vsbk design option guidelines - skat · 2017-01-24 · vsbk design option guidelines \ vii a...

$: VSBK DESIGN OPTION Guidelines - Skat · 2017-01-24 · VSBK DeSIgN OPTION gUIDeLINeS \ vii a profitable VSBK business experienced professionals should be involved who assess the appropriateness$
VSBK DESIGN OPTION Guidelines

Authors : Heini Müller, Prabin Chhetri, Tobias Müller Editors : Karl Wehrle, Urs Hagnauer Proofreader : Madeleine Cannon Illustrations :PrabinChhetri,KesharJoshiLayoutandgraphics :KiirtistudioFirstedition :September2013Contact :SkatFoundation([email protected])

ISBN978-3-908156-49-9Copyrights©Skat,2013

ThisdocumentisnotintendedtobeaconstructionguideandentrepreneurswhoconsiderconstructingaVSBKarestronglyadvisedtocontactanexperiencedlocalorregionalVSBKexpert/consultant.

VSBK Design Option Guidelines

VSBKDeSIgNOPTIONgUIDeLINeS \ iii

Acknowledgements v

Background vi

Purpose of this documentation vi

Potentials and limits of this documentation vii

Feedback and up-grading of this documentation vii

Overview of VSBK viii

01 Foundation 1

02 Unloading mechanism support unit 3

03 Trolley guide 5

04 Brick corbelling 7

05 Brick support I-beams 9

06 Girder system 11

07 Arch/slab 13

08 Shaft 16

09 Cavity between shaft and shaft support structure 19

10 Shaft support wall 21

Contents

iv / VSBKDeSIgNOPTIONgUIDeLINeS

11 Kiln insulation boxes 23

12 Peep-hole pipes 25

13 Outer kiln wall structure 26

14 Working platform 29

15 Flue-ducts 31

16 Shaft top structure 33

17 Emission exhaust system 34

18 Flue gas dampers/valves 36

19 Shaft lid 38

20 Unloading bars 40

21 Unloading trolley 42

22 Brick unloading system 43

23 Access to the working platform 45

24 Roof 48

VSBKDeSIgNOPTIONgUIDeLINeS \ v

TheVerticalShaftBrickKiln(VSBK)developmentprocessdocumentationstartedduringitsappliedResearch&Developmentstagein1997andreachedafirstimportantmilestoneinthelegendary“BrickbyBrick-TheHerculeanTaskofCleaninguptheAsianBrickIndustry"in2008.Yettheactualconstructiondevelopmentprocesshasbeencontinuedsince.Inparticularthe“South–South”VSBKtechnologytransfertoSouthAfricaliftedtheVSBKtechnologysignificantly.AdditionalconstructionoptionshavebeenrealizedthatpromotetheVSBKtechnology as a globally recognized clean brickproductionsystem.However,theresultofthisprocesshasuntilnowneverbeensystematicallydocumentedandupdated.

SkatwouldliketoexpressitssincereappreciationtoSwissDevelopmentCooperation(SDC)foritscontinuedsupporttothedevelopmentoftheVSBKtechnologyanditsadaptiontospecificlocalcontexts.Withoutthispersistentcommitmentandtrust into the involved partners over a period ofmorethanadecadethedevelopmentoftheVSBKtechnologyasatechnicalandeconomicalviableenvironmentfriendlyalternativetotraditionalbrickproductionsystemswouldnothavebeenpossible.

SkatlikestoexpresssincerethankstothepilotingentrepreneursfromvariouscountrieswhomadetheVSBKtechnologylearninganddevelopmentpossible.OnlythroughthespiritofVSBKpioneers,whowereandarepreparedtopracticallytestnewapproachesandatthesametimetakesomerisks,theVSBKtechnologycouldbeexposedandtestedinthepracticalbusinessenvironment.

Skatisalsoverygratefultoallpartnerorganizationsandindividualprofessionalsfromvariouscountries,whoeachintheirownwaycontributedtowardsimportant“puzzles”inordertoup-gradeandperfecttheVSBKtechnology.TheymadeaSouth-Southtechnologytransferpossible.

Specialthankstoallthosewhocontributedtothedevelopmentandcompilationofthisdocumentation,inparticulartotheeuropeanexpertsinenergy&environment,kilnconstructionandceramics,Mr.MaxMüller,germany,Mr.HansSchmid,Switzerland,Mr.ekhardRimpel,germany,andMr.AloisMüller,Switzerland,aswellastoMr.UrsHagnauer,formerVSBKProjectManager,Nepal.

LastbutnotleastSkat,asthepartnerinchargeforthetechnologytransfertoSouthAfricawouldalsoliketoacknowledgetheVSBKProjectinSouthAfricawhichfinancedthedevelopmentandpublicationofthisdocumentaswellasourconsortiapartner,Swisscontact,whofacilitatedtheprojectimplementation.

Karl WehrleSkatConsultancy

Acknowledgements

vi / VSBKDeSIgNOPTIONgUIDeLINeS

ThispublicationispartoftheongoingeffortsoftheVSBKtechnologytransferprocessfromAsiatoSouthAfrica.ItispartofthetasksentrustedtoSkatinanoverallprocessofknowledgetransfer.ThefocusofthispublicationareboththemaindesignoptionsaswellasconstructionelementsoftheVerticalShaftBrickKiln.TheVSBKisthemostenergyefficientcoalfiredclaybrickproductiontechnology.eversinceSDCsupportedthesystematicVSBKtechnologytransferfromChinatoIndiain1996alotoflocalandinternationalVSBKworkingexperiencehasbeenaccumulated.Initsquesttocontributetocleanerclaybrickfiringsystems,andtherebytoacleanerenvironment,SDCalsosupportedtheVSBKtechnologytransfertoNepal,Vietnam,Afghanistan,Pakistanandsince2009toSouthAfrica.

