The ammonia is commonly used as reductant in SCR denitrification system

which can be prepared from materials

such as liquid ammonia

ammonia water

ammonium bicarbonate

and urea etc..The calculation method of consumption for using above-mentioned materials respectively as reductant in SCR denitrification and their safety in utilization have been presented.When using liquid ammonia and ammonia water as reductant

the cost in storage

transportation

and preparation is lower

but certain danger exsists;the safety of urea is better

but the cost is higher;and its decomposition is difficult;the ammonium bicarbonate can be prepared by using two methods

i.e.pyrolysis and hydrolysis

and its prise is also cheaper than urea.