Orange County Sanitation District, CA

IMANSTM  Pilot Plant and Microfiltration Demonstration Projects

ORANGE COUNTY SANITATION DISTRICT, CALIFORNIA

Highlights
• Bridged  the gap between research and innovative engineering solutions.
• Novel process proposed by Carollo to produce reusable water from primary treated wastewater with quality in excess of California Title 2 2 standards.

The Orange County Water District and the Orange County Sanitation District have formed a Groundwater Replenishment System Joint Committee. In 1998, the committee approved a project to evaluate an integrated treatment process using membrane and anaerobic processes to treat wastewater and produce a high- quality effluent for recharge into the Orange County Groundwater Basin.

The investigations evaluated the performance of a simple novel process scheme proposed by Carollo to produce high-quality reusable water (in excess of California Title 22 standards) from primary treated wastewater. Basically, the process train involves a two - step membrane process integrated with a high-rate anaerobic digestion step, called the IMANS™ process. Primary effluent is treated by microfiltration in a non-biological step, followed by RO to produce a high-quality water for reuse or groundwater injection. The 18-month pilot test proved the technical feasibility of the treatment approach.

The Orange County Sanitation District proceeded with further testing of the process on a larger scale. A 0.3-mgd MF plant has been in operation since January 2002 as part of the MF demonstration project.




IMANS™ is an innovative two -step membrane process integrated with a highrate anaerobic digestion step. The control panel (top) and submerged MF membrane unit (right) are shown here.