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Biofiltration performance: part 2, effect of backwashing
Author(s) -
Miltner Richard J.,
Summers R. Scott,
Wang Jack Z.
Publication year - 1995
Publication title -
journal ‐ american water works association
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.466
H-Index - 74
eISSN - 1551-8833
pISSN - 0003-150X
DOI - 10.1002/j.1551-8833.1995.tb06466.x
Subject(s) - backwashing , chemistry , filter (signal processing) , biomass (ecology) , biofilter , effluent , environmental science , pulp and paper industry , environmental chemistry , environmental engineering , agronomy , biology , geology , engineering , geomorphology , inlet , computer science , computer vision
Backwashing a biological dual‐media filter with chlorinated water results in lower accumulations of biomass at the top of the filter and lower steady‐state removal of TOC, DBP precursors, and ozone DBPs. In a biological dual‐media (anthracite–sand) filter, backwashing with nonchlorinated water did not affect the biomass attached to the media at the top of the filter or the control of total organic carbon, disinfection by‐product (DBP) precursors, or ozone DBPs. Backwashing a similar filter with chlorinated water, however, resulted in lower concentrations of biomass attached to the media at the top of the filter and lower steady‐state removal of the same parameters. A loss of some of the attached biomass at the top of the filter occurred immediately after backwashing with chlorinated water, but later in the filter cycle the biomass recovered to its prebackwashing concentration. Concurrent with this loss of biomass was an increase in the concentrations of ozone DBPs in the filter effluent; these also recovered to prebackwashing concentrations later in the filter cycle.