Firing tests of biocoal

Copyright © 2014 by ASME. As part of PGE-EBC-MTU collaboration of the testing program to fire up to 100% of biocoal in the 600 MW Boardman boiler we produced samples from the seven biomass feedstock: Arundo Donax (AD), wheat waste, corn waste, woody hybrid poplar, and bark from hybrid poplar, woody pine, and bark from pine. The various samples of biocoal were tested in a combustion chamber with the following results: (1) Biocoal was fired and burned providing temperature and gas concentration profiles similar to coal. (2) NOx emission from all biocoal originating from any type of biomass feedstock was found to be significantly lower than that from coal burning. (3) SOx emissions was found to correlate directly to sulfur content in the plant minerals, which is very small for all types of biomass tested. (4) Fouling was quite low for all biocoal tested, such that it can be handled with an optimized water cannons procedure. (5) Minerals in the biocoal were found to segregate from the carbon particles which means that slagging propensity can be predicted by the common slagging indices. (6) Carbon cycle analysis revealed significant reduction of CO2 when using these biomass feedstock types, particularly the bark types