Effect of Nano silica on Portland Saudi cement type 'G' in high pressure high temperature applications.

摘要

Nano silica has been introduced in recent years as an additive for concrete mixture in construction applications. Addition of Nano silica results in improved cement mechanical properties and time dependent properties. Only limited research on the application of Nano silica in oil and gas well cementing has been reported. In this study, the effect of addition of Nano silica on Portland Saudi cement type 'G' at high pressure and high temperature has been investigated. Nano silica was added at 1.0%, 2.0% and 3.0% to the cement slurry mixture currently used for oil/gas well cementing in Saudi Arabia. Experimental investigations addressed different cement slurry properties such as thickening time, fluid loss, free water separation, rheological properties, compressive strength, static gel strength, density, particles settling, and shrinkage/expansion. The results of the research showed that addition of only 1.0% and 2.0% Nano silica was feasible. Moreover, the results showed that the addition of Nano silica affected most of the addressed cement slurry properties.