Demonstration Testing of ZenoGem and Reverse Osmosis for Indirect Potable Reuse

Report #51 - Abstract -

This study involved demonstation-scale testing of an integrated membrane bioreactor (MBR)/reverse osmosis (RO) treatment train to reclaim the City of McAllen's municipal wastewater to a quality suitable for use as a new drinking water supply. The demonstration testing objectives included: (1) demonstrate that RO product water meets all federal primary and state secondary drinking water regulations; (2) demonstrate reliable operation of the MBR on screened, de-gritted sewage, particularly with respect to control of membrane fouling through automatic cleaning; (3) demonstrate the MBR filtrate (RO feedwater) can be efficiently processed by composite RO membranes with minimal fouling; and (4) develop estimates of capital and operating costs for a MBR/RO system.

The results showed that: (1) the ZenoGem process is capable of producing a filtrate suitable for RO treatment while meeting the City's current wastewater effluent discharge requirements; and (2) the RO system is capable of producing a filtrate that meets all drinking water/reuse standards with minimal fouling and effective membrane cleanings.