Integration opportunities for substitute natural gas (SNG) production in an industrial process plant

Paper in proceeding, 2012

The integration opportunities for SNG production based on thermal gasification of lignocellulosic biomass in one of the production plants currently importing natural gas for further processing to speciality chemicals was studied. To solve material and energy balances, the SNG process was modeled in Aspen Plus. Three opportunities for SNG process heat recovery was studied, i.e., the steam production potential from the SNG process excess heat, the electricity production potential by maximizing the heat recovery in the SNG process without additional fuel firing, and the electricity production potential with increased steam cycle efficiency and additional fuel firing. About 217 MwLHV of woody biomass were required to substitute the site's natural gas demand with SNG. There is a potential to recover heat from the SNG process to completely cover the site's net steam demand or to produce enough electricity to cover the demand of the SNG process. There is also a possibility to fully exploit the heat pockets in the SNG process Grand Composite Curve resulting in an increase of the steam cycle electricity output. This is an abstract of a paper presented at the CHISA 2012 - 20th International Congress of Chemical and Process Engineering and PRES 2012 - 15th Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction