Emissions Reduction From Digester Gas-Fired Engines At WWTPs

Annual emissions calculated using source testing data and operational information determined that the internal combustion engines (IC Engines) at the Orange County Sanitation District (OCSD) two wastewater treatment plants (WWTPs) are the largest sources of criteria pollutants and air toxics (mostly formaldehyde) emissions from the facilities (Kogan Ahn, Torres, 1994). Both plant are located in the highly populated residential and resort areas with nearby homes and businesses within only 50m (150 ft) from the plants fencelines and popular beaches and resorts not far away. In addition, the emissions of carbon dioxide (CO2), a greenhouse gas, from the IC Engines were larger than all other onsite direct and indirect sources combined. Therefore, the greatest reduction of criteria pollutants, air toxics, odorous compounds, and greenhouse gases from the OCSD WWTPs can be achieved by the reducing emissions from the IC Engines.This paper includes information related to the determination of methods and means for achieving this goal and the detailed description of the pilot study of the catalytic oxidizer system as one of the most promising technologies for controlling emissions.