Heraeus Nitro Technologies - Katalysatoren

HeraeusNitro TechnologiesW. C. Heraeus

Heraeus Nitro Technologies LocationsLocationsHeraeus Nitro Technologies is abusiness unit of W C. Heraeus,the largest company in the HeraeusGroup. Heraeus Nitro Technologiesis deeply rooted in the history ofthe company as well as in today’soperations.It draws heavily on the expertise,manufacturing and researchresources, logistics and managementcompetence of the whole group.Manufacturing facilities are locatedin Europe, the United States, CentralAsia and the Far East with salesoffices in all major markets.Heraeus Nitro Technologies focusesits activities on providing productsand services for industrial ammoniaoxidation and hydrogen cyanideproduction. Groundbreaking innovations,technical and commercialcompetence, continuous improvementand the use of the most efficientproduction techniques make HeraeusNitro Technologies the worldwidetechnology and cost leader in itsbusiness area.W. C. Heraeus GmbH – HeadquartersHanau / GermanyHeraeus Metal Processing Inc., USARavindra Heraeus Private Ltd., IndiaHeraeus Materials Technology Shanghai Ltd.,P. R. China2

Catalyst GauzesHeraeus Nitro Technologies looksback on decades of experience incatalyst gauze manufacture. This longterm experience and the focus on thescience of precious metals ensuresthat the materials used for the manufactureof catalyst gauzes fulfil themost stringent standards in respectto their quality and purity. Over yearsof close monitoring of gauze performance,specific elements and substanceswhich adversely influenceeither the catalytic activity or mechanicalstability of the gauzes have beenidentified. Based on this experience,dedicated procedures have beenput in place at Heraeus Nitro Technologieswhich guarantee an excellentperformance of the gauzes.Heraeus Nitro Technologies maintainsa dedicated and segregatedstock of material for catalyst gauzemanufactureThe most modern material analysistechniques are used to control thematerial composition and level ofimpuritiesAll substances and compoundswith potentially negative influenceon catalytic activity are eliminatedfrom the manufacturing processAll gauzes are activated bya dedicated procedure in orderto ensure immediate light-offand rapid surface restructuringBy courtesy of Krupp Uhde, Dortmund, GermanyHeraeus Nitro Technologies not onlysupplies catalyst gauzes but alsoadvises customers on the best catalystconfiguration, alloy and structure.Using computer programs, optimizedcatalyst systems can be proposedto suit individual process parameters:By courtesy of Krupp Uhde, Dortmund, GermanyCatalyst gauzes for the oxidationof ammonia to nitrogen oxide3

Warp KnittingKnittingWarp knitted structureMore than a decade ago, Heraeusfirst developed and introduced a newproduction technique for catalystgauzes: warp knitting. This patentedproduction technique proved sosuccessful that soon the majority ofcatalyst gauzes in use throughout theworld are now manufactured usingthis technique. The traditional wovencatalyst gauzes have almost entirelybeen replaced by knitted products.to their inherent features:high mechanical strengthand form stability“self repairing” behaviourlow pressure drophigh surface arealow platinum lossesminimal rate of rhodiumoxide formationhigh conversion rate and selectivitylong operating cyclesThe choice of the warp knitting techniquewas made by Heraeus afterextensive comparative testing ofseveral different gauze structuresproduced with varying productiontechniques supported by mathematicalmodelling and simulation of thereaction processes. The warp knittedgauze proved best due to its outstandingperformance under industrialoperating conditions and becauseof the versatility of the warp knittingproduction technique itself.The Heraeus Nitro Technologies warpknitted catalyst gauzes are uniquelywell suited for catalyst reactions dueThe versatility of the warp knittingtechnique enables the manufactureof gauzes with:a large selection of gauze structuresa large selectionof specific catalyst weightsa wide range of gauze diametersa wide range of wire diametersa multitude of alloy specificationsfast productionand short delivery timesHeraeus Nitro Technologies continuesto offer woven products for the fewremaining customers wishing to usethis technology.4

