颗粒结构对焦粉燃烧性能的影响

在日本铁矿烧结中每年排放约32MtCO2,占总排放量的2.6%。由于烧结废气中含有一定量的CO,因此如果焦粉能够完全燃烧就可减少其消耗量。为明确焦粉在烧结过程中的燃烧机理,目前的研究主要是基于焦粉在铁矿石、石灰石和氧化铝等各种烧结物料颗粒间的位置对其着火温度和燃烧速率的影响。对粗焦粉颗粒来说,铁矿石和石灰石的附着会降低其着火温度,加快燃烧速率。除焦粉和石灰石形成的复合小球状颗粒外,细焦粉颗粒则会黏附于其他物料颗粒表面或者与其他物料颗粒共存形成的复合颗粒,既不会改变焦粉的着火温度,也不会改变其燃烧速率。石灰石对加快焦粉燃烧速率似乎具有催化作用。

Effect of granule structure on the combustion behavior of coke breeze

Iron ore sintering machines in Japan emits 32 Mt CO2 annual,amounting to 2.6 percents of total emission in Japan.Since the exhaust gas contains a few percent of CO,the complete combustion can reduce coke consumption.To obtain the principal for controlling coke combustion in the sintering bed,the present research determined the ignition temperature and the combustion rate of cokes existing in various positions in the granules of sintering raw mixture,which made of coke and one of iron oxide (ore),limestone and alumina.For coarse coke particle,the ore and limestone adhesion lowered the ignition temperature and accelerate the combustion rate.For fine coke particles adhering on various kind of nucleus or coexisting in composite pelletlike granule,neither the ignition temperature nor the combustion rate changed except for a composite pelletlike granule of coke and limestone.The acceleration effect of limestone on coke combustion rate seems to derive from catalysis effect.