(93c) A New Fischer-Tropsch Technology for China

COMPS has been developing new ways of setting performance targets for plant performance (Patel et al 2005). This is done by using a new approach that allows one to analyse a process from a mass, energy and work integration point of view, namely complete process synthesis (ComPS). By doing this one is able to identify the performance target of the plant. This can be done at the very earliest stage of the synthesis of a process as the only information needed is simple thermodynamic information and temperature ranges at which processes must operate. This enables one to identify potential inefficiencies in plant performance in both the design phase as well as when analysing existing plants.

ComPS is illustrated by examining the Fischer-Tropsch Synthesis process. It is shown that a good measure of the performance of the plant is the carbon efficiency of the process. This can then be shown to be a measure of the mass, energy and work integration of the plant. Poor decisions at the flow-sheet generation stage and inefficiencies in general manifest themselves as extra carbon dioxide production. It is further shown that different flow-sheets have different target carbon efficiencies. This approach thus provides a method to choose between different flow-sheets at the earliest stage of plant design or as a method to look at upgrading current flow-sheets. The method is used to evaluate various alternatives and to synthesise a 100 000 tonne per annum Fischer-Tropsch demonstration plant that is to be built in China.

Current coal based FT technology is relatively inefficient in terms of carbon utilisation in that the ultimate target is 3.7 tons of CO2 produced per ton of liquid fuels. Real processes produce considerably more CO2, namely in the order of 7.4 tons. FT technology is also very capital intensive. It is shown that similar carbon efficiencies can be obtained using simpler flow-sheets which leads to a less capital intensive plant. Alternative new chemistries and other opportunities are explored that potentially offer large improvements in carbon efficiencies and hence a new greener generation of FT technology for China.

Patel, Bilal, Hildebrandt, Diane, Glasser, David, and Hausberger, Brendon. (2005) Thermodynamics Analysis of Processes. 1. Implications of Work Integration. Ind. Eng. Chem. Res. Vol. 44, 3529-3537