Retorting oil shale with special pellets and steam stripping

Claim 1

IN A METHOD FOR RETORTING CRUSHED OIL SHALE CONTAINING CARBONACEOUS ORGANIC MATTER AND MINERAL MATTER WHEREIN OIL SHALE IS RETORTED BY CONTACING SAID OIL SHALE WITH HOT PELLETS IN A RETORT ZONE TO GAS AND OIL PRODUCTS, PARTICULATE SPENT SHALE, AND AN ORGANIC COMBUSTIBLE DEPOSITION ON SAID PELLETS AND SAID SPENT SHALE, SAID PELLETS HAVING BEEN HEATED IN A PELLET DEPOSITION BURNING ZONE TO A RETORT ZONE INLET TEMPERATURE OF BETWEEN 1,000*F. AND 1,400*F. MAINLY BY COMBUSTION OF A COMBUSTIBLE CARBON-CONTAINING DEPOSITION ON SAID PELLETS, SAID PELLETS BEING IN AN AMOUNT SUFFICIENT TO PROVIDE AT LEAST 50 PERCENT OF THE HEAT REQUIRED TO VAPORIZE A MAJOR PORTION OF THE CARBONACEOUS MATTER FROM SAID OIL SHALE AND TO HEAT SAID CRUSHED OIL SHALE FROM ITS RETORT ZONE INLET TEMPERATURE TO A RETORT ZONE OUTLET TEMPERATURE OF BETWEEN 800*F. AND 1,150*F., AND WHEREIN SAID GAS AND OIL PRODUCTS ARE SEPARATED AND RECOVERED, THE IMPROVEMENT COMPRISING CONTACTING IN A FIRST STREAM STRIPPING ZONE AT LEAST A PORTION OF SAID PELLETS FROM SAID RETORT ZONE WITH STEAM TO REMOVE A PORTION OF SAID COMBUSTIBLE DEPOSITION ON THE CONTACTED PELLETS, THE TEMPERATURE IN SAID FIRST STEAM STRIPPING ZONE BEING BETWEEN 800*F. AND 1,150*F., RECOVERING AT LEAST A PORTION OF THE REMOVED PORTION OF SAID COMBUSTIBLE DEPOSITION, AND PASSING SAID CONTACTED PELLETS TO SAID PELLET DEPOSITION BURNING ZONE.

Claim 14

A method for retorting of crushed oil shale containing carbonaceous organic matter and mineral matter comprising a. feeding crushed oil shale and pellets to a retort zone, said pellets being comprised chiefly of particulate heat carriers being in a size range between 0.5 inch and approximately about 0.055 inch and having a surface area of between 10 and 150 square meters per gram of pellets, said pellets being at a retort zone inlet temperature between 1,000*F. and 1,400*F. and in a quantity such that the ratio of said heat-carrying pellets to said crushed oil shale entering said retort zone on a weight basis is between one and three, said ratio also being such that the sensible heat in said pellets is sufficient to provide at least 50 percent of the heat required to heat said crushed oil shale from its retort zone feed temperature to a retort zone outlet temperature of between 800*F. and 1,150*F.; b. retorting in said retort zone gas and oil products from said crushed oil shale, thereby forming particulate spent shale and a combustible deposition on said pellets and said spent shale; c. causing said pellets and said spent shale to pass from said retort zone to a particle separation zone and separating from said pellets at least 75 percent by weight of the total spent shale and at least 95 percent by weight of the portion of said spent shale that is smaller in size than said pellets, prior to heating said pellets in a pellet deposition burning zone; d. recovering gas and oil products generated by retorting of said crushed oil shale; e. passing at least a portion of said pellets from sAid separation zone to a first steam stripping zone and at the same time passing steam to said first steam stripping zone into contact with said pellets in said first steam stripping zone to remove a portion of said combustible deposition on the contacted pellets in said first steam stripping zone, the temperature in said first steam stripping zone being between 800*F. and 1,150*F.; f. passing said steam and the removed combustible deposition from said first steam stripping zone and eventually recovering at least a portion of said removed combustible deposition; g. passing said contacted pellets from said first steam stripping zone to a pellet deposition burning zone; h. passing any of said pellets from said separation zone not passed to said first steam stripping zone to said pellet deposition burning zone; i. heating all of said pellets passed to said pellet deposition burning zone to an outlet temperature of between 1000*F. and 1400*F. by burning the combustible carbon-containing deposition on said pellets with a combustion supporting gas; and j. thereafter passing said heated pellets from said pellet deposition burning zone to said retort zone.