FTCFTCand FTCplusand FTCplusFTC, Functional Total Control, is acompletely new concept for the catalyticoxidation of ammonia which hasbeen available since 1996 solely fromHeraeus Nitro Technologies.Using computer models, a fully integratedcatalytic package is designedspecifically for each reactor. FTC isdesigned to reduce total productioncosts: the cost savings are primarilyachieved by reducing precious metallosses and reducing the precious metalweight of the installed catalyst. FTCdoes away with the requirement ofcatchment systems to be installed inthe reactor.To accomplish this, FTC systemsutilise specially developed, complexalloys which enable the total weightof precious metals required to be substantiallyreduced. When comparedto conventional catalyst systems, costreductions of up to 35% per tonneof nitric acid produced have beenachieved in numerous industrial applications.This result has been achievedwithout sacrificing ammonia conversionefficiency or campaign length.On the contrary, ammonia conversionefficiencies are bench marked overeven extended campaigns. FTC issuitable for virtually all reactor types.Pd Wire: Active Pt is absorbedand diffuses to wire coreFTC Wire: Active Pt is absorbedand remains on wire surface1916:woven gauzes1966:woven gauzes +catchment gauzesFTCplus1992:warp knittedgauzes +catchment packHeraeus Nitro Technologies hassucceeded in developing a catalystsystem, FTCplus, which reducesthe nitrous oxide emission at source.Both FTC and FTCplus catalystsystems can be delivered in the formof individual gauze layers or pads ormounted on a stretcher.1996:FTC SystemsFTCplus has been commerciallyavailable since 2000. After installation,the emissions of nitrous oxidehave been reduced on averageby more than 30% over extendedcampaign lengths in many industrialapplications. FTC and FTCplusconsist of a number of metallic gauzelayers and can be installed in virtuallyany reactor. No changes to the reactoritself and no additional catalyst isrequired in order to operate FTCplus.Detailed documentation and installationinformation as well as on-siteinstallation support are available.2003:FTC-HR2000:FTCplus Systems5

SecondarySecundaryCatalystsCatalystsN 2 O Abatement Catalyst HR-SCThe greenhouse gas N 2 O is knownto have a global warming potential310 times higher than CO 2 . Annually,about 1.2 mio. tonnes of this gas areemitted by the nitric acid industry,which is equivalent to the CO 2emissions of 80 mio. passenger cars.The catalyst consists of materialscommonly used in NH 3 oxidationreactors. This ensures that no newmaterials are present endangeringthe product. The HR-SC systemis made of precious metal coatedceramic pellets which are filledinto steel cassettes designed tofit into the reactor.On one hand, the national environmentallegislation has become tighterin some countries after commencementof the Kyoto Protocol. On the otherhand, the Kyoto mechanisms allowthe industry to implement emissionreduction projects (CDM/JI) generatingcarbon credits. Industries emitting hugequantities of CO 2 to the atmosphereand plants where emission reductionsare only viable with very high investmenthave a definite demand forcarbon credits.Heraeus has developed a N 2 O abatementsystem (HR-SC) for nitric acidplants which enables the reduction ofemissions to any desired level.Depending on operating conditionsand the required level of emissionreduction the catalyst layer thicknessin medium pressure plants is typicallybetween 20 – 60 mm causing an additionalpressure drop of 1 to 40 mbar.The Heraeus N 2 O reduction catalysthas been subjected to an intensivedevelopment program in small scalereactors as well as in commercialinstallations with an output of morethan 1,000 tonnes of acid per day.Heraeus is marketing the HR-SCsystem on a lease basis, chargingthe customer monthly based on thequantity of acid produced (in tonnesof HNO 3 100 %). This businessmodel has major advantages:Cost transparencyfor the customerTechnical support andtrouble shooting are includedin the lease feeFree of charge disposalof the spent catalystat the Heraeus site6

