Relating to coal to liquid processes

Abstract

A method of increasing the hydrogen/carbon monoxide (H 2 /CO) ratio in a syngas stream derived from a carbonaceous fuel including coal, brown coal, peat, and heavy residual oil fractions, preferably coal. The fuel-derived syngas stream is divided into at least two sub-streams, one of which undergoes a catalytic water shift conversion reaction. The so-obtained converted sub-stream is combined with the non-converted sub-stream(s) to form a second syngas stream with an increased H 2 /CO ratio. The method of the present invention can provide a syngas with a H 2 /CO ratio more suitable for efficient hydrocarbon synthesis carried out on a given catalyst, such as in one or more Fischer-Tropsch reactors, as well as being able to accommodate variation in the H 2 /CO ratio of syngas formed from different qualities of feedstock fuels.

What is claimed is: 
     
         1 . A process for the preparation of hydrogen-enriched fuel-derived syngas derived from a carbonaceous fuel, comprising:
 providing a fuel-derived syngas stream;   dividing the fuel-derived syngas stream into at least two sub-streams;   letting one of the at least two sub-streams undergo a catalytic water shift conversion reaction followed by passing the converted stream through a carbon dioxide/hydrogen sulphide removal system to obtain a converted and cleaned sub-stream;   passing the other stream(s) through a carbon dioxide/hydrogen sulphide removal system to obtain a cleaned non-converted sub-stream(s);   combining the obtained converted and cleaned sub-stream with the cleaned non-converted sub-stream(s) to form a hydrogen-enriched fuel-derived syngas stream having an increased H 2 /CO ratio of between 1.4 and 1.95.   
     
     
         2 . The process of  claim 1 , wherein the H 2 /CO ratio in the fuel-derived syngas stream is less than 1. 
     
     
         3 . The process of  claim 1 , wherein the H 2 /CO ratio in the hydrogen-enriched fuel-derived syngas stream is greater than 1.5. 
     
     
         4 . The process of  claim 1 , wherein the H 2 /CO ratio in the hydrogen-enriched fuel-derived syngas stream is in the range 1.6-1.9. 
     
     
         5 . The process of  claim 1 , wherein the H 2 /CO ratio in the hydrogen-enriched fuel-derived syngas stream is in the range 1.6-1.8. 
     
     
         6 . The process of  claim 1 , wherein the fuel-derived syngas stream is divided into two sub-streams. 
     
     
         7 . The process of  claim 6 , wherein the ratio of fuel-derived syngas stream divided into the shift conversion sub-stream and other sub-stream is in the range 70:30 to 30:70 by volume. 
     
     
         8 . The process of  claim 1 , wherein a portion of the converted sub-stream is used for manufacture of hydrogen. 
     
     
         9 . The process of  claim 8 , wherein the portion of the converted sub-stream used for the manufacture of hydrogen is less than 10% by volume. 
     
     
         10 . The process of  claim 8 , wherein the portion of the converted sub-stream used for the manufacture of hydrogen is approximately 1-7% by volume. 
     
     
         11 . The process of  claim 1 , wherein the carbon dioxide/hydrogen sulphide removal system uses a physical solvent process. 
     
     
         12 . The process of  claim 11 , wherein the physical solvent process comprises a rectisol process. 
     
     
         13 . The process of  claim 1 , wherein the carbonaceous fuel includes one or more of coal, brown coal, peat, and heavy residual oil fractions. 
     
     
         14 . The process of  claim 1 , wherein the carbonaceous fuel includes coal. 
     
     
         15 . Syngas whenever prepared by the process of  claim 1 . 
     
     
         16 . A Fischer-Tropsch process using the syngas of  claim 15 . 
     
     
         17 . The Fischer-Tropsch process of  claim 16 , wherein the Fischer-Tropsch process is a multi-stage Fischer-Tropsch process. 
     
     
         18 . The Fischer-Tropsch process of  claim 17 , wherein the catalytically shifted syngas sub-stream is used as feed for a first of the multi-stage Fischer-Tropsch process and as an additional feed for a further stage in the Fischer-Tropsch process. 
     
     
         19 . The Fischer-Tropsch process of  claim 12 , wherein the Fischer-Tropsch process is a two-stage process. 
     
     
         20 . A hydrocarbonaceous product, whenever produced by the Fischer-Tropsch process of  claim 12 . 
     
     
         21 . A hydrocarbonaceous product including any product made by hydroconversion of the hydrocarbonaceous product of  claim 20 . 
     
     
         22 . A process for hydrocracking of a hydrocarboneceous product, comprising
 (a) providing a hydrocarbonaceous product obtained by performing a Fischer-Tropsch process on a hydrogen-enriched fuel-derived syngas derived from a carbonaceous fuel, obtained from a process wherein:   a fuel-derived syngas stream is provided;   the fuel-derived syngas stream is divided into at least two sub-streams;   one of the at least two sub-streams undergoes a catalytic water shift conversion reaction followed by passing the converted stream through a carbon dioxide/hydrogen sulphide removal system to obtain a converted and cleaned sub-stream;   the other stream(s) is (are) passed through a carbon dioxide/hydrogen sulphide removal system to obtain a cleaned non-converted sub-stream(s);   the obtained converted and cleaned sub-stream is combined with the cleaned non-converted sub-stream(s) to form a hydrogen-enriched fuel-derived syngas stream having an increased H 2 /CO ratio of between 1.4 and 1.95;   (b) using a portion of the converted sub-stream from (a) to produce hydrogen;   (c) hydrocracking the hydrocarbonaceous product as provided in (a) using the hydrogen as provided in (b) for the cracking stream.   
     
     
         23 . The process of  claim 22 , wherein the carbonaceous fuel includes one or more of coal, brown coal, peat, and heavy residual oil fractions. 
     
     
         24 . The process of  claim 22 , wherein the carbonaceous fuel includes coal. 
     
     
         25 . A syngas derived from a carbonaceous fuel, wherein the hydrogen/carbon monoxide (H 2 /CO) ratio has been increased according to a method wherein
 the fuel-derived syngas stream is divided into at least two sub-streams;   one of which undergoes a catalytic water shift conversion reaction where after the converted stream passes through a carbon dioxide/hydrogen sulphide removal system;   the other stream(s) is (are) passed through a carbon dioxide/hydrogen sulphide removal system; and   the obtained converted and cleaned sub-stream is combined with the cleaned, non-converted sub-stream(s) to form a syngas stream having an increased H 2 /CO ratio of between 1.4 and 1.95.   
     
     
         26 . The process of  claim 25 , wherein the carbonaceous fuel includes one or more of coal, brown coal, peat, and heavy residual oil fractions. 
     
     
         27 . The process of  claim 25 , wherein the carbonaceous fuel includes coal.