氧化铝炉窑协同处理二次铝灰的研究

Study of Co-processing of Secondary Aluminum Dross Using Clinker Kiln

针对熟料窑处理二次铝灰的可行性,进行了热力学计算,从理论上研究了二次铝灰中的AlN、 F元素和Cl元素在烧结过程中的行为和存在形态。热力学计算表明,AlN在烧结过程中转化为氮化物和Al_(2)0_(3),F元素在合理的C/S条件下,转化为钠氟石(NaF·2CaO·SiO_(2)), Cl离子可能会缓慢富集,但是有一定的限度。对添加二次铝灰的工艺流程进行了设计,并进行了工业实践;实验结果表明,二次铝灰按照N/R0.92~0.98, C/S1.92~1.98配入石灰和纯碱,添加量在3%时,固氟效果较好,且氧化铝净溶升高,氧化钠净溶变化不大,可实现二次铝灰的综合利用。

In this work,the existing forms and evolution behavior of AlN,F and Cl in secondary alumina ash sintering process were studied by thermodynamic calculation to verify the feasibility of curing secondary alumina dross in clinker kiln.Thermodynamic calculations show that AlN is converted to nitric compounds and Al_(2)O_(3) in the sintering process,and F is converted to sodium fluorspar(NaF·2CaO·Si0_(2))under reasonable C/S conditions.Cl ions may slowly enrich,but with a certain limit.The process flow of adding secondary aluminum dross was optimized and the large-scale industrial practice was carried out.The experimental results show that when lime and soda ash were added in the order of N/R:0.92-0.98,C/S:1.92~1.98,and the addition amount of mixture is 3%,the fluorine retention was efficienct and the net dissolution of dumina increased,and the net dissolution of sodium oxide was stable.Under the optimization conditions,the comprehensive utilization of secondary aluminum dross can be realized.