I have enjoyed learning from your column for some time. Now comes a question of my own. We want to replace two 30-ft long, 300-cu-ft, 1,700°F direct gas fired paint drying furnaces with two three-ft long, two-inch bore, 50-kW-induction heating coils. How do we capture the VOCs to recover, or at least reduce, the VOC emissions? Any good ideas? Thank you. V. D.
Owing to the nature of this question, I suggest you contact a Consultant dealing in Air Quality and Regulatory issues. That being said I will not make specific recommendations. Instead, I will offer the following suggestions: First, you must build an enclosure around the open portions of the oven to contain the VOC-laden exhaust air. Next, you must collect the VOC-laden air and duct it to a processing station, using a blower or other air mover. Finally, you must treat the VOC-laden exhaust air to remove the VOCs in a processing station by incineration or carbon adsorption. If incinerated, the heat generated by this process can be used on the finishing line or elsewhere in the plant. If adsorbed, the solvents from the VOC-laden exhaust air can possibly be regenerated and reused.