63008300

Lignite B

<6300

a Calculated on dry, mineral-matter-free coal. Correction from ash to mineral matter is made by means of the Parr formula: mineral matter = 1.08[percent ash + 0.55(percent sulfur)]. Ash and sulfur are on a dry basis.

bCalculated on mineral-matter-free coal with bed moisture content.

cCoals with heating values between 10,500 and 11,500 Btu/lb are classified as high volatile C bituminous if they possess caking properties or as subbituminous A if they do not. Source: Berkowitz, N., An Introduction to Coal Technology, Academic Press, New York, 1979. With permission.

a Calculated on dry, mineral-matter-free coal. Correction from ash to mineral matter is made by means of the Parr formula: mineral matter = 1.08[percent ash + 0.55(percent sulfur)]. Ash and sulfur are on a dry basis.

bCalculated on mineral-matter-free coal with bed moisture content.

cCoals with heating values between 10,500 and 11,500 Btu/lb are classified as high volatile C bituminous if they possess caking properties or as subbituminous A if they do not. Source: Berkowitz, N., An Introduction to Coal Technology, Academic Press, New York, 1979. With permission.

coal is described as being a certain rank, then an estimate of some properties can be made; for example, if the coal is classified as subbituminous/lignitic or anthracitic, then it would not be considered for certain applications, such as for coke production.

International Classification/Codification Systems

Because of the increasing amount of coal trade in the world, the ECE Coal Committee developed a new classification system in 1988 for higher rank coals [1]. A shortcoming of the original international system was that it was primarily developed for trading Northern Hemisphere coals, which have distinctly different characteristics than those from the Southern Hemisphere (e.g., Australia and South Africa). As trade of Southern Hemisphere coals increased, it became apparent that a new classification system was needed. This new system, which in reality is a system of codes, is better known as the Codification System. The Codification System for hard coals, combined with the International Organization for Standardization (ISO) Codification of Brown Coals and Lignites (which was established in 1974), provides a complete codification for coals in the international trade. The ISO Codification of Brown Coals and Lignites is given in Table 1-2 [1]. Total moisture content of run-of-mine coal and tar yield (i.e., determination of the yields of tar, water, gas, and coke residue by low-temperature distillation) are the two parameters coded. The ECE International Codification of Higher Rank Coals is much more complicated and is provided in Table 1-3. Eight basic parameters define the main properties of the coal, represented by a 14-digit code number. The codification is commercial; includes petrographic, rank, grade, and environmental information; is for medium- and high-rank coals only; is for blends and single coals; is for raw and washed coals; and is for all end-use applications [1]. The major drawback of this system is that it is complicated.

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