Preparation of ultra-lightweight sludge ceramics (ULSC) and application for pharmaceutical advanced wastewater treatment in a biological aerobic filter (BAF)

Novel media-ultra-lightweight sludge ceramics (ULSC) employed in an upflow lab-scale biological aerobic filter (BAF) were investigated for pharmaceutical advanced wastewater treatment. The influences of the volume ratio of pharmaceutical wastewater to domestic wastewater (PW/DW), hydraulic retention time (HRT) and air-liquid ratio (A/L) on chemical oxygen demand (CODCr) and ammonium (NH4+-N) of the effluent were investigated. When PW/DW of 4:1, HRT of 6 h, and A/L of 5:1 were applied, the mean effluent concentration of NH4+-N was 6.2 mg L−1, and the maximum CODCr concentration in the effluent was 96 mg L−1. Both NH4+-N and CODCr did not exceed the limits of the national discharge standards (NH4+-N ⩽ 15 mg L−1, CODCr ⩽ 100 mg L−1). In addition, the BAF system showed a strong capacity of further removal from NH4+-N of the effluent.