沸石论文：沸石及其改性材料处理蓄电池铅酸废水的研究

沸石论文：沸石及其改性材料处理蓄电池铅酸废水的研究【中文摘要】铅是毒性较强的重金属物质,在现代的工农业生产中用途广泛,许多工业排放的含铅三废物质进入环境,其超出环境容量而产生的环境问题日益受到重视。在这些产生铅污染的工业中,铅酸蓄电池生产是一项重要的污染来源。硅碳素(ANJ·SIC)是一种是一种有效的吸附-离子交换基体,由沸石改性而成,成本低廉,再生容易,已经证实硅碳素对于地下水除铁除锰可达到较高的处理效率。本文就以哈尔滨光宇铅酸蓄电池厂产生的废水作为处理对象,对比沸石及其两种改性材料(即硅碳素)的处理效果,对人工配水进行静态实验因素优化,并对吸附饱和后的材料进行再生研究,对除铅前后的材料进行分析,确定其除铅机理。在此基础上研究以吸附材料过滤为核心的一套处理工艺用于处理蓄电池铅酸废水的铅污染。通过静态实验因素优化发现,三种材料处理含铅废水均有较高的去除率,三者相比,1号改性材料的除铅效果最佳。对于100ml含铅浓度为10mg/L的废水,仅需0.5g、在废水pH值大于4.62的条件下于25℃的恒温水浴中振荡30min即可获得98%以上的稳定去除率。通过正交试验可知,四种因素中,废水的pH值影响最大,吸附剂投加量、温度和时间的影响程度则因材料而异。对除铅过程进行了吸附热力学和动力学的研究,发现L型和F型吸附等温线拟合效果均较好,材料除铅是自发吸热过程,拟二级动力学模型能很好的拟合除铅过程。好的吸附材料需要有持久的使用性能,因此考察吸附材料达到饱和后的再生能力。实验发现,采用1MNaOH溶液,以20ml:1g的再生剂与吸附剂的比例于室温下再生1h,三种材料即可获得较好的再生效果,其中1号改性材料的再生效果更佳,其一次再生后的饱和容量可达31mg/L以上,比原沸石还高。在NaOH的基础上加入NaCl,则可改善再生效果。在此基础上对饱和材料连续进行了连续5次饱和再生,1号改性材料再生效果最好,5次再生后仍具有23mg/g的除铅容量。对除铅前后的材料的变化进行分析,发现材料的成分和结构并无显著改变,沸石除铅主要是通过铅进入材料的骨架内部,而改性材料主要是借助于改性表面的基团与铅离子反应实现除铅。考察材料除铅过程中吸附与离子交换的贡献大小,在低浓度含铅废水中,离子交换作用与吸附作用相当且以Ca2+和Na+为主要的交换离子,随着初始浓度的增大及除铅时间的延长,吸附作用逐渐增强。蓄电池铅酸废水酸性强,含铅浓度高,硫酸根浓度大。确定以1号改性材料作为吸附剂,采用中和-砂滤-吸附的工艺实现除铅,当吸附柱填充70cm3吸附剂时,调节废水的停留时间为5min、10min、20min,可分别运行10d、18d、32d。当吸附剂达到饱和后采用不同的再生方式对其进行再生,以1MNaOH与1MNaCl的混合溶液,在750ml/h的滤速下再生2h的效果最好,衰减度仅达8%。采用此种再生方式再生5次,吸附容量衰减到59%,且前四次再生的衰减度较小,仅为27%。【英文摘要】Leadisakindofheavymetalwithgreattoxic.Whileitwasbroadlyusedinindustryandagricultureproduction,wastesincludingleadintoenvironmenthaveoverlapthecapacityofenvironmentandcauseseriousenvironmentalproblem,ofalltheindustydischarginglead,lead-acidaccumulatorproductionisoneofthemostimportantpollutionsource.ANJ.SICisaneffectivematerialwithadsoptionandionexchangecapacity,whichismodifiedfromzeolite,cheapandeasytoregenerate.ithasbeentestifiedthatANJ.SICcouldremoveIronandManganesefromgroundwaterefficiently.ThispapertakewastewateroftheGuangyulead-acidaccumulatorproductionindustyastheobject.Putzeolite,andtwokindsofmodifiedzeolite(ANJ.SIC)intodealingwiththemanualwastewater,optimizethefactorthatcouldeffectthetreatmentefficiencyanddiscusstheregenerationeffectofthesaturatedmaterial.Comparingthechangeofmaterialbeforeandafteradsorptionandmakesureitsmechanismofleadremoval.Then,studyonthetreatmentofthelead-acidaccumulatorwastewaterwithaserialofprocessinwhichadsorptionwasthemainprocedure.Aftertheoptimizationofthefactor,thethreematerialallcantreatthewasterwaterbearingleadatahighremovalrate.Bycomparison,thefirstmodifiedmaterialwasthebest.Tothewasterwater100mlwithleadat10mg/L,itcanreachthesteadyremovalrateover98%at25℃withthedosageof0.5g,pH4.62.Byconductingorthogonalexperiment,wecanfindthatpHisthemostinfluencialfactor,theimpactofadsorbentdosage,temperatureandadsorptiontimevariedwiththeadsorbents.ReasearchtheThermodynamicsandKineticsoftheadsoption,LangmuirandFreundlichAdsorptionisothermbothwellfitted.Theadsoptionisaendotherrmicandspontaneousreaction,Pseudosecondorderkineticsmodelcanfittheprocesswell.Goodabsorbentshouldbedurable,soweinvestigatetheirregenerationability.ifadoptingNaOHin1Mastheregenerant,withtheratiotoadsorbentat20ml:1g,regeratefor1hattheroomtemperatue,threeadsorbentsallcouldregeneratewell,whilethefirstmodifiedzeolitewasthebest.Itscapacityafterthefirstregenerationcanreach31mg/g,evenlargerthantherawzeolite.AddNaClintoNaOHcouldimprovetheregenerationeffect.AdoptingNaOHandNaOHwithNaClasregeneranttoregerateforfivetime.Thefirstmodifiedzeolitewasthebest,itssaturatedcapacitywas23mg/gafterfiveregeration.Analysisthechangeofthematerialbeforeandaftertheadsoption,wefoundthatthestructureandcontentsofthematerialdidnotchangemuch.leadremovalwithzeotilemainlythroughleadinvolvedintotheframework,whilethemodifiedzeolitereactwithleadatthesurfacetoremoveleadfromthewastewater.Observingtheionchangeinthewastewatertodecidethecontributeratioofadsoprionandionexchangeinleadremoval.Inthewastewaterwithleadinlowconcentration,ionexchangeandadsoptionbothimportantinleadremoval,withNa+andCa2+asthemainiontoexchange.Theroleofadsoprioninleadremovalstrengthenwiththeconcentrationofleadincreasedandtheadsoptiontimeprolonged.Theacidity,leadandSulfateconcentrationofWastewaterfromlead-acidstoragebatteryproductionindustywasquitelarge,sowechoosethefirstmodifiedmaterialastheadsorbent,takelime-sandfilter-adsorptiontoremoveleadfromthewastewater.Tothefiltrationcolumnwiththefirstmodifiedzeoliteof70cm3,adjustthefiltrationratetomaketheHRTat5min,10minand20min,thecolumncouldrunfor10d,18dand32drespectively.Afterthematerialsaturated,wetakedifferentregenrationmode,ofwhichwithNaOHandNaClof1Mastheregererant,adjustregererationflowrateat750ml/hfor2hcouldgetthebestregenerationeffect.Afterregenerationtheleadremovalcapacityonlyreduceat8%,Adoptingthisregenerationmodetooperateforfivetimes,thecapacityreduceto59%,whiletheattenuationofleadremovalcapacityisonly27%inthefirstfourregeneration.【关键词】沸石改性再生铅酸废水【英文关键词】zeolitemodificationregenerationlead-acidwastewater【目录】沸石及其改性材料处理蓄电池铅酸废水的研究摘要3-5ABSTRACT5-6第1章绪论10-221.1课题来源及研究背景10-111.1.1课题来源101.1.2研究背景10-111.2铅污染治理的国内外研究现状11-151.2.1化学沉淀法11-121.2.2吸附法12-131.2.3离子交换法13-141.2.4膜处理法141.2.5植物修复法141.2.6其他方法14-151.3沸石的特性及应用现状15-181.3.1沸石的特性15-