IntheVSBKtechnologytransfertotheabovementionedcountries,excepttoVietnam,SkatConsultancyistheonlyinternationalorganisationthathasbeenaconstantpartnertoSDC’senvironmentalendeavoursince1996.ThisprofessionaltrustwascontinuallyacknowledgedbySkatConsultancywithitsprincipleworkingstrategy;tolocallyanchorthe

VSBKtechnologyandtherebybuildinglocalVSBKexpertswhileatthesametimecreatingandoverseeinganinternationalnetworkofexpertsandspecialiststosustaintheVSBKtechnologyaswellasitsconstantimprovements,documentationandinternationaldissemination,thereforemakingbestuseoftheinvestmentsmadebySDCandallotherpartners.

TheVSBKtechnologyisnotpatented.Sinceitscommercial,environmentalandsocialdevelopmentwasfinancedbySDCthistechnologyisconsideredan“opensource”technology.Theresultsof17yearsofVSBKdesign/constructionexperienceandknowledgefromallstagesofthevariousVSBKtechnologytransfershavebeencollectedandcompiledas“VSBK Design Option Guidelines”.

ThisdocumentationistheresultofprofessionalinvolvementofexperiencedeuropeanbrickkilnexpertswithglobalVSBKtechnologyexpertsandlocalpractitioners/entrepreneurs.Hencethisdocumentationconsidersboth;thecurrentstate-of-artbrickkilnknow-howateuropeanlevelaswellasgloballyappliedpracticalandtechnicaloptions.

However,latestadaptationstolocalcontextsbylocalexpertsinSouthAfricacouldnotbeincludedinthisdocumentsincetheyarebeingclaimedasintellectualproperty.Dependingoninteresttheymaybemadeavailablethroughaconsultancycontract.

Purpose of this documentation

ThroughtheSDCsupported“South–South"VSBKtechnologytransfertoSouthAfricanewthinking,newviews,newexpertsandtherebynewpotentialswereleadingtoadditionalconstructionoptions.AwarenessoftheuniqueenergyandenvironmentaladvantagesoftheVSBKtechnologyisrapidlybeingdisseminatedatagloballevel.Withthisdocument,expertsnotonlyinSouthAfrica but also at global level are enabled tomakeaneducateddecisionofhowtoadapttheVSBKtechnologyandthereforecontributetowardsanincreasedglobalVSBKdemandwhileatthesametimereducingthegreenhousegasemissionfromapollutingindustrialsector.

ThepurposeofthisdocumentationistoprovideageneraloverviewofdifferentVSBKconstructionoptionsandmakesitclearthatthereisno'One-size-fits-all'.For

Background

VSBKDeSIgNOPTIONgUIDeLINeS \ vii

aprofitableVSBKbusinessexperiencedprofessionalsshouldbeinvolvedwhoassesstheappropriatenessofagivenoptiontoagivensituationandthisdocumentaimstobeavaluableresourcefordecisionmakers.

Potentials and limits of this documentation

VSBKconstructionoptionsarealwayslinkedto,andwiththepurposeof,brickfiringanditsrelatedeconomics.AlthoughnumerousVSBKconstructionoptionsaregloballyimplementedbyvariousorganizations,expertsandentrepreneurs,theauthorsutilizedatwo-shaftVSBKdesignasreferenceandpurposefullylimitedthenumberofpossibleconstructionoptionsinthisdocumentinordertofocusonprovenpracticalandeconomicalpractices.Forindividualswithlimitedaccesstohightechsolutionsandhighup-frontfinancialinvestment,forwhateverreasons,currentindustrialized'stateoftheart'kilnconstructionmaterialsandtechniquesneedtobedownscaledintopracticalsolutions.Thisdocumentationnotonlyshowspracticaloptionsbutalsopresentspotentialfutureoptionsthatwillrequirelocalfine-tuningforviablefinaladaptiontothelocalcontext.ItwouldbewayoutofthescopeofthisdocumenttoexplainthedetailedaspectsoftheVSBKconstruction.Thisdocumenttries

toprovidebasicrationalesandexplanationswheredeemedessential.Itissometimesdifficulttopreciselyandappropriatelyprovidesketchesandexplanationstofullycomprehenddetailedconstructiondrawingsofdifferentoptions.Theycanbemadeavailable through a consultancy contract withanyoftheVSBKtechnologyserviceproviders.

ThisdocumentisnotintendedtobeaconstructionguideandentrepreneurswhoconsiderconstructingaVSBKarestronglyadvised to contact an experienced local or regionalVSBKexpert/consultant.

Feedback and up-grading of this documentation

AnyfeedbackandadditionalexperiencesregardingthevarioustechnicaloptionsismostwelcomedandcanbedirectedtoSkatFoundation([email protected]).SkatFoundation,alongwiththerespectiveexpertsandauthors,willaccordinglysecurefutureup-datestothisdocumentandmakethecollectedinformationavailabletoabroaderaudience,withreferencetothesourceofinformation.

viii / VSBKDeSIgNOPTIONgUIDeLINeS

01 Foundation

02 Unloading mechanism support unit

03 Trolley guide

04 Brick corbelling

05 Brick support I-beams

06 Girder system

07 Arch/slab

08 Shaft

09 Cavity between shaft and shaft support structure

10 Shaft support wall

11 Kiln insulation boxes

12 Peep-hole pipes

13 Outer kiln wall structure

14 Working platform

15 Flue ducts

16 Shaft top structure

17 Emission exhaust system

18 Flue gas dampers/valves

19 Shaft lid

20 Unloading bars

21 Unloading trolley

22 Brick unloading system

23 Access to the working platform

24 Roof

Overview of VSBK

03

20

0405

10

11

1619

17

01

2221

06

08

13

07

09

12

1518

14

24

23

02

VSBKDeSIgNOPTIONgUIDeLINeS \ 1

OPTION 1 : R.C.C. raft foundation(Suitablefornon-cohesivesoils)

Advantages

• equalloaddistributiononanytypeofnaturalgrownsoil

• employedworkingpersonnelcanworkonacleanandsafeplatform

• groundwaterpenetrationcanbeminimized

Disadvantages & Limits

• expensiveconstructionoptionduetotheuseofmassconcreteandreinforcementsteel

FunctionThefoundationisthepartoftheVSBKthatisindirectcontactwiththegroundandthroughwhichstructuralloads,includingtheweightofgreenbricks,coalstorageandmovementsarebeingtransferred.

Design principlesAuniversalfoundationdesignforalltypesofgroundistechnicallyandeconomicallynotfeasiblesincekeyparametersvaryaccordingtothelocalsituationandcontext.Therefore,thefoundationhastobeprofessionally designed, case by case and according tolocalcontexts.

AVSBKshouldneverbeconstructedonback-filledsoilorlandslide-proneareas.Specialdesignprecautionsmustbetakenforareashavingahighgroundwatertableorearthquakeexperience.

01 FOuNDATION

2 / VSBKDeSIgNOPTIONgUIDeLINeS

OPTION 3 : Pillar foundation(Suitableforbothcohesiveandnon-cohesivesoils)

Advantages

• SuitableoptionforaframestructureVSBKconstruction


• Generally requires horizontal concretetie-beamconnection

• Considerableamountsofshutteringmaterialisrequired

• Dependingontherequireddepthofthepillarsarelativelyexpensiveconstructionmethod

• Demandinginskill(preciseness)andsupervision

OPTION 2 : Brick footing(Suitableforcohesivesoils)

Advantages

• ABrickentrepreneurcanusehis/herownbricksforthisfoundationoptionandcanthereforeoptimizeexpenses


• Notapplicableforalltypesofgrounds and especially not an optimaloptionincasesofhighgroundwatertable

• Requiresgoodbrickquality

01 FOuNDATION


02 uNlOADING mEChANISm SuPPORT uNIT

OPTION 1 : m.S. I-beamsNote:M.S.I-beamsareinstalledperpendiculartothearchwallsinordertotransfertheloadofthebrickssettinginsidetheshafttothekilnfoundation.

Advantages

• economicaloptionduetotheutilisationofthearchwallfoundations

• Canaccommodatebothhydraulicandmanualunloadingmechanisms


• Foreignmaterialcouldfallintothepitstructurewhichcouldcreatecomplicationsforunloading procedures and are likelydifficulttoclean

• Inareasofhighwatertable,awatertightpitstructureshould be ensured in order to avoidwatercontactwiththeunloadingmechanism

FunctionTheunloadingmechanismsupportunitaccommodatestheheightofthehydraulicpistonorscrew,protectstheunloadingmechanismfrompotentiallybeingblockedduringoperationandbearstheloadoftheentirebricksettinginsidetheshaftduringunloadingprocedures.

Design principlesTheunloadingmechanismsupportunitmustbeartheentirebricksettingloadanditsunloadingsysteminsuchawaythatnostructuralsettings/damageswillhindertheunloadingoperation.

Therelatedpitshouldbeprotectedfromthenearbyfilledsoilandgroundwatersothattheunloadingmechanismcanmovefreely.


OPTION 2 : R.C.C. load bearing unitNote:Thisunitisseparatedfromthekilnstructure.Itbearstheentireloadofthebricksettinginsidetheshaftonitsownfoundation.

Advantages

• Pitstructureismaintenancefriendly


• Doesnotutilisethearchwallfoundationforsupport,itsconstructionrequiresheavyduty concrete and steel reinforcementandisthereforeconsidered expensive

• Onlyfeasibleongroundwithsufficientbearingcapacity

02 uNlOADING mEChANISm SuPPORT uNIT


OPTION 1 : Recessed mS C-channels

Advantages

• Lowwear&tearofthemasonrywallsduringunloading

• Correctpositioningoftrolleysbelowtheshaftisensured

• Trolleysandtheunloadedfiredbricksarepreventedfrombecomingwedgedbetweentheshaftsupportingwallsduring unloading procedures


• Wall corbellings are required near ground level, hence the wallconstructionbecomesmorelabourintensiveandtherefore costly

FunctionThetrolleyguideassistsincorrectlypositioningthetrolleyforunloadingproceduresand,whentheunloadingtrolleyiscorrectlypositioned,actsasasafety feature to prevent unevenly loaded trolleys fromtoppling.

Design principlesThetrolleyguidesaremadewithMSC-Channelsandareproperlyanchoredintothearchwalls.

03 TROllEy GuIDE


FuTuRE OPTION 1: Screwed-on guides

Advantages

• Lowconstructioncost• Simplifiedtrolleylockshencenomovableparts

• easymaintenance


• None

OPTION 2 : Protruded m.S. C-channels

Advantages

• Wallbrickcorbellingisnot required, hence the constructionbecomeslesstimeconsumingandthereforeless costly


• Chancesofinjuriesduringunloading procedures

03 TROllEy GuIDE


OPTION 1 : Two arch wall corbellings(1stand2nd ,oneachsideofthearchsupportingwalls)

Advantages

• Reducedriskoffiredbrickstumblingfromtheunloadingtrolley

• Lesswear&tearduetoM.S.C-Channeltrolleyguidesconstructedflushwiththearchwallsupportmasonry


• Archsidewallbrickcorbellingconstructionbecomestimeconsumingandthereforecostly

• Could hinder pulling out the trolleyduetothesmallgapof3cmbetweenthewallandthetrolleyduringemergencyunloading

FunctionThebrickcorbellingsincreasethearchwalldistanceforunhinderedunloadingofthefiredbricksandmovementofthetrolley

Design principlesThebrickcorbellingofagivenbrickcourseshouldideallynotexceed3cm.

Wallcorbellingscanbemade,butasamatteroffact,areoptionaldependingonthequalityofgreenbricks,firingandoperationpractices.

Sincethearchmasonrywallsdistanceandtheshaftsizehavedifferentmeasurementstherefractoryshaftcorbellingisadvisabletoavoiddamagesduringoperation.

