Research On System Optimization In The Process Of Separation And Enrichment Of Mineral Materials

Separation and enrichment are the processing techniques of mineral materials. There are however few studies on the topic. Ilmenite is an important mineral material. And ilmenite reserve of China is ranked first in the world. At present, a large quantity of erosion and complex technique are major problems in separation and enrichment of ilmenite. All size fractions flotation for recovering ilmenite from tailings of iron in Panzhihua area, Sichuan province, is taken as an example in the paper to explore optimal design and reduction of dimensions of the parameters in separation and enrichment. The dimensions of the parameters are reduced and optimization is satisfactorily achieved.The collector of ilmenite is selected rationally from the characters or parameters of modified surface. The surface parameters are obtained from the measurements of wetting angle on bulk materials or minerals. An innovative method based on Hough Transformation is put forward for the measurement of contact angle. The contact points are detected automately with more accuracy and higher robustness, when this method is applied. The behavior that the bubbles are formed from gas evolution on the bulk materials in a vaccum is studied in our work. It is found out that the behavior is strongly correlated with the proton acceptor component, which is one of the surface energy parameters. Specifically, the less proton acceptor component, the more bubbles formed on the bulk material."Aerophilic", which is defined to measure the behavior aboved, is referred to selection of ilmenite collector that is SYB1#. The flotation tests show that the collector is superior to two constrastive collectors.Single size feed is produced by grinding optimization. The correlation between the quality of concentrate and the distribution of particle size is analysed. Meanwhile, the analysis is used to grinding optimization. An amount of fine particle is produced in case of feeding to mill without any pre-processing. Indeed, the excessive fine particle is fatal to flotation. The optimized grinding with pre-screening produces less fine particle. The correlation analysis indicates that the particles in size-0.074? +0.045mm are beneficial to ilmenite flotation. The optimized grinding time is3-4min.The mixture experiment design is applied to select the depressor. The depressor mixture experiment at pH=5,7,9shows that carboxymethyl cellulose sodium (CMC) is the efficient depressor to flotation. In addition, high grade concentrate is recoved when CMC is used. And the recovery increases with the reduction of pH value. The satisfying rough concentrate is obtained by Response Surface Methodology (RSM). The grade and recovery of rough concentrate is40%and60%respectively in the condition that collector dosage, depressor dosage and pH is1025g/t,1025g/t, and5respectively. In addition, the grade of rough concentrate is significantly influenced by two interactions:collector dosage and depressor dosage, depressor dosage and pH value. In concentration flotation, the positive synergistic effect between collector dosage and pH value is beneficial to the recovery of ilmenite concentrate.The general desirability function is defined to convert multi-objective into single objective. The quality of concentrate is raised by optimization of multi-objective. The recovery of concentrate reaches up to40%as the grade reaches up to47%. The simulation of parameters fluctuation indicates that concentration flotation works with high robustness. The fluctuation of parameters causes only a slight decrement of the recovery. In contrast, the grade of concentrate is immune to fluctuation. Besides, a phenomenon called "complemental effect" is found in simulation. In detail, the recovery variation resulted from the fluctuation of three parameters (collector dosage, depressor dosage and pH value) is less than the variation resulted from the fluctuation of pH value. The recovery of concentrate is increased to45%by the optimization of SYB1#. And the restriction on pH value is relaxed obviously.