铝灰脱氮的实验研究

Experimental research on denitrification of aluminum dross

研究了一种新的铝灰脱氮工艺。讨论了焙烧温度,药剂添加比和保温时间对铝灰脱氮率的影响。采用XRD,SEM,EDS,XRF和氮元素分析仪分析了焙烧前后的铝灰。铝灰与药剂的混合焙烧可以有效地脱除铝灰中的氮化铝。保持焙烧温度为890~920℃,药剂添加比为32.5~35 wt.%,保温时间为2.5~3 h,可以达到较好的脱氮效果,最大脱氮率达到98.13%。考虑到能耗和成本问题,推荐的焙烧条件为890℃,35%和2.5 h。AlN最终分解为Al_(2)O_(3)和N_(2),药剂与铝灰中的Al_(2)O_(3)和SiO_(2)反应形成多孔结构的Na_(1.95)(Al_(1.95)Si_(0.05)O_(4)),称为沸石。脱氮过程无废水废渣、环境友好。

A novel denitrification process of aluminum dross was studied. Influences of baking temperature, reagent addition ratio and holding time on the denitrification ratio of aluminum dross were discussed. XRD, SEM, EDS, XRF and nitrogen element analyzer were used to analyze aluminum dross before and after baking. Aluminum nitride in aluminum dross can be removed effectively by baking the mixture of aluminum dross with a reagent. Satisfactory denitrification result can be achieved, with the maximum denitrification ratio reaching 98.13%, by keeping baking temperature at 890~920 ℃, regent addition ratio at 32.5~35 wt.% and holding time at 2.5~3 h. Taking into account energy consumption and cost issues, the recommended baking parameters are 890 ℃, 35% and 2.5 h. Finally AlN is decomposed into Al_(2)O_(3) and N_(2). The reagent reacts with Al_(2)O_(3) and SiO_(2) in aluminum dross to form Na_(1.95)(Al_(1.95)Si_(0.05)O_(4)) with a porous structure, called zeolite. The denitrification process is environmentally friendly without waste water and solid waste.