Amazon Bioproduct as a Potential Additive for Water-Based Drilling Fluids: Rheological Analysis and Factorial Design Evaluation

Abstract The need to reuse materials is a global tendency to reduce the amount of waste produced; besides, considering the high operational cost that drilling fluids can offer, ecological fluids have emerged as a low-cost alternative, which also adds value to local biomasses. Therefore, this work studies the compatibility of an Amazon biomass, the Andiroba oil, as an additive for water-based drilling fluids as a rheological modifier. Physical-chemical (density, pH) and rheological parameters (plastic viscosity (PV), yield point (YP), and gel strength(Gel-10 min). The andiroba-fluid showed values comparable to the standard fluid for density (1.039 g/cm3) and pH (9.93); however, the results of the rheological parameters needed to be further addressed. A Full Factorial Design with 3 factors was carried out using andiroba concentration (wt %), salt concentration (NaCl, ppm), and temperature (°C) as variables to optimize the possible conditions for using the chosen biomass, andiroba. Statistical optimization of the results, within the experimental domain studied, showed the optimum point for each parameter to obtain the best PV, YP, and Gel-10 min values that comply with Brazilian legislation, so that the optimum points were: andiroba 1 wt %, NaCl 14,800 ppm, and temperature 78.4 °C. Rheological analysis revealed that the fluids follow a Bingham plastic model at low temperatures (40 °C), while the Herschel–Bulkley model is favored at higher temperatures (80 °C). Therefore, andiroba exhibited an interesting behavior and in accordance with the legislation, presenting itself as an ecologically viable and promising alternative for further studies of fluids based on Amazonian biomasses.