Factors Affecting Sulfur Reactions in High Sulfur Oil Shale Pyrolysis

Oil shale samples from the Ellajjun area south of Jordan were pyrolyzed in different conditions and environments. Sulfur of shale oil was determined using x-ray fluorescence (XRF). Generated products swept from the retort by several sweeping media; they include nitrogen, water vapor, hydrogen, and mixture of nitrogen and water vapor. Other conditions are 2–11 mm particle size, 1 atm operating pressure, and $410–550°C$ temperature range. The sulfur content of shale oil was found to be $12wt%$ for hydrogen pyrolysis, while water vapor at 1 atm decreased this value to $7wt%$⁠. Hydrogenation of oil shale resulted in $12wt%$⁠. the sulfur content of shale oil being at $420°C$⁠, and then reduced to $10.3wt%$ at temperatures higher than $470°C$⁠. When water vapor is added to nitrogen, the sulfur in the oil shale is increased by $4wt%$⁠. Water vapor sweeping gas increased the sulfur of the shale oil from $6.5wt%$ to $8.1wt%$ compared with a nitrogen pyrolyzing medium. Retorted shale analysis showed $44wt%$⁠, and $31wt%$ is left in the retorted shale of the original $4.5wt%$⁠. Sulfur found in the raw oil shale is unretorted for nitrogen and hydrogen sweeping gases. On the other hand, increasing particle size from 2 mm to 11 mm did not have any significant influence on the sulfur content of the produced shale oil.