Study On The Treatment Of PVA Desizing Wastewater By Up-flow Aerated Biological Activated Carbon Filter (UABACF)

PVA desizing wastewater is difficult to be biodegraded with high viscosity. How to treat the wastewater more efficiently with lower cost is the problem that companies and researchers are facing now. This subject uses a upflow biological aerated filter (UABACF) to degrade PVA desizing wastewater. The researches include operating characteristics and microbial characteristics. The results can provide a theoretical reference and data to support exploring effective biological treatment of PVA desizing wastewater.The main results of the research are as follows:1) By adjusting the two factors of gas-water ratio and hydraulic loading, the optimal process parameters were obtained:gas-water ratio was3, hydraulic loading was0.076m3/(m2·h), HRT was24h, pH was at7.0to8.0. Under the condition of optimal parameter, the average removal rate of PVA, COD and turbidity were64.36%、87.07%and80.25%, and the corresponding effluent average of PVA, COD and turbidity were separately29.1mg/L、63.06mg/L and0.81NTU.2) By adjusting the gas-water ratio and hydraulic loading, the effect of filter height on organics and turbidity in the filter was studied. The results showed that main pollutant removal area is under1.3m of the filter column in the condition of gas-water ratio of3and hydraulic loading of0.076m3m2·h,3) By detecting the biomass and bioactivity in different hight of the UABACF, the microbial properties which using activated carbon as carrier were studied. By phospholipids method, the content of phospholipids contained in the column was declined largest at1.3m along the filter. The degradation of pollution and biomass were in closely relationship. Taking the TTC-dehydrogenase activity as bioactivity index, the results showed that the bioactivity of activated carbon decreased as the height of filer increased. At the1.2m of filter the reduction of bioactivity tended to gentle and it reduced to the minimum at1.5m. The microbial film still has certain biological activity on the upper filter.4) The removal of PVA in UABACF can be divided into biological adsorption and biodegradation. The results showed that57.8%of PVA was adsorbed by microorganism, only19.1%of PVA was biodegraded and23.1%of PVA still remained in the effluent. The filter with high microbe members couldn’t biodegrade PVA efficiently. PVA adsorption mainly occurred in the area between0.3m to0.7m height and53.8%of adsorbed PVA accumulated in this zone.