Performance evaluation of ETP from pesticide manufacturing industry by using WWQI and multivariate statistical analysis.

The appropriate operation of wastewater treatment plants is essential to maintain the quality of treated water. The aim of the present study is to monitor the effluent quality by applying the Wastewater Quality Index (WWQI) and statistical method. The influent and effluent wastewater samples were collected from an Effluent Treatment Plant (ETP) of pesticide manufacturing industry in Tamil Nadu, India. The study was carried out during the period 2014-2018. The physicochemical parameters were analyzed to determine the biodegradable and non-biodegradable contaminants in the wastewater. The organic removal in ETP for high Total Dissolved Solids (TDS) wastewater treatment was 97-100% and low TDS wastewater treatment was 96-99%. The overall quality of the wastewater was determined by WWQI using irrigation standards. The quality of all the influent samples was poor. The WWQI of high TDS effluent samples varied from marginal to good. The low TDS effluent quality varied from fair to excellent. The interdependencies between the variables were observed using Principal Component Analysis (PCA). From the influent and effluent variables, five and two PCA components were extracted with 92 and 85% of the total dataset information, respectively. The correlation analysis was carried out to observe the interrelationship between the wastewater quality parameters. The regression model achieved 99% of accuracy for fitting the model with the calculated WWQI. The final effluent showed a higher removal efficiency and better quality to reuse for irrigation. It was concluded that the ETP of the PMI is maintained properly and can be also applied to other industrial wastewater. Graphical abstract.