THE ENDOWMENT OF WILLIAM SPACKMAN TO THE FIELD OF COAL PETROLOGY

An early breakthrough in understanding the role of coal macerals in carbonization was achieved at Penn State under William Spackman using a hot-stage microscope equipped with a motion camera. The behavior of hand-picked macerals under various heating regimes dispelled the myth that the mix of these materials was of no consequence in utilization. Spackman collaborated with U.S. Steel scientists to develop a method of predicting the strength of coke produced from any given coal or blend from its petrographic composition. This predictive method, sometimes modified, quickly became widely used around the world by the coal and steel-making industries. To Spackman the paleobotanist it was apparent that the maceral vitrinite had originated from different plant tissues and organs. He believed that to group all of this material together as vitrinite, especially since it varied significantly in properties with rank, over-simplified coal’s petrographic composition. Therefore, he suggested a new classification system according to which different vitrinites within a single coal or between coals of different ranks were termed “vitrinoids”; the same concept would be applied to different fusinoids, resinoids, etc. For a while the Spackman terminology was in common use in North America but is now obsolete. The rapid success of the new approach to understanding coal composition and behavior in carbonization initially resulted in some misconceptions. For example, the normal distribution of the dominant vitrinite’s reflectance was interpreted as being due to a mixture of different vitrinoid “V-types,” each with different carbonization potentials. Later, however, it became recognized that there may indeed be different populations of vitrinite within a single coal resulting from original botanical or diagenetic factors.

Due to the energy crisis of the 1970’s the Coal Research Section spearheaded a multi-departmental program directed towards the gasification and liquefaction of coal. The observations revealed potential problems and advantages to be gained in hydrogenation processing. William Spackman’s legacy of applying the quantification of the basic ingredients of peats, coals and dispersed organics to understand their origins and industrial potentials and behaviors has been extended to rocks of all ages.