Mechanism And Applications Of Milling-floating Technology On Selective Regirnding Of Flotation Middlings

Mankind is faced with problems of environment and resources, and ecological damage in the 21st century. The shortage of resources has become main bottlenecks of sustainable development. Under the background of available nonferrous metal mineral resources apt to poor?tiny and complex, beneficiation process became more and more difficult, as economic development and demand of high quality mineral resources, It is highly important to increase recovery of mineral resources.To solve current realistic issues such as declining recovery in resources, lower grinding efficiency, unreasonable grain sizes of milling discharged particles, the paper proposed technology concepts based on selective regrinding of flotation middling(SRFM) including flotation maximum diameter (Dfmax), coarser milling, fine classification, etc.. Dfmax and fine classification could improve separation efficiency, reduce energy consumption of unit ore; decrease amount of more shattered particles. It could be beneficial to following flotation because the new process markedly decrease amount of coarse particles, optimize grain size, settle the problem of coarse particles without crushing and fine coarsely milled particles by adopting above new technology.Exploring the ball ratio, ground pulp density, grinding time, etc., it was found that intermediate size minerals were shut down by flotation maximum diameter(Dfmax), coarser milling, fine classification technology than in the corresponding open-circuit grinding process. Continuous grinding test shown that milling size -0.074mm was reduced from 65% to 60% in original flowsheet by using new technology; Milling production capacity from 113 to 142 kilograms per hour, production capacity is relatively higher 25.67%; in 2# milling process, the separation efficiency was relatively higher 104.48% in 1# milling process, and the returning sand ratio was relatively less than 15.36%, than 3% about 25mm; the amount of particles reduced 93.75% for greater than 0.25mm size, increased 7.61% for between 0.25 and 0.019mm size, reduced 8.29% for less than 0.019mm size. New milling technology could improved feeding granularity overall.It was researched that separation efficiency influenced on returning sand ratio in closed-circuit, moreover formulated number assigned formula between coarse and fine particles, continuous grinding test shown the results were correct and accuracy, with the experiment contrast and draw up number assigned figure when Dfmax was 0.30mm. Introduced Kelsall model, and further deduced flotation model for copper ore, the paper compared?=?(1-e-Kt) with W=W0(1-P)N, and found flotation power was affinities between kinetic model and probabilistic model. Two mathematical functions were fitted to flotation time and recovery in the flotation kinetic model research, it was found that hyperbolic function was better than exponential function, the N—level flotation kinetic model formula as:For QINGHAI copper, flotation conditions was pH equal 10, and sodium butyl xanthates concentration 50g/t, abies oil 31g/t. When N equal 2, the correlation coefficient R2=0.9988, and K=0.0206.The paper made use of technology including flotation maximum diameter(Dfmax), coarser milling, fine classification, based on SRFM to investigate and analyze HUBEI copper mine, ANHUI copper mine. It were shown that as following, (1) in HUBEI copper mine experiment, the recovery of copper in new technology and original reagent parameter process was higher 2.43% than in old technology and original reagent parameter process, moreover the recovery in new technology and new reagent parameter process was higher 4.99% than in old technology and original reagent parameter process. (2) in ANHUI copper mine experiment, the grade of copper in closed-circuit milling with original reagent parameter process was 21.59%, recovery was 90.73%, the recovery was higher 1.44% than in old technology with open-circuit milling. The grade 22.86% and recovery 92.73% were achieved in Partly prior flotation with original reagent parameter process, the recovery was higher 3.44% than in old technology. The grade 22.80% and recovery 94.89% were achieved in Partly prior flotation with new reagent parameter process, the recovery was higher 5.60% than in old technology.