Date of Award


Degree Name

Master of Science


Chemical and Paper Engineering

First Advisor

Dr. Richard B. Valley

Second Advisor

Dr. David K. Peterson

Third Advisor

Dr. Ellsworth Shriver

Access Setting

Masters Thesis-Open Access


Experiments were conducted to study the effect of refining on virgin fibers as well as on recycled fibers. Interaction effects of recycling and type of treatment of virgin fibers on characteristics of secondary fiber were studied. A significant reduction in drainage properties of the furnish for both hardwood and softwood pulps were observed. This reduction in properties was found proportional to the amount of refining. It is necessary to achieve required strength properties at higher freeness values, if fibers are to be recycled. This can be done by improvement in uniformity or homogeneity of refining and by gentler and less severe fiber treatment. This also results in higher power consumption. Existing refining theories were used to correlate strength properties with refining variables and thus to obtain optimum conditions for refining in terms of development of strength properties and power consumption.