Method for the Continuous Production of Synthesis Gas from Oil Sand and/or Oil Shale

Abstract

The invention relates to a method for the continuous obtention of synthesis gas by the direct gasification of carbon fractions contained in oil sands and/or oil shales in a vertical process chamber ( 2 ) having a calcination zone and an oxidation zone ( 6 ), in which the calcinated, fractions rich in carbon oxidize with oxygen-containing gas. The gaseous reaction products are withdrawn at the top of the vertical processing chamber ( 2 ) that has the shape of a vertical shaft furnace which is continuously flown through from the top to the bottom by a bulk material which itself is not oxidized. Oxygen-containing gas ( 10 ) is at least partially introduced beneath the oxidation zone, whereby the rising gas flow is facilitated. The bulk material is at least partially provided by the natural inert rock content in the oil sands and/or the oil shales. Added alkaline substances convert under reductive conditions the gaseous sulfur compounds, which were obtained at temperatures above 400° C. from the constituents of the oil sands and/or the oil shales, by chemical reaction into solid sulfur compounds which are at least partially discharged with the gaseous reaction products and are removed from the gas phase at temperatures above 300° C. by fine material separation ( 18 ).

1 . A method for continuous production of synthesis gas by direct gasification of carbon components, contained in oil sands and/or oil shales, in a vertical process chamber with a calcining zone and an oxidation zone, in which zone the calcined carbon-rich components oxidize with oxygen-containing gas, and the gaseous reaction products are drawn off at the top of the vertical process chamber, and the vertical process chamber is embodied in the form of a vertical shaft furnace, through which a bulk material, which itself is not oxidized, flows continuously from top to bottom, and the oxygen-containing gas is introduced at least partially below the oxidation zone, characterized in that the bulk material, furnished at least partially by the natural inert rock component of the oil sands and/or oil shale, which is converted in the vertical process chamber by chemical reaction with the alkaline substances at temperatures of over 400° C. into solid sulfur compounds by adding alkaline substances under reductive conditions; these solid sulfur compounds are partially carried away with the gaseous reaction products; and at temperatures above 300° C. they are removed from the gas phase by fine-material separation. 
     
     
         2 . The method of  claim 1 , characterized in that the oil sands and/or oil shale, before entering the vertical process chamber, is comminuted by means of mechanical energy to a particle size of less than 300 mm. 
     
     
         3 . The method of  claim 1 , characterized in that as the 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 calcining zone and/or are admixed with the oil sands and/or oil shale before entering the vertical process chamber. 
     
     
         4 . The method of  claim 3 , characterized in that the metal oxides, metal carbonates, and metal hydroxides contain elements of the alkaline earth metals and especially preferably contain calcium as a cation. 
     
     
         5 . 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 essential components of the resultant cleavage products containing oil and/or tar, which have a chain length of greater than C4, into carbon monoxide, carbon dioxide and hydrogen is performed at temperatures of above 400° C. 
     
     
         6 . The method of  claim 1 , characterized in that the water vapor is metered purposefully into the vertical process chamber and/or into the gas phase above the calcining zone, and/or is furnished in situ from the residual moisture of the oil sands and/or oil shale. 
     
     
         7 . 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 as solid material and/or as a suspension in water. 
     
     
         8 . The method of  claim 1 , characterized in that as the water, aqueous media from the oil sand exploitation process, for instance from the extraction of the crude bitumen, are used. 
     
     
         9 . The method of  claim 1 , characterized in that the flow speed of the gaseous reaction products drawn off at the top of the vertical process chamber amounts, as a result of suitable process control, to at least 10 m/s and thus the removal of the fine-granular alkaline substances and the solid sulfur compounds from the vertical process chamber via the gas phase is at least partially ensured. 
     
     
         10 . The method of  claim 1 , characterized in that the fine-granular alkaline substances are used in a quantitative ratio of at least 1 g per Nm 3  of resultant gaseous reaction products, as a result of which a total dust concentration in the gas phase of the drawn-off gaseous reaction products of at least 1 g of solids per Nm 3  is ensured. 
     
     
         11 . The method of  claim 1 , characterized in that the fine-material separation of the fine-granular alkaline substances and the solid sulfur compounds from the gas phase is effected via stationary filter surfaces, on the oncoming flow side of which a coating of the solid filtration material forms as a deep filtration layer, as a result of which a final intensive contact of the gaseous cleavage products with the fine-granular alkaline substances prior to the final fine-material separation is ensured, in order to cause a maximum amount of gaseous sulfur compounds to react with the alkaline substances. 
     
     
         12 . The method of  claim 1 , characterized in that the bulk material moving bed is formed partly by additional metering in of coarse material, to increase the flowability of the bulk material and/or its gas permeability, and the coarse material is admixed with the oil sands and/or oil shale before entering the vertical process chamber. 
     
     
         13 . The method of  claim 12 , 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 2 mm to 300 mm are used. 
     
     
         14 . The method of  claim 12 , 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. 
     
     
         15 . The method of  claim 1 , characterized in that the reductive overall conditions proceed at a total lambda of less than 0.5 through all the stages of the process chamber, and preferably 0.3 or less. 
     
     
         16 . The method of  claim 1 , characterized in that additional carbon carriers are admixed with the oil sands and/or oil shale before entering the vertical process chamber, in order to increase the concentration of exploitable carbon-containing components in the bulk material moving bed. 
     
     
         17 . The method of  claim 1 , characterized in that the oxygen-containing gas is delivered to the vertical process chamber in the form of pressure pulses, in order by these mechanical forces to contribute to loosening up and/or reinforcing the flow of the bulk material. 
     
     
         18 . The method of  claim 1 , characterized in that the synthesis gas produced is used at least partially as raw material for Fischer-Tropsch synthesis for producing hydrocarbons, such as fuels.