WHEREMUISTHETOTALMAKEUPWATERFLOW,WHICHISTHESUMOFEVAPORATIONANDBLOWDOWN,GPM,ANDBDISTHEBLOWDOWNFLOW,GPMSINCETHEAMOUNTOFEVAPORATION,E,ISEASILYCOMPUTEDAS01OFTHECONDENSERWATERFLOWRATEPERDEGREEOFRANGE,MUINEQ136CANBEREPLACEDWITHTHEVALUEETBDEQUATION136CANTHENBEREARRANGEDTOYIELDEQ137BDECYCLES1THUS,AFTERTHENUMBEROFCYCLESISDETERMINEDBASEDONTHEMAKEUPANDDESIREDCONDENSERWATERBLOWDOWNCONCENTRATIONOFDISSOLVEDSOLIDS,THEACTUALBLOWDOWNREQUIREMENTCANBECALCULATEDFROMEQ136SINCEDRIFTWATERLOSSISNOTINCLUDEDINTHESECALCULATIONS,THEACTUALREQUIREDBDFLOWCANBEREDUCEDBYTHEAMOUNTOFDRIFTLOSSFROMTHETOWERTHEREARETWOWAYSOFCONTROLLINGBLOWDOWNINANHVACCOOLINGTOWERSYSTEM1CONSTANTBLOWDOWNWITHMANUALADJUSTMENTBASEDONPERIODICWATERHARDNESSANALYSISISTHESIMPLESTMETHODHOWEVER,SINCETHEAMOUNTOFBLOWDOWNISCONSTANT,THELOSSINWATERANDWATERTREATMENTCHEMICALSISHIGHANDTHISREALLYREPRESENTSTHEMOSTEXPENSIVEAPPROACH2CONTROLLEDBLOWDOWNISBASEDONCONTINUOUSMONITORINGOFTHEWATERHARDNESSASINDICATEDBYITSCONDUCTIVITYAUTOMATICCONTROLMINIMIZESTHEWASTEOFWATERANDWATERTREATMENTCHEMICALSANDISTHEPREFERREDMETHOD,ASDESCRIBEDINSECTION134TABLE133SUMMARIZESTHEWATERFLOWSASSOCIATEDWITHACOOLINGTOWERFORVARIOUSCYCLESOFCONCENTRATIONBASEDON30GPM/TONFLOWFROMTABLE133,ITISCLEARTHATTHEAMOUNTOFMAKEUPWATERISREDUCEDSIGNIFICANTLYASTHENUMBERTABLE133MAKEUPWATERREQUIREMENTASFUNCTIONOFCYCLESCYCLESEVAPORATIONBLOWDOWNMAKEUPMAKEUPGPM/TONGPM/TONGPM/TON2003000030000600100300300001500045075400300001000040067500300000750037563600300000600036060100030000033003335515003000002300323542000300000150031553MU是補給水流動量，這是蒸發和排污的總和,加侖每分鐘和BD是排污流量，加侖每分鐘。自從蒸發流量E很容易計算為01的冷凝器水流速，補給水流動量乘以蒸發流量的意義，方程式可以重新安排趨近于EQBDECYCLES1因此,在確定的周期數是基于變化值期望的冷凝器水排污濃度溶解的固體,實際的排污要求可以計算出EQ。因為水損失不包括在這些計算,實際需要排污流量可以減少損失。有兩種方式控制排污在暖通空調冷卻塔系統1、常數與手動調整排污基于周期性水硬度分析是最簡單的方法。然而,由于數量的排污是常數,損失在水和水處理化學品居高不下,這確實代表了最昂貴的方法。2、控制排污是基于連續監測水硬度顯示其電導率。自動控制最小化浪費水和水處理化學品和是首選方法,如134節中描述。表133總結了水流關聯到一個冷卻塔為各種周期的濃度基于30GPM/噸流。從表133中,很明顯,這個數量的補給水是數量顯著減少表133補給水需求功能的周期周期蒸發量GPM/TON排污量GPM/TON組成GPM/TON組成2003000030000600100300300001500045075400300001000040067500300000750037563600300000600036060100030000033003335515003000002300323542000300000150031553CONDENSERWATERTREATMENTOFCYCLESISINCREASEDFROM2TO6HOWEVER,THEREISONLYAFURTHER5REDUCTIONASTHECYCLESAREINCREASEDFROM6TO10,ANDONLYAFURTHER2REDUCTIONASCYCLESAREINCREASEDTO20THEREFORE,INMOSTCOOLINGTOWERAPPLICATIONS,CYCLESOFCONCENTRATIONAREMAINTAINEDBETWEEN5AND10ASINDICATEDBYTHELSI,RSI,AND/ORPSIANDDEPOSITIONINHIBITORSAREADDEDASNECESSARYWHILELOWERCYCLESREPRESENTLOSSOFMOREWATERANDTREATMENTCHEMICALS,THEAMOUNTOFTREATMENTCHEMICALSREQUIREDTENDSTOGODOWNWITHCYCLES,AND510CYCLESUSUALLYREPRESENTAGOODBALANCEPOINTREDUCTIONOFHARDNESSBYBLOWDOWNOREVENBYWATERSOFTENINGPRETREATMENTMAYNOTELIMINATETHEPOTENTIALFORDEPOSITIONINTHECONDENSERWATERSYSTEMINTHESECASES,CHEMICALTREATMENT,IE,THEADDITIONOFDEPOSITIONINHIBITORSTOTHEWATERSYSTEM,BECOMESNECESSARYWHENADISSOLVEDSALTPRECIPITATESANDDEPOSITSONTHEWETTEDMETALSURFACESOFTHECONDENSERWATERSYSTEM,ITFORMSACRYSTALGROWTHTHATATTACHESITSELFTOMETALSURFACESASITCOMESOUTOFSOLUTIONTHEMOSTCOMMONSCALEINHIBITORSUSEDINCONDENSERWATERSYSTEMSAREPOSPHONATES,WHICHAREORGANICPHOSPHATECOMPOUNDS,SUCHASHEDP,WHICHFUNCTIONBYADSORPTIONONTHECRYSTALSASTHEYFORM,PREVENTINGTHEMFROMATTACHINGTOMETALTHUS,THESECRYSTALSPRECIPITATEOUTOFSOLUTION,USUALLYINTHETOWERBASIN132CORROSIONCONTROL1321GALVANICCORROSIONMETALCORROSIONOCCURSASARESULTOFGALVANICACTIONATANEGATIVELYCHARGED“POLE”ORSITEONTHEMETALSURFACEBOTHANODES,NEGATIVELYCHARGEDSITES,ANDCATHODES,POSITIVELYCHARGEDSITES,CANBECREATEDONTHEMETALDUETOIMPURITIESINTHEMETAL,LOCALIZEDSTRESS,METALGRAINSIZEORCOMPOSITIONDIFFERENCES,OREVENSCRATCHESONTHEMETALSURFACEDUETOTHEDIFFERENCESINCHARGES,THEREISANELECTRICALPOTENTIALBETWEENTHEANODEANDCATHODEANDANELECTRICALCURRENTELECTRONSFLOWSFROMANODESTOCATHODES,USINGTHESURROUNDINGWATERASACONDUCTORORELECTROLYTE,ASSHOWNINFIGURE132FORSTEEL,THEANODICREACTIONISFORTHEIRONTOGIVEOFFTWOFREEELECTRONS,BECOMINGPOSITIVELYCHARGEDTHISPOSITIVELYCHARGEDIRONTHENCOMBINESTWOHYDROXYLRADICALSFROMTHEWATERTOFORMFERROUSHYDROXIDE,WHICHCOMBINESFURTHERWITHTHEWATERTOFROMFERRICHYDROXIDETHAT,WHENDEHYDRATED,ISIRONOXIDEORRUSTATCATHODES,THEELECTRONSGIVENOFFATTHEANODECOMBINEWITHWATERTOYIELDHYDROXYLRADICALS,TOBALANCETHEREACTIONSCORROSION,THENISTHELOSSOFMETALITLITERALLY“DISSOLVES”CORROSIONCANEXHIBITTWOCHARACTERISTICSDEPENDINGONTHEUNDERLYINGREASONFORTHEANODICANDCATHODICSITESGENERALCORROSIONISWIDESPREADANDISCAUSED,USUALLY,BYIMPURITIESINTHEMETALORCHARACTERISTICSOFTHEMETALORITSENVIRONMENTTHATRESULTSINANOVERALLFOULINGOFTHEMETALSURFACELOCALIZEDCORROSIONRESULTS,冷凝水處理周期的增加從2到6。