Kaʻina hana hoʻokeʻokeʻo ECF elemental chlorine-free no ka ʻiʻo ʻohe

He moʻolelo lōʻihi ko mākou no ka hana pepa ʻohe ma Kina. He kūikawā ke ʻano a me ka hoʻohuihui kemika o ka fiber ʻohe. He lōʻihi ka lōʻihi awelika o ka fiber, a he kūikawā ka microstructure o ka paia cell fiber. Maikaʻi ka hana hoʻomohala ikaika i ka wā pulping, e hāʻawi ana i ka pulp bleached i nā waiwai optical maikaʻi o ka opacity kiʻekiʻe a me ka coefficient scattering light. Kiʻekiʻe ka nui o ka lignin o nā mea maka ʻohe (ma kahi o 23%-32%), ka mea e hoʻoholo ai i ka nui o ka alkali a me ke kekelē sulfidation i ka wā pulping a me ka kuke ʻana (ʻo ke kekelē sulfidation maʻamau he 20%-25%), kokoke i ka lāʻau coniferous. ʻO ke kiʻekiʻe o ka hemicellulose a me ka silicon o nā mea maka e lawe mai i kekahi mau pilikia i ka hana maʻamau o ka holoi pulp a me ka ʻōnaehana evaporation wai ʻeleʻele a me ka hoʻohuihui. ʻOiai kēia, he mea maka maikaʻi nō nā mea maka ʻohe no ka hana pepa.

ʻO ka ʻōnaehana hoʻokeʻokeʻo o nā mea kanu pulping kemika nui a me waena o ka ʻohe e hoʻohana i ke kaʻina hana hoʻokeʻokeʻo TCF a i ʻole ECF. Ma ke ʻano laulā, i hui pū ʻia me ka delignification hohonu a me ka delignification oxygen o ka pulping, hoʻohana ʻia ka ʻenehana hoʻokeʻokeʻo TCF a i ʻole ECF. Ma muli o ka helu o nā pae hoʻokeʻokeʻo, hiki ke hoʻokeʻokeʻo ʻia ka pulp ʻohe i 88%-90% ka ʻōlinolino.

Ua hoʻokeʻokeʻo ʻia kā mākou mau ʻiʻo pulp ʻohe i hoʻokeʻokeʻo ʻia me ka ECF (ʻaʻohe chlorine elemental), kahi i emi ai ka nalowale o ka hoʻokeʻokeʻo ʻana ma ka pulp ʻohe a ʻoi aku ka mānoanoa o ka pulp, ma ke ʻano laulā e hiki aku ana ma mua o 800ml/g. ʻOi aku ka maikaʻi o ka pulp o nā ʻiʻo ʻohe i hoʻokeʻokeʻo ʻia me ka ECF, hoʻohana i nā kemika liʻiliʻi, a he kiʻekiʻe ka pono o ka hoʻokeʻokeʻo ʻana. I ka manawa like, ua oʻo ka ʻōnaehana lako a paʻa ka hana hana.

ʻO nā kaʻina hana o ka ECF elemental chlorine-free bleaching o nā ʻiʻo ʻohe: ʻo ka mua, hoʻokomo ʻia ka oxygen (02) i loko o ka hale kiaʻi oxidation no ka oxidative delignification, a laila hoʻokō ʻia ka D0 bleaching-washing-Eop extraction-washing-D1 bleaching-washing ma ke kaʻina ma hope o ka holoi ʻana. ʻO nā mea hoʻomaʻemaʻe kemika nui ʻo CI02 (chlorine dioxide), NaOH (sodium hydroxide), H202 (hydrogen peroxide), a pēlā aku. ʻO ka hope loa, ua hoʻokumu ʻia ka pulp bleaching e ka dehydration kaomi. Hiki i ke keʻokeʻo o ka ʻiʻo pulp ʻohe bleaching ke piʻi ma mua o 80%.