SecondarySecundaryCatalystsCatalystsInstallation Modus of the N 2 O Abatement CatalystThe HR-SC is mounted directlybeneath the primary catalyst (gauzes).In most cases, there are no modificationsto be made prior to the installationof the Heraeus Secondary Catalyst.On rare occasions, the basket has tobe reinforced or a steel support gridhas to be lowered in order to createenough space for the system. Normally,some Raschig rings equivalent to thecatalyst layer will be removed.Chronology of HR-SC installation:1. Catalyst segments are delivered tothe customer packed in a woodenbox (usually one per reactor).2. The wooden box is lifted ontothe platform in the proximity ofthe reactor.4. Part of the Raschig rings need tobe removed: the layer of Raschigrings depends on the thicknessof the catalyst package.5. Raschig rings have to be levelledover the entire reactor area.6. A fine mesh Kanthal screen isinstalled in the reactor to protectthe surface of the Raschig rings.7. An alumina gasket is installedat the edge of the basket.8. The steel cassettes are installedin the reactor individually. Eachsegment is tagged, so it canbe identified in the installationsketch provided by Heraeus.9. The segments are connectedusing a special tool.Installation by our expertsPreparation of reactorSingle segment of secondary catalyst3. Heraeus will dispatch an applicationengineer, who will be present duringthe installation for assistance.Installation of the first HR-SC willbe carried out by Heraeus engineers.10. After having installedthe HR-SC system,the reactor can be fittedwith the catalyst gauzes.Completed installation7

SecondarySecundaryCatalystsCatalystsHR-SC – Summary of AdvantagesN 2 O abatement catalyst can beinstalled without major reactormodifications – no necessity forreactor redesignThe HR-SC system can achieveover 90 % reduction in N 2 Oemissions and thus earns largenumbers of carbon creditsHigh thermal stabilityNo mechanical abrasionof the preformsNo leaching of the catalyst layerThe system does not containany potentially hazardous materialsThere is no measurable effecton the oxidation efficiencyCatalyst stability has been provenover many months in industrialreactorsLow pressure dropCost optimization by combinationof FTCplus-gauze systems andHR-SCTypical medium pressure plantN2O in tail gas [ppmv]800600400200FTCplusN2O in tail gas [ppmv]120080040000StandardHR-SC010 20 30 40 50Catalyst layer thickness [mm]Gauzes onlyGauzes + 20 mm catalyst layer pack8

Corrugated Gauzes andCorrugatedProfiled PacksGauzesHeraeus offers a number of innovativesolutions based on the corrugatedtechnology. Corrugation was originallydeveloped for use in high pressurenitric acid plants in order to allow theinstallation of catchment or gettergauze technology while avoiding theproblems of massive pressure dropoccurring in the reactor. Heraeus hasfurther developed this basis technologyto extend its utilization into thefield of catalysis as well as modifyingit for application to packaged catalystsolutions.A major leap forward is the Heraeusdevelopment of corrugation and profilingtechnology for medium pressureapplications.By utilizing the Heraeus MP profilingtechniques, we can achieve thefollowing advantages for operatorsof reactors with diameters of 2 to7 metres:20 – 30 % reduction in specificload of N per unit areareduced volatilization of PGMsduring the production cycleconsiderably extended campaigndurationshigher ammonia conversionefficiencyeasy installation and removalEach system is individually computerdesigned for the reactor, the productionparameters and the specificcampaign. Please ask our engineers!Corrugated structureCorrugated structureCorrugation TechnologyGauzesCarriermaterialHigher surface areaLonger lifetimeHigher gas throughput9

