A NEWFIELDS INNOVATIVE APPROACH: YEAST-BASED TREATMENT SYSTEMS
The process engineering group specializes in the treatment of industrial wastewater. Industrial wastewater is highly variable in chemical composition and is often not suitable for discharge to local receiving waters or the sanitary sewer without significant pretreatment. Recently, our engineers have been researching the treatment of dairy processing wastewaters which contain whey, a by-product of cheese manufacturing.  This wastewater typically has a COD of 40,000 – 60,000 mg/L which presents unique demands on treatment facility design compared to a typical municipal wastewater COD of 500 mg/L.  Over the past several years, Dr. Matthew Frigon has researched utilizing yeast instead of bacteria for the treatment of high strength (high COD/BOD) and high salinity wastewater. An advantage of yeast is that soluble organic products can be transformed into yeast biomass (single cell protein/SCP) that has excellent nutritional characteristics, especially with regard to amino acid content. This biomass can then be mixed with an energy source (a carbohydrate such as corn or starches) and fed to livestock as opposed to landfill disposal. Using a particular strain of yeast that can consume lactose, Dr. Frigon was able to operate a bench scale system that reduced the COD of a formulated acid whey wastewater by >90% and produced a biomass that met or exceeded FAO guidelines for animal feed in all but one essential amino acid. Due to the ability of yeast to withstand high osmotic pressures and high organic loading, the reactor was ~80x smaller than a typical aerated bacterial system and 2x smaller than a typical anaerobic system. Further, oxygen consumption in the system was significantly reduced in comparison to aerobic bacterial system thereby substantially reducing operational costs.

Based on this innovative research, yeast-based treatment systems are ideal for treatment of wastewater from cheese, yogurt, sport supplement, and associated dairy wastes.