PhD Thesis - Energy Systems Research Unit - University of Strathclyde

Figure 2.7 The Ethanol Production Process [75]
2.5.5 Steam Reforming of Methane to Hydrogen
The steam reforming process produces hydrogen, carbon monoxide and carbon
dioxide by the reaction of methane and steam. The usual feedstock for this
process is natural gas, but the methane produced from gasification, anaerobic
digestion or from landfill sites can also be used. This reaction requires no
significant electricity input, but heat is required to produce the steam, and the
reaction, in reality, only goes to around 90% completion. Well-proven
technology exists on a range of scales for this continual process [82,83]. As this
process is often used in conjunction with other plant, significant use can be
made of excess heat to reduce the energy requirements.
2.5.6 Catalytic Synthesis of Methanol
The biogas produced by gasification, anaerobic digestion or from landfill sites
can also be processed to methanol via catalytic conversion. If the biogas has a
high methane content, this is first converted to hydrogen, carbon monoxide and
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