利用聚合氯化铝降低隐石墨浮选过程中绢云母脉石的夹带

Reducing entrainment of sericite gangue in microcrystalline graphite flotation by polyaluminum chloride

利用聚合氯化铝(PACl)凝聚绢云母降低其泡沫夹带。研究结果表明:绢云母的粒径不仅影响精矿的水回收率,而且严重地影响绢云母的夹带回收率。在自然p H条件下,PACl水解产生的快速反应聚合物Alb、不反应的胶体物质Alc分别通过电中和机制及絮凝机制有效地选择性凝聚绢云母。PACl质量浓度为200 mg/L时,隐石墨浮选精矿的水回收率及灰分分别从空白实验的34%和24.5%降低到23%和16.8%。PACl能选择性地凝聚绢云母,有效降低绢云母的泡沫夹带,改善隐石墨浮选选择性。

Polyaluminum chloride （PAC1） was tried to reduce entrainment of sericite. The results show that with the decrease of sericite particle size, both the water recovery and entrainment recovery of sericite sharply increase. At natural pH, the hydrolysis products of PACl are fast-reacting polymeric （Alb） and slow-reacting colloidal species （Alc） which play vital roles in selective coagulation of sericite. Actions of Alb and Alc are generally explained in terms of two distinct mechanisms, i.e. charge neutralisation and sweep flocculation. In the absence of PAC1, the water recovery and ash content of microcrystalline graphite froth concentrate are 34% and 24.5%; when the mass concentration of PACl is 200 mg/L, they decrease to 23% and 16.8%, respectively. PAC1 can reduce entrainment of sericite gangue effectively by selective coagulation and improve the flotation selectivity of microcrystalline graphite.