Meisam Mirarab Razi - School of Chemical Engineering, Iran University of Science and Technology (IUST), Tehran, Iran
Fatemeh Mirarab Razi - Mathematics and Computer Science Department, Amirkabir University of Technology, Tehran, Iran
Hamid Saadati - School of Chemical Engineering, Iran University of Science and Technology (IUST),Tehran, Iran

The aim of this study is to investigate the influence of NaCl, KCl, and CaCl2 concentration over the range of 0-20% on rheological properties, plastic viscosity and yield point, of pre-hydrated bentonite slurry following by treatments with different polymers (2.86% guar gum, 0.57% xanthan gum, 1.14% CMC high viscosity, and 4% starch). The slurries were prepared according to American Petroleum Institute procedures and rheological data were determined using a Couette viscometer. Viscometric data described well by the Herschel-Bulkley model on the basis of correlation coefficient and sum of square errors calculated for all fluids tested. Increasing salt concentration led to some significant changes in rheological properties

Drilling fluid; Herschel-Bulkley; Bentonite; Rheological Properties