添加剂对一水硬铝石矿增溶溶出过程的影响

Effect of Additives on the Digestibility of Diasporic Bauxite in the Sweetening Process

分别以烧结法粗液直接进行深度碳分所得到粗氢氧化铝和工业上常用的三水铝石矿作为添加剂，进行了一水硬铝石矿增溶溶出过程的对比研究，主要考察了增溶温度、添加剂添加量和增溶时间等因素对溶出效果的影响，同时对增溶溶出矿浆与常规拜耳法溶出矿浆的沉降性能进行了对比研究。研究结果表明，两种添加剂的增溶溶出效果差别不大，因此采用粗氢氧化铝作为增容溶出过程的添加剂在工艺上是可行的，其遁宜的增溶溶出工艺条件为增溶温度210-220℃，赠溶时间15～20min，添加量为前期拜耳法加入量的12％～15％。增溶溶出得到的矿浆，具有优良的沉降和压缩性能。

To study the sweetening process of diasporie bauxite, Al（OH） 3 obtained from the direct carbonization of unrefined sintering solution was used as the additive and its performance was compared with that of the conventionally used gibbsite. The effects of sweetening temperature, Al（OH）3 dosage and sweetening time on the digesting efficiency were investigated, while the settling effects of the digesting slurry from the sweetening process and from the conventional Bayer process were also comparatively studied. No significant difference between the digesting efficiencies using Al （OH） 3 or gibbsite was observed, which indicates that it is feasible to use coarse grain Al（ OH ）3 as a substitutional additive in sweetening process. To obtain optimal digesting efficiency, the sweetening temperature should be controlled in the range of 210 - 220 ℃, and the sweetening time of 15 -20 min, while the supplementally fed Al（OH） 3 should be 12%-15% of the dosage added during the preceding Bayer process. The slurry from the sweetening process shows better effect and compressive properties than that from Bayer process.