CN-121974483-A - Sewage treatment process based on aerobic granular sludge

CN121974483ACN 121974483 ACN121974483 ACN 121974483ACN-121974483-A

Abstract

The invention discloses a sewage treatment process based on aerobic granular sludge, which comprises the steps of introducing sewage to be treated into a reaction tank, enabling the sewage to be in contact with the aerobic granular sludge in the reaction tank, aerating the reaction tank, stopping aerating, discharging supernatant of the reaction tank, retaining the granular sludge, discharging aged sludge appropriately according to the running load of a system, supplementing fresh activated sludge and adjusting water inflow, and performing intelligent period adjustment based on a granular sludge life cycle model. According to the invention, an intelligent cycle adjustment algorithm is constructed by introducing an aerobic granular sludge life cycle model and combining multi-index data such as particle size, sedimentation performance and oxidation-reduction potential, so that the accurate identification and dynamic regulation of the running state of the aerobic granular sludge are realized.

Inventors

ZHU ZONGFEI
YANG DONG
Song Chuanjia

Assignees

南京贝德环保设备制造有限公司

Dates

Publication Date: 20260505
Application Date: 20251231

Claims (10)

1. A sewage treatment process based on aerobic granular sludge is characterized by comprising the following steps: S1, introducing sewage to be treated into a reaction tank, and enabling the sewage to be in contact with aerobic granular sludge in the reaction tank; s2, aerating the reaction tank to enable the outer layer of the granular sludge to form an aerobic zone and the inner layer to form an anoxic zone so as to realize organic matter degradation and nitrogen and phosphorus removal; s3, stopping aeration to enable the granular sludge with good sedimentation performance to be quickly settled and separated from flocculent sludge; S4, discharging supernatant of the reaction tank and retaining granular sludge; s5, discharging aged sludge in proper amount according to the system operation load, supplementing new activated sludge and adjusting water inflow; s6, intelligent period adjustment based on a granular sludge life cycle model comprises the following specific steps: S6.1, collecting related operation parameters; S6.2, calculating a granular sludge life cycle index LCI; s6.3, dynamically adjusting aeration time, sedimentation time and sludge discharge proportion of the SBR according to the life cycle stage.
2. The sewage treatment process based on aerobic granular sludge according to claim 1, wherein the life cycle index LCI is calculated as follows: ; Wherein: 、、 Is a weight coefficient; 、、 respectively the real-time particle size, sedimentation ratio and density of the granular sludge; 、、 the reference value of particle diameter, the reference value of sedimentation ratio and the reference value of density in the mature stage of the particles are respectively.
3. The wastewater treatment process based on aerobic granular sludge according to claim 2, wherein the life cycle model sets different life cycle stages based on LCI, and comprises: growth phase, LCI < first threshold T 1 ; The maturation stage is that T 1 is less than or equal to LCI is less than or equal to a second threshold T 2 ; LCI is more than or equal to T 2 in the aging stage.
4. A sewage treatment process based on aerobic granular sludge according to claim 3, wherein the determination of the lifecycle stage is further combined with a cross determination of any one or more of the following: When the particle diameter of the particles is Greater than the set maximum particle size And when the particle density is reduced to exceed the preset proportion, strongly judging the aging stage; When the sedimentation ratio is Below the sedimentation ratio performance threshold Judging the time intensity as a mature stage; when the volume ratio of the particles is Is increased by a rate exceeding a set value In this case, the growth stage is determined.
5. The process for treating sewage based on aerobic granular sludge according to claim 1, wherein the following cycle adjustment strategy is executed when the life cycle stage is in the growth stage: the aeration time is improved by 10 to 25 percent so as to enhance the shearing force; The sedimentation time is shortened by 10 to 20 percent so as to enhance the selective pressure; the water displacement is properly increased to improve the particle enrichment efficiency.
6. The process for treating sewage based on aerobic granular sludge as claimed in claim 5, wherein the following cycle adjustment strategy is executed when the life cycle stage is in the mature stage: Maintaining the aeration time at a set optimum value ; Performing precipitation according to a set precipitation time to maintain a particle structure; the normal carbon source addition amount is maintained without additionally increasing the selection pressure.
7. The process for treating sewage based on aerobic granular sludge according to claim 6, wherein the following cycle adjustment strategy is executed when the life cycle stage is in the aging stage: The aeration time is reduced by 10 to 20 percent so as to avoid continuous crushing of particles; the sedimentation time is increased by 5 to 15 percent so as to enhance the sedimentation identification of the aged particles; increasing the sludge discharge ratio to discharge aged granular sludge; the carbon source concentration in the feed water is suitably increased to promote nascent particle formation.
8. A sewage treatment process based on aerobic granular sludge as claimed in claim 7 wherein the difference between the current life cycle index and the life cycle index of the previous cycle is determined And performing strategy adjustment, wherein the strategy adjustment is specifically as follows: When (when) Less than a preset threshold Maintaining the current strategy when the current strategy is in the same time; When (when) Less than Enhancing the growth stage adjustment strategy; When (when) Greater than The aging phase adjustment strategy is enhanced.
9. The process for treating sewage based on aerobic granular sludge according to claim 8, wherein the process further comprises the starting of an abnormal recovery period, and the starting triggering conditions of the abnormal recovery period are as follows: particle size of the particles Exceeding the maximum allowable particle size ; Sedimentation ratio A significant increase leads to a deterioration of the sedimentation ratio; Monitoring continuous abnormal fluctuation of oxidation-reduction potential ORP, which indicates cavitation in particles; In the abnormal recovery period, the system reduces aeration time, increases sludge discharge ratio, prolongs settling time, and reduces inflow load.
10. An intelligent sewage treatment control system based on the sewage treatment process based on aerobic granular sludge as claimed in claims 1-9, which is characterized by comprising: the granular sludge parameter acquisition module is used for acquiring 、 Particle parameters such as ρ, VR, ORP, etc.; the life cycle model calculation module is used for calculating LCI and judging the life cycle stage of the particles; The cycle adjusting module is used for automatically adjusting aeration time, sedimentation time, sludge discharge proportion and carbon source addition according to the life cycle stage; the abnormal state processing module is used for executing a recovery strategy when the particle state is abnormal; the control execution unit is used for sending execution instructions to the aeration system, the mud discharging system and the adding system.

