Abstract

               Hydrogen production is essential to any coal-to-liquids process. Hydrogen is currently made from hydrocarbons using the water gas shift. This strategy results in a large amount of carbon dioxide emissions. With an alternative source of hydrogen, coal-to-liquids projects will not emit significant quantities of carbon dioxide.  This paper investigates several ways to reduce carbon dioxide emissions by making hydrogen from both water splitting and hydrocarbon steam reforming, reducing the use of the water gas shift reaction. The scheme presented in this paper uses an indirect coal-to-liquids process employing the Fischer-Tropsch reaction. (Figure 1 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003100380030003800380031003400340035000000 )

Figure  SEQ Figure \* ARABIC 1  An Indirect Coal-to-Liquids Flow Scheme

               The modified process uses high temperature (900°C) heat from a nuclear energy source (Pebble Bed Modular Reactor) for water-splitting in the Hybrid Sulfur process and in the steam-hydrocarbon reforming process to produce hydrogen and a to supply the heat for the endothermic reactions.   This nuclear alternative (Figure 2 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003100380030003800380031003600370038000000 ) significantly reduces the emission of carbon dioxide while increasing the production of liquid fuels from the available carbon feeds.  The value of hydrogen produced in this way will be estimated for each scheme and the major economic drivers identified.

Figure  SEQ Figure \* ARABIC 2  Coal-to-liquids Process Using Alternative Hydrogen Sources