Dimensionless parameter approach for oxygen delignification kinetics

Date

2008-08-20

Author

Dogan, Ismail
Gueruez, Gueniz

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In this study, the kinetic analysis of oxygen delignification of Turkish southern hardwood Kraft pulp was carried out. The kinetic rate data were collected in a high pressure batch reactor at industrially significant conditions of temperature, alkali charge, and oxygen partial pressure. The mass transfer effects were examined for the system studied. After eliminating the mass transfer resistances in the delignification system, the kinetics of oxygen delignification was studied and the governing rate equations were derived. The kinetics of the carbohydrate degradation was analyzed to determine the extent of delignification without the reduction in the pulp strength below the acceptable level; which is usually taken as the removal of no more than half of the lignin in the pulp entering the oxygen stage. The kappa number, intrinsic viscosity, and reaction time were expressed in dimensionless forms to generalize the results and to make them independent of the initial values, experimental conditions, and pulping conditions prior to oxygen delignification. These dimensionless parameters were fitted to nonlinear equations. These equations can also be used for the control of the oxygen delignification towers. The same approach was also used for the reported studies in the literature which allowed the comparison with the results of this study.

Subject Keywords

Industrial and Manufacturing Engineering, General Chemistry, General Chemical Engineering

URI

https://hdl.handle.net/11511/65998

Journal

INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

DOI

https://doi.org/10.1021/ie071498h

Collections

Department of Chemical Engineering, Article

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Citation Formats

I. Dogan and G. Gueruez, “Dimensionless parameter approach for oxygen delignification kinetics,” INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, pp. 5871–5878, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65998.