Productive Experiment On Aerated Biological Filter For Pretreamt The Upstream Water Of Huangpu River

In this paper, productive experiment was conducted on biological ceramisite filter, one of BAFs, to pretreat the upstream water of Huangpu River at the scale of 5000t/d.The results show that :(1)As to the upstream water of Huangpu River, biological ceramisite filter has distinct removal effect on turbidity, Fe, Mn, CODMn and smell, and the removal rates are 40.79%, 55.75%, 54.71%, 18.59% and 59.81% respectively. It also has some effect on the removal of chromaticity and UV254, and the removal rates are 1.48% and 10.08%. The low concentration of NH3-N and NO2-N in the raw water leads to the low removal rate of NH3-N (7.20%) and NO2--N (31.55%) in the biological filter.(2) The effects of biological ceramisite filter under aerated and non-aerated condition were compared. When the concentration of DO is high and that of NH3-N is low in raw water, the removal effect of turbidity, Fe and Mn is better under non-aerated condition and the backwashing period is also extended. The removal rates of COD and chromaticity are almost the same under both conditions. While the removal rates of NH3-N and NO2--N are higher under the aerated condition, which shows that aeration is necessary for the transformation of nutrition and oxygen in the filter even if the DO is enough for the microorganism to grow.(3)The comparison on the pretreatments of biological ceramisite filter and ozone oxidation shows that biological ceramisite filter has better effect on removal of the pollutants than ozone oxidation and it will operate better when the concentration of NH3-N and NO2'-N is high in raw water.(4) The effect of the biological ceramisite filter pretreatment adding the conventional process was studied. The results show that biological pretreatment has good effect on the following conventional process. The dosage of coagulant is decreased and the pollutants in the output water can meet the standard of state.This experiment can provide the pretreatment process scheme and data for the design and operation of water plants, whose raw water is upstream water of Huangpu River or micro-polluted water.