Description

Sewage treatment process based on aerobic granular sludge Technical Field The invention relates to the technical field of sewage treatment, in particular to a sewage treatment process based on aerobic granular sludge. Background As a novel sewage biological treatment process which is rapidly developed in recent years, the aerobic granular sludge technology has the advantages of excellent sedimentation performance, high microorganism concentration, strong impact resistance, small occupied area and the like. The current common aerobic granular sludge process is mostly based on a sequencing batch reactor, and the sludge forms a compact granular structure under high selection pressure through a periodic operation mode of water inlet, aeration, precipitation and water discharge. The existing granular sludge operation control is mostly dependent on experience adjustment, such as manual intervention according to sludge concentration, effluent quality or periodic operation effect, and lack of fine management on growth, maturation, expansion, aging and disintegration rules of granular sludge. Particularly in practical engineering, the granular sludge is easily influenced by factors such as water inlet load impact, dissolved oxygen change, internal mass transfer limitation and the like, so that the particle size of the granular sludge is abnormally increased, the sedimentation performance is reduced or the sludge structure is loose, thereby causing system instability and even complete disintegration of the granular sludge. Disclosure of Invention This section is intended to outline some aspects of embodiments of the application and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description of the application and in the title of the application, which may not be used to limit the scope of the application. In order to solve the technical problems, the invention provides the following technical scheme: In a first aspect, the present invention provides a sewage treatment process based on aerobic granular sludge, comprising: S1, introducing sewage to be treated into a reaction tank, and enabling the sewage to be in contact with aerobic granular sludge in the reaction tank; s2, aerating the reaction tank to enable the outer layer of the granular sludge to form an aerobic zone and the inner layer to form an anoxic zone so as to realize organic matter degradation and nitrogen and phosphorus removal; s3, stopping aeration to enable the granular sludge with good sedimentation performance to be quickly settled and separated from flocculent sludge; S4, discharging supernatant of the reaction tank and retaining granular sludge; s5, discharging aged sludge in proper amount according to the system operation load, supplementing new activated sludge and adjusting water inflow; s6, intelligent period adjustment based on a granular sludge life cycle model comprises the following specific steps: S6.1, collecting related operation parameters; S6.2, calculating a granular sludge life cycle index LCI; s6.3, dynamically adjusting aeration time, sedimentation time and sludge discharge proportion of the SBR according to the life cycle stage. As a preferable scheme of the sewage treatment process based on aerobic granular sludge, the life cycle index LCI is calculated as follows: ; Wherein: 、、 Is a weight coefficient; 、、 respectively the real-time particle size, sedimentation ratio and density of the granular sludge; 、、 the reference value of particle diameter, the reference value of sedimentation ratio and the reference value of density in the mature stage of the particles are respectively. As a preferable scheme of the sewage treatment process based on aerobic granular sludge, the life cycle model sets different life cycle stages based on LCI and comprises the following steps: growth phase, LCI < first threshold T 1; The maturation stage is that T 1 is less than or equal to LCI is less than or equal to a second threshold T 2; LCI is more than or equal to T 2 in the aging stage. As a preferable scheme of the sewage treatment process based on aerobic granular sludge, the invention further comprises the following steps of carrying out cross judgment according to the judgment of the life cycle stage: When the particle diameter of the particles is Greater than the set maximum particle sizeAnd when the particle density is reduced to exceed the preset proportion, strongly judging the aging stage; When the sedimentation ratio is Below the sedimentation ratio performance thresholdJudging the time intensity as a mature stage; when the volume ratio of the particles is Is increased by a rate exceeding a set valueIn this case, the growth stage is determined. As a preferable scheme of the sewage treatment process based on aerobic granular sludge, the invention comprises the following cycle adjustment strategy is executed when the life cycle stage is in a growth stage: the ae