The prospect of utilising local starches as fluid loss control agents in the petroleum industry

Abstract

Fluid loss into formation is due to greater hydrostatic pressure exerted on the formation. This phenomenon may give severe drilling problems such as stuck pipe, formation damage and poor cementing job. Thus, the use of fluid loss control agent could reduce the tendency of fluid loss into formation. Currently, polyanionic cellulose (PAC) is one of the fluid loss control agents that are widely used to control fluid loss. Since the PAC has to be imported at a high price, thus there is a need to look for cheaper local materials to substitute PAC. This paper discusses the prospect of utilizing local starches, namely sago and tapioca, as fluid loss control agents in water-based mud. This discussion is based on the results derived from laboratory experiments. In this study, the performance of sago and tapioca starches were compared to PAC. Experimental results revealed that sago and tapioca starches could achieve the viscosity produced by PAC. For a given mud viscosity, it was found that sago mud could give comparable gel strength and yield point as compared to PAC mud. The significant advantage of utilizing sago mud was it could produce a thinner mud cake than PAC mud. Surprisingly, both samples were found to give comparable values of fluid loss. Based on this preliminary study, it could be concluded that local starches especially sago has the potential to be used as fluid loss control agent in drilling mud.