17 DEC 2003
1 - Upflow continuous backwash filter: 1.4-m (54-in.) diameter with 1.4-mm
1 - Thickening tank: 37,850 L (10,000-gal.).
1 - Return flow pump: 3.8 L/s at 92.2 kPa (60 gpm at 13.1 psi).
1 - Sludge drying bed.
Figure C-1. Upflow Continuous Backwash Filter Schematic
DOWNFLOW CONTINUOUS BACKWASH FILTER. The water to be filtered
is pumped from a groundwater remediation system. Recovery wells each yield 12 L/s
(190 gpm) of contaminated groundwater. A system was needed that could operate with
intermittent staffing. Air stripping for removal of the volatiles will precede the filter or fil-
Treatment System. The treatments system will be as generally indicated in
Figure C-2. Design a unit operation for the continuous effluent from a single air stripper
at 12 L/m2s (190 gpm) to be in service 24 hours per day 7days per week.