A regenerative thermal oxidizer from Pro-Environmental Inc. treats distillers dried grains with solubles at this Minnesota ethanol plant.

The emissions from a rotary dryer processing distillers dried grains (DDG) with solubles at an ethanol plant needed treatment to comply with Environmental Protection Agency regulations, so the plant's operator turned to Pro-Environmental Inc., Rancho Cucamonga, Calif., for a regenerative thermal oxidizer (RTO) to do the job.

According to Pro-Environmental, the application presented three special challenges during the oxidizer design due to the nature of the exhaust. The exhaust:
  • Varied constantly and had very low oxygen content.
  • Had high moisture content with corrosive compounds.
  • Had high required destruction efficiency.
The solution that best dealt with the difficulties was a three-canister thermal oxidizer with a purged design made from corrosion-resistant materials. The burner systems and combustion air blower were designed to address the constantly varying combustion air requirements.

The unit was installed and started up on schedule. Performance testing was conducted a few weeks after the equipment was fully operational, and the system met or exceeded EPA standards, according to Pro-Environmental.

Contact Pro-Environmental at (909) 989-3010 or www.pro-env.com.