摘要
阐述了流化床条件下Ｎ２Ｏ形成和分解机理，采用不同程度脱去挥发份的焦炭颗粒，研究脱挥发份的程度对Ｎ２Ｏ形成的影响，脱挥发份的温度越高，即脱挥发份的程度越高，焦炭形成Ｎ２Ｏ的量越少，这表明挥发份氮形成Ｎ２Ｏ量高于相应焦炭氮燃烧产生的Ｎ２Ｏ量。燃料燃烧过程中，ＮＯ形成比较均匀，而Ｎ２Ｏ比较复杂，燃料氮转变为ＮＯ的转化率随脱挥发份温度升高而增加，而Ｎ２Ｏ的转化率则有一临界脱挥发份温度点。燃料氮转变为Ｎ２Ｏ的转化率随燃烧温度升高而降低，ＮＯ则相反。氧化钙对Ｎ２Ｏ有较强的分解作用，固体物料对Ｎ２Ｏ的分解作用比对ＮＯ的快。Ｎ２Ｏ和ＮＯ的分解反应过程可用一级Ａｒｒｈｅｎｉｕｓ公式来描述。
Nitrous oxide formation and reduction mechanisms are studied in a bench scale FBC.In order to investigate the effect of the partial devolatilization,the char,prepared at various devolatilization temperature,is burnt.N 2O emission dependents strongly on the devolatilization temperature.It shows that the higher temperature at which char devolatilized,the lower N 2O formated.With increase in burning temperature,the with increase in burning temperature.The fuel N conversion ratio to N 2O is increasing,while the ratio to NO is decreasing.The results show that there exists a optimum range of devolatilizing temperature that gives a maximum conversion to N 2O,and nitrogenous species in the char during burning are highly converted to N 2O.The contribution of volatile to N 2O is larger than that of char.Reduction activities of solid particles on N 2O and NO are measured.CaO shows higher N 2O reduction activity.N 2O reduction rate is always faster than that of NO for the same particles.Both N 2O and NO reduction rate can be expressed as one order Arrhenius form.
出处
《中国电机工程学报》
EI
CSCD
北大核心
1999年第1期47-51,共5页
Proceedings of the CSEE