04 BRICK CORBEllING


OPTION 2 : Corbelling at refractory brick shaft level

Advantages

• Easy to pull and push the trolley due to increased side space

• Constructionofthearchsidewallsislesstimeconsumingand therefore less costly

• Moreeconomicalbecausetheshaftsupportingcorbellinglayercanbeconstructedjustbeforethefirstrefractorybricklayeroftheshaft


• ProtrudedM.S.C-channeltrolleyguides(see3,option2)mustbefixedotherwisethetrolleyguidelockbecomestoolongwhichcouldbedifficultduring unloading

• Increasedriskoffiredbrickstumblingfromtheunloadingtrolley due to increased side space

04 BRICK CORBEllING


OPTION 1 : Brick support beam positioned for unloading 6 layers of bricks

Advantages

• Higher unloading capacity, also duringemergencysituations

• Reducedworkloadforpersonnel during regular operationsincelessunloadingproceduresareperformedforthesamenumberofbricksbeing unloaded

• Friendlyworkingenvironmentdue to less heat exposure

• Increasedcoolingdownratepossibility


• Thedimensionsoftheunloadingscrew/hydraulicpiston increases due to the increasedliftheight

FunctionThebricksupportI-beamistherestingplaceforunloadingbarsandthegirdersystemduringoperation.Betweenunloadingproceduresthebeamsupportstheentirebricksettingloadinsidetheshaftandtransfersittothearchsupportingwall.

Design principlesThebricksupportI-beamsmustbedesignedtocarrytheentirebricksettingwithintheshaft.

Thetemperatureattheunloadingplacecanattimesbeashighas400°C,whichneedstobeconsideredwhenestimatingtheI-beamdimensions.TheI-beamsshouldbecompletelystraight,neverevenslightlytwistedorbentandmustbepositionedparalleltoeachother.

05 BRICK SuPPORT I-BEAmS


OPTION 2 : Brick support I-beam positioned for unloading 4 layers of bricks (including a lower arch and reduced overall kiln height)

Advantages

• Duetothedecreasedliftheightthedimensionsoftheunloadingscrew/hydraulicpiston decreases

• Decreasesoverallconstructioncostsduetothereducedkilnheight


• Unloadingdifficultiesduringemergencysituations;hencean experienced & disciplined workingcrewisrequired

• Increasedworkloadforpersonnel during regular operationsincemoreunloading procedures are performedforthesamenumberofbricksbeingunloaded

• Increased heat exposure to workingpersonnel

05 BRICK SuPPORT I-BEAmS


OPTION 1 : Girder system with side locks

Advantages

• Noelectricityrequired• Lessupliftmovementofscrew/hydraulicpistonandthereforeeasierforworkingpersonnel


• Girder rail prone to bending duetoheatradiationandconstant load

• Increasesconstructiontimeduetofixingofalltherelatedmetalparts

FunctionAfterthetrolleyissecurelypositionedbeneaththefiredbricks,thegirdersystemfacilitatesthereleaseof the unloading bars and hence the load of the entirebricksettingistransferredtothetrolleyandtheunloadingsystem.

Design principlesThegirdersystemneedstobedesignedinawaythatitisabletocarrytheentirebrickload.Further,ithasbeensuredthatthereleasemechanismcannotbetriggeredaccidently(orunintentionally)andthebrickloadcanbetransferredontothetrolleywithoutpotentiallyinjuringworkingpersonnelwhenreleasingthesystem.

Whenahydraulicunloadingsystemisinplacethewholegirdersystemisnotrequired.

06 GIRDER SySTEm


OPTION 2 : Girder system with wedge locks(MSsquarerod/wedge)

Advantages

• Costeffective• Noelectricityrequired• Lessupliftmovementofscrew/hydraulicpistonandthereforeeasierforworkingpersonnel


• None

06 GIRDER SySTEm


OPTION 1 : Arch constructed with brick

Advantages

• Locallyavailablebrickscanbe used, therefore reduced constructioncosts


• Requiresanarchmould• Archconstructionwillincreasetheoverallkilnconstructiontime

FunctionThearch/slabstructureensuressafeaccesstounloadthefiredbricks.Italsodistributestheloadsofabovebuildstructuralandnon-structuralloadsintoitssupportingwalls.Further,airentering through this access opening is aiding boththecombustionandthebrickcoolingprocess.

Design principlesDifferentArchtypescanbedesigned.

Concretebeamsandarches;insituorprefabricated;areviablealternativestobrickarches.Afewofthemareshownasoptionsinthisdocument.

Beingarch,beamorslab,thefundamentaldesign criteria is that the structure is safely bearingtheloadplacedontopofit.Concretebased structures should not be exposed to temperaturesabove300°C.

07 ARCh/SlAB


OPTION 2 : In situ R.C.C. beam and slab

Advantages

• Savesonoverallnumberoffiredbricksforthekilnconstruction

• Noarchconstructionskillrequired


• Requiresshutteringmaterial• Willincreasetheoverallkilnconstructiontime

• Willlikelygetsomedamageincaseofhightemperatureexposure(e.g.brickmeltinginsidetheshaft)

FuTuRE OPTION 1 : Precast R.C.C. beams with 1 layer of front bricks attached as insulation and protection

Advantages

• Reducesoverallkilnconstructiontimeincasethepre-fabricationisdoneinfactories


• Requiresamechanicalliftingdevice to place it

• Forachievingeconomicaladvantagesalargenumberofshaftsneedtobeconstructed

07 ARCh/SlAB


FuTuRE OPTION 2 : Precast R.C.C. arch with 1 layer of front bricks attached

Advantages

• Reducesoverallkilnconstructiontimeincasethepre-fabricationisdoneinfactories



• Forachievingeconomicaladvantagesalargenumberofshaftsneedtobeconstructed

07 ARCh/SlAB


OPTION 1 : English bond refractory masonry without expansion joints

Advantages

• Uniformexpansionandcontractionproperties

• Uniformthermalmassproperties


• Specialmasonryskillsrequired• expansionwilldevelopuncontrolledmasonrycracks

FunctionTheshaftisthecoreelementofthekilnandhastoaccommodatethefiringofthebricksaspertheappropriatefirescheduleaswellastoprovideresistancetomechanicalwearandtearfromverticalmovementoftheloadedbricks.

