Performance comparison of aerobic filter and deep bed equal coarse ceramic filter

To improve the removal efficiency of organics and ammonia nitrogen by filtration in advanced wastewater treatment process, air was supplied to filter bed via backwashing air distribution pipes during filtration. This kind of filter was called aerobic filter (AF) in this article. Contrast tests were done between AF and deep bed equal coarse ceramic filter (DF) with the same influent, which was the secondary effluent of a municipal wastewater treatment plant in north China. Results showed that, AF had high flexibility for the quality variation of influent. Chemical oxygen demand, ammonia nitrogen, turbidity and suspended solids in effluent of AF were lower than those in effluent of DF with the same influent during the most of test time. In contrast with DF, the worse the influent, the higher performance of AF was observed. Besides, the initial headloss of AF was higher than that of GF and the headloss increasing rate was higher too. Most headloss was distributed at the top bed for GF while the headloss of AF was distributed evenly along the bed profile. At the same operation condition, AF consumed shorter run time than GF.