A microscopic study of the combustion residues of subbituminous and bituminous coals from Alberta, Canada

Relationships between the optical reflectance of coal blends and the microscopic characteristics of their cokes

“…Patrick et al, 1973;Qian et al, 1983;Patrick and Walker, 1991;Gentzis and Chambers, 1993) positive correlations between the amount of groups I, II and IV of coke particles and the reflectance values of coal blends were observed. The higher the mean reflectance of the coal blend, the greater the contribution of the group II particles with mosaic texture (Fig.…”

“…The relationships between basic parameters of parent coals and microtexture of their produced cokes have been extensively studied (e.g., Ammosov et al, 1957;Qian et al, 1983;Moreland et al, 1988;Patrick and Walker, 1991;Gentzis and Chambers, 1993;Jasieńko et al, 1997;Menendez et al, 1997). Gray (1976) established that coke consists of a binder phase and a filler phase.…”

Characterization of organic matter in dusts and fluvial sediments from exposed areas of downtown Prague, Czech Republic

“…Petrographic classification of chars (Tsai and Scaroni, 1987), fly ashes (Bailey et al, 1990), and gasification residues (Shibaoka et al, 1996), with some modifications (Gentzis and Chambers, 1993;Rosenberg et al, 1996;Zheng and Wang, 1996;Hower et al, 2005;Suárez-Ruiz et al, 2007) were used for evaluation of particles of chars. Petrographic composition of lignite and bituminous coal particles was determined by maceral analysis using the maceral classification established by Taylor et al (1998), ICCP (1998, and Sýkorová et al (2005).…”

“…Chars are solid products of thermal alteration of coal (Gentzis and Chambers, 1993;Elmquist et al, 2004) and other natural or synthetic organic materials (Wornat et al, 1994), and charcoal originates from remains of burned forest, peat, mires and degraded wood and other vegetation. Soot is micron and sub-micron particles formed at high temperatures from the condensation of hydrocarbons followed by growth and stacking of aromatic layers, which conglomerate into graphite-like structures, which are also sometimes described as micro-graphitic particles (Schmidt and Noack, 2000;Gelinas et al, 2001).…”

Influence of rank and macerals on the burnout behaviour of pulverized Indian coal

“…Low-rank inertinites can have better burning characteristics than high-rank vitrinites. The presence of different macerals and microlithotypes has been related to the type and morphology of pyrolysis chars, chars present in burnout residues, and fly ash (Chatterjee et al, 1987;Bailey et al, 1990;Bend et al, 1992;Gentzis and Chambers, 1993;Alvarez et al, 1997;Alonso et al, 2001). Image analysis technique has been used to identify the unreactive content in the coal, which has been subsequently linked with the formation of low-reactive unfused chars (Cloke et al, 1997(Cloke et al, , 2002(Cloke et al, , 2003.…”