Effects of carbon ash on rheological properties of water-based drilling fluids

• Published in: Journal of petroleum science & engineering Vol. 100; pp. 1 - 8
• Main Authors: Meng, Xianghai, Zhang, Yihe, Zhou, Fengshan, Chu, Paul K.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.12.2012; Elsevier
• Subjects: Applied sciences; Ashes; Bentonite; Bingham-plastic model; Carbon; carbon ash; Crude oil, natural gas and petroleum products; Density; Dispersions; Drilling fluids; Drilling methods and equipments. Rocks mechanics. Directional and horizontal drilling; Drilling. Casing. Preparing wells for production; Energy; Exact sciences and technology; Fuels; Prospecting and production of crude oil, natural gas, oil shales and tar sands; Rheological properties; Viscosity; drilling fluids; carbon ash; rheological properties; Bingham-plastic model; Drilling; Viscosity; Additive; Bingham plastic; Drilling fluid; Carbon; Density; Filter cake; Rheological properties
• ISSN: 0920-4105; 1873-4715
• DOI: 10.1016/j.petrol.2012.11.011

The rheological properties of drilling fluid play a fundamental role in drilling operations, and the water-based drilling fluid is based on bentonite dispersion. According to Bingham-plastic model, the influences of carbon ash and commercial rheological modifier (RM) on rheological properties of bentonite dispersion are investigated systematically from apparent viscosity (AV), plastic viscosity (PV), yield point (YP) as well as the ratio of yield point and plastic viscosity (RYP). The results indicate that the rheological properties of bentonite dispersion with carbon ash are improved markedly in YP, and especially for the low solid content of bentonite dispersion. The filtration and density test are also carried out using an API Filter Press and mud balancer respectively. From the results, it could be observed that the filtrate loss and filter cake thickness increase dramatically whereas the density of bentonite dispersion decreases slightly as the addition of carbon ash increases. Furthermore, the stability of bentonite dispersion incorporated with carbon ash is evaluated. The experimental results indicate that carbon ash is better than RM in stability. Through this study, carbon ash is an excellent potential additive for improving the rheological properties of water-based drilling fluids. ► Carbon ash is a type of industrial dust containing carbon and metallic oxides. ► The effects of carbon ash on the rheological properties are evaluated. ► The impact of NaCl and temperature on the rheological properties is investigated. ► The rheological properties are described by the Bingham-plastic model.