A COST ANAYLYSIS OF THE MEMBRANE BIOREACTOR (MBR) PROCESS FOR WATER RECLAMATION

As a part of the Bureau of Reclamation funded project, “Membrane Bioreactors (MBRs) for Water Reclamation-Phase II”, a cost analysis was performed to determine the feasibility of fullscale applications of the MBR process compared to current wastewater technologies. Cost analyses were performed for 1 and 5-MGD (3,785 and 18,927 m3/d) installations producing: (1) secondary effluent, (2) Title 22 reclaimed water and (3) feed water to a reverse osmosis (RO) membrane system. Both capital and operations and maintenance (O&M) costs were evaluated to produce a present worth value for each treatment option considered. This preliminary cost evaluation showed that conventional treatment in the form of an oxidation ditch was most economical for the production of secondary effluent (2.66/kgal and 1.57/kgal for 1 and 5- MGD installations, respectively). The most cost effective treatment process producing Title 22 reclaimed water was an oxidation ditch with granular filtration and chlorination (2.89/kgal and 1.70/kgal, respectively). The most cost effective treatment process producing feed water for an RO membrane system was an MBR system (3.05/kgal and 1.92/kgal, respectively).