Published in 1975
A pilot laboratory treatment system was successfully employed to investigate the reuse of wastewater for flushing toilets at highway rest areas. This extended aeration unit used a synthetic waste to determine if the biological system could operate efficiently at high dissolved solids concentrations produced by effluent recycle rates of up to 95 percent. Effluent quality and sludge accumulation rates were monitored, and biological solids control methods were studied. Results from pilot plant performance with and without recycle show that treatment efficiency, in terms of a biologically degradable effluent, will not be adversely affected by high recycle ratios. The use of dye to distinguish recycle water from potable water was explored. Included in this research was the selection, quantification, and removal of this artificial color from recycled effluent. Sodium fluorescein was found to be susceptible to biological attack and sunlight, and to be readily removable by carbon adsorption. The small volumes of effluent water produced by a recycle system have the potential to be impounded and either partly or completely disposed of by solar evaporation, depending on the rest area location, climatological data were used to predict net evaporation rates for a recycle facility installed at Fairfield, Virginia.
Last updated: February 5, 2024