然而,只有一個進一步減少5的周期是增加在6至10,只有進一步減少2作為周期增加到20。因此,在大多數應用程序,循環冷卻塔的濃度維持在5到10之間的正如所指出的那樣,大規模集成電路,肢體重復性勞損癥,和/或PSI和沉積抑制劑添加為必要。而低損耗更多的水的循環和處理化學品、化學物質的數量需要治療往往走下來與周期和510周期通常代表一個好的平衡點。畢業設計論文代做平臺580畢業設計網是專業代做團隊也有大量畢業設計成品提供參考WWWBYSJ580COMQQ3449649974降低硬度通過排污或甚至被水軟化預處理可能不會消除潛在的沉積在冷凝器水系統。在這些情況下,化學治療,即。,添加到水系統沉積抑制劑,就成為必要當溶解鹽沉淀和沉積在金屬表面潤濕的冷凝器水系統,形成一個晶體生長,就附著在金屬表面,因為它出來的解決方案。最常用的阻垢劑用于冷凝器水系統是POSPHONATES,有機磷酸化合物,比如HEDP,函數通過吸附在晶體上他們,阻止他們形成粘附金屬。因此,這些晶體沉淀出的解決方案,通常在塔盆地132腐蝕控制1321電化學腐蝕金屬腐蝕發生電化腐蝕的結果在一個帶負電荷的“極”或網站上的金屬表面。兩個陽極,帶負電荷的網站,和陰極,帶正電的網站,可以創建在金屬由于雜質在金屬、局部應力,金屬晶粒尺寸或成分差異,甚至金屬表面上的劃痕。由于不同的費用,有一個電位陽極和陰極之間,電流從陽極電子流到陰極,利用周圍的水作為導體或電解質,如圖132對鋼鐵、陽極反應是鐵放出兩個自由電子,成為帶正電。這個帶正電的鐵然后結合兩個羥基自由基從水中形成氫氧化亞鐵,進一步與水相結合,從氫氧化鐵,當脫水,是鐵的氧化物或生銹。在陰極,釋放出的電子在陽極與水結合產生羥基自由基反應的平衡腐蝕,然后是金屬損耗它的字面意思是“溶解。“腐蝕可以表現出兩個特點取決于底層的陽極和陰極的原因網站。一般腐蝕是廣泛和引起,通常,雜質在金屬或特征的金屬或其環境,形成一個整體的金屬表面污垢。局部腐蝕的結果,主要是,從劃痕,壓力,或局部環境和最常見的原因為“金屬失效。FIGURE132TYPICALSTEELCORROSIONCHEMISTRYCOURTESYOFBETZDEARBORN,INC,TREVOSE,PENNSYLVANIAMOSTLY,FROMSCRATCHES,STRESS,ORLOCALIZEDENVIRONMENTANDTHEMOSTCOMMONREASONFOR“METALFAILURE”IFDISSIMILARMETALSWITHDIFFERENTELECTRICALPOTENTIALSAREUSEDINACONDENSERWATERSYSTEM,GALVANICCORROSIONISENHANCEDANDTHEMETALSSIMPLYCORRODEFASTER,PARTICULARLYATANDNEARTHEPOINTSOFCONTACTBETWEENTHEMETALSTHEFIRSTSTEPINCORROSIONCONTROLISTOMINIMIZETHECONTACTBETWEENWATERANDMILDSTEELMATERIALSALLPRIMARYWETTEDSURFACESWETDECKSFORINDUCEDDRAFTTOWERSANDBASINSSHOULDBECONSTRUCTEDOFSTAINLESSSTEELTHISTYPICALLYINCREASESTOWERCOSTSBYONLYABOUT15ANDISGENERALLYAWORTHWHILEINVESTMENTUSEPLASTICSORFIBERGLASSFORTHETOWERCASING,WETDECKCOVERS,INTAKELOUVERS,DRIFTELIMINATORS,ANDFILLFINALLY,IFMILDSTEELISUSEDFORTHETOWERSTRUCTURALFRAME,ITSHOULDBEGALVANIZEDAND,ASDISCUSSEDINSEC1322,COATEDWITHANEPOXYORPOLYMERFINALPROTECTIVECOATINGHOWEVER,THEPIPINGINMOSTCONDENSERWATERSYSTEMSWILLBESTEELANDMUSTBEPROTECTEDFROMCORROSIONTHISISACCOMPLISHEDBYUSINGONEORMORETREATMENTPROGRAMS,ASFOLLOWSPASSIVATINGANODICINHIBITORSTHESECHEMICALSFORMAPROTECTIVEOXIDEFILMONTHEMETALSURFACEWHICHISNOTONLYTOUGH,BUT,WHENDAMAGED,QUICKLYREPAIRSITSELFTYPICALCHEMICALSTHATACTASPASSIVATINGINHIBITORSINCLUDEMOLYBDATE,POLYPHOSPHATES,ANDORTHOPHOSPHATETHESECHEMICALSAREOXIDIZERSTHATPROMOTEPASSIVATIONBYINCREASINGTHEELECTRICALPOTENTIALOFIRONTHEDRAWBACKTOTHEUSEOFMOLYBDATEISITSEXPENSE,ANDITISUSEDONLYWHENBLOWDOWNLEVELSAREKEPTASLOWAS圖132。