Design principlesTheshaftdimensionmustbedesignedaccordingtothedrygreenbricksizeandmaximumproductioncapacity.

Further,thefollowingdesigncriteriashouldbeconsideredtoallowfortrouble-freebrickfiring:

• Heatresistanceoftheshaftwallingmaterialinthecentralfiringzoneupto1200°C

• Acidicemissionresistanceinthepre-heatingzone• Structuralexpansionproperties• Perfectverticality• Selfsupportingstructure

08 ShAFT


FuTuRE OPTION 1 : English bond refractory brick masonry with expansion joints

Advantages

• Uniformexpansionandcontractionproperties

• Uniformthermalmassproperties

• Controlledexpansionwillavoiduncontrolledmasonrycracks,hencelowermaintenance


• Specialmasonryskillsarerequiredandtheconstructionsystemistimeconsuming,therefore costly

• Requiresspecialbrickblocksorcuttings

• Specialcornersupportessentialtoensureexpansionatdefinedjoints

OPTION 2 : English bond refractory masonry; substituted with fired bricks in sections with temperatures below 500°C (pre-heating and cooling zone)

Advantages

• Mosteconomicaloptionundertheconditionthatthefiringzoneisalwaysmaintainedatthecentreoftheshaft


• Chancesofshaftdamagesifthefirepositionisnotproperlymaintainedatthecentreoftheshaft

• Firepositionadjustmentislimitedtorefractorymasonryarea

• Potentialdamagestofiredbrickmasonryinthepre-heatingzoneduetoacidicemissions

08 ShAFT

<500oC

>500oC

<500oC


FuTuRE OPTION 2 : Prefabricated fire resistance refractory concrete elementsNote:Thispossiblefutureoptionrequiresprofessionaloverallkilnconstructionplanningandpracticaldetaildesigns.

Advantages

• Reducedshaftconstructiontime

• Theshapeoftheelementcanbebothverticalorhorizontal



• Skilltomaintainthetotalverticalityoftheshaftisrequired

• Fire resistant refractory concrete is considered expensive

• Will develop uncontrolled cracksifnoexpansionjointsare provided

08 ShAFT


OPTION 1 : unfilled cavity (2-3 cm approx.)

Advantages

• Basicallynoexpenses(Howevertoensureanequalcavity size it is of advantage toplacealowcostthermocolboard.Thisthermocolboardwillmeltassoonasthekilnisinoperationandauniformcavitywillremain)


• Someheatlossduetoairmovement,hencereducedinsulationvalue

• Riskofmortarandothermaterialfillingupthecavityifnot carefully protected during construction

• Increased heat exposure at the shafttoparea

FunctionThe cavity is required to ensure structurally independentexpansionandcontractionoftheshaftstructure.

Design principlesThemainprinciplefordesigningthiscavitiyistoensurethestructuralintegrityoftheshaft.

Thetopandbottomofthiscavityshouldbeclosedwithaflexiblematerialafterthekilnisfullydriedoutinordertoavoidheatloss.

09CAVITy BETwEEN ShAFT AND ShAFT SuPPORT STRuCTuRE


FuTuRE OPTION 1 : Filled cavity(Stonewoolorglasswoolinsulationblanket/board)

Advantages

• Costbenefitfactorisgood


• Riskofsaggingwhenfixinginsulationblanketstoaverticalsurface

OPTION 2 : Filled cavitiy (Calciumsilicateboard)

Advantages

• Easy to install since they are availableasselfsupportingboards


• Damagepotentialifexposedtocontactwithwater

• Couldbeacostlyoptiondepending on selected materialquality

09CAVITy BETwEEN ShAFT AND ShAFT SuPPORT STRuCTuRE


OPTION 1 : English bond brick masonry in mud mortar

Advantages

• Lowconstructioncost• Provides reasonable stability forchimneysystem


• Chancesofwallsaggingduetomudmortarshrinkage

FunctionTheshaft-supportwallensurestheindependentworking(expansion/contraction)oftheshaft,reduceslateralpressureandactsasaninsulationlayer.Thechimneysareusuallyconstructedontopoftheshaftsupportingwall.

Design principlesTherearemanyshaftsupportwallconstructionsystemspossible,alldependingoneconomicalinsulatingbuildingmaterials.

Note:Usinga'K-value'calculatorforselectingthesizeofthemosteconomicalinsulationmaterial/structureisrecommended.

Note:Ifashaftisconstructedwithexpansionjoints,theshaftcornersmustbesupportedtoensurecorrectexpansiondirection.(see8,futureoption1)

10 ShAFT SuPPORT wAll


FuTuRE OPTION 1 : Vermiculite concreteNote:Vermiculitecanalsobeusedasinsulationmaterialbetweenbothstructures;theshaftandthesupportingwall.Note:Itisnecessarytoconsultprofessionalswhoareexperiencedinpracticalapplicationofvermiculiteconcretetechnologyforakilnconstruction.

Advantages

• Lowthermalconductivitymaterial,hencegoodinsulation

• Can be precast or constructed in-situ

• Doesnotrequireanyfurtherinsulationorstructure,exceptaprotectionlayer,e.gsteel

• Thekilnsizecanbereduced,hencematerialandlabourcostcan be reduced


• Isanexpensiveinsulationmaterial

• Vermiculiteconcretehasreduced load bearing capacity

FuTuRE OPTION 2 : Insulation bricks walls

Advantages

• Potentialofslimkilnstructureandcostreduction.


• Insulationbricksareexpensive• Insulationbrickshavereduced

load bearing capacity

10 ShAFT SuPPORT wAll


OPTION 1 : Filled with ungraded soil

Advantages

• Cheapest and easily available fillingmaterial


• Lowinsulationvalue,theheatlossisrelativelyhigh

• Difficulttoavoidwaterpenetrationduringconstruction

• Chancesofshaftbulgingincreaseswiththefrequencyofshutdownsduetorepeatedcompactingoffineparticles

FunctionKilninsulationboxesareconstructedtodistributetheloadofinsulationmaterialusedtominimizeenergylosses.Theyalsoproviderigiditytothekilnstructureanddefinethesizeoftheworkingplatform.

