Development and characterization of zeolite biological porous filter for denitrification wastewater treatment by intermittent operation
Zeolite porous biological filter (ZPBF) was prepared using mixed cement, raw zeolite, and aluminum powder through optimization experiment and used as a novel filter medium in biological aerated filter (BAF). The properties of the ZPBF were analyzed by scanning electron microscopy (SEM), and porosimetry. The results show that ZPBF has a large BET-N2(59.54m2/g) and average pore diameter (11.92nm) as well as a high porosity (29.55%). In addition, the uniform and interconnected pores in ZPBF made it suitable for the microbial growth. In order to prove the feasibility of the use of ZPBF in BAF, ZPBF used in the BAF were investigated for city wastewater treatment. Thus, intermittent dynamic experiments were conducted, the intermittent operation cycle included adsorption, biological regeneration, and drip washing ZPBF. Until concentration of NH4+-N was more than 1.5mg/L of effluent standards, water in ZPBF-BAF was firstly emptied. The results show that NH4+-N average removal was 87% and TN average removal was 60% at the blast for 24h and 5d of continuous operation period.The results show that the effluent water could comply with the first grade B in "Discharge Standard of Water Pollutants for Bei Jing city".