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INTERACTION BETWEEN AQ AND SULFIDITY ON YIELD AND PULP STRENGTH IN KRAFT COOKING OF MIXED NORTHERN HARDWOODS, 2002 Kraft Pulp Yield Symposium
INTERACTION BETWEEN AQ AND SULFIDITY ON YIELD AND PULP STRENGTH IN KRAFT COOKING OF MIXED NORTHERN HARDWOODS, 2002 Kraft Pulp Yield Symposium
Modified kraft cooking with polysulfide:yield,viscosity,and physical properties, 2002 Kraft Pulp Yield Symposium
Modified kraft cooking with polysulfide:yield,viscosity,and physical properties, 2002 Kraft Pulp Yield Symposium
Journal articles
Magazine articles
Understanding the risks and rewards of using 50% vs. 10% strength peroxide in pulp bleach plants, TAPPI Journal November 2018
Authors: Alan W. Rudie and Peter W. Hart | ABSTRACT: The use of 50% concentration and 10% concentration hydrogen peroxide were evaluated for chemical and mechanical pulp bleach plants at storage and at point of use. Several dangerous occurrences have been documented when the supply of 50% peroxide going into the pulping process was not stopped during a process failure. Startup conditions and leaking block valves during maintenance outages have also contributed to explosions. Although hazardous events have occurred, 50% peroxide can be stored safely with proper precautions and engineering controls. For point of use in a chemical bleach plant, it is recommended to dilute the peroxide to 10% prior to application, because risk does not outweigh the benefit. For point of use in a mechanical bleach plant, it is recommended to use 50% peroxide going into a bleach liquor mixing system that includes the other chemicals used to maintain the brightening reaction rate. When 50% peroxide is used, it is critical that proper engineering controls are used to mitigate any risks.
Journal articles
Magazine articles
Using multistage models to evaluate how pulp washing after the first extraction stage impacts elemental chlorine-free bleach demand, TAPPI Journal November 2018
Using multistage models to evaluate how pulp washing after the first extraction stage impacts elemental chlorine-free bleach demand, TAPPI Journal November 2018
Journal articles
Alkali impregnation of hardwood chips, TAPPI JOURNAL & Solutions! February 2005, Vol. 4(2) (215KB)
Alkali impregnation of hardwood chips, TAPPI JOURNAL & Solutions! February 2005, Vol. 4(2) (215KB)
Journal articles
Use of kraft recovery cycle residuals in mineralization of forests controlling leaching rates of limited soluble species
Use of kraft recovery cycle residuals in mineralization of forests controlling leaching rates of limited soluble species
Journal articles
A novel method to improve wet strength of paper, TAPPI JOURNAL & Solutions! March 2005, Vol. 4(3)
A novel method to improve wet strength of paper, TAPPI JOURNAL & Solutions! March 2005, Vol. 4(3)
Journal articles
In-situ reduction of fibrous sludge in a pulp mill aerated stabilization basin, TAPPI JOURNAL May 2005, Vol. 4(5)
In-situ reduction of fibrous sludge in a pulp mill aerated stabilization basin, TAPPI JOURNAL May 2005, Vol. 4(5)
Journal articles
Inorganic scale buildup in a bleach plant a mill case study, TAPPI JOURNAL, November 2005, Vol. 4(11) (168 KB)
Inorganic scale buildup in a bleach plant a mill case study, TAPPI JOURAL, November 2005, Vol. 4(11) (168 KB)
Journal articles
Magazine articles
Exergy and sensibility analysis of each individual effect in a kraft multiple effect evaporator, TAPPI Journal October 2019
ABSTRACT: The multiple effect evaporator (MEE) is an energy intensive step in the kraft pulping process. The exergetic analysis can be useful for locating irreversibilities in the process and pointing out which equipment is less efficient, and it could also be the object of optimization studies. In the present work, each evaporator of a real kraft system has been individually described using mass balance and thermodynamics principles (the first and the second laws). Real data from a kraft MEE were collected from a Brazilian plant and were used for the estimation of heat transfer coefficients in a nonlinear optimization problem, as well as for the validation of the model. An exergetic analysis was made for each effect individually, which resulted in effects 1A and 1B being the least efficient, and therefore having the greatest potential for improvement. A sensibility analysis was also performed, showing that steam temperature and liquor input flow rate are sensible parameters.