ABSTRACT
Gold Bond Ice Cream Inc., headquartered in Green Bay, Wisconsin, operates a country-wide network of plants producing ice cream novelty products ice cream bars, Popsicles and desserts. Among the various ingredients used in production are milk, cream, ice cream, chocolate, fruit juices, sugar and flavorings. The Gold Bond plant in Hagerstown, Maryland, discharges an average of 60,000 gpd to the City of Hagerstown POTW. Plant wastewater is generated during the cleaning of the production equipment and during the clean-up of product spillage. Although anaerobic treatment was an obvious choice of treatment for the high-strength wastewater, selection of candidate anaerobic processes was more difficult. High total suspended solid (TSS) and FOG levels ruled out attached growth processes such as anaerobic filters, fluidized-bed reactors, or even upflow sludge blanket reactors. The anaerobic contact process is suitable for treatment of the high-TSS and high-FOG wastewater from an ice cream novelty plant. The wastewater fats never caused a foam problem in the bench-scale digesters.
