2009届毕业设计(论文)课题名称:干法氟化铝生产简介系、部:材料与化学工程系学生姓名:林兰指导教师:李昶红职称:副教授专业:应用化工技术班级:应化0601班学号:7020601092009年5月摘要氟化铝(AlF3)是铝电解生产过程中的一种主要辅助材料(主要用作于铝电解的助熔剂,用于调整电解槽电解质的分子比水平),其含水量对电解铝生产和净化过程影响很大。中国是二十世纪九十年代引进瑞士Buss干法工艺,并建成了无水氟化铝生产线。无水氟化铝具有主含量高、水分低、堆积比重大的特点,特别适用于电解槽启动后降低电解质分子比。与湿法产品相比,无水氟化铝在使用中有以下优点:a、主含量在90%以上,高出湿法产品近5个百分点,杂质含量低,节约了氟化铝用量,降低了生产成本,有利于提高原铝质量。b、水分含量低,小于1.0%,远远低于湿法产品水分7.0%的水平,在电解过程中使用无水氟化铝产品,AlF3几乎不发生水解反应,其可利用的有效成份远远高于湿法产品。更为主要的是避免了使用湿法产品因氟化铝的水解造成的操作环境恶劣的状况,有利于环境保护。总之,干法工艺流程短,工艺紧凑;原料消耗低;环境污染少,产品质量好等。本文主要介绍氟化氢—无水工艺法制备干法氟化铝工艺及控制方案。干法氟化铝按工艺流程分为氟化氢制备(包括酸给料、萤石给料、氟化氢反应炉)及氟化铝制备包括流化床、尾气处理、成品处理。流程如下:1.萤石(CaF2)粉料与浓硫酸(98%)及发烟硫酸(104.5%)的混合物在反应炉里反应生成HF气体与石膏(CaSO4)。2.HF气体经净化后在流化床内与干燥的Al(OH)3反应生成AlF3,AlF3经冷却后送至成品库,尾气经中央吸收处理后放空。关键词:干法工艺;萤石;氟化铝;反应炉;氟化铝反应器;中央吸收AbstractThealuminumfluoride(AlF3)isinthealuminumelectrolysisproductionprocessonemainaccessorymaterial(mainlyservesasinaluminumelectrolysisflux,usesinadjustingelectrictankelectrolytemolecularproportionlevel),itswatercontentisverybigtotheelectrolyticaluminiumproductionandthepurificationprocessinfluence.theChinawasthe1990sintroducestheSwissBussdryprocesscraft,andhascompletedtheanhydrousaluminumfluorideproductionline.Theanhydrousaluminumfluoridehasthemaincontenttobehigh,themoisturecontentislow,thestackproportionmajorcharacteristic,issuitablespeciallystartsaftertheelectrictankreducestheelectrolytemolecularproportion.Compareswiththeaqueousmethodproduct,theanhydrousaluminumfluoridehasthefollowingmeritintheuse:a,thehostcontentabove90%,washigherthantheaqueousmethodproductnearly5percentagepoints,theforeigninclusionislow,savedthealuminumfluorideamountused,reducedtheproductioncost,wasadvantageousinraisestheplateaualuminumquality.b,themoisturecontentislow,issmallerthan1.0%,islowerthantheaqueousmethodproductmoisturecontent7.0%levelsbyfar,usestheanhydrousaluminumfluorideproductintheelectrolysisprocess,AlF3doesnothavethehydroliticreactionnearly,itsmaytheuseactiveprinciplebehigherthantheaqueousmethodproductbyfar.Whatismoremainhasavoidedtheoperatingenvironmentbadconditionwhichbecausetheuseaqueousmethodproductthealuminumfluoridehydrolisiscreated,wasadvantageousintheenvironmentalprotection.Inbrief,thedryprocesstechnicalprocessisshort,thecraftiscompact;Theconsumptionofmaterialislow;Theenvironmentalpollutionarefew,productqualitygoodandsoon.Thisarticlemainintroductionhydrogenfluoride-anhydrouscraftlawpreparationdryprocessaluminumfluoridecraftandcontrolplan.Thedryprocessaluminumfluoridedividesintothehydrogenfluoridepreparationaccordingtothetechnicalprocess(includingacidtomaterial,fluorspartogivematerial,hydrogenfluoridereactor)andthealuminumfluoridepreparationincludingthefluidbed,exhaustprocessing,endproductprocessing.Theflowi...