Design principlesTheboxdimensionsmustberelatedtotheinsulationmaterialvaluetobeusedandtherequiredworkingspaceandtypeofplatform.Thetopoftheinsulationboxes(platform)shouldideallybecoveredtoavoidheatloss.

Note:Fillingmaterialshouldbeasdryaspossible.

11 KIlN INSulATION BOxES


OPTION 2 : Filled with graded brick gravel

Advantages

• Inrelationtotheinsulationvalue it is a good and economicalfillingmaterial

• enhancedinsulationpropertiesduetocreationofmicro-pores

• Decreasedriskofshaftbulging


• Difficulttomaintainpropermaterialgradingduringfillingprocess

• Difficulttoavoidwaterpenetrationduringconstruction

11 KIlN INSulATION BOxES


OPTION 1 : m.S. pipes

Advantages

• Astraight-forward,practicalandeconomicalsystemforfireposition/temperaturemonitoring


• Potentialofexcessairenteringtheshaftifthepipesarenot properly sealed during operation

FunctionPeep-holepipesarenarrowopeningsinthekilnstructurewhichallowavisualand/ormechanicalfiretemperaturemonitoring.

Design principlesPeep-holesmustbedesignedtoallowvisualmonitoringofthefirepositionand/orinsertfiremonitoringequipment(thermocouples)fromtheoutsideofthekilnstructure.

Further,theyshouldbepositionedinawaythattheydonotbendundertheweightoftheinsulationfilling.

Theexactnessofthefirescheduleplottingincreaseswiththenumberofbuilt-inpeep-holepipes.

Therespectivebatchheightandthesoilshrinkagedefinesthepositionanddistanceofthepeep-holepipes.

12 PEEP-hOlE PIPES


OPTION 1 : load bearing brick masonry with buttresses

Advantages

• Can support above built structures(loadingplatform,roof,mechanicaltransportingdevicesetc.)andgreenbrickstorage

• Buttressessupportingtheaccesstoplatformcanreduceconstructioncosts


• Buttressesincreasetherequiredconstructionarea

FunctionTheouterkilnwallstructureencasestheinsulationfillingaroundtheshaftsupportingwallsandensuresstructuralrigidityandprotectionagainsttheelements.

Design principlesTheouterkilnwallstructuremustbedesignedsothatitcanprotecttheinsulationandtheshaftstructureagainstmechanicalimpact.

Note:Sufficientweepholesmustbeprovidedtoavoidkilnstructuredamagesduetowaterevaporationduringtheinitialfiring.Theseweepholeshouldbeclosedonlyafterthekilniscompletelydriedout.

13 OuTER KIlN wAll STRuCTuRE


OPTION 3 : metal

Advantages

• Can be prefabricated, hence reducesconstructiontime

• Slimmeststructurepossible• Masspre-fabricationpotential


• Metalcorrosionislikelythemainproblem,hencehighexpensesformaintenancework

• Separateplatformforbrickstorage required

• Requiresamechanicalliftingdevice to construct it

• High-valueinsulationrequired,hence expensive

• Relativelyunfavourableconstructioncarbonfootprintduetosteelrequirements

OPTION 2 : Concrete frame structure with in-filled brick masonry

Advantages

• Slimkilnstructurepossiblesincenobuttressesarerequired

• Overallconstructiontimereductionpossible


• Scaffoldingandformworkincreasetheconstructioncosts

• Additionalcostforreinforcementsteelandconcrete

• Relativelyunfavourableconstructioncarbonfootprintdue to concrete and steel requirements



FuTuRE OPTION 1 : load bearing brick masonry without buttresses

Advantages

• Potentialofslimkilnstructure.• Nobulkyinsulationboxes

required


• Separateplatformstructurerequiredformovementandstorage

• High-valueinsulationmaterialrequired, hence is considered expensive



OPTION 1 : Partial R.C.C. working platform on buttress

Advantages

• Requireslessreinforcementsteel due to support by masonrybuttresses

• Boxinsulationfillingmaterialcan be topped up


• Increased dust exposure potential

• Timeconsumingbecauseofshutteringwork,concretecuringtimeandde-shutteringwork

FunctionTheworkingplatformisconstructedforfreemovementofpersonnelandforstoragespace.

Design principlesTheworkingplatformdesignisbasedonbothloadbearing(buttress)structureorframestructureoptions.

However,theworkingplatformmustbeopen,ventilatedandprovideenoughspacesothatworkingpersonnelcanmovealongandloadgreenbricksintotheshaftwithouthindrancebyanystructureorequipment.

Note:IncaseofaslimVSBKstructure,e.g.metal,aseparateplatformstructureisrequired.

14 wORKING PlATFORm


OPTION 3 : Full R.C.C. working platform

Advantages

• Adds considerable rigidity to thekilnstructure

• Mechanicalgreenbricktransportationpossible

• Lowdustworkingenvironmentachievable

• Decreasedheatlossatplatformlevel


• Highconstructioncost• Duetothesettlingoftheboxinsulationfillingmaterialagapiscreatedinbetweentheinsulationfillandtheplatform

• Addsweighttothefoundation

OPTION 2 : Partial R.C.C. working platform on cantilever

Advantages

• Boxinsulationfillingmaterialcan be topped up


• Increasedreinforcementsteelandconcreterequirement,henceanexpensiveoption

• Timeconsumingbecauseofshutteringrequirement,concretecuringtimeandde-shutteringwork

• Increased dust exposure potential

14 wORKING PlATFORm


OPTION 1 : lower and upper flue-duct system constructed with refractory/fired bricks

Advantages

• Simplecleaningsystempossible

• Bestsuitedfornaturaldraughtsystem

• Costsavingspotentialifconstructedwithfiredbricks


• Theflueductsystemistheweakestpartoftheshaft,henceperiodicalmaintenanceis required

• Timeconsumingbrickcuttingworkduringconstruction

FunctionTheflue-ductsarethelowersectionoftheshaftemissionexhaustsystemwhichsystematicallychannelsthefluegasesintothechimneys.