WaferWaferCatalystsCatalystsA revolutionary catalytic product whichwill eventually replace conventionalgauze products is the high technologyWafer development by Heraeus.Greater active surface area, allowinghigher catalyst loading and reducingdirect precious metal installed andindirect precious metal inventories.Wafer is a highly robust, infinitelycustomisable catalyst package forammonia oxidation which is wire-free!The CAD structures available withthis technology and the flexible combinationof varied materials integratedinto the design allow plant managersto specify the ideal catalyst for eachcampaign. Wafer offers the followingadvantages over conventionalcatalysts:Much higher porosity,leading to faster reactionsand lower propensity forside and back reactions.Lower energy requirement.Built-in catalytic activation, nongeometricrandom forming processesresult in higher catalytic activity priorto ignition. Activity remains higherover extended periods.Robust and damage resistantpackage, through integrated functionalitya one or two piece solution isavailable for almost any application.The one or two piece solution alsoallows easy and quick installationand removal.Can be supplied in corrugatedand profiled forms, suitable for allatmospheric, medium and highpressure reactors. Please consultour engineers for your customizedsolutions.10

Gauze Delivery andDeliveryRecyclingand RecyclingStretcherHeraeus Nitro Technologies strives tomake gauze deliveries in a way whichis most convenient to its customers.Detailed documentation, installationguidelines, on-time delivery and on-siteinstallation support are all included inthe service.Gauzes can be supplied as individualsheets, as pads or using dedicatedpacking systems.A speciality of Heraeus Nitro Technologiesis the delivery of gauzes on theso-called Stretcher. The Stretcher isnot only a transport but also a gauzeinstallation system. The Stretcher isplaced over the reactor and the gauzesare released in such a way that thegauze pack is installed in one quick andeasy operation into the reactor. It isextremely well suited for reactors withdiameters of 2 m and above.Stretcher – the upper strip and board can beremoved and the catalyst opened out to lie flaton the burnerPrecious Metals RecoveryAn inherent feature of the ammoniaoxidation process is that the catalystgauzes lose weight. Platinum is lostprimarily in the form of volatile platinumoxide and to a lesser extent asparticles due to mechanical losses.Rhodium is lost in the form of rhodiumoxide which is not volatile and thelosses are primarily of a mechanicalnature. The rate of total losses makeup a linear function of the logarithm ofthe daily production rate per surfacearea of the reactor: this means thatthe higher the production rate per unitarea of reactor the higher is the rateof material losses.In today’s modern plant managementthe material lost from the catalystcannot be regarded as materialwhich is “lost forever”. Heraeus NitroTechnologies provides several wellestablished methods to recover nearlyninety per cent of the precious metalprimarily lost from the gauzes.11

Platinum RecoveryPlatinumFilters andRecoveryPlant CleaningFiltersPlatinum Recovery FiltersPlatinum recovery filters are airphase particulate filters which arepositioned downstream of the plant’sheat recovery train where gas temperaturesare well below 400° C.The filters not only collect particleswhich are transported by the reactiongases but also facilitate the condensationof the volatile platinum oxidefrom the gaseous phase. The filterscan be employed with or without acatchment system.Heraeus Nitro Technologies offers:Supply and re-packingof Platinum Recovery FiltersRefining of spent filtersRecovery rates between 30 – 50 %Low pressure dropTubes before plant cleaningPlant CleaningTubes after plant cleaningIn modern plants substantial amountsof precious metal catalyst are retainedin the heat recovery train and largequantities of precious metals can berecovered from spent heat exchangers.Also, there are various nondestructivecleaning methods whichenable the recovery of preciousmetals during normal plant turnaroundsor stoppages, while also improvingheat transfer and plant throughput.Heraeus Nitro Technologies throughour sub-contractor, 3D RecoveryEurope Ltd, provides:Non-destructive cleaning of plantsNon-destructive and destructivecleaning of plant componentsRecovery of precious metals fromcleaning residues, PGM containingdeposits and spent filtersIncreased plant performace12

