Date of Award


Degree Name

Master of Science


Chemical and Paper Engineering


Paper Engineering, Chemical Engineering and Imaging

First Advisor

Dr. E. H. Shriver

Second Advisor

Dr. R. L. Janes

Third Advisor

Dr. John Crowell

Access Setting

Masters Thesis-Open Access


The main objective of this study was to investigate the effects of steam explosion on the optical properties of recycled fibers, i.e., brightness, opacity, scattering and absorption coefficients, and to find out whether explosive discharge caused fiber damage and affected fiber bonding ability.

Laser printed paper was pulped by the steam explosion process. Addition of two different chemicals, residence time, pressure, and dispersant level were varied during the steam explosion experiments. All factors were kept at two levels.

Full factorial design and regression analysis were applied to determine the effect of different factors on steam explosion pulp. The data indicate that steam explosion removed the toner from the laser paper and dispersed these particles in the pulp. As a consequence of high scattering coefficient and low absorption coefficient of the steam exploded pulp, the sheet brightness and opacity were higher compared to unexploded pulp. The fiber bonding ability of steam exploded pulp was reduced which resulted in lower tensile strength and relative bonded area compared to unexploded pulp. Zero span breaking length of steam exploded pulp was lower than exploded pulp which means that steam explosion caused damage to the fibers.