BIODISPOSAL FARMING OF REFINERY OILY WASTES

Abstract

ABSTRACT Oily waste materials, whether they are derived from oil spill cleanup operations or generated during petroleum processing, present somewhat similar disposal problems which are of major concern. With oily waste disposal in sanitary landfills increasingly unacceptable and with the many problems and high costs associated with incineration, landspreading (landfarming) is becoming more and more important as a disposal method. Although simple in principle, it is somewhat complex in application with little experimental data available. The API has undertaken a study to define the requirements and limitations for an environmentally acceptable landspreading method. Suntech selected three sites in the United States for the study, one of which is discussed in this paper, namely, Toledo, Ohio. Typical refinery oily wastes were spread on test plots in multiple, controlled applications and tilled into the top eight inches of soil, and the fate of these wastes and their components in the soil environment was monitored for a two year period. Bio-oxidation rates were determined for the oil fractions. Microflora population counts served to monitor the microbial response and determine overall soil viability. Leachate and groundwater quality and surface runoff contamination were studied to assess any tendency toward waste constituent migration. Heavy metals, phenolics, and cyanides were also examined. Biodegradation rates were found to be substantial, with controlled applications in excess of 1,000 barrels of oil per acre per year.