A comparative kinetic study of SNCR process using ammonia

M. Tayyeb Javed, Z. Ahmed, M. Asim Ibrahim, N. Irfan
2008 Brazilian Journal of Chemical Engineering  
The paper presents comparative kinetic modelling of nitrogen oxides (NO x ) removal from flue gases by selective non-catalytic reduction process using ammonia as reducing agent. The computer code SENKIN is used in this study with the three published chemical kinetic mechanisms; Zanoelo, Kilpinen and Skreiberg. Kinetic modeling was performed for an isothermal plug flow reactor at atmospheric pressure so as to compare it with the experimental results. A 500 ppm NO x background in the flue gas is
more » ... onsidered and kept constant throughout the investigation. The ammonia performance was modeled in the range of 750 to 1250 o C using the molar ratios NH 3 /NO x from 0.25 to 3.0 and residence times up to 1.5 seconds. The modeling using all the mechanisms exhibits and confirms a temperature window of NO x reduction with ammonia. It was observed that 80% of NO x reduction efficiency could be achieved if the flue gas is given 300 msec to react with ammonia, while it is passing through a section within a temperature range of 910 to 1060 o C (Kilpinen mechanism) or within a temperature range of 925 to 1030 o C (Zanoelo mechanism) or within a temperature range of 890 to 1090 o C (Skreiberg mechanism).
doi:10.1590/s0104-66322008000100012 fatcat:q23nbq3np5d2le2xbkpviuam5q