The CleanSwitch regenerative thermal oxidizer with secondary heat-recovery from MEGTEC Systems Inc. is a 25,000 scfm capacity unit with thermal efficiencies of up to 95%, coupled with a relative payback period of approximately two years.
First American Resources Co., Mableton, GA, manufactures high-quality, pre-coated aluminum and steel coils for the building and automotive industries. Its coatings are all solvent-based and include various adhesives, polyesters and polyvinyl chloride (PVC) paints. Its products are used to make automobile window and door seals, engine head gaskets, residential windows and housing exterior trim.
Two years ago, the company was faced with needing to upgrade its pollution control equipment. “Our two main objectives were to ensure ongoing environmental compliance and reduce energy consumption,” explained Stan Hollander, president and chief executive officer. “Our emission control equipment at the time was 15 years old. It still met EPA permit requirements, but it was very inefficient. We determined the best course of action was to upgrade to new technology.”
An Efficient RTO
First American chose the MEGTEC CleanSwitch™ regenerative thermal oxidizer (RTO), with secondary heat recovery. The 25,000-standard cubic feet per minute (scfm) capacity unit has thermal efficiencies of up to 95% and a 99%+ volatile organic compound (VOC) removal rate. In addition, the unit can run in a self-sustaining mode, meaning that no additional fuel is required to destroy VOCs. The unit has a relative payback period of approximately two years.MEGTEC custom designed the system to fit the available space at the First American facility. The technology incorporates an efficient heat recovery system to reduce energy usage of the control device to a fraction of the amount used by First American’s previous environmental control technology.
An air-to-air heat recovery system further reduces process energy usage. The RTO system uses the hot, clean exhaust from the oxidizer to preheat the make-up air used in the process dryers first. The RTO exhaust is sent through one side of a secondary plate-and-frame heat exchanger, while process make-up air is routed through the other side of the exchanger.
Cost Savings and Other Benefits
By reducing emissions more than 80%, First American was able to move to a different level of EPA permitting. This enabled the company to drop its Title V application and go with a Synthetic Minor permit classification, which is at the 25-ton level.“We held a 50-ton permit in the event we decided to expand production,” said Rick Blackmer, director of engineering and quality assurance. “With our reduced emissions load now at about 2 tons annually, we can add another line and still operate well within the compliance guidelines.”
Blackmer estimates that the Synthetic Minor permit fee will save between $5,000 and $10,000 annually in reduced emission fees, paperwork, human resources and less rigorous reporting requirements.
In addition to saving First American money on energy costs and permitting fees, the new technology is also garnering the company accolades from environmental organizations. In February 2007, First American was recognized by the Georgia Chapter of the Air & Waste Management Association with its annual environmental award in the category of air (minor source). The award recognized First American for:
- Reducing natural gas consumption more than 50% for its coating lines, yielding energy cost savings of more than $10,000 per week.
- Reducing VOC emissions more than 80%, from 17 to 18 tons annually, to approximately 3 tons per year.
- Increasing VOC and HAP destruction rates from 97.8 to 99.4%.
- Improving coating room ventilation and dryer efficiency by installing exhaust fans and hoods to pull solvent vapors away from operators. The solvent-laden air is then preheated in a heat recovery system before being sent back to the process dryers.
For more information about the RTO technology, contact Mary Van Vonderen at MEGTEC at 920.339.2787 or mvanvonderen@megtec.com. The company’s website is at www.megtec.com.
More information about First American Resources Co. can be found at www.firstamericancoil.com.
