Bio·Reaction Industries LLC. (BRI) has completed a two-phase project for the design, testing and installation of a biofiltration unit to degrade volatile organic compounds (VOCs) including benzene, toluene, xylenes, ethyl benzene, hexanes, MEK, MIBK, acetone and certain alcohols to reduce emissions from a paint manufacturing facility in Eugene, Oregon. The initial biofilter installed was a modular design with a maximum airflow capacity of 5,000 cubic feet per minute (cfm) and 10-ft x 14-ft x 16-feet dimensions. After 7-months of operation a replacement filter was constructed and installed. The unit is a modular design with a maximum airflow capacity of 10,000 cfm on a 12 x 14ft footprint and a height of 16 feet. The patent-pending BRI bioreactor systems were engineered to provide the optimum environment for sustaining and propagating a healthy microbial community. In the degradation process, VOC-laden air is heated and passed through a water curtain and a wet contact scrubber (initial humidification). Water is continuously recirculated and heated in the base (sump) using plate heaters. Temperature and humidity within the reactor environment are controlled automatically.
Complex communities of microorganisms (bacteria and fungi) propagate on the patent-pending BRI-structured compost-based filter medium. The biological media moisture content is maintained using overhead spray watering systems that can be programmed for regular watering intervals. If additional heat energy is required, live steam can be injected into the inlet air plenum. The VOCs are removed from the air stream through absorption and adsorption followed by biodegradation. The microbe communities metabolize and oxidize the VOCs into CO2, H2O
and biomass. This paper will compare the performance data collected over several months of industrial operation and will provide examples of monitoring and testing scenarios between the two BRI biofilters designs. Additionally, the on-site construction requirements, performance tests, monitoring data and technology comparisons will be presented.