(56b) Investigation of Bentonite Swelling Kinetics Using Particle Size Analysis

Structural fluids contain more than one phase within its solution, a liquid continuous phase with solid dispersed phase. Such fluids are widely used in most of manufacturing processes: food, pharmaceuticals, paints, plastic and solvents. In drilling of oil and gas wells, bentonite is one of the main component in formulating the drilling fluids. Bentonite dispersion in water forms a viscous structural fluid. Dispersion depends on variable factors such as particles size, shape, concentration, ion type and attraction force. Viscosity measurement for these structural fluids is critical and time-consuming process. In this paper, a low swelling Ca-bentonite is activated using soda ash combined with thermal treatment. The bentonite was successfully activated to increase and Na/Ca and hence improve the swelling capacity. Swelling of bentonite was investigated using particles size analysis. The particles size distribution distortion with time and temperature was analyzed using simple kinetic chemical reactions models. The results of particles size distribution were in agreement with viscosity measurement. The swelling kinetics of the treated bentonite fits a second –order model. The activation energy and the arte constants were obtained.

Acknowledgement

The authors would like to acknowledge the support of Qatar University and KFUPM for this research.