EFFECTIVENESS OF DIFFERENT WASTEWATER TREATMENT PROCESSES FOR REMOVING EMERGING CONTAMINANTS IN KADUNA METROPOLIS

Abstract

This study assessed the effectiveness of different wastewater treatment processes for removing emerging contaminants in Kaduna metropolis. Wastewater samples were collected from four different sources: domestic, industrial, agricultural, and pharmaceutical. Four treatment processes: coagulation-flocculation, adsorption, ultrafiltration, and nanofiltration were used to remove the target contaminants. The presence of these contaminants before and after treatment was analysed using gas chromatography-mass spectrometry (PAH method) at the University of Ilorin's Chemical Engineering laboratory. The results identified eighteen emerging contaminants: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[c]phenanthrene, benz[a]anthracene, chrysene, benzo[k]fluoranthene, benzo[e]pyrene, benzo[a]pyrene, 3-methylcholanthrene, benzo[ghi]perylene, dibenz[a,h]anthracene, and dibenz[a,l]anthracene. Nanofiltration proved to be the most effective method, achieving up to 71% removal efficiency for domestic wastewater, and demonstrated high effectiveness for other sources as well. Coagulation-flocculation, ultrafiltration and adsorption showed moderate effectiveness with performance values of 33% - 49%, 33% - 50% and 33% - 44% respectively. Specifically, nanofiltration achieved removal rates of up to 71%, 57% - 71%, 57% - 100%, and up to 86% for domestic, industrial, agricultural, and pharmaceutical wastewater, respectively.