USING A MEMBRANE BIOREACTOR TO RECLAIM WASTE-WATER

A pilot-scale membrane bioreactor sufficiently purified simulated muni cipal wastewater for indirect recharge to groundwater or nonpotable us es. Throughout more than 500 days of steady-state operation, total org anic carbon concentrations of <1.1 mg/L and chemical oxygen demand of <3.5 mg/L were consistently achieved. No suspended solids were detecte d in the effluent during this period. The treated water was fully nitr ified, resulting in low ammonia and organic nitrogen concentrations bu t high nitrate concentrations. Cyclic oxic-anoxic operation or an addi tional denitrification process would be necessary to meet potable wate r reuse standards. Phosphorus was fully used in the viruses were compl etely retained by the membrane system, reducing the extent of final di sinfection required.