Method for the energy-efficient and environmentally friendly obtention of light oil and/or fuels on the basis of crude bitumen from oil shales and/or oil sands

Abstract

The present invention relates to a method for the energy-efficient and environmentally friendly obtention of light oil and/or fuels on the basis of crude bitumen from oil shales and/or oil sands ( 1 ) by thermal use of carbonaceous residues which are obtained during this process, whereby the carbonaceous residues are converted at temperatures below 1800° C. into sulfur-poor, gaseous cleavage products ( 31 ) by sub-stoichiometric oxidation with oxygen-containing gas in an updraft gasifier ( 19 ) which is operated with a bulk material moving bed while alkaline substances are added. The cleavage products are then converted into sensible heat by hyperstoichiometric oxidation and are used for the production of heated aqueous process media ( 2 ) for physically comminuting the oil sands and/or oil shales ( 1 ) and/or for separating of the crude bitumen ( 7 ) from the rock material and/or as process heat for the thermal fractioning ( 12 ) of the crude bitumen ( 7 ).

1 . A method for energy-efficient, environmentally friendly extraction of light oil and/or fuels from crude bitumen from oil shale and/or oil sands by thermal exploitation of carbon-containing compounds occurring in this extraction, characterized in that the carbon-containing compounds contain sulfur and by substoichiometric oxidation with oxygen-containing gas in a countercurrent gasifier operated with a moving bed of bulk material are converted, with the addition of alkaline substances, at temperatures <1800° C. into low-sulfur gaseous cleavage products, and these cleavage products are then converted by superstoichiometric oxidation into perceptible heat, and are used for generating heated aqueous process media for a physical comminution of the oil sands and/or oil shale and/or for separating the crude bitumen out of the rock mass and/or as process heat for a thermal fractionation of the crude bitumen. 
     
     
         2 . The method of  claim 1 , characterized in that as carbon-containing compounds, solid residues from the aqueous separation of crude bitumen from the rock mass and/or solid residues from the thermal fractionation of the crude bitumen are used. 
     
     
         3 . The method of  claim 1 , characterized in that the countercurrent gasifier is embodied as a vertical process chamber with a calcination zone and an oxidation zone, in which the calcined carbon- and sulfur-containing residues oxidize with oxygen-containing gas, and the gaseous reaction products are drawn off at the top of the vertical reaction chamber, the vertical process chamber being in the form of a vertical shaft furnace, through which a bulk material that itself is not oxidized flows continuously from top to bottom, and the oxygen-containing gas is introduced at least partially below the oxidation zone, thereby further advancing the rising gas stream. 
     
     
         4 . The method of  claim 1 , characterized in that as alkaline substances, metal oxides, metal carbonates, metal hydroxides or mixtures of two or three of these substances are used, and are metered purposefully into the vertical process chamber and/or into the gas phase above the calcination zone, and/or are admixed with the carbon-containing compounds before entering the vertical process chamber. 
     
     
         5 . The method of  claim 4 , characterized in that the metal oxides, metal carbonates, and metal hydroxides contain elements of the alkali metals or elements of the alkaline earth metals and especially preferably contain calcium as a cation. 
     
     
         6 . The method of  claim 1 , characterized in that the alkaline substances are used at least partially in fine-granular form with a particle size of less than 2 mm. 
     
     
         7 . The method of  claim 1 , characterized in that the substoichiometric oxidation is performed at a lambda of less than 0.5 and especially preferably of less than 0.3. 
     
     
         8 . The method of  claim 1 , characterized in that by addition of alkaline substances under reductive conditions, the gaseous sulfur compounds occurring in the countercurrent gasifier are converted at temperatures of above 400° C. from the ingredients of the carbon- and sulfur-containing residues by chemical reaction with the alkaline substances into solid sulfur compounds, and these solid sulfur compounds are at least partially carried out with the gaseous reaction products, and are removed from the gas phase by fine-material separation at temperatures above 300° C. 
     
     
         9 . The method of  claim 1 , characterized in that in the vertical process chamber and/or in the gas phase of the drawn-off gaseous reaction products in the presence of water vapor and calcium oxide and/or calcium carbonate and/or calcium hydroxide, a calcium-catalyzed reformation of substantial proportions is performed, at temperatures of above 400° C., of the resultant cleavage products, containing oil and/or tar, that have a chain length of greater than C4, into carbon monoxide, carbon dioxide, and hydrogen. 
     
     
         10 . The method of  claim 1 , characterized in that the moving bed of bulk material is formed partially by additional metering of coarse material, in order to increase the flowability of the bulk material and/or its gas permeability, and the coarse material is admixed with the carbon-containing compounds before entering the vertical process chamber. 
     
     
         11 . The method of  claim 10 , characterized in that as the coarse material, mineral substances and/or other inorganic substances or mixtures of substances, having a particle size in the range of from 2 mm to 300 mm, and especially preferably oil sands and/or oil shale, are used. 
     
     
         12 . The method of  claim 10 , characterized in that as the coarse material, wood and/or other biogenic materials having a particle size in the range of from 2 mm to 300 mm are used. 
     
     
         13 . The method of  claim 10 , characterized in that the coarse material at the lower end of the vertical process chamber is separated from the fine material and ashes obtained and is at least partially returned to the process again as oversized material . 
     
     
         14 . The method of  claim 1 , characterized in that the carbon-containing compounds, before being used in the countercurrent gasifier, are converted by agglomeration into particles having a particle size in the range between 2 mm and 300 mm. 
     
     
         15 . The method of  claim 1 , characterized in that in the vertical process chamber, between the top and the bottom, a differential pressure in a range of from 50 to 100 mbar is developed.