Characterization describes what a fuel is and how it can be effectively used. Since the establishment of our Coal Services Group in the early 1970s, Hazen has developed extensive capabilities for solid-fuels analysis, characterization, research, and process development. Many of the characteristics of coal or other fuels are determined using ASTM procedures or standard analytical methods for fuels. These include proximate and ultimate analyses, trace metal content, ash, ash fusion temperature, and materials-handling Ash Fusion Furnace characteristics that may have an impact on commercial application, e.g. flowability, bulk density, bridging, dusting, etc.
We have developed many specialized characterization tests for fuels and fuel additives, such as determining the "self heating" tendency of upgraded low-rank coals, evaluating various fuels for potential fugitive emissions, and determining the effect of additives on emissions and ash properties. Our experienced staff can determine how the composition of the mineral matter in a fuel will affect combustion performance (slagging and fouling) as well as the waste-handling characteristics and leachability of the ash. Hazen's Mineralogical Laboratory has the equipment, procedures, and staff for the characterization of raw fuels, ashes, slags, and partially burned residues. We use optical microscopy, scanning electron microscopy, and QEMSCAN analyses to examine the fine structure of fuels and the nature of contaminants. A fully equipped inorganic analytical laboratory is vital for determining major elements and trace metals in fuels, and ours has performed millions of analyses. These investigative methods are also used in the study of fuels other than coal, for instance oil shale and tar sands. The reliability and usefulness of modern characterization techniques are limited more by the validity of sampling methods and sample preparation than by the accuracy of laboratory procedures. Hazen has had extensive experience in sampling all types of fuels, large and small stockpiles of coal, unit trains, and power plant feeding systems. We have also developed unique methods for sampling and characterizing unusual fuels such as stockyard animal refuse, corncobs, tar residues, municipal wastes, wood byproducts, and grasses.