초록 ▼

A continuous process for recovery of oil and energy from oil shale. Particulate oil shale (1) is mixed with hot particulate heat carrier (2) containing free lime and retorted at conventional retorting temperatures in the presence of a purge gas (3). The purge gas comprises compounds which can react

A continuous process for recovery of oil and energy from oil shale. Particulate oil shale (1) is mixed with hot particulate heat carrier (2) containing free lime and retorted at conventional retorting temperatures in the presence of a purge gas (3). The purge gas comprises compounds which can react with the free lime. The mixture of spent shale and heat carrier solids (5) is separated from the product gas and vapors (4) and the solids are combusted in air (6),(7) with the optional addition of materials (8) to control the free lime content of the ash product from combustion. A stream of particles (12), extracted from the combustor is separated into a larger portion of coarser hot shale ash which is recirculated to the retorting zone as heat carrier. A smaller stream (15) is disposed of as waste after separating the energy (17) therefrom. The sensible and chemical heat from the waste solids and the sensible heat from the gases leaving the combustion zone, is recovered (J).

대표청구항 ▼

A continuous process for the recovery of hydrocarbon values from oil shale with the simultaneous recovery of energy from by-product streams, comprising the steps of: (a) retorting said shale by intimately mixing particulate oil shale with a process derived hot particulate heat carrier ash containing

A continuous process for the recovery of hydrocarbon values from oil shale with the simultaneous recovery of energy from by-product streams, comprising the steps of: (a) retorting said shale by intimately mixing particulate oil shale with a process derived hot particulate heat carrier ash containing free lime in the form of calcium oxide or hydrated calcium oxide to produce additional heat, to clean the product gases, and to convert the reacted gases to solid phases; the temperatures and relative ratios of the shale, the heat carrier ash, and purge gas upon introduction into the retorting zone being selected so that the outlet temperature of the mixture of solids upon retorting is within the range of conventional retorting temperatures; (b) separating the mixture of spent shale and heat carrier solids from the product gases and vapours containing the desired hydrocarbon values; (c) producing the heat carrier ash having a calcium oxide content and a temperature required for use in the retorting zone, said heat carrier ash being produced in a combustion zone by: (i) burning the carbonaceous residues or solids from the retorting zone in admixture with controlled quantities of extraneously added solids and gases containing free lime, (ii) controlling the average residence times of the phases while also maintaining the combustion temperature within a range which allows for sulphur capture, or (iii) employing a combination of (i) and (ii); (d) separating a portion of the coarser hot shale ash from the solids leaving the combustion zone and recirculating this hot stream of solids to the retorting zone as the heat carrier; and (e) recovering the sensible and chemical heat from the waste solids and the sensible heat from the gases leaving the combustion zone; wherein the purge gas for retorting contains steam, and in which a substantial part of the heat required for retorting is supplied by reaction of the steam with the lime contained in the heat carrier solids, while maintaining the retorting temperature at a level below 520°C. and the partial pressure of steam in the range of 0.1-1.0 bar.