Abstract
Nanofibrillated cellulose fibers produced by refining pulp fibers have interesting properties and hence can be incorporated into a papermaking furnish to help improve strength and other properties. However, nanofibrillated pulp fibers do not drain fast, therefore, it is difficult to characterize their quality using conventional drainage measures such as the Canadian Standard Freeness (CSF) or the Schopper-Reigler tests. This research studies the drainage and filtration properties of highly fibrillated pulps of nanocellulose, trying to establish the scientific basis for research on improvement in its drainage and filtration properties in the future. In this work, a novel method and apparatus for drainage and filtration testing were applied. Specific surface area of pulp Sw and specific volume Vf were calculated based on the drainage curve. The Canadian Standard Freeness values were measured and a centrifugal filtration test was conducted to provide data for analysis to characterize their properties.