Retorting process utilizing a flexible, helical shaped conveyor

Claim 2

A continuous process for retorting hydrocarbon-containing solids which comprises: a. introducing a solid heat-transfer material at an elevated temperature and hydrocarbon-containing solids into a first section of a stationary, elongated vessel; b. conveying said heat-transfer material and said hydrocarbon-containing solids through said vessel by means of a flexible generally helical shaped, elongated, hollow longitudinal core, rotating conveyor disposed in said vessel throughout a substantial portion thereof, whereby said hydrocarbon-containing solids and said heat-transfer material are intermixed and sufficient heat is transferred from said solid heat-transfer material to said hydrocarbon-containing solid to raise the temperature of said hydrocarbon-containing solids to an elevated retorting temperature in said first section of said vessel; c. introducing a stripping gas at an elevated temperature into a third end section of said vessel downstream from the location where said hydrocarbon-containing solids are introduced, and passing said stripping gas through said third section of said vessel in countercurrent flow relative to the flow of said hydrocarbon-containing solids; d. withdrawing at an elevated temperature an effluent stream from a second middle section of said vessel, said effluent stream comprising said stripping gas, entrained liquid and gaseous hydrocarbons and finely-divided solids; e. withdrawing at an elevated temperature retorted solids and said heat-transfer material from said third section of said vessel; f. separating the condensable hydrocarbons from said effluent stream.

Claim 3

The process of claim 1 wherein said hydrocarbon-containing solids are heated to a temperature in the range 800° to 1100° F in said first section of said vessel and said solids are maintained in said second and third sections of said vessel at a temperature within 50° F of the highest temperature attained by said solids in said first section.

Claim 4

The process of claim 2 wherein said hydrocarbon-containing solids are heated to a temperature in the range 850° to 1000° F in said first section of said vessel and said solids are maintained in said second and third sections of said vessel at a temperature within 25° F of the highest temperature attained by said solids in said first section.

Claim 5

The process of claim 1 wherein said vessel is substantially horizontal.

Claim 6

The process of claim 1 wherein said hydrocarbon-containing solids comprise shale.

Claim 7

The process of claim 5 wherein said stripping gas comprises the normally gaseous components of shale oil.

Claim 8

The process of claim 1 wherein said hydrocarbon-containing solids are introduced into said vessel at a temperature from 50° to 700° F and said solid heat-transfer material is introduced into said vessel at a temperature from 1200° to 1700° F.

Claim 9

The process of claim 1 comprising the additional step of separating a normally gaseous stream from said effluent stream and recycling at an elevated temperature at least a portion of said normally gaseous stream to said vessel as said stripping gas.

Claim 10

The process of claim 1 wherein said vessel is maintained essentially free of molecular oxygen.

Claim 11

A continuous process for retorting shale which comprises: a. introducing spent shale at an elevated temperature in the range 1200° to 1700° F and hydrocarbon-containing shale at a temperature in the range 50° to 750° F into a first section of a stationary, substantially horizontal, elongated, cylindrically-shaped vessel; b. conveying said spent shale and hydrocarbon-containing shale through said vessel by means of a flexible, generally helical shaped, elongated, hollow longitudinal core rotating element whereby said spent shale and said hydrocarbon-containing shale are intermixed and sufficient heat is transferred from said spent shale to said hydrocarbon-containing shale to raise the temperature of said hydrocarbon-containing shale to a temperature in the range 875° to 975° F in said first section of said vessel; c. introducing a stripping gas at an elevated temperature in the range 875° to 975° F into a third section of said vessel downstream from the location where said hydrocarbon-containing solids are introduced, and passing said stripping gas through said third section of said vessel in countercurrent flow relative to the flow of said spent shale and said hydrocarbon-containing shale whereby said hydrocarbon-containing shale is maintained at a temperature of at least 875° F in said third section; d. withdrawing at an elevated temperature in the range 875° to 975° F an effluent stream from a second middle section of said vessel, said effluent stream comprising said stripping gas, entrained liquid and gaseous hydrocarbons and finely-divided solids; e. separating the condensable hydrocarbons from said effluent stream; f. withdrawing at an elevated temperature in the range 875° to 975° F retorted shale containing essentially no volatilizable hydrocarbons and said spent shale from said third section of said vessel; g. passing said retorted shale and said spent shale into a combustion zone and combusting the residual carbon on said retorted shale forming spent shale at a temperature in the range 1200° to 1700° F; h. introducing at least a portion of said spent shale from step (g) into said first section of said vessel.

Claim 12

A continuous process for retorting shale which comprises: a. introducing spent shale at an elevated temperature in the range 1200° to 1700° F and hydrocarbon-containing shale at a temperature in the range 50° to 750° F into a first section of a stationary, substantially horizontal, elongated, cylindrically-shaped vessel; b. conveying said spent shale and hydrocarbon-containing shale through said vessel by means of a flexible, generally helical shaped, elongated, hollow longitudinal core rotating element whereby said spent shale and said hydrocarbon-containing shale are intermixed and sufficient heat is transferred from said spent shale to said hydrocarbon-containing shale to raise the temperature of said hydrocarbon-containing shale to a temperature in the range 875° to 975° F in said first section of said vessel; c. introducing a stripping gas at an elevated temperature in the range 875° to 975° F into a third section of said vessel downstream from the location where said hydrocarbon-containing solids are introduced, and passing said stripping gas through said third section of said vessel in countercurrent flow relative to the flow of said spent shale and said hydrocarbon-containing shale whereby said hydrocarbon-containing shale is maintained at a temperature of at least 875° F in said third section; d. withdrawing at an elevated temperature in the range 875° to 975° F an effluent stream from a second middle section of said vessel, said effluent stream comprising said stripping gas, entrained liquid and gaseous hydrocarbons and finely-divided solids; e. separating the condensable hydrocarbons from said effluent stream; f. withdrawing at an elevated temperature in the range 875° to 975° F retorted shale containing essentially no volatilizable hydrocarbons and said spent shale from said third section of said vessel; g. passing said retorted shale and said spent shale into a combustion zone and combusting the residual carbon on said retorted shale forming spent shale at a temperature in the range 1200° to 1700° F; h. introducing at least a portion of said spent shale from step (g) into said first section of said vessel.