非金属矿物加工与利用-单质非金属矿

非金属矿物加工与利用•概述•非金属矿物选矿与提纯技术•非金属矿物超细粉碎与分级•粉体表面改性•其它技术非金属矿物选矿与提纯技术•硅酸盐矿物•碳酸盐矿物•硫酸盐矿物•单质非金属矿•其它非金属矿1碳质非金属矿-石墨及金刚石1.1石墨的选矿及提纯技术化学成分密度莫氏硬度形状晶系颜色光泽条痕C2.1-2.31-2板状及鳞片状六方铁黑钢灰金属光泽光亮黑色主要性质•耐高温性。熔点3850°C，沸点4250°C。强度随温度升高而加强。•导电及导热性能。导电性能比一般非金属矿高100倍，导热性超过钢、铁、铅等金属材料，热导率随温度升高而降低。•润滑性。石墨鳞片越大，摩擦系数越小。•化学稳定性。常温下具良好的化学稳定性。•可塑性。韧性很好，可碾成很薄的薄片。•抗热震性。高温下可经受温度的剧变而不破碎，温度突变时体积变化不大，不会产生裂纹。•鳞片石墨结晶较好，晶体粒径大于1微米，最大可达10毫米，多呈集合体，矿石品位较低（3%-13.5%）。伴生矿物有云母、长石、石英、透闪石、透辉石、石榴子石和少量硫铁矿、方解石等，有时伴生有金红石、钒云母等。•微晶石墨呈微晶集合体，晶粒小于1微米，矿石呈灰黑色、钢灰色，一般光泽较暗淡，具有致密块状、土状及层状、叶片状。伴生有红柱石、水云母、绢云母及少量黄铁矿、电气石、褐铁矿、方解石等。微晶石墨品位较高，一般为605-90%，但矿石可选性差。而且其工艺性能不如鳞片石墨，工业应用范围较小。石墨矿分鳞片石墨和微晶石墨两大类，其中微晶石墨也称为土状石墨和无定形石墨。主要用途•耐火材料石墨坩锅、冶炼炉内衬•导电材料石墨电极、显像管•耐磨材料及润滑剂石墨盘根、润滑脂•密封材料泵的活塞垫圈•隔热材料火箭喷嘴•耐腐蚀材料酸洗槽加工技术•选矿提纯目前技术下纯度可以达到95%•化学提纯利用强酸碱处理，溶解其中的杂质•高温煅烧提纯高温下蒸发灰分杂质，石墨再结晶黑龙江柳毛石墨矿选矿工艺•原矿品位13%-18%•主要伴生矿物斜长石、石英、透闪石、石榴子石、白云母、正长石、绿泥石、褐铁矿、斑铜矿、黄铁矿等•精矿品位90%-93%，回收率70%以上再磨介质选择？氢氧化钠高温熔融法500度以上时通过与氢氧化钠反应生成溶于水的化合物（如硅酸钠），另一部分如铁的氧化物碱熔后用盐酸中和，生成溶于水的氯化盐。石墨精矿可以达到98%高温煅烧提纯•在纯化炉中进行•2500度以上隔绝空气保温72h以上。•炉内通入氯气和氟，最后通入氮气，强化杂质的挥发，可使纯度达到99.99%石墨的其他加工技术•粉碎加工技术包括干法加工工艺和湿法加工工艺等•石墨层间化合物1.2金刚石的选矿及提纯技术类别性质矿物成分化学组成碳在高温高压下的结晶体Si、Mg、Al、Ca、Ti、Fe等总含量约0.001%-4.8%矿物晶体晶体构造等轴晶系常见晶形以八面体和菱形十二而及其聚形为主力学性质硬度莫氏硬度10脆性较脆密度一般3.47-3.56，结晶完好3.52解理平行八面体或平行十二面体断口贝壳状光学性质颜色无色透明，但较少见，多数呈不同颜色光泽金刚光泽，少数呈金属光泽折射率2.40-2.48透明度纯净者透明,一般为透明、半透明、不透明异常干涉色正交偏光镜下的干涉色应为黑色，但很多呈异常干涉色发光性阴极射线下发绿、蓝色荧光，X射线下发中等或微弱的天蓝色荧光磁电性质磁性非磁性介电常数15度时为16-16.5电导率电的不良导体摩擦电性与玻璃、硬橡胶、有机玻璃表面摩擦产生电荷热学性质热导率液氮温度下为铜的25倍,但随温度升高而降低比热容随温度升高而增大热膨胀性低温时很小,便随温度升高增大耐热性纯氧中为720-800度,空气中为850-1000度表面性质接触角80-120度化学稳定性耐酸碱,化学性质稳定用途及加工技术用途装饰用金刚石；高硬度及良好导热性及半导体性能方面的工业用途选矿方法淘洗、跳汰及重介质选矿；X射线、磁电选、浮选含金伯利岩的金刚石选矿23届国际矿物加工会议(土耳其)荣誉报告V.А.ChanturiyaInstituteofComplexExploitationofMineralResources,RussianAcademyofSciences(IPKON),Moscow,RussiaNowadays,diamondminingproceedsin26countriesworldwide,with62%oftheworlddiamondproductionamountaccountedforbythreeleaders:Botswana(27%),Russia(20%),andRepublicofSouthAfrica(15%).Duringthepastfiveyears,totalcashvalueofannuallyproducednaturaldiamondsvariedbetweenUS$7blnandUS$8.5bln.(Figure1)(Morozkin,2005).1INTRODUCTION2RESULTSANDDISCUSSIONThepresentlyemployedtechniquesofextractingdiamondsfromprimaryandplacerdepositsareessentiallybasedupon(andinevitablyconstrainedby)theparticularpropertiesofdiamond(asthemajorvaluablecomponentbeingextracted).Withtheaveragediamondgradeofprimarydiamonddepositsupto1caratperton(2*10-5%)andthegenerallyalmost100%diamondconcentratedesiredasafinalproduct,thedegreeofconcentrationmustbeashighas5*106.Thesetoffactorsessentiallydictatingthechoiceofprocessingtechniquesandequipmentfordiamondconcentrationincludesthehighspecificweightofdiamondascomparedtothatofthebulkofhostrockandassociatedminerals,thenaturalhydrophobicityofdiamond,theХ-rayluminescencepropertiesofthismineral.Diamondrecoverywouldthusbeexpectedtovarybetween92%and98%.Asofnow,dense-media(DM)hydrocycloneseparationisthemostcommonlyusedgravityconcentrationprocess,andХ-rayluminescence(XRL)separationisthemost-usedautomaticsortingtechnique.RussiaholdspriorityinscientificsubstantiationofthehighefficiencyofXRLseparationfordiamond-bearingkimberliteprocessing,aswellasinindustrialimplementationofthistechnique.Inaddition,jigginginMO-318air-drivenpulsatingjiggersisefficientlyusedinRussianpracticeofgravitationaldiamondconcentrationwhendealingwith-5+2mmproducts.thecommonlyacceptedflowchartofdiamond-bearingoreprocessingconsistsofthefollowingoperations:primary(coarse)crushing,scrubbingandscreening,secondarycrushing(grinding),DM-separation,re-crushinginhigh-pressurerollcrushers(HPRC),magneticseparation,X-rayluminescenceseparation,handsortingandjettransportofresultantdiamonds.Frothseparationisusedintheyieldof-1mmgrains.Inaddition,greased-surfaceseparationisusedtore-extractdiamondsfromthe-6+3mmand-3+1mmX-rayluminescenceseparationtailingsandfrothseparationtailings.PrimaryprocessingofdiamondorespreferentiallyinvolvesDMStechniques(dense-mediahydrocycloneseparation)havingthefollowingadvantages:-usefulnessincaseswheretheinitialfeedstockispre-gradedintojusttwosizeclasses,whichisinadequateforXRLseparation;-highproductionrateofdense-mediahydrocyclones,whichmaybeashighas250tonsperhourwithrespecttoinitialfeedtothehydrocyclone(D=800mm);-highseparationcapabilityoftheapparatus(nearlyperfectwhenconcentratinglargediamondsandsatisfactorywhendealingwithsmalldiamondcrystals)-possibilityofoperationwithsuspensionscharacterizedbydensityvalueslowerthantheseparationdensity,whichusuallyvariesbetween3.1and3.2tons/m3;-lowyieldofheavyfractionfromthehydrocyclone(notmorethan6%)andhighdiamondrecoveryintotheheavyfraction(notlowerthan97%).Thepromiseforfurtherenhancementofdiamondoreprocessingefficiency:-developmentofleast-destructiveblastingtechniquesandadvancedmethodsforrecognitionandextractionofdiamondcrystalsintheprocessesofcrushingandconcentrationofdiamond-bearingkimberliteores;-developmentofelectrochemicalwatertreatmenttechniquesdesignedtoproduceelectrolyticproductswithpresetpropertiesmeantforuseindense-media,XRLandfrothseparationprocesses;-creationofopticalsystemsm