布朗气对煤粉低氧燃烧催化影响

Catalytic Effect of Brown Gas on Low Oxygen Combustion of Pulverized Coal

低氧燃烧技术是降低NOx排放的方法之一,但该技术降低了氧气浓度,导致燃烧不充分,造成了水冷壁被腐蚀等故障。为解决此类问题,通过管式炉实验平台,在低氧浓度环境下掺入不同配比的布朗气,观察烟气中各气体的浓度、反应后的煤粉失重率及固体残渣中固定碳占比。结果表明:当掺入1%布朗气后,煤粉的失重率增加了9.82%,残渣固定碳的含量减少了47.06%;当掺入2%布朗气后,煤粉的失重率增加了10.36%,残渣固定碳的含量减少了49.16%,且在反应前期还原性气体CO和CH_(4)的析出值达到峰值的时间分别提前了4 min和3 min,在反应前期营造了还原性燃烧气氛。由此可见,通入布朗气有利于煤粉低氧燃烧技术的实际应用。

Low oxygen combustion technology is one of the means to reduce NOx emission.However,due to the reduction of oxygen content,the technology leads to insufficient combustion and water wall corrosion.In this paper,through the tubular furnace experimental platform,brown gas with different proportions was mixed in the low oxygen concentration environment to observe the gas concentration of the flue gas,the weight loss rate of pulverized coal after reaction and the fixed carbon content in the solid residue.The experimental results show that when 1%Brown gas is added,the weight loss rate of pulverized coal increases by 9.82%and the fixed carbon content of residue decreases by 47.06%.When 2%Brown gas is added,the weight loss rate of pulverized coal increases by 10.36%and the fixed carbon content of residue decreases by 49.16%.In the early stage of the reaction,the time when the precipitation value of the reducing gases CO and CH_(4) reached its peak value is 4 minutes and 3 minutesearlierrespectively,creating a reducing combustion atmosphere in the early stage of the reaction.It can be concluded that the introduction of brown gas is beneficial to the low oxygen combustion of pulverized coal.