轻化工程漂白Chapter-1

Chapter1

TechnicalDevelopmentTendencyofPulpandPaperIndustry

1.1GeneralDevelopmentTendencyofPaperScienceandTechnologyLargescale,Automation,Informationality,HighefficiencyOptimizedandsimplifiedprocesssystem,integrationandintelligenceofprocesscontrolReduceinvestmentandenergyconsumption,improveproductqualityanddecreaseproductioncostDevelopgreatlytotherecycledeconomyandcleanproduction,utilizeresourcesmoreefficiently,reduceenvironmentpollution,promotethesustainabledevelopmentofpaperindustry1.2DevelopmentTendencyofChemicalPulping

MainMethods:KraftandSoda-AQMainProcesses:RDH,Super-Batch,EMCC,Lo-Solids,DDSPurposeachieved:Highefficientdelignification

Gooddelignifyingselectivity Lowenergyconsumption LessenvironmentalimpactChemicalsused:NaOHNa2SAQPolysulfide

(Na2Sn)MinorMethods:SP,AS,NS,AS-AQProductionscale:singleline1milliont/aofwoodpulp

3500t/dofwoodpulp

750t/dofbamboopulp

NewTechnologies:Kvaerner－Compactcooking

Dualoxtwo－stageoxygen

delignification

Andritz－Lo-Solidscooking

Metso－SuperBatchcooking

Oxytractwo-stageoxygen

delignification

1.3DevelopmentTendencyofMechanicalandChemimechanicalPulpingProcessesused: TMP

CTMP BCTMP APMP,PRC-APMP CMP,Bio-CMPChemicalsused: Na2SO3

NaOH,H2O2 Enzyme

Chelatingagents: EDTA,DTPA,DTPMPAPurposeachieved: Highyield

Goodstrength Goodbrightness LowpollutionPRC－APMP

•P－Preconditioning

•RC－Refinerchemical

•APMP－AlkalinePeroxideMechanicalPulp

Projectsbuiltorbeingconstructed

•HunanYueyang100000t/a

•HenanPuyangLongfeng100000t/a

XinxiangXinya100000t/a

JiaozuoRuifeng150000t/a

•NingxiaMeili100000t/aPRC－APMPQualityControllablepulpqualitywhichcanmeetthedemandofdifferentspeciesofpaperPoplarPRC－APMP:beatingdegree55－80ºSR（SchopperRiegler）

CanadianStandardFreeness（CSF）80-150mLBreakingLength>3200m（Max6000m）Brightness78－80％ISO（Max82％ISO）LightScatteringCoefficient45m2/kg（Max54m2/kg）Attheconditionofhighbreakinglength,keepinghighbulk,average2.2cm3/g,max3.0cm3/gLowcontentofshive,average0.1%

1.4DevelopmentTendencyofPulpBleachingBleachingsequences:ForChemicalPulp:OQP DQP D(EOP)D OD(EO)P,OD(EP)D,OD(EOP)D C(EP)H,C(EP)HP OHQP

ForTMP,CTMP,DIP: P,Y,FAS(Formamidine sulphinicacid) PY P-FAS Stageprobablyused: X,Pa,PxChemicalsused:

ClO2O2H2O2NaOH,Na2SiO3DTPA,EDTAPa,Px,PxaXylanaseAdvancedBleachingSequencesGermanyStendalPulpMill0.6M•t/asoftwoodpulp87－89%ISOECF：Q－(OP)－D－(PO)TCF：Q－(OP)－Pa－(PO)SwedenOstrandTCF：Q－(OP)－(ZQ)－(PO)88-90％ISO,Effluentdischarged5-6m3/tpulpFinlandonepulpmillshort－sequencebleaching:D(EOP)D,Brightness85%,88%ISOand90%ISOGuizhouChitianhua:bamboopulpTCF:Q－(OP)－Q－(PO)ECF:Q－(OP)－D－(PO)Purposeachieved:

Highbrightness Highbrightnessstability Highbleachedpulpyield Lowviscosityloss Lowenergyandwaterconsumption Lowpollutionload(COD,BOD,SS, AOX)1.5DevelopmentTendencyofWastePaperRecyclingDrumPulper:lowshearforce,highconsistency15-18%HighefficientscreeningandcleaningScreeningwithlowandmediumconsistency,slot≤0.15mmCleanerforheavyorlightcontaminantsEffectiveremovalofstickiesHighefficientdispersingtechniqueHighefficient,lowenergyconsumptionfloatationequipmentOxidative－reductivebleaching:P、Y、FASorcombinedHighefficientwastewatertreatmentsystemFreshwaterconsumption≤5m3/tpulp1.6DevelopmentTendencyofPapermakingForpapermaking,stressonthedevelopmentofproductiontechniquescharacterizedbylowbasis-weight,highquality,lowconsumptionandhighefficiencyForpapermachineandpaperboardmachine,turntowardswidewidth,highspeed,highefficiency,lowconsumption,andtheincreaseofunitproductioncapacityaswellasthenewtechniqueofpapersurfacetreatment.(b)

