Expert: Dave Russell - 10/28/2010

Question
What are the most common methods/devices used in large-scale
automotive paint operations to control VOC emissions and
approximate cost of such devices?

Answer
The one I'm most familiar with was used by General Motors at their plants in New York, and Georgia. The key is large scale. That means highly automated equipment, low VOC paints (see the EPA for the VOC requirements on paints), an electrostatic spray system, an automatic system (robots) for application, and a specially designed spray booth. Over the last 20 years, the design has become totally automated where little or no human interaction is required for the paint booth. The frames and parts are moved via conveyor belt into a paint booth tunnel. The pain is sprayed on (after the car is prepped by phosphatizing)and moved directly into a drying tunnel.
The air in the tunnel is virtually clean room quality -- highly filtered, and very clean and dust free.
The principal control was formulation of the paints to remove the VOC's and then it was an catalytic destructor on any exhaust air.
The cost for an automated system like that is measured in the millions of dollars, and I don't know what the full cost was, but when GM went to expand the Doraville Plant, now closed, back in the late 1980's or early 1990's, they built an entire building to handle the phosphatizing, painting and various treatment equipment for wastewaters. Reportedly at that time they spent over $100,000,000 for the new paint booth building (300,000+ square feet in about 4 stories, maybe more).
The booth is custom built, and with the controls, it was very expensive but I can't speak to the costs more than the gross figure. The wastewater treatment system was also custom, and so was the air pollution (VOC) control system, but essentially it was a large catalytic combustor (which is very expensive to operate).

Hope that helps.