Abstract: Aiming at solving the problems of low concentration,poor fluidity and atomization of coal water slurry produced by single mill process,the theory and method of particle size gradation was systematically studied,and the three-peak fractal gradation of coal water slurry could be realized by adding fine slurry and ultra-fine slurry.Theory and industrial application of coal water slurry concentration technology based on three-peak fractal gradation in Shanxi Yangmei Fengxiquanzi Energy Co.,Ltd. were analysed. Results show that coal slurry concentration increases from 60.10% to 64.19%,and the effective gas content increases from 79.91% to 82.12%.Specific oxygen consumption and specific coal consumption decrease by 35 m~3/km~3 and 20 kg/km~3,while ammonia consumption per ton of ammonia decreases by0.05 t,and the amount of ammonia per ton of coal increases by 0.024 t.The three-peak fractal gradation concentration technology has advantage of high pulp concentration and efficiency,wide adaptability of coal types and lower energy consumption,which will instead of conventional bar mill pulping process.