A contrast experiment research on rural wastewater treatment efficiency of BAF with zeolite and zeolite-haydite combined packing

Abstract

In order to investigate the effect of biological aerated filter (BAF) with zeolite filler and combined packing, a contrastive experimental study was carried out on zeolite BAF and zeolite-haydite combined packing BAF with the operation parameters such as hydraulic retention time (HRT), temperature and DO keeping constantly throughout the experimental process and the removal efficiency of CODcr, NH4+-N and SS were analysed during the start-up stage and the steady stage. The results showed that on condition that the average temperature was 27°C and DO 6mg/L and HRT 8h, BAF with zeolite filler formed film completely in 30 days, with the removal rate of CODcr, NH4+-N and SS 59.6%, 94.6% and 87%, while zeolite-haydite BAF formed film completely in 25 days, with the removal rate of CODcr, NH4+-N and SS 63.7%, 95.9%, 88.5% respectively, which was better than the former. In summary, BAF with combined zeolite and haydite is superior to BAF with single zeolite for rural wastewater treatment.