The practice of recycling filter backwash water (FBWW) has become common in many North
American water treatment plants. Although direct discharge to waterways of clarified waste
streams is a widely practiced disposal method, recycling the generated wastewater is an attractive
option for utilities governed by strict plant economics and increasing government discharge
regulations. Backwashing a plant's conventional or direct filtration process units can consume
up to 3-10 % of the treated water produced, and generates an equally significant volume of
wastewater, termed as filter backwash water (FBWW) that must be managed. Filter backwash
water consists of metal-hydroxides, concentrated microorganisms and dissolved organic and
inorganic contaminants. FBWW and clarifier sludge generally comprise the majority of the
waste residual volume generated, and in relative terms can be collectively referred to as
combined filter backwash water (CFBWW). As a result of pathogen outbreaks attributed to
inadequate clarification of backwash water, utilities are considering more advanced treatment
methods for these waste residual streams. The objective of this study
was to evaluate the impact of blending treated water with FBWW that had been treated with a
submersed ultrafiltration (UF) system. In particular, this study examined water distribution
issues concerning microbiological regrowth and the formation of chlorinated disinfection byproducts
(DBPs) originating from disinfection with free chlorine, chlorine dioxide or
chloramines on water that received a 10% blend of UF treated CFBWW. Includes 3 references, tables, figure.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 260 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 5 |
| Published : | 11/02/2003 |
