Modelling the effect of drilled cuttings on the rheological properties of waste vegetable oil biodiesel in water based drilling mud

Abstract

This work compares the experimental results of the effects of drilled shale on the formulated oil-in-water emulsion drilling mud using biodiesel produced from waste vegetable oil (WVO) with white oil 5# at 140 °C. The concentration of drilled shale with particle sizes distribution between 80 and 100 mesh was varied from 0 to 16 wt./vol.%. The plastic viscosity, yield point, thixotropy, high-temperature–high-pressure (HTHP) filtration loss, coefficient of friction, and rate of drilled cuttings recovery were assessed. The biodiesel-in-water emulsion drilling mud (BEDM) exhibited better rheological behavior and stability compared to white oil-in-water emulsion drilling mud (WEDM) under the different conditions examined. BEDM demonstrated the lowest HTHP filtration volume with values ranging from 6 to13 cm3 compared to WEDM with 9–18 cm3 and water-based mud (WBM) of 12–25 cm3. Moreover, coefficients of friction of BEDM, WEDM, and WBM were 0.26, 0.35, and 0.75, respectively. BEDM had the highest drilled cuttings recovery rate of 79.60%, followed by WEDM with a rate of 72.80%, while WBM recorded the least (46.25%). Hence, the use of WVO biodiesel as additive in water-based mud can enhance the drilled shale tolerance of water-based drilling mud in an environmentally friendly manner.