Coke formation on recycled combusted Rundle oil shale

• Published in: Fuel (Guildford) 1993, Vol.72 (1), p.119-124
• Main Authors: Day, Stuart J., Killingley, John S.
• Format: Article
• Language: English
• Subjects: Applied sciences; coke; coking; Crude oil, natural gas and petroleum products; Crude oil, natural gas, oil shales producing equipements and methods; Energy; Exact sciences and technology; Fuel processing. Carbochemistry and petrochemistry; Fuels; Oil extraction from wells. Pumping. Shale oil extraction. Well workover; oil shale; Prospecting and production of crude oil, natural gas, oil shales and tar sands; Solid fuel processing (coal, coke, brown coal, peat, wood, etc.)
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/0016-2361(93)90386-G

Results are presented on the coking reactivity of combusted Rundle oil shale towards various shale oil fractions and individual oil components. The quantity of coke formed was not greatly affected by the coking temperature in the range of 500–700 °C. However, the temperature at which the shale was combusted did have a significant effect: considerably more coke was deposited on shale combusted at 700 °C than on shale combusted at 900 °C. There was no apparent difference between the amount of coke formed on shale combusted under dry conditions and the amount deposited on shale which had been combusted in the presence of steam. Shale with an organic carbon content of about 3 wt%, corresponding to material which had been about 50 wt% combusted, showed little difference in coking activity to that of fully combusted shale. The amount of char produced by separate shale oil fractions increased with increasing boiling range. The amount of nitrogen incorporated into the coke also increased with boiling range but at a rate disproportionate to the nitrogen content of the original oil fraction. A range of pure compounds, which are typical oil shale components, were examined with respect to their coking reactivities on combusted Rundle shale. Trends of increasing coke formation as a function of chemical structure and boiling point were observed.