Optimized chemical dosing method of membrane subassembly backwashing of membrane bioreactor

• Main Authors: TANG LI'NA, LIU MENG, REN YANZHEN, YANG BIN
• Format: Patent
• Language: English
• Published: 09.12.2015
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATERTREATMENT OR WASTE MANAGEMENT; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The invention discloses an optimized chemical dosing method of membrane subassembly backwashing of a membrane bioreactor. Operation of the membrane bioreactor is carried out at a constant water yield. The optimized chemical dosing method comprises following steps: a current membrane flux change rate dJ/dt of a membrane subassembly of the membrane bioreactor in a continuous water production period is calculated; a membrane flux change rate reference value mu is set, and the specific ratio (R) of the current membrane flux change rate dJ/dt of the membrane subassembly of the membrane bioreactor in the continuous water production period to the membrane flux change rate reference value mu is calculated, R=(dJ/dt)/mu; the value of R is compared with a threshold value, if the value of R is in a threshold value range, chemical dosing amount of membrane subassembly backwashing of the membrane bioreactor is adjusted, otherwise, the chemical dosing amount of membrane subassembly backwashing of the membrane bioreactor is not adjusted. According to the optimized chemical dosing method, the chemical dosing amount is adjusted based on practical situations of membrane contamination so as to eliminate MBR membrane pollution at a forming stage, avoiding collaborative deterioration effect caused because of delayed membrane pollution control, saving time, and prolonging service life of the membrane subassembly.