《湿法冶金过程及设备培训》-净化的原料及产品答疑

一、常见重点问题答疑I.AnswerstoFrequentlyAskedKeyQuestions1.请分别定义净化的原料和产品，并列举硫酸锌溶液净化中产品的两种主要类型及其核心特点。1.Pleasedefinetherawmaterialsandproductsforpurificationrespectively,andlistthetwomaintypesofproductsinzincsulfatesolutionpurificationandtheircorecharacteristics.解答：（1）净化的原料：指通过各种浸出过程得到的金属化合物溶液，是净化工序的处理对象（如硫酸锌中性浸出液）。Answer:(1)Rawmaterialsforpurification:Refertothemetalcompoundsolutionobtainedthroughvariousleachingprocesses,whichisthetreatmentobjectofthepurificationprocess(suchaszincsulfateneutralleachingsolution).（2）净化的产品：指经净化处理后得到的物质，主要包括两类：(2)Purifiedproducts:Refertothesubstancesobtainedafterpurificationtreatment,mainlyincludingtwocategories:①净化液：满足后续工序（如电积）要求的溶液，核心特点是主体金属浓度稳定（如硫酸锌净化液中Zn130-180g/L）、杂质含量低于限值（如Cu≤0.5mg/L、Co≤3mg/L）。①Purificationsolution:Asolutionthatmeetstherequirementsofsubsequentprocesses(suchaselectrowinning).Thecorefeaturesarethattheconcentrationofthemainmetalisstable(suchasZn130-180g/Linthezincsulfatepurificationsolution)andtheimpuritycontentislowerthanthelimitvalue(suchasCu≤0.5mg/L,Co≤3mg/L).②净化渣：含有被去除的杂质或可回收有价金属的固体残渣，核心特点是富集特定杂质（如Cu-Cd渣、钴渣），具有回收利用价值。②Purificationslag:Referstosolidresiduecontainingremovedimpuritiesorrecoverablevaluablemetals.Itscorefeatureistoenrichspecificimpurities(suchasCu-Cdslagandcobaltslag),whichhasrecyclingvalue.2.某硫酸锌中性浸出液的成分如下：Zn150g/L、Cu0.8g/L、Cd0.5g/L、Ca2.0g/L、Cl0.3g/L。请说明该原料的成分特点，对比锌电积对净化后液的典型标准，并对其中的杂质进行分类。2.Thecomponentsofazincsulfateneutralleachingsolutionareasfollows:Zn150g/L,Cu0.8g/L,Cd0.5g/L,Ca2.0g/L,Cl0.3g/L.Pleaseexplainthecompositioncharacteristicsofthisrawmaterial,comparethetypicalstandardofzincelectrowinningforpurifiedliquid,andclassifytheimpuritiesinit.解答：（1）原料成分特点：主体金属为Zn（150g/L），含有多种杂质（Cu、Cd、Ca、Cl等），杂质浓度远高于后续工序要求。Answer:(1)Characteristicsofrawmaterialcomposition:ThemainmetalisZn(150g/L),whichcontainsavarietyofimpurities(Cu,Cd,Ca,Cl,etc.),andtheimpurityconcentrationismuchhigherthantherequirementsofsubsequentprocesses.（2）锌电积对净化后液的典型标准：Zn130-180g/L、Cu≤0.5mg/L、Cd≤0.8mg/L、Ca≤1.5g/L、Cl≤0.05g/L。(2)Typicalstandardsforzincelectrowinningonpurifiedliquid:Zn130-180g/L,Cu≤0.5mg/L,Cd≤0.8mg/L,Ca≤1.5g/L,Cl≤0.05g/L.（3）杂质分类：第一类（影响产品质量）：Cu、Cd（会导致电积锌纯度下降）；第二类（阻塞管道）：Ca（易结晶沉积，堵塞管道和溜槽）；第三类（干扰电积）：Cl（腐蚀阳极板，缩短其使用寿命）。(3)Impurityclassification:CategoryI(affectingproductquality):Cu,Cd(willleadtoadecreaseinthepurityofelectrowinnedzinc);CategoryII(blockingpipes):Ca(pronetocrystallinedeposition,blockingpipesandchutes);CategoryIII(interferingwithelectrowinning):Cl(corrodingtheanodeplate,shorteningitsservicelife).3.针对硫酸锌溶液中的Cu、Co、Cl三种杂质，分别说明对应的净化方法及得到的净化液和净化渣的特点。3.PleaseexplainthecorrespondingpurificationmethodsandthecharacteristicsoftheobtainedpurificationliquidandpurificationresiduerespectivelyaccordingtothethreeimpuritiesofCu,CoandClinzincsulfatesolution.解答：Answer:（1）Cu杂质：1)Cuimpurity:①净化方法：锌粉置换法（反应：CuSO₄+Zn=ZnSO₄+Cu↓）；①Purificationmethod:Zincdustprecipitation(reaction:CuSO₄+Zn=ZnSO₄+Cu↓);②产品特点：净化液中Cu≤0.5mg/L；净化渣为Cu-Cd渣（含Cu、Cd等有价金属，可回收）。②Productfeatures:Cuinpurificationliquid≤0.5mg/L;thepurificationslagisCu-Cdslag(containingvaluablemetalssuchasCuandCd,whichcanberecycled).（2）Co杂质：(2)Coimpurity:①净化方法：黄药法（黄酸钾与Co²⁺反应生成黄酸钴沉淀）；①Purificationmethod:Xanthatemethod(potassiumxanthatereactswithCo²⁺toformcobaltxanthateprecipitate);②产品特点：净化液中Co≤3mg/L；净化渣为钴渣（富集Co，具有回收价值）。