GeneralInformationonpaperWhatdefinespaper?Isitthecolor?Orisittherectangularshape?Pap er isrou ghl ydef inedaspla ntfibers (ty pic all ycel lul ose )orotherfibers,woventogetherthroughseveralprocesses,tocreateathinsheet. Therefore, ma ny hi storia ns ar gu eth at papy rus parc hmen tsmadeandused byEgypti answeretheearliestpaper.However ,gene rall y,itisacce pted thatCaiLun,aseco ndcenturyofficial,wa sthefatherofthis invention,ofwhich hemadefromtree pu lp fr omba rk , an dol dfi sh ingnets . Th eCh ineseknewtheimportanceofthisinventionandtriedtokeepitasecret,butitwaseven tual lyleak edtotheMuslimworldin8 th centu ry,andfinallythewesternworldinthe11 th century. 4Tra dit ion all y, conif eroustre eswerethe pap ermak ing tre es, astheyhavelongercellulosefibersthatallowthepapertheymaketobebet ter and stronger. 18 Howe ver, dueto theimprovement inpapermaki ngtec hno logy, lit era lly al ltre escan mak erel ati vel ygoodqual it ypaper. Commontr eesus edfo rpapermakingarebirches(betula),maples(acer),pines(pinus),aspen(populus),firs(abies),andmanygeneraoftrees. 16Interestingnumbersandfactsaboutouruseofpaper•Humans per yea rconsumeabo ut300 mil lionmetric tonsofpaper. 3 •42%ofthewoodharv este dforindustri aluses (not inclu dingfuelmaking)isusedtomakepaper. 7 •The pa pe r in du s try is the lar ge st co ns umer of wat er in indu st ri al ac ti vi ti es inal l Or ga ni za ti on fo r Ec on omic Co ‐ operationandDe velopment(O ECD)Countrie s. 7 •Thepaperindustryisoneofthelargestemittersingreenhousegases, theothers beingthemetal, chemic al , coal andotherindustries. 14 ItisrankedthethirdlargestemitteringreenhousegasesoutofalltheOECDcountries.7 •1/3ofthepulptomakepapercomedirectlyfromloggedtrees,1/3comingfromscrapwood,chipsfromotherindustriessuchasthefurnitureind ustry,and1/3comesfromrecyc ledpaper. 12 Howispapermade?1.Material (mostofte nwoo d),tomake thepaper.This oftenincludes woodchips,offcutsandtrimmingfromfurnitureandtimberindustry.Ifatreeiscutespeciallyforpapermaking,thelogistumbledindrumstoremovethebark,beforeputtingitinagrindertocreatewoodchipsorevensmallerpiecesofwood.2.ThematerialisboiledathighpressurecommonlywithsulfateorKraft(amixofsodiumhydroxideandso diumsulfide) 16, toremovetheligninthat make thecellul osefibers stic ktoge ther.Some fact oriesalso usesulf ite,butitisless popular.Analte rnati vetochemical trea tment istheChemi‐Thermo‐Mech anicalPulper,whichalsopro ducespulp. 16 3.Addwatertomakeslurryfromthepulp.4.Pourmixtureinbeater,whichbeatsthemixturetoreleasethenaturaladh esi vefro mthe fib ers. Thi swi llal lowthe pul ptodry and sti cktogethertob ecomepaperinth elattersteps. 9 5.Addit ive sare add edint othe mix ture. Thisinc lud escha lks , cla ys, chemicals(e.g. titan iumoxide),forfinis hingandsizin g. 9 Siz ing isanimportantparttomaking paper,asthecellulose fibersitselfwillcre ateatooabsorbentpaper,andtheinkwillsmudge.Sizingallowsforthepapertobeusedindiffer entways,someforwriting,someforpainting,andothersforotheruses.6.Squeezepulpthr oughrollersont othinmeshwiretocrea teathinlayerofpulp,andremoveexcesswater.7.Movelayerofpulpontoawoodenfeltbelttoagainremoveanyotherwater.8.Al lowthethinlayerof pulpthroughhot airdr yerandrollers, tofurt herremo vewate randcreatepape r,which arethenrolled upanddistributedtoothercompanies.htt ://www.inoutin .com/ en-41.html
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