The Environmental Protection Agency's (EPA's) Control Technology Center (CTC) conducted a study to obtain information on the baker's yeast manufacturing industry. Baker's yeast is produced by a fermentation process that generates large quantities of ethanol and acetaldehyde. Currently, 13 facilities produce baker's yeast in the United States. The volatile organic compound (VOC) emission rate from a typical facility is estimated at 82 megagrams per year (90 tons per year). The majority of these emissions occurs in the final trade fermentations. The VOC emission alternatives that were evaluated during the study were process control measures to reduce the formation of VOC emissions as well as wet scrubbers, carbon adsorbers, incinerators, condensers, and biological filters to control VOC emissions. Of these approaches, it appears that process control measures, catalytic incinerators, or a combination of add-on control techniques (e.g., wet scrubbers followed by an incinerator or a biological filter) are the most feasible approaches for controlling yeast process emissions. Based on the results of the study, the control efficiency associated with the add-on control systems is estimated to be 95 to 98 percent. The report contains information on the baker's yeast fermentation process, the number and locations of yeast plants, the potential emissions from the process, and an evaluation of potential emission control options.

"January 1992." "Office of Air Quality Planning and Standards"--Cover. Prepared for Control Technology Center Contract Number: 68-D1-0115 "EPA/450-3-91-027." Includes bibliographical references (pages 44-45).