Page 242 - Advanced Mine Ventilation

220 Advanced Mine Ventilation

Btu Less Than 14,000 13,000 11,500 11,500 10,500 9,500 8,300 6,300
Limits, (Moist a e e e e e e

Value Pound Mineral-MattereFree Basis) Than

Calorific per or Equal Greater e e e e e 14,000 b 13,000 b {11,500 {10,500 10,500 9,500 8,300 6,300 e value. 1-27-29.

% Less calorific 1968.
Limits, Mineral- Basis) or of regardless Inc.;

Matter (Dry, MattereFree Equal Than 2 8 14 22 31 e e e e e e e e carbon, Engineers,

Volatile Greater Than e 2 8 14 22 31 e e e e e e e coal. the of fixed to Petroleum and

surface according Metallurgical
% Less Than the
Limits, Mineral- Basis) e 98 92 86 78 69 e e e e e e e on water classified Mining,

Carbon (Dry, MattereFree or Than visible be shall of Institute

Fixed Equal Greater including basis
92
98
69
78
86
e
e
e
e
e
e
e
e
not American
but mineral-matterefree The
coal bitumi- coal coal coal moisture
Rank coal coal coal A B C dry, preparation.
by coal B C inherent the Coal
Coals Metaanthracite Anthracite Semianthracite Low-volatile Medium-volatile High-volatile A High-volatile bituminous High-volatile bituminous Subbituminous Subbituminous Subbituminous A B natural on DR.
of Group 1. 2. 3. 1. 2. 3. nous 4. 5. 1. 2. 3. Lignite 1. Lignite 2. its carbon fixed Mitchell
Classification containing coal more or JW, Leonard
13.4 Anthracitic Bituminous III.Subbituminous Lignitic to refers 69% having from
Table Rank I. II. IV. a Moist b Coals Adapted