Synthesis gas ("syngas"), a gaseous mixture comprised mostly of H2 and CO, is produced by the steam reforming or partial oxidation of hydrocarbon feedstocks or a combination of both processes (tandem reforming). Syngas is utilized in the production of an array of chemicals and energy products including but not limited to methanol, ammonia, synthetic fuel (Fischer-Tropsch products), electricity, steel-making, synthetic natural gas (SNG), and hydrogen. The H2/CO ratio required for downstream product generation is adjustable with operational modifications and additional gas shift processes.
In general, gaseous and light oil hydrocarbon are converted into syngas using catalytic steam-reforming or partial oxidation. Heavier oil and solid feedstocks like refinery by-products (residual oil, asphaltene, and petroleum coke) and coal are converted into syngas through gasification reactions in a reducing environment. Generally, the oil/solid based syngas contains unwanted compounds such as hydrogen sulfide, cyanides, and ammonia. Downstream processes are used to remove the unwanted compounds and to adjust the H2/CO ratio to its desired amount. These water-gas-shift reactions, acid gas removal technologies like RECTISOL® or amine-based designs, pressure-swing-adsorption and membrane separation can all be employed as needed.