MTI uses computer-controlled scanning electron microscopy (CCSEM) to determine the size, composition, abundance, and association of mineral grains in prepared coal, biomass, and petroleum-coke samples. With this information, we can assess the behavior of the mineral grains during combustion or gasification. CCSEM analysis can also help us predict impacts of fuel properties on wear of system components, slag flow, fouling of heat exchangers, fine-particle collection, and ash handling.
With automated CCSEM, MTI analyzes fuel sample cross-sections utilizing backscattered electron imaging (BEI) combined with automated particle recognition and chemical analysis. This method allows us to determine the composition, size, and abundance of mineral types. A typical BEI of a coal cross-section is shown below.
The automated CCSEM method allows up to 3,000 mineral grains to be characterized. Using the compositional data, we can classify mineral particle types based on composition of standard minerals.
See below for an example of CCSEM output for a subbituminous coal:
Our method of CCSEM analysis is illustrated below: