time is the same as that corresponding to pore diffusion control (Equation ( )). If the evolution of surface area can be described by: S/S,=(l-f)"3 (6) the resulting equation for the conversion coincides with that for film-diffusion control (Equation ( )). Therefore, it is concluded that much care
The effect of agitation on the char combustion characteristics of large coal particles
โ Scribed by A.A. Malik; D. Pehlivan; C.R. Howarth
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 412 KB
- Volume
- 75
- Category
- Article
- ISSN
- 0016-2361
No coin nor oath required. For personal study only.
โฆ Synopsis
To simulate combustion behaviour in a pilot-scale combustor, a laboratory-scale agitated combustor has been developed which allows burnout and combustion rates for large coal particles to be measured. Particle sizes up to 25 mm can be studied, typical of those used in fixed-bed retorts. Char burnout data were obtained to supplement previously published volatiles release data. A power law relationship between char burnout time, tb, and particle size, d~, given by t b = kdd p is proposed, with k d and n as correlation constants., The data were also used to correlate char combustion rates, re, for single particles, in the form ro = kr/d p .
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