This research examines the use of hydrothermal liquefaction (HTL) process for a treatment of
biomass industrial waste. Brewer’s spent grain (BSG) is a source of lignocellulose that has a potential to be used for chemicals and fuels production, thereby reducing the reliance on fossil sources. There are relatively few investigations on using BSG in this system; hence, the
development of new techniques to valorise this agro-industrial waste is of a great interest as BSG is available in large quantities throughout the year.Two modes of HTL have been
investigated to determine the effects of using the BSG with high moisture content. The first
mode used the BSG as received without pre-treatment while the second mode used the dried
BSG mixed with pure water. The BSG conversion, water-soluble oil (WSO) yield and liquid
product generation were measured for both modes. The liquid products were also analysed to
determine the types and concentration of valuable products obtained via HTL. The
characterisation of the BSG reveals that the moisture content of the BSG is 74.7wt.% while the
FTIR spectra confirms the presence of cellulose, hemicellulose and lignin in the BSG. In
addition, the comparison between the two HTL modes indicates that the direct HTL gives better
BSG conversion, higher WSO yield and higher valuable products concentration. Therefore, it
is concluded that BSG has a high potential to be converted into valuable products via direct
HTL without pre-treatment. This opens a new opportunity for a sustainable alternative to waste
valorizatio
