The Study Of A/O/DMBR For Wastewater Treatment

Nitrogen is one of the most important materials which induce water body eutrophication and contamination. Several traditional wastewater treatment technologies are low in nitrogen removal efficiency. The concentration of nitrogen is so high that the effluent unable to reach outlet water quality standard, it also do harm to our health and influencethe development of economy. How to remove nitrogen rationally is a hard difficult which waste-water treatment researchers must conquer now days.An anoxic/oxic/dynamic membrane bioreactor (A/O/DMBR) was chosen to treat the low C/N ratio wastewater in this experiment. Hydraulic retention time was changed one by one and under each changed congdition, the treat eficiency is studied and I selected the hydraulic retention time was 12h. The experiment showed that a high removal rate of COD could be seen using A/O/DMBR to treat septic-tank wastewater. But the removal effect of nitrification is not good because of the low C/N ratio. So, the removal effecicency was studied under the different C/N ratio condition through adding the carbon source into the wastewater. The result showed that: the removal rates of COD,NH3-N and TN were all increased as the C/N ratio increased, this indicates that increasing the carbon source is benifical to the removel of the organic and nitrification. Simultaneously because of the High-effect entrapment ability of the dynamic membrane, this system has a good removal effect of the turbidity. The research of anti-impact on anoxic/oxic/dynamic membrane bioreactor showed that this system has the stronger anti-impact and good stability. During the experimental period the biological reactor sludge density,SV30,SVI which changed along with the running time were also inspected, and the values of nitrification rate and denitrification rate under two tempreture cindition were examed. The research of the pollutant removal contribution of dynamic membrane indicated that dynamic membrane has the removal rate of COD about 10%, but it has no removal rate of NH3-N. In the experiment using running water flushing when membrane pollution was serious, then it can restore original membrane flux.