USN has done research on different methods that could be applied in the industry to determine the biomass fraction, such as the selective dissolution method (SDM). The method appears to be reliable, but is quite time and labour consuming. Hence the research group has developed a simplified method which utilizes readily available fuel characteristics (heating value, moisture content and ash content) to calculate the biomass fraction. The method is used by the Norwegian cement industry.
Ariyaratne, W.K.H., Melaaen, M.C. and Tokheim, L.-A.: "Determination of biomass fraction for partly renewable solid fuels", Energy, 70, No. 4, 465-472, 2014
Ariyaratne, H., Asgautsen, Ø., Melaaen, M.C., Eine, K. and Tokheim, L.A.: "Determination of Fossil Fraction of Refuse Derived Fuel by the Selective Dissolution Method in Calorific Value Basis: Development of Simplified Method", Fuel, 98, No. 8, 41-47, 2012