基于消除微细粒方解石集合体网络结构的白钨矿高效浮选调控方法研究

The fine calcite could easily aggregate in water and form aggregation net-work structures, which has seriously limited the efficiently recovering of finely disseminated skarn type scheelite. The project started by analyzing the aggregation morphology of the fine calcite particles. The formation process and the stabilization mechanism of the fine calcite aggregate net-work structure are studied to reveal its spatial extension characteristic, strength data in the shearing areas in the flotation cell, based on which the influence of the net-works on the pulp rheology including apparent viscosity and yield stress is investigated. The effects of the pulp rheology on the flotation froth properties and the flotation kinetics of the fine scheelite are to be studied. The correlation model “fine calcite aggregate net-work structures’ property-pulp rheology-fine scheelite flotation performance” is to be established. Based on the model, the flotation methods based on high intensity agitation, ultrasonic treatment and adding macromolecular regulator are proposed. The effects of the methods on the pulp rheology are studied, based on which the elimination effects on the fine calcite aggregation net-work structures are quantitatively evaluated. As a result, the high efficient fine scheelite flotation method based on eliminating the fine calcite aggregation net-work structures is formed, exhibiting low froth entrainment rate and high flotation rate. The results could be potentially used in the real ores flotation regarding to depress the fine scheelite and provide theoretical basis and technical support.

微细粒方解石在水中易发生聚集，形成集合体网络结构而干扰浮选过程，是制约微细粒矽卡岩型白钨矿高效浮选回收的重要因素。项目从矿浆中颗粒的聚集形态分析出发，研究微细粒方解石集合体网络结构的形成与稳定化机制，探明网络结构在浮选机不同搅拌区域内的空间伸展、形貌与强度特性，揭示网络结构对表观黏度、屈服应力等矿浆流变性的影响规律；查明矿浆流变性对微细粒白钨矿浮选泡沫性质、浮选动力学的影响机制，建立“微细粒方解石集合体网络结构特性-矿浆流变性-微细粒白钨浮选行为”关联模型；研究强化搅拌、超声波处理、添加大分子调整剂等途径对矿浆流变性的影响规律，阐明微细方解石集合体网络结构的抑制、破坏机制，建立基于消除微细粒方解石集合体网络结构的微细粒白钨矿高效浮选调控方法，为开发利用我国储量巨大的微细粒矽卡岩型白钨矿以及大量损失于尾矿中微细粒白钨矿提供理论依据与技术支撑。

微细粒方解石的高效抑制是矽卡岩型白钨矿浮选中的难题。项目以微细粒白钨矿和方解石为研究对象，采用颗粒集合体形貌观测、矿浆流变学检测、矿物浮选试验和药剂吸附检测相结合的研究体系，研究了微细粒方解石的聚集行为及其对矿浆流变性的影响，开展了矿浆流变性对该体系浮选动力学和浮选泡沫性质的影响研究，在“颗粒聚集行为—矿浆流变性—浮选动力学和泡沫性质—浮选行为”模型指导下进行了调控矿浆流变学提升浮选指标的理论研究和技术原型开发。结果显示，在油酸钠捕收剂体系下，微细粒方解石能够形成比白钨矿更紧密的集合体网络结构，且在同等的抑制剂（海藻酸钠和植酸钠）作用下更难以破裂，而在羟肟酸体系下，微细粒方解石的集合体网络结构能够有效的被抑制剂破坏，表明羟肟酸捕收剂体系能够显著削弱微细粒方解石集合体网络结构行为；葫芦巴胶、海藻酸钠、羧甲基纤维素钠等不同药剂的组合具有流变学协同效应，并能够协同抑制方解石的可浮性，表明高分子药剂之间的流变学协效性与其浮选抑制效果存在关联；微细粒矽卡岩型白钨矿矿浆属于Herschel Buckley流体，通过调控搅拌调浆过程能量输入，能够促进颗粒集合体网络结构的分散，降低屈服应力从而提高浮选分离效率；通过加入粗颗粒搅拌介质，能够调节其矿浆流体类型，促使其向牛顿流体转变，促使矿浆中慢浮组分的浮选速率增加，浮选泡沫的含水率降低、泡沫层厚度减小、泡沫兼并性增强，“二次富集作用”效果得到改善，浮选分离效率得到提升；在此基础上进行了湖南柿竹园钨矿实际矿浮选试验，利用自行设计合成的SI型羟肟酸新型捕收剂，最终获得了精矿品位（以WO3计）30%以上，回收率79%的浮选指标，研究结果为我国储量巨大的矽卡岩型白钨矿的高效开发提供了理论基础与技术借鉴。