Statistical Monitoring of a Biological Wastewater Treatment Process

Abstract

Background: Wastewater/Sewage influent & effluent quality and effluent reutilisation can be assessed with the help of various statistical and multivariate tools. Nowadays, these tools have proved to be efficient method for the quality assessment and management of various wastewater treatment technologies. Objective: The present study is carried out on the influent and effluent of Dr. Sen Nursing Home Sewage Treatment Plant (STP), New Delhi, India based upon BIOFOR which is a biological treatment technology. The basic objective of the study is to carry out statistical monitoring of all the physiochemical parameters and to identify treatment process performance, the interdependencies between the variables. Methods: The raw sewage (influent) and treated sewage (effluent) data of the STP was subjected to paired t-test, Principal Component Analysis (PCA) and Biodegradability Index (B.I). All the Statistical Analysis was performed using SPSS 22.0 and MS-Excel. Findings: The paired sample t-test proved that all the physicochemical parameters vary significantly in the influent and effluent (p < 0.05) indicating that the technology is effectively functioning for the treatment of raw sewage.  PCA reduced the dimensionality of wastewater data (influent and effluent) into three factors which accounted for 68.05% and 72.053% respectively of the total variance in the dataset. The study also utilized the Biodegradability Index which was applied to both influent and effluent data and the results obtained revealed that the technology is very much efficient in treating influent with production of effluent of high quality. Application: BIOFOR technology can be considerable coupled with another conventional sewage treatment technologies giving low performance (which are currently used in different STPs of New Delhi) to increase their effectiveness and get the optimum results.