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Historical Development of Kraft Pulp Cooking
JAPAN TAPPI JOURNAL, 2009わが国の連続蒸解釜は，その多くが1960～1970年台にかけての高度経済成長期に建設された物が多数を占め，稼動30～40年を経ても，依然現役として生産し続けている。設備は年々老朽化してくるが，様々な補修や改造，操業やメンテナンスの工夫を行いながら，競争力を維持している。一方，南米や東南アジアでは近年，大型の最新型連続蒸解釜が次々と稼動し，我々の脅威となっている。本稿では，過去40年の蒸解法の変遷を紹介する。連続蒸解釜は，コンベンショナル蒸解，修正蒸解，そして近年，Lo―Solids蒸解やCompact蒸解への発展に見られるが如く，収率面，品質面，保守面，省力面等で大きく改良が見られる。蒸解促進剤の方では，AQが広く使用され，空気酸化法のポリサルファイド（PS）も一部使用されており，現在 ...
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Behavior of Eucalyptus Wood Xylans across Kraft Cooking
Journal of Wood Chemistry and Technology, 2011Abstract The 4-O-methylglucuronoxylans isolated from wood, pulp, and black liquor from six eucalyptus wood species were characterized. The 1H nuclear magnetic resonance (NMR) studies revealed that all eucalyptus wood xylans contain O-2-substituted 4-O-methylglucuronic acid (MeGlcA) groups with hexose residues (9–26%).
Andréia S. Magaton +3 more
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The Study of Kraft Continuous Cooking of Knenaf
Advanced Materials Research, 2011The paper studied the possibility of using the whole stalk kenaf as a raw material for producing high yield and good quality bleachable pulp. The stem of kenaf has two distinct parts: the bast and the core. which have markedly different chemical components and fiber morphology.
Dong Mei Yu +3 more
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Negative Poisson Ratio of Crystalline Cellulose in Kraft Cooked Norway Spruce
Biomacromolecules, 2006The tensile properties of kraft cooked Norway spruce were studied by tensile testing with in situ X-ray diffraction (XRD). Samples were of earlywood, cooked for varying times. The total lignin content of the samples was between 21.7% and 9.3%. Tensile tests with XRD were performed on wet samples, without XRD on dry samples.
Peura, M. +6 more
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Impact of dissolved sodium salts on kraft cooking reactions
hfsg, 2008Abstract This study examined the effects of inactive ions – ions not reacting with wood – during kraft cooking, which thus far have received modest attention. Six different sodium salts were added to kraft cooking liquors at two different levels of alkalinities. Delignification as well as the formation and degradation of hexenuronic acid
Johannes Bogren +3 more
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IDENTIFICATION OF RESIDENCE TIMES IN CONVENTIONAL CONTINUOUS KRAFT COOKING
IFAC Proceedings Volumes, 2006Abstract Industrial kraft cooking process producing both softwood and hardwood pulp was studied. Residence times of chips in the conventional continuous digester were modelled based on volume fractions of chips. The volume fractions were modelled as a function of a real-time modelled cooking degree profile of chips in the digester.
Rami Rantanen, Urpo Kortela
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Thermal decomposition of inorganic polysulfides at kraft cooking conditions
Nordic Pulp & Paper Research Journal, 1995The amount of lignin which needs to be removed according to the slow residual delignification phase in kraft pulping, i e residual phase lignin, has been studied as a function of the process conditions. The variebles studied were the concentrations of hydroxide ions, hydrogensulfide ions, sodium ions (ionic strength) and temperature.
Christofer Lindgren, Mikael Lindström
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SFGP 2007 - Modelling Kraft Cooking of Wood Species Mixtures
International Journal of Chemical Reactor Engineering, 2008A batch kraft cooking simulator has been developed with the purpose of simulating the cook of wood chip mixtures. Surveyed equations are modelling diffusion and simultaneous reactions inside a planar chip and external transfers in the outer liquor phase.
Gérard F Mortha, Sandeep Jain
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Kinetics of Hardwood Carbohydrate Degradation during Kraft Pulp Cooking
Industrial & Engineering Chemistry Research, 2012Most of the studies on hardwood carbohydrate degradation focus upon the understanding of carbohydrate behavior of a single wood species. These studies tend to determine the activation energies associated with the three different cooking phases and for the different reactions that participate in carbohydrate degradation.
Ricardo B. Santos +3 more
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Development of Continuous Cooking Process for Kraft Pulping
JAPAN TAPPI JOURNAL, 2008カミヤ社が1949年に連続蒸解技術を開発して以来，連続蒸解技術が商業的に注目され始め，1980年代に入ると，異なったニーズに応じて多くの連続蒸解システムが開発された。その後，生産規模及び環境保全への対応，蒸解収率の向上，操業の安定化，漂白効率の改善，最終製品の品質要求を満たすパルプ品質確保のために，COMPACT COOKING™の連続蒸解システムが開発された。2000年代になると，パルプ製造の原料である木材チップと重油の高騰から製造コストの低減を目的とした蒸解プロセスを含むプロセス面での改善が試みられている。本稿では，まず連続蒸解釜の変遷，そしてクラフトパルプ法の連続蒸解プロセスの進歩を振り返る。次に1ベッセル気相／液相釜の低温蒸解技術が開発された背景，及びこの技術の特徴について紹介し ...
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