Feasibility study of powdered activated carbon membrane bioreactor (PAC-MBR) for source-separated urine treatment: A comparison with MBR

Abstract

Micropollutants (MPs) such as pharmaceuticals and personal care products are a group of emerging environmental contaminants, which are structurally complex and can cause adverse physiological effects on human health at low concentration. This study demonstrated that a hybrid process of powdered activated carbon and microfiltration membrane bioreactor (PAC-MBR) could be utilized for efficient removal of metronidazole, acetaminophen, naproxen, ibuprofen, carbamazepine, estriol (> 99 %) from source-separated urine via physical adsorption and biodegradation in a single step, without compromising the operating system stability. PAC addition to MBR improved 5 % of nitrification performance in terms of ammonia to nitrate conversion rate. Further, it improved organic removal efficiency from 88.6 ± 2.9 % to 96.0 ± 1.2 %, promoted rapid biomass growth, increased sludge floc size growth by 17 % and reduced membrane fouling propensities. This study showed the production of a micropollutant-free fertiliser from source-separated urine achieving a complete nutrient recovery in a single stage MBR system.