Experimental study on selective non-catalytic reduction(SNCR)process and the effect of adding CO on the denitration efficiency were performed on a tubular flow reactor in simulated flue gas atmosphere

at temperature ranging from 650 ℃to 950 ℃.The relative reaction mechanisms were investigated.The results show that

with no CO added

the optimum temperature for SNCR denitration was 900℃.With an increase in reaction temperature

the emission concentrations of both N_2O and NO_2 increased first and then decreased

which were similar to the denitration efficiency curves.At high temperature the ammonia escape reduced.At temperatures below 700℃

increasing the ammonia nitrogen mole ratio had no apparent effect on the denitration efficiency.While at temperatures higher than 800 ℃

with an increase in ammonia nitrogen mole ratio

the denitration efficiency and N_2OO emission concentration both increased

but the NO_2 emissions concentration decreased.With trace CO added

the optimum temperature for denitration and the curve of ammonia escape shifted to a lower temperature and the maximum denitration efficiency increased slightly.The temperature window of N_2O emission was broadened and its peak increased.The NO_2 emission concentration was close to zero.In addition

increasing the CO addition amount can lead to an increase in CO escape at low temperatures.Therefore

in practical application

trace amount of CO can be added to decrease the SNCR denitration temperature and reduce the NO_2 emission concentration and ammonia escape at low temperatures.