Effect of the Molecular Structure of Polymer Dispersants on Limestone Suspension Properties in Fine Grinding

作     者：Katja Ohenoja Juha Saari Mirja Illikainen Jouko Niinimaeki 

作者机构：Fibre and Particle Engineering Laboratory Department of Process and Environmental Engineering University of Oulu Oulu90014 Finland Kemira Oyj Luoteisrinne 2 Espoo 02271 Finland 

出 版 物：《Journal of Chemistry and Chemical Engineering》 (化学与化工（英文版）)

年 卷 期：2013年第7卷第7期

页      面：606-612页

学科分类：080706[工学-化工过程机械] 0821[工学-纺织科学与工程] 08[工学] 0807[工学-动力工程及工程热物理] 082103[工学-纺织化学与染整工程] 

主　　题：Calcium carbonate CaCO3 stirred media mill polyacrylate molecular weight polydispersity index. 

摘      要：Polymer dispersants are widely used as grinding aids to reduce the viscosity of mineral particle suspensions and to improve energy efficiency during fine grinding. The authors studied here the effects of polymer dispersants of different molecular structure on limestone suspension properties in wet stirred media milling. The polymers differed in their molecular weight and PDI （polydispersity index）. Two traditionally fractionated polymer dispersants having a high PDI （over 2） and one made by controlled radical polymerization having a low PDI （1.2） were tested. It was noticed that these dispersants worked as electrosteric stabilizers and prevented the agglomeration of ground limestone particles. Their addition allowed increased solids concentrations to be used in the grinding experiments and at the same time lowered the particle size and specific energy consumption. The particle sizes obtained were about 1 μm regardless of the dispersant or its dose. The dispersant with a low PDI reduced the viscosity more than did the high PDI dispersants. The results indicate that higher solids concentrations can be used at the same dispersant dose when a low PDI dispersant is used, leading to energy savings via increased throughput. Alternatively, a lower dose of low PDI polymer dispersant than of a high PDI polymer dispersant can be used at the same solids concentration.