Effect of Carbon Dioxide on the Properties and Chemical Composition of Bentonite in Aqueous Suspension

Abstract

In the process of using drilling muds in the oil and gas reservoirs, bentonite clay accumulates, which precludes their development, if not swelling it with carbon dioxide. The objection of this paper is to present the results of the sedimentation study and the degree of bentonite swelling depending on time for suspensions with different water concentrations of solid phase and carbon dioxide. If carbon dioxide gas is introduced into the dispersion medium, 0.12% of the weight, sedimentation is completed within the first 2-3 hours with a lower value of swelling degree. Precipitates obtained in samples with gas have particle sizes and chemical composition significantly different from the reference variant. It is found that in suspensions of bentonite with carbon dioxide the concentration of silicon in the sediment decreases to 10%, which is explained by its transfer to the dispersion medium in amorphous form.