Extended DLVO theory applied to coal slime-water suspensions
来源期刊:中南大学学报(英文版)2012年第12期
论文作者:ZHANG Ming-qing (张明青) LIU Qi (刘颀) LIU Jiong-tian (刘炯天)
文章页码:3558 - 3563
Key words:coal slimes; kaolinite; montmorillonite; extended DLVO theory; aggregation mechanisms
Abstract: Coal slimes are mainly composed of coal and clay particles. The interaction energies among these particles were calculated using extended DLVO (DERJAGUIN-LANDAU-VERWEY-OVERBEEK) theory and the aggregation mechanisms were analyzed based on the settling experiments for coal-kaolinite and coal-montmorillonite suspensions, respectively, under different conditions of water hardness. The results indicate that for coal-kaolinite suspensions, as the water hardness reaches 10.0 mol/L, the coal particles aggregate with each other easily, and then, the coal particles may aggregate with kaolinite particles. However, no aggregation occurs between kaolinite particles. A clay platelet network is formed in coal-montmorillonite suspensions by montmorillonite particles and coal particles are captured into the network. Coal and montmorillonite particles settle completely.
ZHANG Ming-qing (张明青)1 , LIU Qi (刘颀)2, LIU Jiong-tian (刘炯天)3
(1. School of Environment Science and Spatial Informatics, China University of Mining & Technology,
Xuzhou 221116, China;
2. School of Electric Power Engineering, China University of Mining & Technology, Xuzhou 221116, China;
3. School of Chemical Engineering and Technology, China University of Mining & Technology,
Xuzhou 221116, China)
Abstract:Coal slimes are mainly composed of coal and clay particles. The interaction energies among these particles were calculated using extended DLVO (DERJAGUIN-LANDAU-VERWEY-OVERBEEK) theory and the aggregation mechanisms were analyzed based on the settling experiments for coal-kaolinite and coal-montmorillonite suspensions, respectively, under different conditions of water hardness. The results indicate that for coal-kaolinite suspensions, as the water hardness reaches 10.0 mol/L, the coal particles aggregate with each other easily, and then, the coal particles may aggregate with kaolinite particles. However, no aggregation occurs between kaolinite particles. A clay platelet network is formed in coal-montmorillonite suspensions by montmorillonite particles and coal particles are captured into the network. Coal and montmorillonite particles settle completely.
Key words:coal slimes; kaolinite; montmorillonite; extended DLVO theory; aggregation mechanisms