Thermo-catalytic reforming pyrolysis of ensiled Saccharina latissima dominated macroalgal pellets for bioenergy production

Marine macroalgae is a biomass resource for the manufacture of fuels and chemicals, which can be sustainably harvested from seaweed farms or from man-made structures where it accumulates as a biofouling organism.However, in temperate regions farmed macroalgae can only be harvested between late Spring and early Summer, limiting year-round availability.Here we show that a conventional grass ensilage procedure preserves Saccharina latissima dominated biomass on the tonne scale for 30 months, enabling year-round use of this biomass.Following processing, the resulting dried and pelletised ensiled macroalgae material was subject to Thermo-Catalytic Reforming™, comprising sequential pyrolysis (450 • C) and either dry or steam catalytic reforming (700 • C) processes.Both processing methods produced a mixture of bio-oil (1.6-1.9 wt%) and hydrogen-rich permanent gases (30.9-31.1 wt%) with higher heating values of 34.8-35.4MJ/kg and 18.0-24.2MJ/m 3 , respectively, together with char (45.5-48.5 % wt).The permanent gases can be used directly for heat generation, while hydro-treatment of the bio-oil would afford a material that can be blended with traditional transport fuels.This work demonstrates that if operated at scale, the combined harvesting, ensilaging and Thermo-Catalytic Reforming™ of preserved macroalgal biomass offers a year-round decentralised energy resource.