mill has conducted a pilot-scale medium consistency oxygen delignification
(MCOD) trial using a proprietary reactor as part of an integrated delignification
Also the oxygen delignification
process will be upgraded and new wash presses installed.
Our current research effort can be divided into four areas: measurement and quantification of mixing in pulp fibre suspensions, improving gas-liquid-fibre contacting in oxygen delignification
and bleaching stages, utilizing mixing and reactor design to optimize generation of pulping and bleaching chemicals, and developing criteria for repulper and disperser design based on the mechanical action imposed by the units.
Marutzky and Roffael (1977) discussed the conversions of [omega]-hydroxypropiovanillon into acetovanillon (retro-aldol reaction), [alpha]-(3-methoxy-4-hydroxyphenyl)-glycerin-[beta]-guaiacylether into 3-methoxy-4-hydroxy-styryl-[beta]-guaiacylether (retro-Prins reaction) as well as [beta]-1-dilignol-units toward styryl derivatives (retro-Prins reaction) as potential delignification
reactions, which also lead to the formation of formaldehyde.
Hence most researchers have focused on surface treatment to the wood (dewaxing, delignification
, bleaching, acetylation, and chemical grafting) and using various coupling agents to improve the wood and polymer interface.
Some of his accomplishments include implementing the first MC oxygen bleaching system, studying the organic and inorganic reactions of chlorine dioxide to advance ECF bleaching, and increasing pulp yield with oxygen delignification
In addition, Metso Automation will deliver online analyzers, which will be included in the controls of the fiber line delignification
and pulp brightness, and in the causticizing controls of the white liquor plant.
To remove the dark brown colour and increase brightness, the pulp is usually bleached in several delignification
and extraction stages employing oxygen, chlorine dioxide, sodium hydroxide and hydrogen peroxide.
At Weyerhaeuser's Plymouth facility, the group was particularly interested in seeing and learning more about the mill's wood handling and preparation; pulping, oxygen delignification
and bleaching systems; chemical recovery; the use of recycled materials to make containerboard; and the mill's effluent treatment system.
Metso Paper's delivery will include the modernization of the washing and screening systems, as well as of the oxygen delignification
and bleaching processes.
92] produced sugar and ethanol from cellulosic resources like rice, straw, grass, bagasse, sawdust and newsprint, after chemical delignification
with trichoderma cellulose.
Ozone bleaching and delignification
is being used more for chemical pulps.