Experimental study on bio-contact oxidation method start-up at low temperature by two-stage method

Under the condition of 3 similar to 6 degrees C water temperature, two-stage bio-membrane treatment is adopted to conduct the research of bio-membrane start-up experiment which uses bio-contact oxidation method to treat municipal sewage. The test ascertained the operating parameters for two stages respectively, namely the DO value of the first stage was 5-7mg/L,under which 20 days of intermittent water inflow was kept and hydraulic retention time was controlled in 24 hours;The second phase was under the DO value of 3 similar to 5mg/L, providing the continuous water inflow for 16 days and HRT within 12 hours. The results showed that after 36 days' cultivation, the removal of COD, NH(4)(+) - N and turbidity could achieve 72%, 5%, 81% respectively. During the test, no carbon source was added, so did reflow, what's more, the operation was simple while the start-up time was short.Low temperature had small impact on the removal of COD and turbidity, but considerable influence on NH(4)(+) -N.When the temperature was below 5 degrees C, the system had no obvious effect on the removal of NH(4)(+) - N N. Some factors will do harm to the system at first,such as water quality fluctuation and air bubbles scouring.