East Bay MUD

A pilot project was completed by the East Bay Municipal Utility District, Brown and Caldwell and others. The District processes a large volume of high-strength waste, which includes fats, oils, and grease (FOG), and food waste at their Main Wastewater Treatment Plant (MWWTP) as part of their resource recovery program for producing renewable energy. The MWWTP is a net zero energy facility. FOG and waste feedstocks include fair amounts of grit, rocks, and other unwanted debris that are difficult to remove. These unwanted materials cause excessive problems and grit build-up in the digesters. Grit removal from municipal wastewater is well understood, and there are typical systems available for treatment, but there is limited information available on grit and debris removal from FOG waste. A pilot study was completed on the evaluation of sludge screens and a cyclone-classifier. The performance of standard screening and degritting equipment on blended sludge proved successful.