Design principlesTheflueductsmustbedesignedtofunctioninawaythatallfluegassesarepassingthroughtheexhaustgassystem(naturalandforceddraughtsystem)withoutposinghealthhazardstoworkingpersonnel.Furtheritmustbeensuredthattheleastamountofexcessaircanenterthesystematthetopoftheupperflueductsduringunloading.

Theflueductsystemshouldbeconstructedwithacid-resistantmaterialssinceacidicgasesarereleasedduringthefiringprocess.

15 FluE-DuCTS


FuTuRE OPTION 1 : lower and upper flue-duct system constructed with refractory castables

Advantages

• Reducedconstructiontime• Bestsuitedforforceddraughtsystem

• Calibrationofindividualflueopenings possible

• economicviabilityincreaseswithnumbers


• Limitedtocountrieswithfireresistantconcretecastingexperience

15 FluE-DuCTS


OPTION 1 : R.C.C. shaft top anchored on the shaft supporting wall

Advantages

• Allowsverticalexpansionmovementoftherefractoryshaft

• Reducedshaftbulgingprobability


• None

FunctionTheshafttopprotectstheflueductsystemfrommechanicalandliveloadimpacts.Furtheritprovides a base for the lid cover and usually also for naturaldraughtchimneys.

Design principlesTheshafttopstructureshouldnotdisturbaverticalexpansionoftherefractoryshaft.

Itshouldbedesignedinsuchawaythatadditionalfeatureslikeflueductguides,lid-coverbaseandchimneyscanbesecurelyfixed.

Theexpansiongapmustbesealedwithflexiblematerialtoavoidheatlossafterthekilnisfullydriedout.

16 ShAFT TOP STRuCTuRE


OPTION 1 : Natural draught with flue ducts

Advantages

• Noelectricityrequired,henceaneconomicaloption

• Canbeconstructedwithmaterialotherthanmetal,i.e.firedbricks


• Draughtcanvarywithweatherconditions

• Difficulttoerectandtieupthechimneys,especiallyinhighwindproneareas

• Highwearandtearofmetalpartsduetocorrosionfromacidicemissions

FunctionTheemissionexhaustsystemistoprovidethedraftforproperfirepositioningaswellastodischargeexhaustgasesatasafeheight.

Design principlesTheemissionexhaustsystemmustbedesignedbyrespectiveexperts.

17 EmISSION ExhAuST SySTEm


FuTuRE OPTION 1 : Natural draught without flue ductsNote:Thissystemispreferredformultipleshafts.

Advantages

• elongatedfiringcurve• Uniformdraught• User friendly draught control• OneShaft-onechimney• Duringloading,emissionscan

be extracted separately• Inbuiltshaftlid,hencereduced

health hazard


• Anticorrosivematerialrequired for the hood

• Potentialofincreasedhoodsystemmaintenance

OPTION 2 : Forced draught with flue ducts

Advantages

• Uniformdraught,hencebetterfirepositioncontrol

• Onechimneycanbeusedformultipleshafts

• Brickqualityislikelytobemoreuniform


• Requires electricity, including a back-upsystem

• exhaustgastemperaturesmustbemaintainedtoavoidcorrosionofmetalparts

• Increasedmaintenancecosts

17 EmISSION ExhAuST SySTEm


OPTION 1 : m.S. sheet flat dampers

Advantages

• Areaneconomicaloption• User friendly to operate and

repair


• Probability of excess air entering

• Highcorrosionpotential

FunctionFluegasdampers/valvesregulatetheairflowwithinthesystem,thereforesteeringtheappropriatefirescheduleandensuringacleanworkingenvironmentwhileloadingthebricks.

Design principlesTheupperandlowerflueductsystemrequirestwoindependentvalves/damperseach,hence4valves/dampersarerequiredpershaft.

Valvesanddampersshouldbedesignedsothatleastamountofflue-gassescanpasswhentheyarecompletelyshut.

Damperslotsmustbeconstructedsothatnoexcessaircanenterintotheemissionexhaustsystem.

18 FluE GAS DAmPERS/VAlVES


OPTION 2 : m.S. sheet butterfly dampers

Advantages

• Areaneconomicaloption• User friendly to operate• Reduced probability of excess

air


• Highcorrosionpotential• Replacementonlypossibleduringshaftclosure,henceexpensive

18 FluE GAS DAmPERS/VAlVES

OPTION 3 : Valves for forced draught system

Advantages

• easiertocontroltheairflow• Airflowmetergaugecanbe

installed


• expensiveairflowmanagementsystem

• Highcorrosionpotentialifgreenbrickswith>1%moisturecontentareloaded

• Potentialexcessairproblemsifgapbetweenrefractoryshaft(flueductchannelopening)andvalvemouthisnotsealed


OPTION 1 : m.S. sheet lid/elements

Advantages

• Isaneconomicaloption


• Highcorrosionpotential

FunctionTheshaftlidsupportstheefficiencyofthecountercurrentairflowprinciple(energyefficiency)andensuresacleanworkingandgeneralenvironmentonaVSBK.

Design principlesShaftlidshouldbedesigneduser-friendlyaswellaslightweight,fireandpreferablycorrosionresistantmaterials.

19 ShAFT lID


OPTION 2 : Stainless steel sheet

Advantages

• Lowercorrosionpotential


• expensiveoption

19 ShAFT lID


FunctionTheunloadingbarssupportthebricksettinginsidetheshaftduringregularoperationandtransferthebricksettingloadtothebricksupportI-beams.

Design principlesAnunloadingbarshouldbedesignedlightweight,smallincrosssectionandmustbeabletoresisthighheatstressesunderconstantloadofapprox.4tons.

