摘要
Abstract
Objective] The aim was to study effects of backflush on sewage land aerobic biological filtration system .[ Method] In the flow of 1.4 m3/d and aeration 1.8 m3/h, the water test conditions to primary sedimentation tank effluent of Haibohe wastewater treatment plant, bio-film had been completed for 19 days in the system, the effluent COD removal rate reached 80%.Under the condition that in air impact strength 13.9 L/(m2・s), water impact strength 0.1 L/(m2・s), we studied the removal efficiency of COD and NH4+-N of the system with dif-ferent backflushing interval (4, 8 d) and backflushing time(1, 2, 4, 6 min).[Result] The results showed that: under the conditions that backflushing interval 4 d and backflushing time(1, 2, 4 min), the biofilm was less damged, the effluent average COD was 76 mg/L and NH4+-N was lower than 5 mg/L, the system could run for 28 days.Under the conditions that backflushing interval 8 d and (1, 2, 4 min), the effluent average COD was 93.0 mg/L and NH4+-N was 6.8 mg/L, and the effluent was slightly higher than that of the 4 day period; in back-flushing time 6 min, the system biofilm certain degree of damage, the effluent COD and NH4+-N increased to 130.8 mg/L and 14.1 mg/L, it should take 4 days to recover the system.[ Conclusion] 4 min backflush is recommended for similar system 4-8 d, 6 min backflush should be carried out if there is a blockage.关键词
污水土地处理/好氧生物过滤/反冲洗周期/反冲洗时间Key words
Wastewater land treatment/Aerobic biological filtration/Backflushing interval/Backflushing time分类
农业科技
