Abstract: Water is added to reduce the hydrogen consumption in kerogen conversion. The water is not stripped from oil shale ores, instead up to 10% w/w of water is added in the kerogen conversion at 400-475° C. The recycle solvent for conversion is changed to a high boiling point fraction of the oil, with a minimum boiling point of the order of 245° C. Such repeated recycling of high boiling fraction oil with a hydrogen-donor mid-distillate will remove additional sulphur, oxygen and nitrogen. It improves the quality of the final product oil. Most of the high boiling fraction of the oil will separate from the oil shale ores, at around 450° C. and 650 psig. Then it is reduced to 250° C. at 100 psig before distillation. Such column operates at around 10 to 250 psig, but preferably 50 psig. This improves thermal efficiency by avoiding the need to condense high boiling point vapors. The addition of water provides further enhancement in operating results.

Abstract: A method and apparatus for the extraction of hydrocarbon products, alumina and soda ash from oil shales including various amounts of such chemicals, all based on solvent extraction of most of the hydrocarbons at temperatures around 400° C. Such enables the alumina and soda ash values to be leached out with aqueous sodium carbonate leaching at reduced temperatures of around 150° C. with a corresponding reduced pressure. The soda ash monohydrate values are precipitated from the leach liquor at around 100° C. with the alumina values precipitated using CO2. Alternatively recycled fine aluminum trihydrate at 65° C. is used to produce alumina. Aluminum hydroxide is converted to acid alumina by an acid recycle stream that dissolves the alumina so any silica contaminant can be filtered out. Basic aluminum sulfate is then precipitated at about 200° C. and 250 PSIG for subsequent calcination at around 900° C. This produces alumina and sulphate oxide gasses are recycled via a sulphuric-acid plant.