AWWA WQTC71498

The objective of this study was to determine alternative operational means of reducing particle breakthrough and associated potential risks during filter ripening for a plant that cannot filter-to-waste. The challenge with this particular study was to meet the benchmark for the five-star "Excellence in Water Treatment" category established by the International Water Treatment Alliance (IWTA). In this IWTA category, the 95th percentile of filter turbidity values must be 0.10 NTU or less. Accordingly, this project assesses a ripened filter on the basis of a turbidity of 0.10 NTU. This study focused on extended terminal subfluidization wash (ESTW) and filter resting for optimizing filter ripening sequences (FRS). The ESTW procedure involves extending the normal backwash duration at a subfluidization flow rate for an amount of time sufficient to move one theoretical filter-volume of water through the filter box (Amburgey, 2005). Includes 9 references, tables, figure.