Effect of sludge recirculation on removal of antibiotics in two-stage membrane bioreactor (MBR) treating livestock waste
- PDF / 2,029,485 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 53 Downloads / 174 Views
RESEARCH ARTICLE
Effect of sludge recirculation on removal of antibiotics in two-stage membrane bioreactor (MBR) treating livestock wastewater Rathborey Chan 1 & Chart Chiemchaisri 1
&
Wilai Chiemchaisri 1
Received: 6 January 2020 / Accepted: 15 October 2020 # Springer Nature Switzerland AG 2020
Abstract Two-stage MBR consisting of anaerobic and aerobic reactors was operated at total hydraulic retention time (HRT) of 48 h for the treatment of livestock wastewater containing antibiotics, i.e. amoxicillin (AMX), tiamulin (TIA), and chlortetracycline (CTC), under the (1st) absence and (2nd) presence of sludge recirculation between the reactors. During the operation with sludge recirculation, the removals of organic and nitrogen were enhanced. Meanwhile, the removals of TIA and CTC were found to decrease by 9% and 20% in the aerobic reactor but increased by 5% to 7% in the anaerobic reactor due to the relocation of biomass from the aerobic to the anaerobic reactor. A high degree of AMX biodegradation under both anaerobic and aerobic conditions and partial biodegradation of TIA and CTC under aerobic conditions were confirmed in batch experiments. Moreover, the effect of sludge recirculation on biomass and pollutant removal efficiencies in the 2-stage MBR was revealed using microbial community analyses. Membrane filtration also helped to retain the adsorbed antibiotics associated with small colloidal particles in the system. Keywords Antibiotics . Livestock wastewater . MBR . Sludge recirculation . SRT
Introduction Improper and excessive use of antibiotics in the livestock farm has raised concern as one of the major environmental issues worldwide [1, 2]. The residual antibiotics released together with livestock wastes and wastewater could potentially be contaminated in the environment through intentionally discharging from farms with or without proper treatment, unintentional spills or release through the overflow from water retention ponds in the farms during rainy seasons. The previous studies [3–5] investigated that the relevance antibiotics used in farms were detected in different water samples, including municipal wastewater, canal water, river water, and even groundwater. Their residual compounds ultimately result in
Electronic supplementary material The online version of this article (https://doi.org/10.1007/s40201-020-00571-z) contains supplementary material, which is available to authorized users. * Chart Chiemchaisri [email protected] 1
Department of Environmental Engineering, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand
the development of antibiotic-resistant pathogens. Even releases of pathogenic bacteria containing integrons, capable of capturing and expressing arrays of genes, may conceivably accelerate the development of resistance by providing increased possibilities to probe the environmental resistance for novel resistance genes not yet encountered in the clinic [6]. Researches by Managaki et al. [7] and Hoa et al. [8] reported that macrolides, sulfonamides, and trimetho
Data Loading...
