeration unit according to a preset proportion; If the instantaneous change rate of the inflow water flow or the key pollutant concentration exceeds a second preset threshold value, the heavy impact is judged, and the control algorithm is synchronously switched to a higher-frequency sampling and adjusting period while the aeration intensity is improved.
5. The MSBR limiting denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 3, wherein in the step S42, the dissolved oxygen trend prediction model is constructed based on theoretical oxygen consumption and adaptive correction factors, wherein, The theoretical oxygen consumption is determined according to the carbon oxidation oxygen demand, the nitrification oxygen demand, the denitrification recovered oxygen equivalent and the hydraulic impact comprehensive correction factor; the adaptive correction factor is calculated based on the deviation of the predicted total oxygen demand OTR of the system from the actual oxygen demand OTRa of the system.
6. The MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 3, wherein in the step S43, comprising: When the chemical oxygen demand of the inflow water is lower than a third threshold value, narrowing the space ratio of the high oxygen area, and remarkably expanding the space ratio of the low oxygen area and the medium oxygen area to form a wide anoxic/aerobic alternative microenvironment in an aerobic unit, strengthen synchronous nitrification and denitrification, and provide an advantageous environment for short-range nitrification and denitrification; When the chemical oxygen demand of the inflow water is between the third threshold value and the fourth threshold value, the space duty ratios of the three areas of high, medium and low with obvious difference and balance are maintained, so that the partition parallelism and the function complementation of the shortcut nitrification and denitrification, the whole-course nitrification and the synchronous nitrification and denitrification are realized in space, and the efficient coupling of a plurality of denitrification mechanisms is realized through the optimization of the gradient field morphology; When the chemical oxygen demand of the inlet water is higher than the fourth threshold value, the high oxygen area ratio is enlarged, and the low oxygen area ratio is compressed at the same time, so that the complete nitrification capacity under high organic load is ensured, and meanwhile, strict denitrification conditions are created for the subsequent anoxic units, and the efficient operation of the whole nitrification and denitrification path is ensured.
7. The MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 3, wherein in the step S44, comprising: Step S441, water temperature adaptive regulation and control, namely when the water temperature is monitored to be continuously lower than a third threshold value, starting a winter operation mode, improving the sludge concentration of the system, and correspondingly increasing the total addition amount of the carbon source according to the requirement; step S442, effluent feedback closed-loop regulation, namely, based on a real-time measurement value of total nitrogen concentration of effluent, adjusting the overall dissolved oxygen level of the main aeration aerobic unit and the total addition amount of an external carbon source in a closed loop manner; and S443, optimizing and controlling sludge age, namely dynamically adjusting sludge discharge amount based on the microbial community characteristic analysis result to optimize the sludge age of the system and maintain the dominant position of the functional flora.
8. The MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 7, further comprising adjusting a dissolved oxygen control range of each partition in the main aeration aerobic unit in the winter operation mode.
9. The MSBR limiting denitrification method based on multistage dissolved oxygen intelligent regulation according to claim 5, wherein the hydraulic impact comprehensive correction factor is determined according to the product of the flow load impact factor and the flow rate/mixing efficiency factor, wherein, The flow load impact factor is determined according to the deviation between the current flow and the recent average flow; The flow rate/mixing efficiency factor is determined based on the actual flow rate or the actual hydraulic residence time in the main aeration unit.
10. A sewage treatment system employing the multistage dissolved oxygen intelligent regulation-based limiting denitrification method according to any one of claims 1 to 9, characterized by comprising: the main aeration aerobic unit is a rectangular tank body, a physical partition is arranged in the tank along the length direction and is divided into a plurality of independent partition aeration units, and each partition aeration unit is provided with an independent aeration pipeline and a control valve; The carbon source multipoint adding unit comprises at least one first adding device arranged on the first anoxic unit or the second anoxic unit, and a second adding device arranged on the first anoxic/aerobic unit or the second anoxic/aerobic unit which is arranged on the downstream of the main aeration aerobic unit outlet water; The multi-parameter on-line monitoring unit comprises an on-line analyzer for monitoring the quality of the inflow water, a dissolved oxygen sensor and a sludge concentration meter which are arranged in each partition of the main aeration aerobic unit; The intelligent control unit is in communication connection with the multi-parameter on-line monitoring unit, each air flow regulating valve of the partitioned main aeration aerobic unit, the carbon source multi-point adding unit and the sludge reflux and discharge device, and is used for executing the limit denitrification method based on the intelligent regulation and control of the multistage and multistage dissolved oxygen, which is described in any one of claims 1-9.

