کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6367548 | 1316843 | 2013 | 8 صفحه PDF | دانلود رایگان |
- Anaerobic MBR treatment of settled sewage is possible under ambient temperatures.
- Granular AnMBR enables lower energy membrane operation than flocculent AnMBRs.
- Gas sparge operated for only 10% of the time with the granular based AnMBR.
The treatment efficiency and membrane performance of a granular and suspended growth anaerobic membrane bioreactor (G-AnMBR and AnMBR respectively) were compared and evaluated. Both anaerobic MBRs were operated in parallel during 250 days with low strength wastewater and under UK weather conditions. Both systems presented COD and BOD removal efficiencies of 80-95% and >90% respectively. Effluent BOD remained between 5 and 15 mgBOD Lâ1 through the experimental period while effluent COD increased from 25 mg Lâ1 to 75 mg Lâ1 as temperature decreased from 25 °C to 10 °C respectively indicating the production of non biodegradable organics at lower temperatures. Although similar levels of low molecular weight organics were present in the sludge supernatant, recycling of the mixed liquor from the membrane tank to the bioreactor at a low upflow velocity enhanced interception of solids in the sludge bed of the G-AnMBR limiting the solid and colloidal load to the membrane as compared to the suspended system. Results from flux step test showed that critical flux increased from 4 to 13 L mâ2 hâ1 and from 3 to 5 L mâ2 hâ1 with gas sparging intensities varying from 0.007 m sâ1 to 0.041. Additional long term trials in which the effect of gas sparging rate and backwashing efficiency were assessed confirmed the lower fouling propensity of the G-AnMBR.
177
Journal: Water Research - Volume 47, Issue 14, 15 September 2013, Pages 4853-4860