Experimental Research Of Mineral Processing On Xinjiang Refractory Andalusite

Andalusite,whose chemical formula is Al₂O₃,is a kind of high aluminum mineral that belongs to aluminosilicate minerals.It is also an important raw material to manufacture advanced refractory materials.With the development of Chinese industry,more and more high aluminum materials are demanded,which led to the more and more extensive application of andalusite.The Xinjiang Gelanti andalusite ore could not be applied in the industrial manufacture directly because of its low andalusite content.So,beneficiation is necessary before the application of Gelanti andalusite ore in the industrial manufacture.However,several disadvantages,such as the low grade aluminium oxide in the raw ore,serious air-slake phenomenon,high contents and various kinds of gangue mineral,the complex commensalism and inbuilt state of andalusite and gangue mineral,have made the beneficiation of Xinjiang Gelanti andalusite ore more difficult.The paper has conducted systematic mineral processing experiments based on the mineralogical researches of this type of andalusite ore,and the main contents and results of the test have been shown as followed:?1?According to the X-ray diffraction?XRD?phase analysis,X-ray fluorescence?XRF?analysis and microscopic analysis,the main chemical composition contents of raw Xinjiang Gelanti andalusite ore were confirmed.The content of SiO₂,Al₂O₃,TFe₂O₃,Na₂O,K₂O and CaO were 66.17%,18.48%,4.25%,2.09%,1.78%and 1.03%,respectively,and the loss on ignition was 3.53%.Meanwhile,the major mineral compositions in the raw ore were also confirmed.The content of andalusite,quartz,black mica?or white mica?,albite,chlorite,magnetite,carbon content and garnet were 10%,35%,25%,15%,3%,2%,3%and 3%,respectively.The content of objective mineral,andalusite,was relatively low.However,the gangue mineral had high contents and complex varieties.Moreover,the dissemination size of andalusite in the raw ore was relatively thick.So,the separation of andalusite monomer was relatively easy.However,the existence of thinner black mica,quartz,iron contents and carbon contents in the andalusite made the separation of andalusite monomer more difficult.?2?According to the experiments,it could be concluded that the ore grinding was steel ball.The grinding fineness of coarse grinding was-0.074mm,and the content was 78.36%.A relatively better open flowsheet,which was desliming,then once magnetic separation,and then once decarburization,and then once rougher flotation,and the last four times exact flotation,was adopted.And the productivity of andalusite concentrate,the alumina content and the alumina recovery of the concentrate were 3.54%,55.92%and 9.97%,respectively.?3?According to the experiments,the optimum mineral processing flow was confirmed,which was ore grinding with ball-milling,then desliming,and then once magnetic separation,and then once decarburization,and then once rougher flotation,and four times cleaning,and the tailings of step 5,6,and 7 were merged.And then,the merged tailings were regrinded and then conducted redesliming and recleaning.The grinding fineness was-0.074mm,and the content was 78.36%.The regrind concentration was 22.11%.And when the regrinding fineness were respectively+0.074mm,-0.074+0.045mm and-0.045mm,the regrinding contents were 16.56%,39.3%and 44.11%,respectively.Meanwhile,the desliming granularity was 30?m,and the intensity of magnetic separation and flow velocity of pulp were 1.0T and1.1cm/s,respectively.The decarburization collector was kerosene and its dosage was55g/t.The foaming agent was pine camphor oil and its dosage was 23g/t.The collector of floatation of andalusite was petroleum sodium sulfonate,and the inhibitor was sodium fluosilicate.The pH of the pulp was 3.0³.5.With this process,the productivity of andalusite concentrate 1,the alumina content and the alumina recovery of the concentrate were 3.60%,55.78%and 10.80%,respectively.And the productivity of andalusite concentrate 2,the alumina content and the alumina recovery of the concentrate were 1.73%,54.37%and 5.06%,respectively.After the combination of andalusite concentrate 1 and 2,the productivity of andalusite concentrate,the alumina content and the alumina recovery of the concentrate were5.33%,55.32%and 15.86%,respectively.?4?The mechanism researches has indicated that the adsorption mode of petroleum sodium sulfonate on the surface of andalusite were chemisorption and physical absorption,and the adsorbing capacity of petroleum sodium sulfonate on the surface of andalusite much larger than that of quartz.