Study of the use of Buca clays as drilling mud

The bentonite with high swelling property is used in a wide range of areas from food to medicine industries.The ever-growing increase in the demand of bentonite in various industries in the world and our country has rendered obligatory the use of mixed and calcium bentonites with high reserves. While Na-bentonites are used as drilling fluid for their naturel physical properties, lower quality calcium and mixed bentonites have limited use in this industry. The physical properties of such bentonites need to be improved by the application of concentrating and alkali activation. In this study, calcium bentonite from Buca region was activated with sodium carbonate indifferent proportions, and changes in filtrate behaviours and rheological properties during activation were examined. Bentonite and sodium carbonate were mixed at certain proportions and kept for different time periods so that twenty one different mixtures could beprepared. Changes in the rheological properties such as plastic viscosity, yield point and determination of residues with a diameter longer than 75 micron depending on the amount of sodium carbonate in activation and the elapsed time have been evaluated. In this context, different commercial bentonite samples were taken and evaluated using the procedures and standards of foundry and drilling bentonite testing methods. The results were evaluated based on TS EN 13500 standards and in comparison with theresults obtained from other commercial bentonite samples. The laboratory studies were also supported by chemical analysis, XRD and SEM analysis.