A general method for determining chemical kinetic parameters during ignition of coal char particles

✍ Scribed by Wei Biao Fu; Tao Fang Zeng

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 689 KB
• Volume: 88
• Category: Article
• ISSN: 0010-2180
• DOI: 10.1016/0010-2180(92)90043-o

✦ Synopsis

A new viewpoint is presented that the activation energy, E, is independent of coal type and only varies with the temperature of particle, but the frequency factor of coal char, ko. oh, varies with coal type. We have determined that E = 152 kJ/mol (36.3 kcal/mol), which is a constant in oxidation of any kind of coal char in air during ignition. The relationship between ko, ch and coal type, which is also applicable to any kind of coal, is presented. These are different from the previous references in which E and ko. ch all vary with coal type, but no general rules have been found. A new dimensionless number, Fz, which is used to indicate the ignition characteristics of coal char, is also presented. Fz depends only on the proximate analysis of coal and reflects the ignition property in a combined way, so that Fz is called the ignition index of coal, It is a very useful parameter for engineers and operators to use in predicting the ignition characteristics of different types of coals.

NOMENCLATURE

Yo2, A ash (%); constant Bi Bi number c carbon content (wt. %)