Formulation of microfibrillated cellulose in vertically stirred media mills

• Main Author: Pinkney, Suzanne Zoe Renny
• Published: University of Birmingham 2016
• Subjects: 660; TP Chemical technology
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.687558

Vertical stirred media mills have been used to reduce the particle size of minerals such as calcium carbonate. In this thesis vertical stirred media mills are used to mill cellulose in order to produce microfibrillated cellulose. The cellulose is co-ground with calcium carbonate to produce FiberLean™, a patented composite invented at Imerys and used as a paper additive in order to increase the percentage of filler. In a batch laboratory scale vertical stirred media mill the effects of energy input, composition, media density and impeller tip speed on the characteristics of FiberLean™ and the effects of these variables on the media movement in the mill using Positron Emission Particle Tracking is also studied. At pilot scale the effects of media volume and flowrate on FiberLean™ and the Residence Time Distribution using a tower mill and a vertical stirred media mill were investigated. This thesis has helped to understand this new, innovative product and the effect of process variables on the quality of FiberLean™.