典型的鋼腐蝕化學。由BETZDEARBORN,INC,賓夕法尼亞TREVOSE。如果不同的金屬與不同的電勢是用于冷凝器水系統、電化學腐蝕是增強和金屬腐蝕速度,特別是在簡單和點附近S的金屬之間的聯系。腐蝕控制的第一步是最小化之間的接觸水和軟鋼材料。所有主濕表面濕甲板對誘導通風塔和盆地應該是采用不銹鋼。這通常會增加塔的成本只有約15,通常是一個有價值的投資。用塑料或玻璃纖維為塔套管、濕甲板封面,攝入量百葉窗,芯材料,并填寫。最后,如果低碳鋼是用于塔式結構框架,它應該是鍍鋅和所秒。1322,涂有環氧樹脂或聚合物最終保護涂層。然而,在大多數冷凝器水管道系統將鋼和必須免受腐蝕。這是通過使用一個或多個處理程序,如下所示鈍化陽極抑制劑這些化學物質形成保護性氧化膜在金屬表面不僅是艱難的,但是,當損壞,迅速修復本身。典型的化學物質作為鈍化抑制劑包括鉬酸鹽、聚磷酸鹽、正磷酸鹽。這些化學物質是氧化劑,促進鈍化通過增加電氣潛在的鐵。的缺點使用鉬酸鹽是它的費用,它只用在排污水平盡可能。OTHOPHOSPHATES不應該用于冷凝器水系統包含不銹鋼,因為它將使金屬脆性隨時間變化而變化。POSSIBLEOTHOPHOSPHATESSHOULDNOTBEUSEDINCONDENSERWATERSYSTEMSCONTAININGSTAINLESSSTEELSINCEITWILLMAKETHEMETALBRITTLEOVERTIMEPRECIPITATINGINHIBITORSATCATHODICSITES,THELOCALIZEDPHATTHESITEISINCREASEDDUETOTHEHIGHERCONCENTRATIONOFHYDROXIDEIONSTHATAREBEINGPRODUCEDPRECIPITATINGINHIBITORSFORMCOMPLEXESTHATAREINSOLUBLEATTHEHIGHERPHAND,THUS,PRECIPITATEOUTOFTHEWATERZINCISAGOODPRECIPITATINGINHIBITORMOLYBDATEWILLALSOACTASAPRECIPITATINGINHIBITORAND,THUS,CANSERVEASACORROSIONINHIBITORUSINGTWOMECHANISMSADSORPTIONINHIBITORSTHESEAREORGANICCOMPOUNDSCONTAININGNITROGEN,SUCHASAMINES,ORSULFURORHYDROXYLGROUPSDUETOTHESHAPE,SIZE,ORIENTATION,ANDELECTRICALCHARGEOFTHEMOLECULE,THEYWILLATTACHTOTHESURFACEOFTHEMETAL,PREVENTINGCORROSIONTHEIRDRAWBACKISTHATTHEYFORMTHICK,OILYSURFACEFILMSTHATREDUCEHEATTRANSFERCAPABILITYEACHPROGRAMISDESIGNEDFORPARTICULARCONDENSERWATERPHRANGEANDWATERCHEMISTRY,ASSUMMARIZEDINTABLE134TOPROTECTCOPPERINHEATEXCHANGERTUBESANDPIPINGFROMCORROSION,AROMATICTRIAZOLES,SUCHASBENZOTRIZOLEBZTANDTOLYLTRIAZONETTA,AREUSEDINMOSTCONDENSERWATERTREATMENTSYSTEMSTHESECOMPOUNDSBONDWITHTHECUPROUSOXIDEONTHEMETALSURFACEANDPROTECTIT1322WHITERUSTSINCETHELATE1970S,THEREHASBEENASIGNIFICANTINCREASEINTHEUSEOFGALVANIZEDSTEELCOOLINGTOWERS,PARTICULARLYINTHEHVACMARKETWITHTHEADVENTOFNEWCOOLINGTOWERWATERTREATMENTPOLYMERSANDCORROSIONINHIBITORS,MOSTCONDENSERWATERTREATMENTPROGRAMSNOWUTILIZELITTLEORNOACIDADDITION,ANDOPERATINGPHLEVELSHAVEINCREASEDFROM6575TOASHIGHAS95WITHTHENEWALKALINEPOLYMERAPPROACHASTHETECHNOLOGYOFTHEWATERTREATMENTINDUSTRYHASCHANGED,THECORROSIONOFGALVANIZEDSTEELHASNOWBECOMEAMAJORCONCERNTHETERMWHITERUSTREFERSTOTHEPREMATURE,RAPIDLOSSOFGALVANIZEDCOATINGONCOOLINGTOWERMETALSURFACESWHITERUSTISEVIDENCEDBYAWHITE,WAXY,NONPROTECTIVEZINCCORROSIONDEPOSITONWETTEDGALVANIZEDSURFACESTHISRAPIDTABLE134WATERPHANDCHEMISTRYFORCORROSIONPROGRAMSPROGRAMWATERPHANDCHEMISTRYZINCMOLYBDATEORMOLYBDATE/ZINCORTHOPHOSPHATEORGANICADSORPTION758575957585,WITHAPHOSPHATEDEPOSITIONINHIBITOR7595,WITH300500PPMALKALINITY沉淀抑制劑在陰極的網站,在網站的本地化的PH值增加是因為更高濃度的氫氧化物離子,正在生產。沉淀形成不溶性復合物的抑制劑在PH值越高,因此,沉淀出水面。鋅是一種良好的沉淀劑。鉬酸鹽還作為沉淀劑,因此,可以作為緩蝕劑使用兩種機制。吸附抑制劑這些都是含氮的有機化合物,如胺類、或硫或羥基。由于形狀、大小、方向、電荷的分子,他們將附著在表面的金屬,防止腐蝕。他們的缺點是它們形成厚,油性表面膜,降低傳熱能力。每個項目是專為特定的冷凝器水PH值范圍和水化學、總結如表134。保護銅在熱交換器管和管道受到腐蝕,芳香族雜四唑,如BENZOTRIZOLEBZT和TOLYLTRIAZONETTA,用于大多數冷凝器水處理系統。這些化合物債券與氧化亞銅在金屬表面和保護它1322。白銹病自1970年代末以來,已經有一個顯著增加使用鍍鋅鋼冷卻塔,尤其是在暖通空調市場。隨著新冷卻塔水處理聚合物和腐蝕抑制劑,大多數冷凝器水處理項目現在利用很少或沒有酸加上和操作PH值從65增加到75高達95與新堿性聚合物的方法。隨著技術的水處理行業已經發生了改變,腐蝕的鍍鋅鋼已成為一個主要關注的問題。這個術語是指白銹病過早,迅速失去鍍鋅涂層冷卻塔的金屬表面。白銹,證明了一個白色,蠟質,NONPROTECTIVE鋅腐蝕押金濕鍍鋅表面。這種快速的損失導致腐蝕的鍍鋅鋼和底層,而不是塔系統,將持續2025年,設備將會大大縮短壽命。表134水的PH值和化學腐蝕項目材料水的PH值鋅鉬酸鹽或鉬酸鹽/鋅正磷酸鹽有機吸附758575957585,磷酸鹽沉積抑制劑7595,WITH300500PPM堿度THISRAPIDLOSSOFGALVANIZINGRESULTSINTHECORROSIONOFTHEUNDERLYINGSTEELAND,INSTEADOFTOWERSYSTEMSTHATWILLLAST2025YEARS,EQUIPMENTWILLHAVEDRASTICALLYSHORTENEDLIFESPANSMANYBELIEVETHATTHECHANGETOTHEDRYKETTLEMETHODOFGALVANIZING,WITHCONTINUOUSSHEETSTEELSEECHAP10,HASHADANEFFECTONTHEINCREASEDFORMATIONOFWHITERUSTINITIALRESEARCHHASSHOWNTHATTHELEVELSOFALUMINUMANDLEADINTHEGALVANIZINGHAVECHANGEDWITHTHEWETKETTLEMETHOD,LEADLEVELSWERE06010ANDALUMINUMLEVELSWERE0005LEVELSOFLEADHAVEDROPPEDTO005ANDLEVELSOFALUMINUMHAVEINCREASEDTO040SINCEGOINGTOTHECONTINUOUSSHEETGALVANIZINGTHISINCREASEINALUMINUMANDDECREASEINLEADISBELIEVEDTOHELPINCREASETHEBRIGHTNESSOFTHEMETALSURFACES,MAKINGABETTERLOOKINGPRODUCTTHEHIGHERALUMINUMPERCENTAGEISALSONECESSARYFORBETTERBONDINGOFTHEZINCCOATINGTOTHESTEELTHECOOLINGTOWERMANUFACTURERSDONOTBELIEVETHATCHANGESINTHEGALVANIZINGPROCESSORINTHELEADANDALUMINUMLEVELSDEPOSITEDARERESPONSIBLEFORTHEINCREASEOFWHITERUSTTHEINDUSTRYHASSTATEDTHATALUMINUMLEVELSHAVENOTCHANGEDANDTHATTHEGALVANIZEDCOATINGISACTUALLYMORETHANTWICEASTHICK235OZOFZINCPERFT2OFSTEELSHEETASTHEYWERE20YEARSAGOHOWEVER,ITCANBEDOCUMENTEDTHATCOOLINGWATERPROGRAMSOPERATEDWITHAPHRANGEOF8085FORMANYYEARSWITHOUTHAVINGWHITERUSTPROBLEMSITCANALSOBEDOCUMENTEDTHATNEWTOWERSADDEDTOEXISTINGSYSTEMS,USINGTHESAMEMAKEUPWATER,CHEMICALTREATMENT,ANDCONTROLSHAVEDEVELOPEDWHITERUST,WHILETHEORIGINALUNITSHAVENOTTHEREFORE,WHITERUSTDOESNOTAPPEARTOBEAWATERQUALITYAND/ORWATERTREATMENTPROBLEMSOWHILETHEARGUMENTCONTINUES,ANDBASEDONCURRENTINFORMATION,ITISWELLESTABLISHEDTHATWHITERUSTMAYFORMIFTHEFOLLOWINGCONDITIONSEXIST1THEGALVANIZEDCOATINGISNOTPROPERLY“PASSIVATED”WHENTHETOWERISPLACEDINSERVICEPASSIVATIONISAPROCESSTHATALLOWSTHEZINCCOATINGTODEVELOPANATURALNONPOROUSSURFACEOFBASICZINCCARBONATETHISCHEMICALBARRIERPREVENTSRAPIDCORROSIONOFTHEZINCCOATINGFROMTHEENVIRONMENT,ASWELLASFROMNORMALCOOLINGTOWEROPERATIONTHEBASICZINCCARBONATEBARRIERWILLFORMONGALVANIZEDSURFACESWITHIN8WEEKSOFTOWEROPERATIONWITHWATEROFNEUTRALPH6580,CALCIUMHARDNESSOF100300PPM,ANDALKALINITYOF100300PPM2CONDENSERWATERISMAINTAINEDATPHABOVE803HIGHCONDENSERWATERALKALINITYABOVE300PPM4LOWCONDENSERWATERCALCIUMHARDNESSLEVELBELOW100PPM5THELACKOFPHOSPHATEBASEDCORROSIONINHIBITORINTHECONDENSERWATERTREATMENTPROGRAMFORMOSTGALVANIZEDMETALHVACCOOLINGTOWERS,WHITERUSTWILLOCCURIFNOTPREVENTEDBYTHEFOLLOWINGSTEPS這種快速的損失導致腐蝕的鍍鋅鋼和底層,而不是塔系統,將持續2025年,設備將會大大縮短壽命許多人認為改變干鍋法的鍍鋅,連續鋼片參見第十章,已經沒有效果增加形成的白銹。初步研究表明,鋁和鉛的含量在鍍鋅已經改變了。與濕鍋法、鉛水平分別為06010和鋁含量0005。的鉛水平已降至005,鋁的含量增加到040自去連續板鍍鋅。這增加鋁和降低鉛被認為有助于提高金屬表面的亮度,使一個BETTERLOOKING產品。較高的鋁比例也必要更好的結合的鋅涂層的鋼。冷卻塔制造商不相信改變過程或主要的熱鍍鋅和鋁水平沉積負責增加的白銹。這個行業已經表示,鋁含量沒有改變,鍍鋅層實際上是兩倍厚235盎司每FT2鋅的鋼板,他們20年前。然而,它可以證明,冷卻水程序操作的PH值范圍的8085多年不用白銹病問題。它也可以證明,新塔添加到現有的系統,使用相同的補給水、化學治療和控制已經開發出白銹病,而原單位沒有。因此,白銹病似乎不是一個水質和/或水處理問題。因此,爭論仍在繼續,并根據當前的信息,它已經知道白銹病可能形式如果下列條件存在1。鍍鋅層是不恰當的“鈍化”當塔被放置在服務。鈍化是一個過程,使鋅涂層開發自然無孔的表面的堿式碳酸鋅。這個化學屏障阻止快速腐蝕的鍍鋅層從環境,以及從正常的冷卻塔操作。堿式碳酸鋅的屏障將形成在鍍鋅表面在8周內塔的操作與水中性PH6580、鈣硬度100300PPM,堿度的100300PPM。2。冷凝器水PH值維持在80以上。3。高冷凝器水堿度超過300PPM。4。低的冷凝器水鈣硬度級別低于100PPM。5。缺乏磷酸鹽緩蝕劑在冷凝器水處理程序。對于大多數鍍鋅金屬暖通空調冷卻塔、白銹將發生如果沒有阻止通過以下步驟1PROVIDEASECONDARYBARRIERCOATINGONALLWETTEDSURFACES,SUCHASEPOXYORPOLYMERFINISHFORANEWTOWERORCOALTARBITUMENONANEXISTINGTOWERANEVENBETTERAPPROACHISTOSPECIFYNEWTOWERSTOHAVEWETTEDSURFACES,SUCHASBASINSANDWETDECKS,TOBECONSTRUCTEDOFSTAINLESSSTEELTHISOPTIONISNORMALLYAVAILABLEFORONLYA1020COSTINCREASE2RUNTHECOOLINGWATERTREATMENTPROGRAMATAPHBETWEEN70AND80,WHICHMAYREQUIREPHCONTROL3MAKESURETHEGALVANIZEDTOWERISPROPERLYPASSIVATEDUPONSYSTEMSTARTUPWHEREWHITERUSTHASOCCURRED,THEMETALCANBE“REPASSIVATED”BYTREATINGTHESURFACEWITHA5SODIUMDICHROMATEIN01SULFURICACID,BRUSHINGWITHASTIFFWIREBRUSHFORATLEAST30SEC,THENRINSINGTHOROUGHLY4INCORPORATEAPHOSPHATEBASEDPRODUCTINTOTHEWATERTREATMENTPROGRAM,ALONGPROPERDISPERSANTS133BIOLOGICALFOULINGCONTROL1331BIOLOGICALFOULINGBIOLOGICALFOULINGRESULTSFROMBACTERIA,FUNGI,ZOOPLANKTON,ANDPHYTOPLANKTONORALGAEINTRODUCEDTHROUGHMAKEUPWATERORFILTEREDFROMTHEAIRPASSINGTHROUGHANHVACCOOLINGTOWER“FOULING”RESULTSWHENTHESEMICROORGANISMSGROWINOPENSYSTEMSRICHINOXYGENANAEROBICPROCESSANDFORMSLIMEONTHESURFACESOFTHETOWER,PIPING,ANDHEATTRANSFERSURFACESOFTHECONDENSERWATERSYSTEMSLIMEISANAGGREGATEOFBOTHBIOLOGICALANDNONBIOLOGICALMATERIALSTHEBIOLOGICALCOMPONENT,CALLEDTHEBIOFILM,CONSISTSOFMICROBIALCELLSANDTHEIRBYPRODUCTSTHENONBIOLOGICALCOMPONENTSCONSISTOFORGANICAND/ORINORGANICDEBRISINTHEWATERTHATHASBECOMEADSORBEDORIMBEDDEDINTHEBIOFILMLAYERTHEIMPACTOFBIOLOGICALFOULINGISTWOFOLDTHESLIMEACTSASANINSULATORANDREDUCESHEATTRANSFEREFFICIENCYINTHESYSTEM,ANDMICROBIALACTIVITYWITHINTHESLIMECANACCELERATECORROSIONBYCREATINGALOCALIZEDOXYGENRICHENVIRONMENTTHATACCELERATESOXIDATIONAVERYSPECIALCASEOFBIOLOGICALFOULINGINCOOLINGTOWERSISTHEBACTERIALEGIONELLA,WHICHISDISCUSSEDINSEC1332THENUMBERONEMETHODOFCONTROLLINGBIOLOGICALFOULINGISTOKEEPCOOLINGTOWERSCLEANATLEASTTWICEDURINGTHECOOLINGSEASON,THETOWERSHOULDBEDRAINED,SCRUBCLEANED,ANDALLOWEDTOFULLYDRYBEFOREREFILLINGTHEN,THEUSEOFCHEMICALTREATMENTWILLCOMPLETETHECONTROLCHORETHEREARETWOKINDSOFANTIMICROBIALCHEMICALSORBIOCIDESUSEDINCOOLINGTOWERWATERTREATMENTPROGRAMSTOCONTROLBIOLOGICALFOULINGOXIDIZINGANDNONOXIDIZING1。提供二次障礙涂層所有濕表面,如環氧樹脂或聚合物完成新塔或煤焦油瀝青在一個現有的塔。一個更好的方法是指定新塔有濕表面,如盆地和濕甲板,是采用不銹鋼。這個選項通常是用于只有1020的成本增加。2。運行冷卻水處理項目的PH值在70和80之間,這可能需要控制PH值。3。確保鍍鋅塔是在系統啟動正常鈍化。在白銹病發生時,金屬可以“REPASSIVATED”把表面5的重鉻酸鈉在01硫酸,刷牙用硬鋼絲刷至少30秒,然后徹底沖洗。4。合并一個磷酸鹽產品入水處理程序,以及適當的分散劑。133。生物污染控制1331。生物污染生物污染的結果從細菌、真菌、藻類浮游動物和浮游植物或介紹,通過添加水或過濾從空氣中穿過一個暖通空調冷卻塔。“污染”的結果當這些微生物生長在開放系統豐富的氧氣一個有氧過程,形成表面的粘液、管道、塔和傳熱表面冷凝器水系統。粘液是一個集合的兩個生物和NONBIOLOGICAL材料。生物成分,稱為生物膜,由微生物細胞及其副產品。那些非生物成分包括有機和/或無機水中的殘骸,已經成為吸附或嵌入到生物膜層。生物污染的影響是雙重的粘液作為絕緣體,降低傳熱效率的系統,和微生物活動在粘液可以加速腐蝕通過創建一個局部富氧環境,加速氧化。一個非常特殊的情況下生物污垢在冷卻塔是軍團菌的細菌,這是在美國證券交易委員會的討論。1332。一個方法的數量控制生物污染是保持冷卻塔清潔。至少兩次在冷卻的季節,塔應該耗盡,擦洗干凈,并允許完全干后再充填。然后,使用化學治療控制將完成家務。