Wärtsilä has been awarded the order to supply a biogas liquefaction plant that will produce fuel for public transport vehicles, mainly in Norway. The Wärtsilä plant will be installed at the paper mill in Skogn, Norway and will convert the cleaned biogas from fishery waste and residual paper mill slurry into liquid fuel. The liquid will be cooled to minus 160°C and stored in insulated tanks. The system has been specially designed to liquefy small methane-based gas streams. This novel technology is based on readily available, well proven components but features a highly advanced process design and control system. The environmental benefits of delivering renewable liquid biogas fuel are enhanced by the fact that sulphur oxide (SOx) and particle emissions are virtually eliminated, while any released CO2 has zero environmental impact since it is part of the existing circulatory CO2.
Having the biogas as cryogenic liquid, rather than as compressed gas makes it a viable fuel for heavy vehicles since sufficient energy can be stored onboard.
Text by Wärtsilä