Claim 15

A method for retorting of crushed oil shale containing carbonaceous organic matter and mineral matter comprising a. feeding crushed oil shale and pellets to a retort zone, said pellets being comprised chiefly of particulate heat carriers being in a size range between 0.5 inch and approximately about 0.055 inch and having a surface area of between 10 and 150 square meters per gram of pellets, said pellets being at a retort zone inlet temperature between 1,000*F. and 1,400*F. and in a quantity such that the ratio of said heat-carrying pellets to said crushed oil shale entering said retort zone on a weight basis is between one and three, said ratio also being such that the sensible heat in said pellets is sufficient to provide at least 50 percent of the heat required to heat said crushed oil shale from its retort zone feed temperature to a retort zone outlet temperature of between 800*F. and 1,150*F.; b. retorting in said retort zone gas and oil products from said crushed oil shale, thereby forming particulate spent shale and a combustible deposition on said pellets and said spent shale; c. causing said pellets and said spent shale to pass from said retort zone to a particle separation zone and separating from said pellets at least 75 percent by weight of the total spent shale and at least 95 percent by weight of the portion of said spent shale that is smaller in size than said pellets, prior to heating said pellets in a pellet deposition burning zone; d. recovering gas and oil products generated by retorting of said crushed oil shale; e. passing at least a portion of said pellets from sAid separation zone to a first steam stripping zone and at the same time passing steam to said first steam stripping zone into contact with said pellets in said first steam stripping zone to remove a portion of said combustible deposition on the contacted pellets in said first steam stripping zone, the temperature in said first steam stripping zone being between 800*F. and 1,150*F.; f. passing said steam and the removed combustible deposition from said first steam stripping zone and eventually recovering at least a portion of said removed combustible deposition; g. passing said contacted pellets from said first steam stripping zone to a pellet deposition burning zone; h. passing any of said pellets from said separation zone not passed to said first steam stripping zone to said pellet deposition burning zone; i. heating all of said pellets passed to said pellet deposition burning zone to an outlet temperature of between 1000*F. and 1400*F. by burning the combustible carbon-containing deposition on said pellets with a combustion supporting gas; and j. thereafter passing said heated pellets from said pellet deposition burning zone to said retort zone.

Claim 34

A method for retorting crushed oil shale containing carbonaceous organic matter and mineral matter comprising a. feeding crushed oil shale and pellets to a retort zone, said pellets being comprised chiefly of particulate heat carriers being in a size range between 0.5 inch and approximately about 0.055 inch and having a surface area of between 10 and 150 square meters per gram of pellets, said pellets being at a retort zone inlet temperature between 1,000*F. and 1,400*F. and in a quantity such that the ratio of said heat-carrying pellets to said crushed oil shale entering said retort zone on a weight basis is between one and three, said ratio also being such that the sensible heat in said pellets is sufficient to provide at least 50 percent of the heat required to heat said crushed oil shale from its retort zone feed temperature to a retort zone outlet temperature of between 800*F. and 1,150*F.; b. retorting in said retort zone gas and oil products from said crushed oil shale, thereby forming particulate spent shale and an organic combustible deposition on said pellets and said spent shale; c. contacting in a first steam stripping zone said pellets and said spent shale from said retort zone with steam to remove a portion of said combustible deposition on said pellets and said spent shale, the temperature in said first steam stripping zone being between 800*F. and 1,150*F.; d. causing said pellets and said spent shale to pass from said first steam stripping zonE to a particle separation zone and separating from said pellets at least 75 percent by weight of the total spent shale and at least 95 percent by weight of the portion of said spent shale that is smaller in size than said pellets, prior to heating said pellets in a pellet deposition burning zone; e. recovering gas and oil products generated by retorting said crushed oil shale and at least a portion of the combustible deposition removed from said pellets and spent shale in said first steam stripping zone; f. passing said pellets from said separation zone to a pellet deposition burning zone; g. heating all of said pellets passed to said pellet deposition burning zone to an outlet temperature of between 1,000*F. and 1400*F. by burning the combustible carbon-containing deposition on said pellets with a combustion supporting gas; and h. thereafter passing said heated pellets from said pellet deposition burning zone to said retort zone.

Claim 35

A method for retorting crushed oil shale containing carbonaceous organic matter and mineral matter comprising a. feeding crushed oil shale and pellets to a retort zone, said pellets being comprised chiefly of particulate heat carriers being in a size range between 0.5 inch and approximately about 0.055 inch and having a surface area of between 10 and 150 square meters per gram of pellets, said pellets being at a retort zone inlet temperature between 1,000*F. and 1,400*F. and in a quantity such that the ratio of said heat-carrying pellets to said crushed oil shale entering said retort zone on a weight basis is between one and three, said ratio also being such that the sensible heat in said pellets is sufficient to provide at least 50 percent of the heat required to heat said crushed oil shale from its retort zone feed temperature to a retort zone outlet temperature of between 800*F. and 1,150*F.; b. retorting in said retort zone gas and oil products from said crushed oil shale, thereby forming particulate spent shale and an organic combustible deposition on said pellets and said spent shale; c. contacting in a first steam stripping zone said pellets and said spent shale from said retort zone with steam to remove a portion of said combustible deposition on said pellets and said spent shale, the temperature in said first steam stripping zone being between 800*F. and 1,150*F.; d. causing said pellets and said spent shale to pass from said first steam stripping zonE to a particle separation zone and separating from said pellets at least 75 percent by weight of the total spent shale and at least 95 percent by weight of the portion of said spent shale that is smaller in size than said pellets, prior to heating said pellets in a pellet deposition burning zone; e. recovering gas and oil products generated by retorting said crushed oil shale and at least a portion of the combustible deposition removed from said pellets and spent shale in said first steam stripping zone; f. passing said pellets from said separation zone to a pellet deposition burning zone; g. heating all of said pellets passed to said pellet deposition burning zone to an outlet temperature of between 1,000*F. and 1400*F. by burning the combustible carbon-containing deposition on said pellets with a combustion supporting gas; and h. thereafter passing said heated pellets from said pellet deposition burning zone to said retort zone.