Technical Services offeredTechnicalby HeraeusServicesInvestigation ServiceHeraeus Nitro Technologies routinelyuses a wide range of powerful investigationtechniques for product developmentand customer support. The mostcommonly used technique is ScanningElectron Microscopy (SEM) in conjunctionwith Energy Dispersive X-RayAnalysis (EDXA).With these methods the morphologyof the catalyst and the composition ofsurface contaminants can be quicklyand reliably investigated on small scalesamples. In more demanding situationsother techniques such as AugerElectron Spectrometry (AES) andSecondary Ion Mass Spectroscopy(SIMS) can be used for surfaceanalysis and sub-surface profiling.These methods are further supplementedby bulk material analysis techniquessuch as X-Ray Fluorescence Analysis(XRFA), Directly and InductivelyCoupled Plasma Optical EmissionSpectrometry (DCP and ICP-OES).With these modern investigationmethods Heraeus Nitro Technologiesconducts customer related studies onthe optimization of process parametersand on possible causes of operationaldisruptions. Catalytic poisons, carbonlayers or rhodium oxide deposits,which have been caused by anomaliesin temperature, pressure or gascomposition during service, as wellas bulk material contamination canbe indentified quickly and thus beavoided in future operation.Developed catalyst structureRhodium oxide needlesMassive Rh 2 0 3 formationMassive Fe contaminationScanning Auger spectometerMechanical damage (steam leak)13

Technical Services offeredTechnicalby HeraeusServicesAmmonia Conversion Efficiency MeasurementThe conversion rate of ammonia intonitric oxide is the decisive cost factorin the production of nitric oxide.Heraeus Nitro Technologies providesan ammonia conversion efficiencymeasurement service which enablesthe ammonia conversion rate to beprecisely determined for an individualreactor. The service includes consultations,on-site measurements andtraining of employees.100969093NO yield %8070600 75 150 225280 300Operating time daysTrouble ShootingHeraeus Nitro Technologies provides atrouble shooting service to customersin relation to the use of its productsand services.This service includes consultationsby phone or on-site and is aimed atsolving any problem which may occur.SEM / EDXA X-ray fluorescence analysis Optical investigation14

PreciousPreciousMetals ManagementMetals ManagementAs part of its comprehensive preciousmetals service Heraeus Nitro Technologiesoffers not only the physicalprecious metal cycle i. e. manufacture,processing, refining and engineering,but also a comprehensive preciousmetal management service.The service includes:24 hour world-wide trading andacquisition of precious metalsPrecious metal leasingPrecious metal handlingvia customer metal accountsLocal and qualitative precious metalswappingIn addition, the customers of HeraeusNitro Technologies have a direct linkto the specialists of the HeraeusMetal Trading Company who providecompetent expert information andadvice on the global precious metalmarkets.15

Worldwide Production LocationsChinaIndiaUSAHeraeus Materials TechnologyShanghai Ltd.1 Guang Zhong RoadZhuanqiao Town, Minhang DistrictShanghai 201108, P. R. ChinaPhone +86 (021) 64 42 62 66Fax +86 (021) 64 89 00 22E-mail: hmtsl@online.sh.cnwww.heraeus-hmts.comRavindra Heraeus Private Ltd.A – 196 (A), ´F ` RoadMewar Industrial Area,Madri, Udaipur 313 003, IndiaPhone +91 (294) 249 - 00 29, -20 27Fax +91 (294) 249 - 21 77, -18 25E-mail: info@ravindraheraeus.comwww.ravindraheraeus.comHeraeus Metal Processing, Inc.15524 Carmenita RoadSanta Fe Springs, CA 90760, USAPhone +1 (562) 921 74 64Fax +1 (562) 921 53 33E-mail: chuck.melges@heraeus.comE-mail: customerservice@heraeusca.comwww.heraeusca.comW. C. Heraeus GmbHEngineered Materials DivisionBusiness Unit Precious Metals TechnologyHeraeusstr. 12 – 1463450 Hanau, GermanyPhone + 49 (61 81) 35 51 04Fax + 49 (61 81) 35 35 33E-mail: traute.goetz@heraeus.comwww.wc-heraeus.com/precious-metals-technologyThe data given here are correct forApril 2006. We reserve the right to maketechnical alterations as necessary.Layout: 5TC, FriedbergPrinted in Germany3M 04.2006/N Reu