High volatile bituminous coal

Bituminous class class of rank consisting of high-volatile C bituminous coal, high-volatile B bituminous coal, high-volatile A bituminous coal, medium-volatile bituminous coal, and low-volatile bituminous coal. 

Low-volatile bituminous coal Medium-volatile bituminous High-volatile A bituminous coal High-volatile B bituminous coal High-volatile C bituminous coal... 

ASTM class cation, group name Meta an- thra- cite Anthracite Semianthradte Low-volatile bituminous coal Medium-volatile bituminous coal High-volatile A bituminous coal -[ -volatile B bituminous coal High-volatile C bituminous coal and subbituminous A coal Subbituminous B coal ... 

Fig. 11. Effect of coal rank on furnace sizing (constant heat output) (82), where W = width, D = depth, and h and H are the heights indicated. A represents medium volatile bituminous B, high volatile bituminous or subbituminous C, low sodium lignite D, medium sodium lignite and E, high...

An implication of Cudmore s data (10) for the sub-bituminous and high volatile bituminous coals is that the semi-fusinite as such appears to contribute little to the conversion products, otherwise the apparent dependence of yield on the vitrinite (+ exinite) content would not be so linear. 

The general appearance in the electron microscope of an ultrathin section of a heterogeneous area of dull coal (high volatile A bituminous) is illustrated in Figure 1. Components readily identifiable as vitrinite, exinite, and granular micrinite are indicated. Distinguishing the other variously shaded areas is not so positive, but identification can usually be established from shape, density, and association. 

We have found that scattering patterns like Curve 1 in Fig. 2 are typical of lignites and of some sub-bituminous and high-volatile bituminous coals. 

Thermal coals Coals used as a fuel, mainly for power generation. These are lower-rank coals (high volatile bituminous, subbituminous, and liginites). 

Bituminous is the most abundant rank of coal. It accounts for about 50% of the coal produced in the United States. Bituminous coal has a carbon content of between 77% and 87% on a dry ash-free basis and a heating value that is much higher than lignite or subbituminous coal. On the basis of volatile matter content, bituminous coals are subdivided into low-volatile bituminous, medium-volatile bituminous, and high-volatile bituminous. Bituminous coal is often referred to as soft coal but this designation is a Layman s term and has httle to do with the hardness of the coal. 

Figure 3.10 shows the degasification process for hard coal belonging to the middle coal rank (medium volatile bituminous (A), high volatile bituminous (B)) at a heating rate of 2 K/min. 

Properties. A high volatile western Kentucky bituminous coal, the tar yield of which by Fischer assay was ca 16%, gave a tar yield of ca 26% at a pyrolysis temperature of 537°C (146—148). Tar yield peaked at ca 35% at 577°C and dropped off to 22% at 617°C. The char heating value is essentially equal to that of the starting coal, and the tar has a lower hydrogen content than other pyrolysis tars. The product char is not suitable for direct combustion because of its 2.6% sulfur content. 

A yield comparison between the products of the SRC-I and SRC-II processes operating on a high volatile Kentucky bituminous coal is... 

High-volatile A bituminous coal — 69 31 — 32.6 — 14,0005 — Commonly agglomerating ... 

Low volatile bituminous coal and high volatile anthracite coal 11,000-14,000... 

Much work has been described in the literature on determining which chemical and physical features distinguish coals in terms of reactivity or hydrogenation potential [21]. Coal rank is certainly one of the featiues as shown by the difference between WVGS 13421, which is a medium-volatile bitummous coal, and the lower rank WVGS 13423, which is a high-volatile A bituminous coal. 

Low volatile bituminous coal and high volatile anthracite coal Subbituminous coal Lignite Coke and coke breeze Wood Bagasse (dry) 11.000- 14,000 9.000- 11,000 7.000- 8,000 12.000- 13,000 8.000- 9,000 7.000- 9,000... 

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