To investigate the influence of combustion atmosphere

ambient temperature

O_2 concentration and gas flow on the NO releasing and the coal combustion characteristics

the combustion experiments were carried out on a horizontal tube furnace.The results show that

compared with the O_2/N2 atmosphere and O_2/Ar atmosphere

the discharge amount of NO and the peak temperature decreased

and the reaction time became longer in O_2/CO_2 atmosphere.As the temperature rose from 1 200 Kto 1 300 K

the reaction time shortened

while the NO emission increased and peaked at 1 300 K.When the temperature increased further

the NO reduction rate was greater than the generation rate and the NO emission decreased.When the O_2 concentration was below 10%

the oxidizing reaction of N was inhibited and the corresponding NO emission was low.On the contrary

the CO/NO/char reduction reaction was inhibited and the corresponding NO emission grew rapidly when the O_2 concentration ranged from 10% to 21%.With an increase in the gas flow

the O_2 concentration around the pulverized coal particle increased

which enhanced the oxidizing reaction rate of N

so the corresponding conversion rates of N became greater.