煤浆浓度和颗粒分布对煤浆黏度预测的影响

Influence of concentration and particle size distribution on viscosity prediction of coal slurry

采用神华煤制备煤浆,分析了颗粒粒径比λ和小颗粒体积分数ξ对双峰分布浆体黏度的影响,根据浆体黏度的关联式预测了煤浆的黏度并且与实验结果进行了比较。结果表明,采用双峰分布的颗粒制浆可以有效地降低浆体的黏度,同时可以获得较大的浆体体积分数。在相同体积分数下,随着颗粒粒径比λ的增加,浆体的黏度迅速下降。当小颗粒体积分数ξdp1为35%时,浆体的黏度最小。采用Ouchiyama模型计算浆体的最大体积分数m与实验值较为吻合,而浆体的本质黏度[μ]基本保持不变。考虑λ和小颗粒体积分数ξ对双峰分布浆体的最大体积分数m的影响,可以采用单峰分布浆体的黏度关联式预测双峰分布浆体的黏度。

The viscosity of slurry, which was made of Shenhua coal with bimodal distribution of particle size, was analyzed in detail. The effect of particle size ratio （λ） and different particle size volume fraction （ξ） were examined. An empirical correlation of slurry viscosity based on the experiment results was proposed. The results show that preparation the coal slurry with bimodal distribution of particle size can effectively reduce the viscosity of slurry and improve its volume fraction （φ）. With the same volume fraction, the viscosity of slurry rapidly declines as increasing particle size ratio. The viscosity of slurry is the smallest when the volume fraction of small particle is 35%. The maximum volume fraction calculated using Ouchiyama model is in agreement with the experimental values. The intrinsic viscosity[μ] keeps at constant value. If the effects of A and ξ are fully taken into account in the maximum volume fraction φm, the correlation of viscosity for single-peak distributed slurry could be used to predict that of bimodal distributed slurry.