On a self-designed fixed bed reactor the factors influencing the formation of reducing volatiles from the coals for reburning are investigated with a Gasmet fourier transform infrared spectroscopy analyzer. The experimental results show that reducing volatiles

such as CO

CH

4

and HCN

can be found during the heating process of Shenmu coal in N

2

and CO

2

atmosphere

CO

2

atmosphere gets better for the generation of CO. The generation of CH

4

in N

2

is similar to that in CO

2

. The presence of O

2

in the atmosphere exerts on obvious influence on the formation of CO

CH

4

and HCN

as well as the emission of NO. O

2

decreases the initial formation temperature of CO and CH

4

and their productive rates

while it increases the productive rate of NO. The initial formation temperature of HCN is greatly decreased in the presence of O

2

while the productive rate of HCN is increased remarkably in O

2

of 6%. The heating rate affects the formation of reducing volatiles. No matter in N

2

or in CO

2

the yield of CH

4

during rapid heating process is greater than that during temperature-programmed heating process

while the yield of CO is reversed. The effect of heating rate on HCN generation depends on coal types. Except TC coal

the yield of HCN during rapid heating process in N

2

or in CO

2

is lower than that during temperature-programmed heating process.