Radiocarbon Determination of the Carbon-Based Biomass Blending Ratio by Analysing Flue Gas Emitted from Coupled Combustion

The determination of carbon-based biomass blending ratio was a prerequisite for the large-scale development of the coupled combustion technology of biomass and coal. In this study, the experimental system of the radiocarbon method to detect the carbon-based biomass blending ratio by analyzing the flue gases produced during coupled combustion was built, and the calculation model of the carbon-based biomass blending ratio was proposed, and the accuracy and precision of the radiocarbon method were evaluated. The results showed that there was a good linear relationship between the 14C concentration of CO2 samples and biogenic fractions in flue gas. The application of the new calculation model improved the accuracy of the 14C determination method, and the relative error increased as the carbon-based biomass blending ratio decreased in the 14C method: the minimum relative error of the carbon-based biomass blending ratio with carbon-based assay was 15.16%,12.21%, 9.61%, 7.96% and 3.13% when considering coal and air simultaneously in AMS analysis. This further validated the 14C determination method as an accurate method for identifying the carbon-based biomass blending ratio in biomass and coal coupled combustion.