Treatment of pharmaceutical wastewater containing β-lactams antibiotics by a pilot-scale anaerobic membrane bioreactor (AnMBR)

Abstract

A 180 L anaerobic membrane bioreactor (AnMBR) was operated for 253 days to treat real pharmaceutical wastewater, which mainly composed of β-lactams antibiotics (BLAs) including amoxicillin, ceftriaxone, cefoperazone and ampicillin. The operation was divided into three stages with hydraulic retention time (HRT) of 48 h, 36 h and 24 h, respectively, the corresponding average organic loading rates (OLRs) and antibiotics loading rates (ALRs) increased from 2.37 ± 0.28 to 4.46 ± 0.87 kg-COD·m−3·d−1, and from 19.06 ± 0.67 to 37.91 ± 3.57 g-BLAs·m−3·d−1, respectively. The highest removal efficiencies of amoxicillin, ceftriaxone, cefoperazone and ampicillin were 73.2 ± 4.3%, 47.7 ± 2.2%, 79.4 ± 4.1% and 34.6 ± 3.3%, respectively. The obtained total COD removal efficiency was as high as 94.0% and accompanied with VFA accumulation (249 ± 25 to 375 ± 61 mg·L−1) as well as biogas generation (0.195 ± 0.017 to 0.291 ± 0.032 L·gCODremoval−1), >66% of which was methane (0.135 ± 0.011 to 0.196 ± 0.021 L·gCODremoval−1). Moreover, basing on the back propagation neural network (BPNN) theory, the mathematical models were developed and well calibrated for simulating the AnMBR performance in the biodegradation of COD and antibiotics.