Applicability of statistical tools for evaluation of water treatment plants

Abstract

This paper aims to demonstrate the use of some statistical tools to evaluate the performance of water treatment plants (WTP) in terms of water quality effluent. On such a purpose, mean values of daily recorded data on raw water and treated water quality were accounted within the period between 2001 and 2011 at six WTP of which average inflow rate varied from 0.033 to 4.4 m³ s⁻¹. In order to evaluate the seasonality effect on the raw water quality and the performance of such plants, the results found during the wet and dry season were set apart. The results pointed out the feasibility of these statistical tools, and considering the effluent turbidity as the main parameter, the statistical analysis showed that performance level of the plants is not dependent on their sizes or raw water quality. Additionally, all plants evaluated had their performance reduced during the wet season compared to the dry season.

Keywords:

• Performance evaluation
• Statistical analysis
• Reliability analysis
• Water treatment

Notes

¹ Depending on the accumulated probability (reliability), this parameter takes the values 2.326 (99%), 1.645 (95%), 1.282 (90%), 0.842 (80%), 0.525 (70%), 0.253 (60%), and zero (50%).