阴离子分散剂对酸化膨润土流变性的影响

Effect of Anionic Dispersant on Rheological Properties of Acid-bentonite

研究了阴离子分散剂聚丙烯酸钠对质量分数为10%的酸化膨润土分散体系流变性的影响.结果表明,添加0.4%分散剂的分散体系的剪切应力、表观黏度和屈服应力最低.其它体系流体均表现为从假塑型到胀流型流体的转变,而含0.4%分散剂的体系始终表现为胀流型流体.采用Herschel-Bulkley模型对各体系的流变曲线进行了拟合,得到较好的拟合曲线,同时探讨了酸化膨润土分散体系的流变机理.

The effect of anionic dispersant （sodium polyacrylate） on rheological properties for 10% （mass fraction） aeid-bentonite dispersion were studied. The results show that, among dispersion containing disper- sant dosage of 0.2%, 0.4%, 0.6% and 0. 8%, respectively, the dispersion containing 0.4% dispersant has the lowest shear stress, apparent viscosity and yield stress. In range of studying shear rate, dispersion eontai- ning 0.4% dispersant exhibited dilatant characteristic and others transformed rheology from pseudoplastie to dilatant eharacteristic. The result also show that the rheograms fitting Hersehel-Bulkley model are well. The mechanism of rheological properties on acid-bentonite dispersion was also diseussed.