高镁磷尾矿酸解反应行为研究

Research on Acidulation Behavior of Phosphate Tailings with High Magnesium Content

对磷矿浮选尾矿在硫酸中的酸解行为进行了研究。考察了搅拌强度和粒度对酸解过程的影响,重点探讨了P2O5、MgO、Fe2O3、Al2O3的酸解行为,并研究了尾矿连续酸解反应行为。研究结果表明:搅拌速度提高到300rpm以上时,磷尾矿酸解反应受扩散控制;粒度对尾矿分解率的影响不明显;尾矿中MgO和P2O5均以较高溶解率溶解进入溶液(大于75%),且二者浸出率相差不大、随各因素变化的趋势大致相同,只是前者略高于后者;Fe2O3、Al2O3的溶解行为受硫酸浓度的影响较大,铝杂质的溶解率较铁杂质高;溶液中的镁富集到一定程度时会以结晶态析出。

Acidolysis behaviors of the phosphorite tailings in sulphuric acid are researched. The influence on a- mount of agitation and size is tested and acidolysis behavior of P2O5, MgO, Fe2O3 and Al2O3 are explored specially. The results show that the reactions are controlled by diffusion when amount of agitation is up to 300 rpm. Effect of size on decomposition rate of tailings is not clear. MgO and P2O5 dissolve into solution at high leaching rate （more than 75% ） with relatively similar leaching rate and changing trends to all kinds of factors. Only the former is a bit higher than the latter. Effect of H2 SO4 concentration on solution behavior of Fe2O3 and Al2O3 is large when leaching rate of Al2O3 is higher than Fe2O3. MgO enriched to some extent can crystallize.