Remediation of Pharmaceutical-Wastecontaining Municipal Wastewater Using a Novel Nonthermal Plasma Reactor

Abstract

Efficient treatment of contaminants in wastewater before discharging into water bodies is crucial for curtailing environmental and health challenges. In this study, a dielectric barrier discharge (DBD) reactor, operated in a continuous mode, was evaluated for the removal of chemical oxidation demand (COD) and pharmaceutical contaminants (erythromycin and ciprofloxacin) from municipal wastewater. Real wastewater samples of varying COD strengths (of about 350 mg/L; 250 mg/L and 90 mg/L) were treated using the nonthermal plasma (NTP) reactor. The DBD plasma reactor used in this study generated ozone via a locally manufactured High Voltage Alternating Current Power Supply Unit (HVAC PSU, 40 kV-15 mA). A high-performance liquid chromatograph was used to analyse the pharmaceutical contaminants before and after the treatment. The investigation shows 55%, 53%, 51% COD removal from the 350 mg/L, 250 mg/L and 90 mg/L samples, respectively, after 15 minutes of time-on-stream treatment. The results of the degradation of the pharmaceutical recalcitrant contaminants in the wastewater reveal about 65% removal efficacy for ciprofloxacin and 60% for erythromycin after treatment time of 10 minutes. The removal efficacy increased to 72% for ciprofloxacin and 70% for erythromycin at 15 minutes. The obtained results underpin the potential of the newly designed NTP reactor as a tertiary treatment unit.