有兩種抗菌物質或殺菌劑用于冷卻塔水處理程序來控制生物污垢氧化和無氧化OXIDIZINGCHEMICALSINCLUDECHLORINE,BROMINE,ANDOZONETHATOXIDIZEORACCEPTELECTRONSFROMOTHERCHEMICALCOMPOUNDSUSEDASANTIMICROBIALS,THESECHEMICALSREACTDIRECTLYWITHTHEMICROBESANDDEGRADECELLULARSTRUCTUREAND/ORDEACTIVATEINTERNALENZYMESYSTEMSTHEYPENETRATETHECELLWALLANDDISRUPTTHECELLMETABOLICSYSTEMTO“KILL”ITWARNINGOXIDIZINGCHEMICALS,PARTICULARLYCHLORINE,CANREACTWITHSTEEL,INCLUDINGSTAINLESSSTEEL,ANDCAUSERAPIDCORROSIONTOPREVENTTHIS,CONCENTRATIONSOFTHESECHEMICALSMUSTBEKEPTLOW,IDEALLYTOLESSTHAN07PPMOXIDIZINGCHEMICALSMUSTBEINTRODUCEDINTOTHECONDENSERWATERSYSTEMINSUCHAWAYTOBERAPIDLYDISPERSEDTOPREVENTLOCALIZEDHIGHCONCENTRATIONSNONOXIDIZINGANTIMICROBIALSATTACKCELLSANDDAMAGETHECELLMEMBRANEORTHEBIOCHEMICALPRODUCTIONORUSEOFENERGYBYTHECELL,RESULTINGINITSDEATH,ANDARESOMETIMESREFERREDTOAS“SURFACEACTIVE”BIOCIDESTYPICALNONOXIDIZINGBIOCIDESINCLUDEISOTHIAZOLINES,GLUTERALDEHYDE,MBT,ANDPOLYQUATMICROBIALSINCONDENSERWATERSYSTEMSCANBECOMERESISTANTTOASINGLEMETHODOFATTACK,ORSOMEMICROBIALSMAYBEMOREORLESSIMMUNETOONETYPEOFATTACKTHEREFORE,ITISRECOMMENDEDTHATBOTHTYPESOFTREATMENTCHEMICALSBEUSEDOXIDIZINGANDNONOXIDIZING,EITHERBLENDEDTOGETHERORINALTERNATINGTREATMENTPATTERNS,ASINDICATEDBYPERIODICWATERTESTINGRESULTSTHEKEYTOASUCCESSFULBIOLOGICALTREATMENTPROGRAMISMAINTAININGADEQUATECHEMICALTREATMENTLEVELSATALLTIMESVIACONTINUOUSFEEDOFANTIMICROBIALSINTOTHECONDENSERWATERSYSTEM1332LEGIONELLACONTROLIN1976,34ATTENDEESATANAMERICALEGIONCONVENTIONINPHILADELPHIADIEDFROMAPNEUMONIALIKEDISEASETHATWASLATERTRACEDTOTHETHENUNKNOWNBACTERIATHATWENOWCALLLEGIONELLASINCETHISINITIALOUTBREAKWHICHWASREALLYPRECEDEDBYEARLIEREVENTSINAUSTIN,MNIN1957ANDWASHINGTON,DCIN1964,THERECOGNITIONOFLEGIONELLAASASERIOUSPROBLEMHASGROWNSIGNIFICANTLYACCORDINGTOTHEUSCENTERSFORDISEASECONTROLCDC,LEGIONNAIRESDISEASEINFECTSAPPROXIMATELY25,000PEOPLEINTHEUNITEDSTATESEACHYEARAND1015OFTHESECASESARETYPICALLYFATALTHISEQUATESTO30007000DEATHSATTRIBUTABLEEACHYEARTOLEGIONELLALEGIONELLAISABACTERIATHATISCOMMONINSURFACEWATERS,INCLUDINGLAKES,RIVERS,ETCTHEBACTERIASURVIVEROUTINEWATERTREATMENTANDLOWCONCENTRATIONSAREINTRODUCEDINTOMOSTPOTABLEWATERSUPPLIESLEGIONELLATHRIVESINWATERTEMPERATURESBETWEEN68AND1228F,WITHOPTIMALGROWTHOCCURRINGBETWEEN95AND1158FLOWPHANDHIGHLEVELSOFAQUATICGROWTHMICROBIOTA,AMOEBAE,ALGAL氧化化學物質包括氯、溴、和臭氧氧化或接受電子從其他化合物。作為抗菌劑,這些化學反應直接與微生物和降解細胞結構和/或關閉內部酶系統。他們穿透細胞壁,擾亂細胞代謝系統“殺