Exergoenvironmental analysis of methanol production by steam reforming and autothermal reforming of natural gas

Methanol is one of the most important chemicals serving as a base for a range of synthetic fuels and variety of other chemical derivates. Steam reforming and autothermal reforming of natural gas represent the major technologies used for syngas production in indirect low pressure methanol synthesis routes. Further process development is driven by technical and economic aspects, while environmental aspects often fade into the background. In this paper methanol production processes using steam reforming and autothermal reforming are investigated from the viewpoint of an exergoenvironmental analysis. The processes feature a coproduction of electricity for high efficiency. The pollutant formation within the chemical conversion units, particularly within the reformer and the furnace, reduces the environmental impact associated with the overall system. The environmental impact of generated methanol and electricity is calculated respectively as 156.4 mPt/kg and 98.2 mPt/MWh for the steam methane reforming process and has values of 134.0 mPt/kg and 71.3 mPt/MWh for the autothermal reforming process.