Kupanga mapepala a bamboo ku China ndi mbiri yakale. Bamboo fiber morphology ndi kapangidwe ka mankhwala ali ndi mawonekedwe apadera. Wapakati CHIKWANGWANI kutalika ndi yaitali, ndi microstructure wa CHIKWANGWANI cell khoma ndi wapadera, kumenya mu mphamvu ya zamkati chitukuko ntchito ndi zabwino, kupereka bleached zamkati zabwino kuwala katundu: mkulu opacity ndi kuwala coefficient kumwazikana. nsungwi yaiwisi lignin zili (pafupifupi 23% mpaka 32%) ndi apamwamba, kudziwa zamkati kuphika ndi apamwamba alkali ndi sulfide (sulfide zambiri 20% mpaka 25%), pafupi coniferous nkhuni; zipangizo, hemicellulose ndi silicon zili apamwamba, komanso kuchapa zamkati, mowa wakuda evaporation ndi ndende zida dongosolo ntchito yachibadwa wabweretsa mavuto. Komabe, nsungwi zopangira sizinthu zabwino zopangira mapepala.
Tsogolo nsungwi sing'anga ndi lalikulu mankhwala zamkati mphero bleaching dongosolo, kwenikweni ntchito TCF kapena ECF bleaching ndondomeko. Nthawi zambiri, pamodzi ndi kuya kwa delignification ndi mpweya delignification wa pulping, ntchito TCF kapena ECF bleaching luso, malinga ndi chiwerengero cha zigawo bleaching osiyana, nsungwi zamkati akhoza bleached kuti 88% ~ 90% ISO whiteness.
Kuyerekeza kwa bamboo ECF ndi TCF bleaching
Chifukwa cha kuchuluka kwa lignin wa nsungwi, zimayenera kuphatikizidwa ndi ukadaulo wozama komanso ukadaulo wowunikira mpweya kuti muwongolere mtengo wa Kappa wa slurry kulowa ECF ndi TCF (omwe akulimbikitsidwa <10), pogwiritsa ntchito Eop yopititsa patsogolo magawo awiri a ECF bleaching sequence, acid pretreatment kapena Eop two-stage bleaching sequeach TCF zamkati mpaka kuyera kwakukulu kwa 88% ISO.
Kapangidwe ka bleaching kwa zinthu zosiyanasiyana zopangira nsungwi zimasiyana kwambiri, Kappa mpaka 11 ~ 16 kapena kupitilira apo, ngakhale ndi magawo awiri oyeretsa ECF ndi TCF, zamkati zimatha kufikira 79% mpaka 85%.
Poyerekeza ndi TCF nsungwi zamkati, ECF bleached nsungwi zamkati ali zochepa bleaching kutaya ndi kukhuthala apamwamba, amene zambiri kufika oposa 800ml/g. Koma ngakhale TCF bleached nsungwi zamkati zamakono, mamasukidwe akayendedwe amatha kufika 700ml/g. ECF ndi TCF bleached zamkati khalidwe ndi mfundo yosatsutsika, koma kuganizira mozama za ubwino wa zamkati, ndalama ndi ntchito ndalama, nsungwi zamkati bleaching ntchito ECF bleaching kapena TCF bleaching, sikunakwaniritsidwebe. Opanga zisankho zamabizinesi osiyanasiyana amagwiritsa ntchito njira zosiyanasiyana. Koma kuchokera ku chitukuko chamtsogolo, nsungwi za ECF ndi TCF bleaching zizikhalapo kwa nthawi yayitali.
Othandizira ECF bleaching luso amakhulupirira kuti ECF bleached zamkati ali bwino zamkati khalidwe, ndi ntchito mankhwala ochepa, mkulu bleaching dzuwa, pamene dongosolo zida ndi okhwima ndi khola ntchito ntchito. Komabe, olimbikitsa ukadaulo wa TCF wothira bleaching akuti ukadaulo wa TCF wothira bleach uli ndi ubwino wokhala ndi madzi otayira pang'ono kuchokera pafakitale yowulira, zofunikira zochepa zotsutsana ndi dzimbiri pazida, komanso ndalama zochepa. Sulphate nsungwi zamkati TCF klorini-free blekning mzere kupanga utenga theka-chatsekedwa bleaching dongosolo, bleaching zomera mpweya wotayidwa akhoza kulamulidwa pa 5 mpaka 10m3/t zamkati. Madzi onyansa ochokera ku gawo la (PO) amatumizidwa ku gawo la oxygen delignification kuti agwiritsidwe ntchito, ndipo madzi onyansa ochokera ku gawo la O amaperekedwa ku gawo lotsuka la sieve kuti agwiritsidwe ntchito, ndipo pamapeto pake amalowa mu alkali recovery. Chifukwa cha blekning popanda klorini, mankhwala sakhala owononga, zida zowonongeka siziyenera kugwiritsa ntchito titaniyamu ndi chitsulo chapadera chosapanga dzimbiri, zitsulo zosapanga dzimbiri zingagwiritsidwe ntchito, kotero kuti ndalama zogulira ndalama ndizochepa. Poyerekeza ndi mzere TCF zamkati kupanga, ECF zamkati kupanga mzere ndalama ndalama kukhala 20% mpaka 25% apamwamba, ndi zamkati kupanga mzere ndalama ndi 10% mpaka 15% apamwamba, ndalama mu dongosolo mankhwala kuchira ndi lalikulu, ndi ntchito ndi zovuta kwambiri.
Mwachidule, nsungwi zamkati TCF ndi ECF bleaching kupanga woyera mkulu 88% mpaka 90% mokwanira bleached nsungwi zamkati ndi zotheka. Pulping iyenera kugwiritsidwa ntchito mozama ukadaulo wa delignification, kutulutsa mpweya musanayambe kukhetsa, kuwongolera zamkati munjira yowutsa mulingo wa Kappa, kuyeretsa pogwiritsa ntchito blekning ndi njira zitatu kapena zinayi. Mayendedwe a ECF owukitsa a nsungwi ndi OD(EOP)D(PO), OD(EOP)DP; L-ECF bleaching sequence ndi OD(EOP)Q(PO); TCF bleaching sequence is Eop(ZQ)(PO)(PO), O(ZQ)(PO)(ZQ)(PO). Monga mankhwala (makamaka lignin okhutira) ndi ulusi morphology zimasiyana kwambiri pakati pa mitundu yosiyanasiyana ya nsungwi, kafukufuku mwatsatanetsatane ayenera kuchitidwa pa pulping ndi kupanga mapepala a mitundu yosiyanasiyana ya nsungwi asanamangidwe mbewuyo kuti apereke chitsogozo cha chitukuko cha njira zoyenera ndi momwe zinthu ziliri.
Nthawi yotumiza: Sep-14-2024
