DEVELOPMENT OF COMPETITIVE DRILLING FLUIDS FOR HORIZONTAL DIRECTED DRILLING BASED ON BENTONITE OF CHERKASKY DEPOSIT

Abstract

Taking into account the need for the post-war reconstruction of the country’s infrastructure, the development of high-quality drilling fluids based on Ukrainian mineral raw materials becomes a particularly urgent problem. Detailed studies of the rheological properties of aqueous dispersions of Na+-bentonite from the Cherkasky deposit (Ukraine) were carried out in relation to the development of drilling fluids for horizontal directional drilling. The effect of pH, ionic strength, concentration of the solid phase, alkaline reagent (Na2CO3) and polymer additives (PAC and PAA) on the rheological properties of Na+-bentonite dispersions was studied, and the most important correlations between the specified parameters and the performance characteristics of ready-made drilling fluids for horizontal directional drilling were obtained. A new, more effective PAA polymer is proposed to improve the viscosity-speed characteristics and other indicators of drilling fluids instead of the scarce imported PAC-polymer, and its optimal concentration is determined. It was established that with the introduction of small additives (0.005–0.025 %) of PAA polymer, drilling fluid based on Cherkasky Na+-bentonite in all its rheological characteristics is not inferior to imported analogues. The joint analysis of the obtained dependencies allowed to develop the optimal technology for obtaining bentonite gel and drilling fluids based on it, the indicators of which meet the requirements of the horizontal directional drilling. Based on the results of comparative studies of the rheological properties of drilling fluids in a wide range of deformation rates (0–1312 s–1), the competitiveness of the new drilling fluids has been proven on par with the best foreign analogues. Bibl. 17, Fig. 10, Tab. 4.