海水预处理

海水预处理系统SeaWaterPretreatmentSystem西北发电运行有限责任公司ShaanxiNorthwestPowerGenerationOperationCo.,Ltd.海水预处理系统流程SeaWaterPretreatmentSystemFlowSeawaterSedimentation&TreatmentSystemSeawaterDistributionSystemSludgeDischargeSystemSeawaterStorageSystemSeawaterPumpingandFilteringSystemSludgeTransportationSystemTobedischargedintorainwaterdrainSeawaterPretreatmentDosingSystemSeawaterMEDSeawaterDesalinationSystemCompressedAirSystemandFlushingSystem海水预处理设备图示GraphicDisplayofSeaWaterPretreatmentEquipment孔板式净水混合器设备图示DrawingofOrificePlatePurifiedWaterMixer海水预处理设备图示GraphicDisplayofSeaWaterPretreatmentEquipment小孔眼格网设备图示DrawingofSmallorificeGrids海水预处理设备图示GraphicDisplayofSeaWaterPretreatmentEquipment小间距斜板设备图示DrawingofSmall-SpacingSkewPlate海水预处理设备图示GraphicDisplayofSeaWaterPretreatmentEquipment自动冲洗过滤器设备图示DrawingofAutomaticFlushingFilter海水预处理设备图示GraphicDisplayofSeaWaterPretreatmentEquipment沉淀池设备外形图Externalviewofsedimentationbasinequipment混凝原理CoagulationPrinciple凝聚和絮凝的全过程称为混凝。Thewholeprocessofcoagulationandflocculationiscalledcoagulation.（1）胶体的脱稳凝聚(1)Destabilizationandcoagulationofcolloid向水中投加电解质，可起到压缩双电层使胶体脱稳的作用。其主要机理是向水中加入铝盐或铁盐混凝剂后，水中胶体颗粒的双电层被压缩或电性中和而失去稳定性。将混凝剂与原水快速均匀混合并产生一系列化学反应而脱稳，这一过程所需时间很短，一般在1min左右。一些阳离子型的高分子聚合物也能对水中胶体起到脱稳凝聚作用，这类高分子聚合物在水中呈长链结构，带有正电荷，它们对水中胶体的脱稳凝聚是由于范德华力吸附和静电引力共同作用的。Puttingelectrolyteintowatercanplayafunctionofcompressingelectricdoublelayertocausecolloidtolosestability.Themainmechanismiselectricdoublelayerofcolloidalparticleslosestabilitybecausetheyarecompressedortheirelectricalpropertiesareneutralizedafteraluminumsaltorferricsaltcoagulantisaddedinwater.Mixcoagulantwithrawwaterevenlyandquicklytoproduceaseriesofchemicalreactionstogetthepurposeofdestabilization;thisprocessneedsashorttimewhichisgenerally1min.orso.Somecationtypemacromoleculepolymerscanhavetheeffectofdestabilizationandcoagulationoncolloidinwater.Thistypeofmacromolecularpolymersareinalongchainstructureinwaterandhavepositivecharges.ThedestabilizationandcoagulationeffectoncolloidbymacromolecularpolymersaredonebyVanderWaalsforceabsorptionandelectrostaticattractiveforcetogether.混凝原理CoagulationPrinciple（2）絮凝和絮凝物（矾花）的形成(2)Formationofflocculationandfloc水中胶体经脱稳凝聚形成的初始絮凝物的粒径一般在1µm以上，这时布朗运动已不能推动它们碰撞而形成更大的颗粒。为了使初始絮凝物互相碰撞而粘合成大颗粒的絮凝体，需要另外向水中输入能量，产生速度梯度。有时需向水中加入有机高分子絮凝剂，利用絮凝剂长链分子的吸附架桥作用提高碰撞产生粘合的几率。絮凝效率通常随絮凝物浓度和絮凝时间的增加而提高。