②Productfeatures:Coinpurificationsolution≤3mg/L;Thepurifiedslagiscobaltslag(enrichedinCo,whichhasrecoveryvalue).（3）Cl杂质：(3)Climpurity:①净化方法：硫酸银沉淀法（反应：Ag₂SO₄+2Cl⁻=2AgCl↓+SO₄²⁻）；①Purificationmethod:Silversulfateprecipitationmethod(reaction:Ag₂SO₄+2Cl⁻=2AgCl↓+SO₄²⁻);②产品特点：净化液中Cl≤0.05g/L；净化渣为氯化银渣（可通过还原法回收Ag）。②Productfeatures:Clinpurificationsolution≤0.05g/L;thepurificationresidueissilverchlorideresidue(Agcanberecoveredbyreductionmethod).二、常见难点问题答疑II.AnswerstoFrequentlyAskedDifficultQuestions1.硫酸锌溶液中若Cl⁻浓度超标（如0.5g/L），会对后续锌电积工序造成哪些具体危害？请从设备和生产效率两方面说明。1.WhatspecifichazardswillitcausetothesubsequentzincelectrowinningprocessiftheCl⁻concentrationinthezincsulfatesolutionexceedsthestandard(suchas0.5g/L)?Pleaseexplainfromtwoaspectsofequipmentandproductionefficiency.解答：Cl⁻浓度超标对锌电积的危害如下：Answer:ThehazardsofexcessiveCl⁻concentrationtozincelectrowinningareasfollows:（1）设备方面：Cl⁻具有强腐蚀性，会加速铅阳极板的腐蚀（生成可溶性铅氯化物），缩短阳极板使用寿命，增加设备更换成本；同时可能腐蚀电解槽槽体，导致电解液泄漏。(1)Equipment:Cl⁻ishighlycorrosive,whichwillacceleratethecorrosionofleadanodeplates(generatesolubleleadchloride),shortentheservicelifeofanodeplates,andincreaseequipmentreplacementcosts;atthesametime,itmaycorrodetheelectrolyticcellbody,resultinginelectrolyteleakage.（2）生产效率方面：Cl⁻在阳极放电生成Cl₂气体，污染车间环境并腐蚀电极接线；此外，Cl⁻会降低电解液的导电率，增加槽电压，导致电能消耗上升，电流效率下降。(2)Intermsofproductionefficiency:Cl⁻dischargesattheanodetogenerateCl2gas,whichpollutestheworkshopenvironmentandcorrodeselectrodewiring;inaddition,Cl⁻reducestheelectrolyteconductivityandincreasesthecellvoltage,resultinginanincreaseinelectricenergyconsumptionandadecreaseincurrentefficiency.2.某硫酸锌原料中Co²⁺浓度高达50mg/L（远高于电积要求的3mg/L），且含有少量Cu²⁺（0.3g/L）。应优先选择哪种方法除Co？说明选择依据及与原料杂质特点的匹配性。2.TheCo²⁺concentrationinazincsulfaterawmaterialisashighas50mg/L(muchhigherthantheelectrowinningrequirementof3mg/L),anditcontainsasmallamountofCu²⁺(0.3g/L).WhichmethodshouldbepreferredtoremoveCo?Explaintheselectionbasisandthematchingwiththeimpuritycharacteristicsofrawmaterials.解答：应优先选择黄药法除Co。Answer:ThexanthatemethodshouldbepreferredtoremoveCo.（1）选择依据：黄药（如丁基黄药）与Co²⁺反应生成难溶的黄酸钴沉淀（Ksp极小），可将Co²⁺从50mg/L降至3mg/L以下，适用于高浓度Co⁺的深度去除。(1)Selectionbasis:Xanthate(suchasbutylxanthate)reactswithCo²⁺toformaninsolublecobaltxanthateprecipitate(Kspisextremelysmall),whichcanreduceCo²⁺from50mg/Ltolessthan3mg/L.ItissuitablefordeepremovalofhighconcentrationsofCo⁺.（2）与原料杂质的匹配性：原料中含少量Cu²⁺，而黄药对Cu²⁺也有沉淀作用（生成黄酸铜），可同步去除部分Cu²⁺，减少后续锌粉置换除Cu的负荷，与原料杂质特点匹配度高。(2)Matchingwithrawmaterialimpurities:TherawmaterialcontainsasmallamountofCu²⁺,andxanthatealsohasaprecipitationeffectonCu2⁺(generatingcopperxanthate),whichcansimultaneouslyremovepartofCu²⁺andreducetheloadofsubsequentzincdustprecipitationtoremoveCu.Ithasahighdegreeofmatchingwiththeimpuritycharacteristicsofrawmaterials.3.在硫酸锌溶液净化中，若采用锌粉置换法除Cu时锌粉过量（超过理论用量的50%），会对净化液和后续电积工序产生哪些影响？请说明影响路径。3.WhatimpactwillithaveonthepurifiedsolutionandthesubsequentelectrowinningprocessinthepurificationofzincsulfatesolutionwhenthezincpowderreplacementmethodisusedtoremoveCuincaseofanexcessiveamountofzincpowder(morethan50%ofthetheoreticaldosage)?Pleasespecifytheimpactpath.解答：锌粉过量的影响及路径如下：Answer:Theeffectsandpathsofexcessivezincpowderareasfollows:（1）对净化液的影响：过量锌粉未完全反应，会以金属锌颗粒形式残留于净化液中，导致净化液中悬浮固体增多。(1)Effectonthepurificationliquid:Excesszincpowderisnotcompletelyreactedandwillremaininthepurificationsolutionintheformofmetalliczincpartic