Predicting bed agglomeration tendencies for biomass fuels fired in FBC boilers: A comparison of three different prediction methods

In this paper a comparison between three different types of techniques to p redict the bed agglomeration tendency of a FBC (fluidized-bed combustor) wa s performed. The three techniques were the standard ASTM ash fusion test, a compression strength based sintering test and a lab-scale combustion test. The tests were performed on 10 different types of biomasses. The results s howed significant differences in the predicted bed agglomeration temperatur es depending on which technique was used. The ASTM standard ash fusion test generally showed 50-500 degrees C higher temperatures than the sintering t ests or the lab-scale FBC combustion tests. The sintering test showed, in f ive cases, 20-40 degrees C lower sintering temperatures than what was detec ted as the bed agglomeration temperature with the lab-scale FBC. In two cas es, a significantly lower sintering temperature than the bed agglomeration temperature was detected, and in three eases, a significantly higher sinter ing temperature was detected than the bed agglomeration temperature. The de tailed results and their relevance is discussed in the paper.