Impact Of Reversible Invert Emulsion Drilling Fluid Rheology On Productivity

Abstract

Abstract Drilling muds are multi-component fluid systems designed to perform several functions during drilling operation and as a drill-in fluid under varying conditions of temperature and pressure. The use of conventional oil-base mud for drilling can bring with it an associated trade-off in formation damage. For a drilling engineer, oil-base muds control reactive shales, improve penetration rates and enhance overall drilling efficiency. For a reservoir engineer, the oil-wet state of the wellbore and filtercake may present a skin challenge. Reservoir productivity impairment resulting from using oil-base mud takes many forms. It may relate to plugging of completion equipment and gravel packs by poorly displaced oil-wet filtercake. Due to this oil-wet state, oil mud filtercakes and other oil-wet materials deposited during the drilling process are not easily dispersed or removed by cleanup chemicals. Emulsions composed of non-dispersed oil mud and displacement fluids often remain within the wellbore. During production operation, the flow from thereservoir can mobilize these oil-wet materials, plugging completion equipment and pore space. This may significantly impair well performance regardless of its design purpose. The most obvious solution for avoiding oil mud related productivity impairment would be to drill the formation with water-base mud. However, drilling engineers often use oil-base muds to minimize risk and efficiently reach extended drilling targets. The problems associated with oil-mud filtercake cleanup and change over operation during completion operations has prompt this study. Operators and service companies develop and apply novel technologies to improve drilling efficiency and maximize hydrocarbon recovery. This paper presents a review on the principle behind formulation and development of reversible mud with nano additives that will eliminate the hard choice that the drilling engineers have to choose between improving drilling performance and decreasing the risk of completion impairment; they can have both requirements in a single mud system.