A Determination Method for the Biomass Lower-Calorific-Value-Based Blending Ratio in Co-Firing Power Plants

Abstract

The accurate measurement of the biomass lower-calorific-value-based blending ratio (BLBR) is the premise and key to scale development of the power generation technology from co-firing of biomass and coal. However, existing determination methods of BLBR are less accurate, which has impeded the scale utilization of the co-firing technology of biomass and coal. To accurately determine the BLBR, this research proposed a flue gas sampling system suitable for determining BLBR through 14C quantitative analysis and established a medium-scale experimental platform for BLBR determination. In addition, predictive models for the lower calorific values of coal and biomass fuels were built and the BLBR calculation model for co-firing power plants was deduced. Furthermore, experimental verification of the BLBR determination was also conducted. The results show that the lower calorific values of coal and biomass fuels are highly linearly positively correlated with the carbon content. The relative errors of the established prediction models for lower calorific values of biomass and coal are separately lower than 5% and 8%. The results indicate that the proposed BLBR determination method is accurate.