CHEMICAL AND MICROBIALLY-ASSISTED LEACHING OF ATHABASCA OIL SANDS COKE

Abstract

The vast deposits of oil sands in the Province of Alberta Canada bear significant quantities of vanadium, nickel, titanium and iron in the bitumen component. During the production of oil from this bitumen, the metals are concentrated in the coke and coke ash refinery by-products. This study is concerned with the removal of metals, particularly vanadium, from the coke and coke ash obtained from different coking processes. The feasibility of marketable metal recovery by both chemical and microbially assisted leaching techniques has been assessed. Further the environmental impact of the solid waste disposal of untreated coke and coke ash has been evaluated by investigating the mechanism and extent of metal leaching under natural conditions and by investigating the toxicity of these "natural" leachates in a novel bioassay system. The study presents the data obtained in a critical evaluation of the leaching of metals from coke and coke ash in both economic and ecological contexts.