Análise comparativa das propriedades de fluidos de perfuração base água com diferentes bentonitas

Abstract

Drilling a well safely is possible, among other factors, due to the correct sizing of the drilling fluid. This fluid is responsible for carrying the produced gravel to the surface and keeping them suspended during pump stops, cooling and lubricating the drill bit, stabilizing the uncased well wall, forming an impermeable coating, among other functions. To perform these functions, additives are added to the fluid. Among the possible additives, this study experimented with drilling fluids composed of two types of bentonites, typically classified as thickening agents, whose thickening power of each bentonite is gauged through clay yield. After the preparation of the drilling fluid, it is pumped through the drill string to the bit nozzles, returns to the surface through the annular space, is stored in tanks, undergoes treatment, and is pumped again, forming a closed cycle. In this present monograph, laboratory tests were conducted to measure the characteristics of the water-based drilling fluid with bentonite - density, viscosity, filtrate volume, etc. - its rheological aspects, filtration properties, and respective yields. Additionally, bibliometric analysis and theoretical background were carried out on the subject to elucidate concepts and definitions, also aiming to select the most relevant articles within the scope of this study. The obtained results confirm the relevance of the scope of the work through scientific production and the discrepancy in the rheological and filtration properties of the bentonites used. In general, one of them performs better in thickening capacity, and the other in the formation of impermeable mud cake, making it more suitable for drilling environments.