Process design of Synthetic Natural Gas (SNG) production using wood gasification

The process design of a 10–20 MWth Synthetic Natural Gas (SNG) production process from wood has been performed. Combining process modelling and process integration techniques, this study proceeds via the following stages: • thermodynamic modelling: mass, energy balances and simulation of the wood gasification, the methanation and the purification units; • process integration that identifies the energy saving opportunities and prepares a thermo-economic optimization. This work demonstrates that the process can transform wood into pipeline quality methane with a thermal efficiency of 57.9% based on the Lower Heating Value (LHV). The process integration study shows that the heat surplus of the process can be used to almost satisfy the mechanical work required by the process; only 7% of the mechanical needs should come from an external source.