Full-scale experience with the membrane bioreactor-reverse osmosis water reclamation process

Abstract

The Gippsland Water Factory (GWF), owned and operated by Gippsland Water in south eastern Australia, is a 35,000 m3/day water reclamation facility which treats 16,000 m3/day of domestic wastewater and 19,000 m3/day of industrial (pulp and paper) wastewater through parallel membrane-bioreactor (MBR)-based treatment trains prior to discharge to the Pacific Ocean via the Regional Outfall Sewer. A portion of the domestic train MBR effluent is further treated through a chloramination and reverse osmosis (RO) system for reclamation, as needed to augment the regional water supply, and is supplied to Australia Paper, the source of the industrial wastewater treated at the GWF. While use of the MBR/RO combination for water reclamation is expected to provide advantages, little full-scale experience exists. Consequently, this paper reports operational and performance results for the first four years of operation for the MBR/RO water reclamation train. Details are provided, not only on process performance, but also on the resolution of equipment and plant performance issues along with ongoing plant optimization. On the basis of these operating results, it is concluded that the combination of MBR and RO is a reliable and robust option for producing high-quality reclaimed water from municipal wastewater.