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1、环境工程吉红洁S20120436StudyofRemediationofSoilContaminedwithHeavyMetalsbyCoalFlyAsh关于粉煤灰修复土壤重金属污染的研究ABSTRACT摘要Thelabilefractionofheavymetalsinsoilsisthemostimportantfortoxicityforplants.Thusitiscrucialtoreducethisfractionincontaminedsoilstodecreasethenegativeeffectofhea
2、vymetals.Inanexperiment,theeffectsoftwoadditivesonthelabilefractionsofCu,MnandZnwereinvestigatedinasoilcontaminedduringlong-termapplication.Theadditiveusedwasthecoalflyash.Thetreatedsoilwasfurtherenrichedwithheavymetalsandallowedtoageatroomtemperaturefor30days.Aft
3、erthisperiod,theywereextractedplant-available(EDTA;HNO3;CH3COOH)metalspecies.Theadditionofflyashstronglyreducedtheplant-availableofMnforplantsbuttoalesserextentthisappliestotheplant-availableofCuandZnforplants.Byadditionof1%offlyashaswellas2%offlyash,thelabilefrac
4、tionofCu,MnandZnwereloweredby6.3,145.0and29.7mg×kg–1,respectively.MoreoveressentialcorrelationbetweentotalCuandZncontentswasstatedinthesoilwithplant-availablecontentofmetals,withreferencetobothmetals.Valueofcoefficientsofcorrelationisattestingtoitbetweenthetotalan
5、dplant-availableCuandZncontentswhicharerespectivelyequal:R(Cu)=0.845,R(Mn)=0.864andR(Zn)=0.872forp=99.5%.TheresultssuggestedthatleadingintothesoiloftheadditionalamountofflyashcanbeaneffectivewayofchemicalremediationwithreferencetosoilscontaminatedbyCuorMnorZn.Beca
6、usehecausesimmobilizationofexaminedheavymetalsinthesoilandintheprocessinthearrangementa—soilislimitingtheavailabilityofthesemetalsplantandmoredistantbondsofthefoodchain.土壤中重金属的不稳定部分对植物来说是最重要的毒性。因此在降低土壤重金属的负面影响方面,减少污染土壤中的这部分是至关重要的。在同一个实验中,两种添加剂在铜、锰和锌的不稳定部分的影响应在土壤污染
7、中长期应用。使用的添加剂是粉煤灰。经过处理的土壤是进一步富含重金属并且室温下成熟30天。经过该阶段,它们被提取植物可用(乙二胺四乙酸;硝酸;乙酸)金属物种。粉煤灰的添加强烈降低了锰和锌的植物可用性,但在较小程度上这也适用于铜和锌的植物可用性。通过添加1%的粉煤灰以及2%的粉煤灰,铜、锰和锌的不稳定部分分别被降低了6.3,145.0和29.7毫克/公斤。而且土壤中铜和锌总含量的基本相关性被规定,包括两种金属的植物可用性。相关性系数值证明它在植物可用铜和锌总含量平的:R(铜)=0.845,R(Mn)=0.864和R(锌)=0.
8、872,p=99.5%。结果表明,土壤中主要的额外数量的粉煤灰是一种化学修复的有效途径,参照土壤污染的锰、铜或锌。因为他引起土壤重金属检测的固定化——限制了这些金属厂的可用性和更远食物链的联合。Keywords:SoilRemediation;HeavyMetals;CoalFlyAsh;FAAS火焰原