Development of Biotrickling Filters to Treat Sulfur and VOC Emissions

摘要

The objective of this Phase II Small Business Innovation Research project was to develop an efficient and cost-effective biological process to treat air emissions of significance to the Navy. During Phase I, the feasibility of treating these emissions using a biotrickling filter was tested. Biotrickling filters are similar to chemical scrubbers, but rely on microorganisms on the packing surface to remove and oxidize contaminants rather than chemicals. A 7- month field-pilot demonstration was conducted at North Island Naval Air Station near San Diego, California to demonstrate the effectiveness of the process for treatment of hazardous air pollutants (HAPs) from spray paint booths. Target HAP removals exceeded 88 percent for vapor contact times (packing volume divided by air flowrate) greater than 16 seconds. Carbon dioxide measurements indicated that the dominant removal mechanisms were absorption and biodegradation in the morning hours and biodegradation only in the afternoon hours. Performance was not affected by the intermittent operation in the paint booth. A cost analysis showed that for treatment of the entire air stream, over a 10-year project life, biotrickling filters designed for a 16 or 11 second contact time were less expensive than carbon adsorption or thermal systems.