论文信息 - Difficulties with Standard Tests to Predict Shipping Hazards with Coals and Carbons

Difficulties with Standard Tests to Predict Shipping Hazards with Coals and Carbons

STANDARD TESTS TO determine the shipping safety of coals and carbons [1,2] make use of a 10 cm x 10 cm x 10 cm cubic container of sample in an air oven at 140 ° C. Ignition denotes an unsafe material for shipping in a 3 m x 3 m x 3 m shipping hold, whilst failure to ignite signifies that the material may safely be shipped in such a size of hold. This is on the basis that, according to the Frank-Kamenetskii model of thermal ignition [3] criticality in a 10 cm cube at 140 ° C (413 K) is equivalent to criticality at 38 ° C (311 K) in a 3 m cube. This is so provided that an activation energy of 77 kJ mol-I applies [4]. The present author has recently been examining a German low-rank coal in oven heating experiments with special reference to ignition times-an aspect of the thermal behaviour not considered in the standard tests-and results will be contributed to the literature in due course. In this paper attention is drawn to ignition times expected from

J. C. Jones | J.C. Jones

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[3] J. C. Jones. Combustion Science: Principles and Practice , 1994 .

[4] J. Jones,et al. Factors influencing the spontaneous heating of low-rank coals , 1991 .

[5] J. C. Jones. Self-Heating Tests to Establish the Shipping Safety of Solid Materials: The Case for Briquetted Peat , 1996 .

[6] J. C. Jones. Topics in Environmental and Safety Aspects of Combustion Technology , 1986 .