IDENTIFICATION OF INFLUENTIAL PARAMETERS AFFECTING WWQI USING STATISTICAL ANALYSIS WITH REFERENCE TO STP, SRIGANGANAGAR, RAJASTHANRINKU CHAWLA AND ATUL ARORA
Treated wastewater generated from wastewater treatment plants can be considered as a source of ânewâ water. This study aims to propose a single quality parameter, WWQI to evaluate overall performance of STP, Sriganganagar and to identify the main parameters affecting WWQI. Several physico-chemical parameters have been employed to evaluate wastewater quality index (WWQI) of secondary treated water. The study was carried for one year period from Feb.2020 to Jan. 2021 and the parameters were measured twice a month following standard methods. Each parameter was compared with its standard permissible limit as prescribed by BIS-2296. The Waste Water Quality Index (WWQI) reflected that secondary treated wastewater was of moderately good to good quality. The Karl Pearson Correlation matrix has approved the influence of pH, COD, BOD, TH, TA,TDS and NO3 - on WWQI with correlation coefficient (r) >0.5. These seven parameters were examined using multiple linear regression analysis. Relevance and utility of applied regression model was analyzed from R, R2 and adjusted R2values and significance of the regression model was indicated by p-value. Regression equations were developed considering significant parameters using MS-Excel software to calculate WWQI once again and to check degree of match. The results revealed that out of seven parameters only three parameters BOD, TH and NO3 â are statistically significant with p-value < 0.05, so are sufficient to predict treated water quality. The analysis provides an easy and rapid way to estimate as well as to monitor the water quality providing one step ahead towards treated water quality management.