- Title
- Mechanistic Investigations of Particle Ignition of Pulverized Coals: An Enhanced Numerical Model and Experimental Observations
- Creator
- Li, Lili; Tahmasebi, Arash; Dou, Jinxiao; Rish, Salman Khoshk; Tian, Lu; Yu, Jianglong
- Relation
- Energy & Fuels Vol. 34, Issue 12, p. 16666-16678
- Publisher Link
- http://dx.doi.org/10.1021/acs.energyfuels.0c03093
- Publisher
- American Chemical Society
- Resource Type
- journal article
- Date
- 2020
- Description
- The ignition behavior of coal particles was studied through an enhanced numerical model, combined with experimental investigations in a visual drop tube furnace in the temperature range of 1100–1300 K. The devolatilization and the combustion of volatile and char during combustion of single coal particle were thoroughly studied. The devolatilization model was established with the results calculated from the chemical percolation devolatilization (CPD) model. The modeling results were used to clarify the relationship between particle temperature and volatile yield, which simplified the calculation of devolatilization kinetic parameters and improved the accuracy of predicted results. The CPD model predicted the heating values and the total yield of volatiles at different heating rates. The energy generated by the combustion of volatile was postulated to heat a radiating cloud around residual char particles. Hence, the residual char particles were indirectly heated by the radiating cloud, leading to an enhanced volatile release rate. The enhanced model was also used to explain the effects of particle size, temperature, and coal type on the ignition mode of particles and predict the transition from heterogeneous to homogeneous ignition. The results suggested that the ignition mechanism depended not only on the heating rate and pyrolysis rate of the coal particles but also on the mass of volatile released per unit surface area, the rate of volatile release, and the volatile’s composition. The study also explained why lignite with a high volatile content undergoes less homogeneous ignition than high-volatile bituminous coal.
- Subject
- bituminous coal; coal research; heating rate; ignition; numerical models; particle size
- Identifier
- http://hdl.handle.net/1959.13/1438855
- Identifier
- uon:40746
- Identifier
- ISSN:0887-0624
- Language
- eng
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