Study On The Performance Of Up Anaerobic Sludge Blanket (UASB) Reactor Treatinglow Sthength Organic Wastewater At Ambient Temperatures

The municipal wastewater increased with each passing day, and the aerobic processes took high investment and operational cost. The high rate Up Anaerobic Sludge Blanket (UASB) reactor that was power saving, low maintenances and operational costs was used in experiment to treat low strength wastewater to study the possibility of treating municipal wastewater with anaerobic processes. During 374 days experimental period, the performance of the reactor was studied through changing the influence factors including the kind of substrates, concentration, hydraulic loading rate, hydraulic retention time, etc, moreover, the kinetics of anaerobic biological treating low strength wastewater was analyzed.Through the results of test we could conclude as follows .The achieving designed organic loading rate and stable removal efficiency were the signs of successful start-up of an UASB reactor rather than the forming of the granular sludge.K2 can be used as a parameter to evaluate start-up of the reactor. Temperature fluctuations can't influence removal efficiency remarkably when the temperature was higher than 15 Long hydraulic retention time was not sufficient to achieve high organic removal efficiency. The optimal hydraulic retention time was about 6 hours. It was very important to maintain enough acid-alkaline buffer capacity in the reactors at ambient temperatures.In the experiment of UASB reactor treating raw domestic sewage, the effluence CODcr was below lOOmg/L without additional alkaline, when the ambient temperature ranged from 20to 30, the influent CODcr ranged from 68mg/L to 643mg/L, and the hydraulic retention time ranged from 4.5h to 12.8h.