Note:Unloadingbarsaretobeconsideredoperationwear-and-tearmaterial.

20 uNlOADING BARS

OPTION 1 : m.S. square bars

Advantages

• LighterthanM.S.I-bars


• Highchanceofbrickbreakagesduetoreducedflangewidth


OPTION 3 : Reinforced m.S. square bars

Advantages

• Canbeusedforlargershaftdimension


• Highchanceofbrickbreakagesduetoreducedflangewidth

20 uNlOADING BARS

OPTION 2 : m.S. I-bars

Advantages

• StrongerthanM.S.squarebars• Lesschanceofbrickbreakagesduetobiggerflangewidth


• HeavierthanM.S.squarebarsand therefore rarely used for largershaftdimension


OPTION 1 : m.S. trolleys

Advantages

• Locally available and economicalfabrication

• Lightweighttrolleyscanbedesignedwhenusinga hydraulic unloading mechanism


• Trolleyweightincreaseswithlargershaftsize

FunctionTheunloadingtrolleyisusedtounloadthefiredbricksandtotransportthemtotheunloadingstations.

Design principlesThe unloading trolley should be designed in such a waythatitcanbearthebricksettingloadwithoutwarpingorbending.

Itmustbeaslightaspossiblebutstrongenoughtohandleemergencysituations.

21 uNlOADING TROllEy


OPTION 1 : Screw jack mechanismNote:Screwmustbefabricatedwithhighcarbonsteel.

Advantages

• Noelectricityrequired• Anelectromotorcanbe(retro)fittedtomechanicallyoperatethescrewjackmechanism


• Complexandtimeconsumingfabricationprocess

• Maintenance of nut is high as itismadeofcast-iron

• Accidentpronesystemandhardworkforpersonnel

FunctionThebrickunloadingsystemraisesandlowersthetrolleyandthebricksettingsinsidetheshaft.

Design principlesTheunloadingmechanismmustbecapableofbearingtheentirebricksettingloadinsidetheshaftandtoliftittothepointwherethesupportbarscanberetractedduringtheunloadingofthebrickswithoutthethreatofsuddenfailure.

Bothscrewjackandhydraulicunloadingsystemareingeneraldesignedtocarryandliftupto30tonsofweight(bricksandtrolley).

22 BRICK uNlOADING SySTEm


OPTION 2 : hydraulic mechanism

Advantages

• easytohandle,workingpersonnel are not exposed to hardworkandfallingcoal

• Nogirdersystemrequired,henceconstructiontimeandcost saving

• Fewerworkersrequired• Manualpowerpackcanbeappliedincaseofpowerfailure

• Trolleytrackcanbenarrowedand therefore trolley movementiseasier


• Requires electricity, including a back-upsystem

• Expensive lubricants required• Requires special dust protection

22 BRICK uNlOADING SySTEm


OPTION 1 : Ramp/staircase

Advantages

• Possiblythemosteconomicalconstructionoption

• Requires no electricity• Dependingongradientangle,mechanicalequipmentcanbeusedtocarrybricks


• Drudgeryworkforemployedpersonnel

• Highgreenbrickhandlingdamagepotential

FunctionIsthemeanstotransportgreenbricksandcoaluptotheworkingplatformlevelforanuninterruptedfiringprocess.

Design principlesThemaindesignparameteristotransportdrygreenbricksfromthegroundleveltotheworkingplatformlevelinthemosteconomicalway,ensuringthatthegreenbrickqualityisnotcompromised.

23 ACCESS TO ThE wORKING PlATFORm


OPTION 3 : lift

Advantages

• Reduced drudgery• Lessworkforcerequiredwhencomparedtomanualtransportationsystem

• Lowgreenbrickdamagepotential


• Requirespower(electricityorfuelgenerator)tooperate

OPTION 2 : Conveyor belt

Advantages

• Reduces drudgery• Lessworkforcerequiredwhencomparedtomanualtransportationsystem

• Veryefficientandswifttransportationsystem


• Highdrygreenbrickhandlingdamagepotential

• Highwearandtear,hencehighmaintenanceandrepaircostpotential


• Potentialoffallinggreenbricksincreasestheriskofinjury



OPTION 4 : Gantry

Advantages

• Reduced drudgery • Lessworkforcerequiredcomparedtoanyothersystem

• Lowgreenbrickdamagepotential

• Mechanized loading of green bricksintogantrycagepossible


• Highinitialinvestment• Onlyeconomicalforlargenumbersofshafts


• Requiresconsiderableplatformspace



OPTION 1 : high-end level(Corrugated/plainplasticroofingsheetsorP.V.C.corrugated/plainsheetsonslopedM.S.pipetrussesandpurlins)(Slopedconcreteorferro-cementroof)

Advantages

• Isresistanttodamagingemissions


• Is an expensive roof

FunctionTheroofprotectsthekilnstructureandworkingpersonnelfromtheelementssuchasrain,sunandwind.

Design principlesRoofshouldbedesignedaseconomicallyaspossiblewhileatthesametimeensuringthatthekilnremainsdry,greenbricksandworkingpersonnelareprotected.

Aroofmonitorisessentialtoensureproperventilationthatreducestheaccumulationofharmfulemissions.Theheightoftheroofshouldbeenoughforthefiremastertoworkefficientlyabovetheshafttopforloadingbricks.

24 ROOF


OPTION 3 : Budget level(Biodegradablematerials:Bamboomatsorclayroofingtilesontimberorbambootrussesandpurlins)

Advantages

• Isalowcostandfunctionalroofingoption


• Requiresregularreplacement/repairduetorelativeshortlifespanofmaterial

• Potentialofrainleakingexists

OPTION 2 : Normal range level(Colourcoatedroofsheets/corrugated/plain,galvanizedironsheetsonslopedM.S.pipetrussesandpurlins)

Advantages

• Isaneconomicalsolution


• Requires frequent maintenanceduetocorrosionproblems

24 ROOF

Note

vsbk design option guidelines - skat · 2017-01-24 · vsbk design option guidelines \ vii a...

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