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The Effectiveness of Magnesium Oxide-based Additives in Mitigating Fouling Problems in Kraft Recovery BoilersZhao, Liming 05 January 2012 (has links)
Magnesium oxide-based additives have been used in kraft recovery boilers to minimize deposit accumulation on superheater and generating bank tubes. Due to inconclusive results observed in boilers and claims made for additive effectiveness backed by little scientific evidence, only a few mills still use the additives for fouling control. A systematic study was performed to examine the effect of MgO-based additives on deposit accumulation and removal under controlled laboratory conditions, and to evaluate the additive effect in a kraft recovery boiler. The results show that while the additive coating has no effect on deposition, it could ease deposit removal if a coating greater than 5 µm can be applied on the tube surface effectively. Separate injection of additive and black liquor had insignificant effect on deposition and removal. Results of the field study show that the amount of additive collected on the tube is too small to have an impact.
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Removal of resin and fatty acids from pulp mill wastewater streamsMakris, Stephen P. (Stephen Paul) 09 January 2004 (has links)
Resin and fatty acids (RFA) are predominantly components of coniferous trees having the natural function of protecting against microbial damage. These compounds are released from wood during the pulping process and a fraction reaches the wastewater treatment system. RFA are acutely toxic to aquatic organisms at concentrations on the order of parts per million, and their presence has been linked to toxicity outbreaks in receiving waters following process upsets. The chronic toxicity of resin and fatty acids in complex effluent matrices is poorly understood. Furthermore, the role of hydrophobic, pulp-derived solids as a removal pathway from wastewater streams has not been comprehensively studied. The objectives of this dissertation have been to quantify the relationship between resin and fatty acid concentration and chronic toxicity and to determine the role of partitioning in the removal of these compounds from pulp mill wastewater streams. Field and laboratory studies were conducted to measure toxicity using the Microtox™ whole effluent toxicity and Ceriodaphnia dubia 7-day, survival and reproduction bioassays. One resin acid in particular, dehydroabietic acid, was found to account for a significant fraction of final effluent chronic toxicity. Dissolved and sorbed RFA concentrations were quantified by solvent extraction, methyl ester derivatization, and GC-FID analysis. Partitioning to suspended solids was found to be a major removal pathway for the RFA from the effluent treatment system. A kinetic model for flotation was applied and compared to experimental data. Flotation was found to be effective at selectively removing RFA bound to pulp-derived solids from pulp mill and bleach plant sewers at moderate to high pH.
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The oxidation of pulps with lead tetraacetateDetrick, Richard William 01 January 1960 (has links)
No description available.
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Longitudinal compression of individual pulp fibersDumbleton, David P. 01 January 1971 (has links)
No description available.
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An investigation of the time-dependent structural and mechanical behavior of individual pulp fibers when subjected to an applied stressHill, Richard L. 01 January 1967 (has links)
No description available.
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A study of the reaction products formed upon the alkaline peroxide oxidation of lignin-related model compounds.Reeves, R. Heath 01 January 1964 (has links)
No description available.
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An investigation of the mechanism of water removal from pulp slurriesIngmanson, William L. (William Leslie) 01 January 1951 (has links)
No description available.
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The effect of pulping, bleaching, and refining operations on the electrokinetic properties of wood fiber fines.Goulet, Mike T. 01 January 1989 (has links)
No description available.
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Hypochlorite as a third stage in the bleaching of neutral sulfite semichemical aspenJappe, Nicholas Adolf 01 January 1956 (has links)
No description available.
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The effect of sodium peroxide bleaching on the components of eastern spruce groundwoodJones, Gary Wood 01 January 1949 (has links)
No description available.
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