Abstract: Abstract: Shenfu coal is difficult to prepare high concentration and low viscosity of coal-water slurry (CWS) due to its high fusinite content, high internal water and high oxygen content. The report used the percentage of ultrafine pulverized coal (d50 =8μm), the content ratio of two kinds of ultrafine pulverized coal (d50=6.5μm and 4.5μm) and the dispersant compound ratio as three factors to design experiment with Box-Behnken. The regression equation about the constant viscosity concentration was obtained and analysed via variance analysis. Through response surface methodology, the factors effecting on the constant viscosity concentration of coal water slurry were analysed and optimized. The results shown that, the optima formula: the percentage of 8μm was 70%，the content ratio of two kinds of ultrafine pulverized coal was 1.44 and the dispersant compound ratio was 0.33, and the predicted concentration was 59.09%. Based on the optima formula, the concentration of coal water slurry was 60.29% (approximately to the predicted concentration) through testing when the viscosity was 580mPa﹒s. In addition, the stability and rheological property of coal water slurry were improved significantly after optimization.

Key words: Key word: Shenfu coal, coal water slurry, constant viscosity concentration, modeling, response surface methodology