拜耳法助滤剂研制

拜耳法氧化铝生产中。溶出矿浆经重力分离沉降槽液固分离后。溢流溶液中仍然合有一定的浮游物杂质．在分解之前。需要对溢流进行二次净化，以脱除其中的浮游物。国内拜耳法氧化铝厂目前采用的二次净化方法一般是用凯利叶滤机过滤。受溢流溶液的物理化学性质的影响，叶滤机产能常常会受到溢流溶液过滤速率的限制。铝酸三钙既能加快拜耳法溶液的过滤速率，又能降低滤液的浮游物含量。本文论述了合成铝酸三钙的技术条件对其助滤性能的影响。研究表明，合成温度、钙铝摩尔比、碱浓度会影响助滤剂铝酸三钙的粒度分布、晶体结构及组成，继而影响其助滤性能。控制适宜的合成条件。可以制备出助滤性能优良的铝酸三钙。

The manufacture of tricalcium aluminate

In the Bayer Process, production of alumina is limited by the rate of liquor passing through Kelly Presses. Kelly Presses are utilized for secondary clarification, Tricalcium Aluminate are used to trap solids after the initial clarification in gravity settlers, Desirable qualities of Tricalcium Aluminate permit fast liquor flow rate and filter solids to low concentrations. This paper offers some explanations on how physical and chemical conditions in triealcium aluminate production govern desirable properties, Slaking temperature, lime to alumina ratio, and soda concentration affect triealeium aluminate partical size distribution, crystal structure, and composition, and these properties are thought to affect the flow of liquor through Kelly Presses, By controlling slaking conditions . suitable filter aid can be made.