Ethanol Industry Case Study

Application of Regenerative Thermal Oxidation for VOC control on Fermentation Scrubbers

Resulting from the large demand for alternative fuels, Ethanol plant construction has spread to most areas of the country. Until recently, the focus of environmental regulators has been to control air emissions from boilers, DDG and DDGS dryers. Each state has regulated emission limits which, in some cases, are more stringent than federal guidelines. California is an example of a state where the focus was placed on controlling alternative emission sources to allow the facility to be permitted as a “significant minor” or “minor” source.

In August of 2006 NESTEC, Inc. supplied a regenerative thermal oxidizer to control the fermentation scrubber and load out station emissions at Pacific Ethanol’s Madera, CA facility. This application is unique because the fermentation off gas is virtually oxygen free and provides a unique medium to convey the load out gas to the RTO system.

Given their experience with low oxygen applications, NESTEC, Inc. designed the RTO system to operate at the reduced environment and adjust the oxygen content as needed to achieve oxidation. NESTEC, Inc. was also involved with the design and control of the injection nozzle to uniformly mix the load out gases with the fermentation scrubber off gasses. Appropriate control interlocks were also designed to allow for safe start-up and shut-down procedures.

Should you wish to receive more information on this application please contact NESTEC, Inc. at 215-234-8188.