The design of a combined facility for wastewater and solid waste processing may provide an energy self-sufficient system in an era of rising energy costs and limited fossil fuel reserves. The Central Contra Costa Sanitary District’s facility is designed to combine an existing 1.31m3/s (30,000,000 gal/day) wastewater reclamation plant to provide high-purity water for industrial use and a 1089 Mg/day (1200 ton/day) dry classification type resource recovery plant to provide a refuse-derived-fuel (RDF) from the combustion fraction of solid waste and also to recover metals. This RDF is used as fuel in multiple hearth sewage sludge furnaces. Recovery of the heat from the furnace off-gases provides steam for use in steam turbine driven equipment such as electrical generators and mechanical drives and to meet plant heating and cooling demands. Laboratory and full scale furnace tests demonstrated process feasibility while providing useable design criteria.
Combined Processing of Wastewater and Solid Waste
Authors: Ronald B. Sieger, Brian D. Bracken
1976 AIChE Solids Symposium