Advanced Characterization of Biofuels for Combustion and Gasification Plants

Abstract

Detailed information on the biofuels is an essential requirement for the prediction of plant efficiency, carbon in ash, pollutant emissions, surface deposition and corrosion, in thermochemical processes. A fuel- specific comprehensive characterization is required to design, operate and model combustion, oxy-firing and gasification plants. At IFRF it couples fundamental analyses with advanced tests in the Isothermal Plug Flow Reactor (IPFR), which allows high temperature and heating rate, under programmed gaseous environments (N2, O2, CO2, H2O). The aim of this work is to: define the experimental procedures for testing biomass fuels in the IPFR; provide significant results of the recent experimental campaigns on biomass fuels; extrapolate the prerequisites and principles that could be in common with other test facilities (in the frame of the BRISK project) for an advanced characterization. Particular attention is devoted to the qualification of the system and procedures used. Different sources of uncertainty (due to diagnostic limitations, segregation phenomena, fuel heterogeneity) affecting the operating parameters and test outputs (e.g., reaction conversion, obtained with the ash tracer method) are studied. The improvements in the experimental apparatus and procedures, as well as the support of CFD assisted diagnostics (e.g., to estimate the effective thermal history of the particles inside the reactor) have helped in quantifying and reducing the experimental uncertainties. The aim is to provide qualified data for the prediction of operational/design parameters for industrial-scale thermochemical systems. Uniform and reliable data will be finally inserted into the IFRF online Solid Fuel DataBase (SFDB).