Theparticlesizeofinitialflocformedthroughdestabilizationandcoagulationofcolloidsinwaterisgenerallymorethan1µm;Brownianmovementcouldnotdrivethemtocollidewitheachothertoformbiggerparticlesatthistime.Inordertoinitialfloccollidewitheachothertoagglutinatebigfloc,energyneedstobeputinwateradditionallytoproducevelocitygradient.Sometimes,organicmacromolecularflocculentneedstobeaddedinwaterandmakeuseoftheabsorptionandbridgingfunctionoflong-chainmoleculesofflocculenttoimprovetheprobabilityofagglutinationproductionbecauseofcollision.Flocculationefficiencyisimprovedwiththeincreasesoftheflocconcentrationandflocculationtime.常用的混凝药剂简介BriefIntroductionofCommonCoagulants为了提高混凝处理的效果，必须选用性能良好的药剂，创造适宜的化学和水力学条件。常用的混凝剂主要分为铝盐和铁盐两类，铝盐中以硫酸铝和聚合铝为主，铁盐中以三氯化铁和聚合硫酸铁居多。铁盐与铝盐相比，铁盐生成的絮凝物密度大，沉降速度快，pH适应范围宽；混凝效果受温度的影响比铝盐小；但投加铁盐时要注意，设备运行不正常时，带出的铁离子会使出水带色，并可能污染后续水处理除盐设备，如阴离子交换树脂。Inordertoimprovecoagulationtreatmenteffect,itmustchoosechemicalswithgoodperformancesandcreatesuitablechemicalandhydraulicsconditions.Commoncoagulantsaremainlydividedintoaluminumsaltandferricsalttwotypes.Aluminumsulfateandpolymericaluminumtakeapriorityinaluminumsalt;ferricchlorideandpolymericferricsulfatetakeamainpartinferricsalt.Comparingwithaluminumsalt,thedensityofflocproducedbyferricsaltisbig;thesedimentationvelocityisfast;pHapplicationrangeiswide;theinfluencecausedbytemperatureoncoagulationeffectisweakerthanthatofaluminumsalt.However,itshouldnoticethatironionstakenoutwillcausewatertohavecolorandmightpollutesequentialwatertreatmentdemineralizationequipmentsuchasanionexchangeresiniftheequipmentisinabnormaloperationduringaddingferricsalt.常用的混凝药剂简介BriefIntroductionofCommonCoagulants硫酸铝AluminumsulfateAl2(SO4)3·18H2O含无水硫酸铝52%～57%Including52%～57%anhydrousaluminumsulfatepH=6～8的原水pH=6～8rawwater投加量较大时，处理后水中强酸阴离子含量明显增加Thecontentofstrongacidanioninwaterobviouslyincreaseaftertreatmentwhendosageisgreat.不适用于低温、低浊度的原水Notsuitableforlowtemperatureandlowturbidityrawwater碱式氯化铝（PAC）Basicaluminumchloride(PAC)Aln(OH)mCl3n-m(通式)Aln(OH)mCl3n-m(Generalformula)是无机高分子化合物Itisanorganicmacromolecularcompound.适用原水浊度范围较宽，可用于低温、低浊水的处理，pH适用范围为5～9Ithasawiderturbidityapplicationrangeforrawwaterandcanbeusedforlowtemperatureandlowturbiditywatertreatment;theapplicationrangeofitspHis5～9.净化效率高，投药量少，出水水质好Purificationefficiencyishigh;chemicaldosageislittleandwaterqualityofoutletwaterisgood.使用时操作方便，腐蚀性小，劳动条件好Theoperationisconvenient;corrosivenessisweakandworkingconditionsaregood.有固体产品和液体产品之分Itisdividedintosolidproductandliquidproduct.常用的混凝药剂简介BriefIntroductionofCommonCoagulants硫酸亚铁FerroussulfateFeSO4·7H2O适用碱度高、浊度高、pH=8.1～9.6的原水，或与石灰处理配合使用ItissuitableforrawwaterwhosealkalinityandturbidityarehighandpH=8.1～9.6,oritisusedcooperatingwithlimetreatment