Several additives have been used in research and on an
industrial scale to improve the pulp yield and to increase
the rate of delignification. One such additive is 1,4-
dihydro- 9,10-dihydroxyanthracene (DDA), also called soluble
anthraquinone. This chemical is widely used in Japan and
some other countries, especially with the...
A survey of the pulping literature indicated
that although the kinetics of the Kraft Pulping
process has been studied in detail , very few studies
have been reported for Alkaline Sulfite /
Anthraquinone (ASAQ) pulping process. There is no
existing rate model for this pulping process. Hence,
the objectives of...
Douglas-fir wood chips from Oregon were pulped with kraft
green liquor to produce semi-chemical pulps with properties suitable
for the manufacture of corrugating medium. The effects of five cooking
variables were studied, chemical charge, chip size, bark content
of chips, pulping temperature, and liquor sulfidity. The combinations
of levels of...
Hydrogen sulfide emissions from the smelt dissolving tank area
of some kraft pulp mills exceed environmental limitations. There are
two main factors to consider in determining the cause of these emissions:
chemical equilibria and rate processes. This investigation
considers the chemical equilibria in the smelt shatter jet area (system
A)...
Fume, sub-micron aerosal particles in the combustion gases, have been identified
as a cause of extensive plugging and fouling in the heat transfer section of a kraft
recovery boiler in kraft pulp mills. After the deposition on the heat transfer surface,
fume deposits will undergo the sintering process which causes...
Production of dry particles made of titanium dioxide powder and black liquor is
the first step in a newly proposed black liquor treatment process (Frederick et. al., 1992).
This work investigates the granulation processes in a fluidized bed granulator of titanium
dioxide and black liquor. Experiments are performed in a...