Description

MSBR (multi-stage dissolved oxygen) limit denitrification method based on intelligent regulation and control of multistage dissolved oxygen Technical Field The invention relates to the technical field of sewage treatment, in particular to an MSBR (multi-stage dissolved oxygen) limit denitrification method based on intelligent regulation and control of multistage dissolved oxygen. Background Nitrogen is one of the important reasons for inducing eutrophication of water, and it is important to improve the denitrification efficiency of sewage plants. At present, the advanced excavation of the denitrification potential of the original biological treatment process, the addition of the advanced treatment process of the denitrification biological filter, the development of the short-range denitrification coupling anaerobic ammonia oxidation process, the development of the aerobic granular sludge process and the like are widely studied sewage biological denitrification technologies. Considering the synergistic requirement of pollution reduction and carbon reduction and the maturity of process application, the denitrification potential of the original biological treatment process is deeply excavated, and the technology scheme is still the most practical at present. A large number of researches and engineering cases show that the improved sequencing batch intermittent reactor (MSBR) has the advantages of small occupied area, high utilization rate of the carbon source of the inlet water, good denitrification and dephosphorization effects and the like, and is an advanced biological treatment process applicable to a sewage plant with high emission standard, so that the iterative development of MSBR biological denitrification towards the high efficiency, low carbonization and intelligent direction is necessary to be realized through fine design and intelligent regulation. At present, MSBR technology is mainly controlled and managed on site through technician experience, for example, the concentration of the integral Dissolved Oxygen (DO) of a main aeration aerobic unit is controlled according to 2-4 mg/L of traditional experience, so that a large amount of dissolved oxygen is brought to sludge mixed liquor which flows back to an anoxic unit, the anoxic environment of the anoxic unit is influenced, part of influent organic carbon sources are consumed, the aeration energy consumption of a blower and the addition of external carbon sources are increased, and the main aeration aerobic unit is not beneficial to forming macro environment and micro environment (anoxic state in zoogloea) of short-distance nitrification and synchronous nitrification and denitrification. Therefore, the existing artificial experience regulation and control mode of MSBR has the defects of high energy consumption, high medicine consumption, incapability of actively guiding the cooperative coupling of various denitrification paths, lack of intelligent regulation and control and the like, and is difficult to realize the limit denitrification effect. Disclosure of Invention Therefore, the invention provides an MSBR (multi-stage dissolved oxygen) limit denitrification method based on intelligent regulation and control, which is used for solving the problems that in the prior art, a model is disjointed from an MSBR process structure, the implementation cost is high due to dependence on complex parameters, the synergy of a plurality of denitrification paths cannot be actively guided, and the foundation for realizing deep energy conservation through a physical structure is lacking. In order to achieve the above purpose, the invention provides an MSBR limit denitrification method based on multistage dissolved oxygen intelligent regulation, which comprises the following steps: Step S1, a main aeration aerobic unit of an MSBR reaction tank is physically separated along the water flow direction and is divided into a plurality of independent partition aeration units, and each partition aeration unit is provided with an independent aeration pipeline and a control valve; S2, based on the water quality characteristics of the inlet water of the MSBR tank, performing independent aeration control on each subarea aeration unit so as to actively form and maintain a dissolved oxygen concentration space gradient field which is continuously changed in the water flow direction in the main aeration aerobic unit, thereby forming a multi-section dissolved oxygen environment in the main aeration aerobic unit; Step S3, real-time monitoring water quality parameters, water quantity and water temperature in the MSBR reaction tank, dissolved oxygen concentration and sludge concentration of each partition of the main aeration aerobic unit and microbial community characteristics to form a multisource monitoring data set; Step S4, based on the obtained multisource monitoring data set, dynamically adjusting aeration intensity, sludge reflux ratio, sludge concentration, sludge discharge s