The Study On Submerged MBR For Nitrogen Removal

The submerged membrane bioreactor is a new wastewater treatment technology. It has the characteristics of lower energy consumption,small space requirement,simple treatment process,easier operation and more convenient maintenance.Applying the submerged membrane bioreactor on the treatment of sewage can improve effluent quality to meet more and more strict integrated wastewater discharge standard.Efficiency and economy has become the hot point on the sewage treatment at present. The effect of the hydraulic retention (HRT), DO, on the removal efficiency of contaminations has been studied in this experimentation. when the influent CODCr was in the range of 200-300mg/L, the total nitrogen was 24-35mg/L, the hydraulic retention(HRT) was 6h, 8h, 12h, NH3-N removal were 38.7%, 58.9%, 73.6% respectively. Based on the theories of biological nitrogen, the nitrification and denitrification process were forced to occur in the submerged membrane bioreactor through controlling levels of dissolved oxygen between 0-4mg/L. when the hydraulic retention(HRT) was 6h, 8h, 12h, TN removal were 33.6%,45.1%,54.3% respectively. The pH values in the submerged membrane bioreactor varied between 7.0-7.8.The time interval for ultrasonic treatment could be set at 24h to enhance biological activity through the study of the ultrasonic effect change with time.The experiments with ultrasonic at diferent power intensities showed that ultrasonic at a power intensity of 0.3W/cm2 could enhance biological activity significantly.The ultrasonic effect was studied through nitrogen removal the contrast experiments between the reactors with and without ultrasonic. Parallel experiments showed that ultrasonic at a power intensity of 0.3W/cm~2 could control membrane pollution to some level.