Ignition characteristics of coal powder airflow was investigated with a one dimensional furnace under various oxygen-enriched conditions

to get their changing laws.The results show that with oxygen concentration increases

ignition temperature of four kinds of coals decrease greatly and do faster for low volatile coals

and an obvious transformation is observed for ignition mode of pulverized coals

from homogeneous to heterogeneous

the oxygen concentrations corresponding to the transformation are about 40% for bitumite

50%—60% for lignite and about 30% for both lean coal and anthracite

respectively. With oxygen concentration increasing

the optimal coal powder concentrations increase first and then decrease for bituminous coal and lignite

but decrease slowly for lean coal and anthracite.