Perennial grasses offer energy production opportunities, as many species produce high outputs of dry mass per area per year– even higher than established tree crops for energy use. Phyllostachys aurea is a running bamboo recognized worldwide as an invasive species with ornamental properties. Although Phyllostachys aurea monocultures pose a threat to surrounding native vegetation if it is not well-managed, the spread can be contained with relatively simple measures. It offers an unprecedented growth rate, high tolerance for diverse soil types and climate/altitude conditions and short time rotation. Phyllostachys aurea low energy density and other undesirable properties for bioenergy production can be drastically improved by treatments like pelleting, briquetting and torrefaction. Phyllostachys aurea raw biomass has distinguished energy parameters among grasses such as low ash content, similarly to woods like Eucalyptus sp., although it forms pellets with low mechanical durability. Torrefaction as pretreatment could increase pellet mechanical durability, therefore improving overall pellet quality. The main purpose of this study is to assess the potential use of raw and torrefied culms of Phyllostachys aurea to produce fuel pellets and briquettes with ISO 17225-6, ISO 17225-7 and ISO 17225-8 quality requirements. The raw material was torrefied at 220 °C temperature before pelleting and briquetting. Raw and torrefied biomass went to moisture adjustments for pellet production on a pilot scale. Densified products were then characterized for physical, chemical and energy properties recommended by ISO standards. Result analysis allows for improving Phyllostachys aurea pellet and briquette production protocols by identifying operational parameters and input conditions required to obtain densified fuels with commercial quality.

Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 657-661