Purposesachieved:ImprovementofpapermachinerunnabilityIncreaseofpaperandpaperboardproductionImprovementofproductqualityEnhancementofenterprisecompetitivepowerPapermachineMaxwidthofnewsprintmachineandsupercalender:11.3mClosedoperationfromsheetformationtodrying,automaticsheettransferring,automaticreelchangingChangesofcoatingandcalenderingfromoutermachinetoinnermachineEnergyandwatersavingNewsprintstreamconsumption1.1－1.4t/twaterconsumption10－12m3/tImprovedqualityFuturedevelopmentfocusonhigherspeed,butnowiderThepapermachinespeedwillreach3000m/mininthenext10yearsNewtechniquesinculturepapermachineHighefficient,compactstockflowsystemSmallervolume,shorterflowpath,bettermixinganddegassing,moreaccuratefurnishandconsistencycontrolHydraulicheadboxwithdilutedwatercrossbasisweightcontrolNewgenerationoftwinwireformerwithvacuumformingrollandpressurizeddewateringplateShoepressIncreasethemachinespeedto1500m/min→1800m/minIncreasethedrynessofwetweb3~8%Savethedryingenergy12－32％

Improvebulk,crossmoistureprofileDryingTechniqueSinglerowdryerRopefreesheettransferringSinglefelt(dryscreen)operationImprovetheuniformityofcrossshrinkageIncreasedryingcapacityCoatingandCalenderingTechniquesMergepapermaking,coatingandcalenderingintoamachine,realizetheon-lineproductionofcoatedpaperPremeasurementsizingpressDoublerollsoftcalenderingtechniqueSupercalendercoveredwithpolymerCurtaincoating,spraycoatingEngineeringpigment,nanometerpigment(c)

TechnologiesandproductsfocusedonHighefficiency,lowenergyconsumption,mediumconsistencypulpbeating(especiallyfornon-woodandrecycledpulp)Newtechniqueofproducinghighgrade,light-coatedwritingandprintingpaper(offsetnewsprint,offsetprintingpaper,light-weightcoatedpaper,China’sartpaper,etc)CoatingformationandadvancedcoatingtechnologyofpaperandpaperboardNewtechniqueofproducinghighgradepackagingpaperandpaperboard(coatedfoldingboard,coatedwhiteboard,Kraftlinerboard,highstrengthcorrugatingmedium,etc)Advancedtechnologyofproducingspecialtypaper,functionalpaperproductandpaper-basecomposite(carbonlesscopypaper,thermosensitivepaper,pressuresensitivepaper,computer-printingpaper,specialsyntheticpaper,pulpmouldproducts)Advancedtechnologyofproducinghighgradetissuepaperanddisposableproducts(d)

PaperChemicalsused:lSizingagents

Dispersingrosinsize Alkylketonedimmer(AKD) Alkenylsuccinicanhydride(ASA)lWhitemineralpigments Calciumcarbonate(GCC,PCC) Titaniumdioxide Kaolin TalclPaperstrengthagents Starch(OS,CS,AS,AmS) PAM(CPAM,APAM,AmPAM) PVA(Polyvinylalcohol) PAE(Polyamideamine-epichlorohydrine) PEI(Polyethyleneimine)l

Retention-aidsanddrainage-aidsCompozilTMCPAMAPAMCS(CationicStarch)PEO(polyethyleneoxide)PEO/CF(co-factor)SomeCo-factors:PFR(phenolformaldehyderesin)MPFR(Modifiedphenolformaldehyderesin)SNS(Sodiumnaphalencesulphonate)1.7DevelopmentTendencyinPollutionControlandEnvironmentalProtectionMoreandmoreattentionwillbepaidinpollutioncontrolandenvironmentalprotectioninthefuture.

3R—Reduce,Reuse,RecyclePulpandpapercleanproductionAlkalirecoveryfromblackliquorofbothwoodandnon-woodpulpBiorefinery-anewwayoffullyutilizationofplantfiberresourcesLigninmodificationandutilizationTreatmentandutilizationofsolid-wasteTreatmentofscreening,cleaningandbleachingeffluentwithcoagulating-biochemicalprocessTreatmentandreusingofwhitewaterinpapermakingprocess1.8DevelopmentTendencyinProcessEnergySavingandCarbonReducingEnergysavingandheatrecoveryinchemicolpulpingEnergysavingandheatrecoveryinmechanicalpulpingandchemimechanicalpulpingEnergysavinginpulpwashing,screeningandbleachingEnergysavingandheatrecoveryinalkalirecoverysystemEnergysavingandresourceconprehensiveutilizationofsecondaryfiberrecyclingEnergys