钠硅渣中氧化铝回收工艺的研究进展

Progresses of Recovery of Alumina from Sodium Aluminosilicate Hydrate

钠硅渣,即水合铝硅酸钠(Na2O·Al2O3·1.7SiO2·2H2O)是碱法处理铝土矿时最重要的反应产物,产量大,且其中含有大量的氧化钠和氧化铝,因此必须加以回收利用。文章介绍了国内外钠硅渣中氧化铝的回收方法和研究进展,其中包括火法、湿法和生物法。同时对这些方法的工艺原理和特点进行了分析,并指出高压水化学法和钠硅渣湿法处理新技术应用前景较好,应加强其基础理论研究。

Sodium-silicon residue,namely sodium aluminosilicate hydrate is the major reaction residue when processing the bauxite by the alkali treatment.The large amount output of sodium aluminosilicate hydrate which contains considerable alumina and sodium oxide calls for an necessary action to be recovered.Processes and latest progresses in the recovery of alumina from sodium aluminosilicate hydrate are summarized,such as fire method、wet method and biological method.Meanwhile,their principles and characteristics are analyzed,and it is pointed that high pressure hydro-chemistry method and a new hydro-treatment technology of sodium aluminosilcate hydrate are very promising,and the basic theory research still need to be strengthened.