Bio-oxidation Control of Air Emissions from a Phenol-Formaldehyde Resin Product Manufacturing Operation

摘要

From June 6th through September 4th, 2007, a BioReaction Industries pilot unit was operated to demonstrate the control of the air emissions from the manufacture of phenol-formaldehyde based products. The unit consisted of a biotrickling filter followed by a biofilter containing compost-packed, plastic ball media. A slipstream from the product dryer exhaust was directed to the biofilter via a temporary, spiral metal duct. Phenol and formaldehyde were the major pollutants in the exhaust, along with a small amount of methanol. Temporary equipment was also installed to increase the loading of these pollutants on the pilot unit, plus add a fourth contaminant, l-methoxy-2-propanol.Exact VOC removal efficiencies could not be determined during any of the 4 stack sampling occasions. No matter what the influent levels of the 4 compounds detected by the Fourier Transform Infrared (FTIR), the outlet levels were always below its minimum detection level.The airflow was varied while inlet concentrations of formaldehyde and phenol ranged from the low single digits to in excess of 100 ppm. Even though the treated flow rate was increased virtually instantaneously, it had no measurable impact on the compounds emitted.During the highest influent loading, FTIR sampling showed the removal efficiencies to be > 99% for formaldehyde, > 90% for methanol, and > 96% for phenol. The highest removal was achieved in the biotrickling filter section of the system with polishing in the biofilter containing a proprietary media. Testing also confirmed that shutting the system down for a four-day period had no impact on removal efficiency when operation was resumed.