In-situ investigations via confocal video-processing analyses of mullite vs. alumina refractories for application to biomass-fueled gasifiers

Abstract

The National Energy Technology Laboratory (NETL) targets modular gasifiers that can accommodate diversified carbon feedstock such as biomass and waste plastics. Towards this goal, it is necessary to better understand interactions of candidate refractory ceramics with feedstock ashes. In this work, confocal scanning laser microscopy in conjunction with a variety of image-processing techniques was utilized to assess these interactions in-situ with biomass ashes. We found that various ash components followed different timelines. A key factor which further affected these timelines was proximity to chemical and/or topological boundaries, including but not limited to other ash or slag, pores, cracks, crevices, grain boundaries, and matrix-aggregate boundaries. Alignment techniques such as Scale-Invariant Features Transformation (SIFT) enabled increased comparability of features as ZY or XZ planes could be aligned fully onto a consistent location of an ash. In tandem with thresholding techniques and assessment of useful features, SIFT allows potential for future rapid analyses of otherwise difficult to quantify videography.