Review of the Effect of Preservatives on the Stability of Cassava Starch-Bentonite Muds for Water-Base Drilling Fluid Formulations

Nigeria has acquired and is maintaining the status of one of the leading producers of oil and gases with estimated annual spends of over 20 Billion Dollars in the upstream sector activities. However, it is only a small portion of this that is domiciled locally. This is even though some of the inputs used in the industry can be sourced locally. It was this situation that gave rise to the NOGIC Act which mandated that some inputs like chemical/additives must have a 60% local sourcing threshold. Starch, a cassava product is one of such additives used in the industry. Copious works in literature have established a promising potential for Nigerian cassava starch as a substitute for the imported starch in the industry, for improvement of the rheological and filtration rate properties of water-based drilling fluids. Curiously, all the starches used in the industry to date are wholly imported even with the fact of Nigeria being the world’s largest producer of cassava. Therefore, there is a challenge, a gap occasioned by the ready susceptibility of cassava starch to post harvest physiological degradation. The treatment of these starches with preservatives will, therefore, address the gap.