Enrichment of organic matter of some Egyptian black shales

Abstract

The present paper focuses on obtaining concentrates enriched with organic matter that could be suitable for a retorting process from two different types of black shales; these are oil shale from the Safaga area on the Red Sea Coast, and carbonaceous shale from the Abu-Zenima area, west Central Sinai. X-ray diffraction and optical polarising microscope are used in evaluating black shale minerals. Attrition scrubbing, hydrocyclone separation, jigging and flotation were conducted for enrichment of organic matter in the black shale samples. Mineralogical studies revealed that, oil shale samples contain bituminous calcareous clay stone, quartz, apatite and pyrite, while the carbonaceous shale contains carbonaceous matter, quartz, and clay minerals. Rabah mine oil shale contains 31˙35% and Abu-Zenima carbonaceous shale contains 35˙21% organic matter. The results of the different separation techniques indicate that jigging, hydrocyclone and flotation techniques successively enriched the organic matter in the oil shale. Meanwhile hydrocyclone could enrich the organic matter in the carbonaceous shale. The organic matter could be enriched in the oil shale and obtained a concentrate with 64˙66% assaying and 68˙46% recovery, in addition to a middling of 24˙05% grade and 5˙25% recovery. The carbonaceous shale was processed to obtain a concentrate with 55˙00% grade and 55˙19% recovery and a middling of 27˙27% grade and 34˙69% recovery.