Analysis of the factors influencing the removal of oil from used automotive oil filters during recycling operations

Abstract

Abstract More than 425 million used oil filters (UOFs) are discarded annually in the United States. These filters contain an estimated 67 500 m 3 (17.8 million gallons) of used oil that could leach from landfills and pollute soil and water. The Environmental Protection Agency (EPA) has mandated that non terne-plated used oil filters which have been gravity hot drained for at least 12 h are considered non-hazardous and acceptable for landfilling. Filters must be either punctured in the dome end, punctured in the anti-siphon valve, or crushed before draining to meet the requirements for this EPA exemption. This paper evaluates the factors which affect the removal of used oil from UOFs by gravity hot-draining and crushing. The factors studied include oil temperature and viscosity, dome-end puncturing, draining orientation, filter design, time, and crushing force. Of these factors, oil temperature, puncturing of the dome end, filter orientation, and filter design were found to have a significant impact on oil removal by gravity draining. Orientation is very important because an oil filter drained to EPA's recommendations still contains a significant quantity of oil which has a high probability of draining because of normal changes in the orientation of a filter during transport or placement in a landfill. During crushing, oil temperature, filter design, and crushing force were found to significantly impact oil removal.