Impact of formulation on the rheological and physiochemical properties of water in oil emulsion: application on drilling mud

One of the main uses of water in oil emulsions in the petroleum industry is oil-based drilling fluids due to their rheological characteristics and various functions to keep a good drilling process. To achieve these characteristics many researches have been made to establish various formulations to reply to the technical needs and also to reduce the cost of these drilling fluids and their environmental effects. In this study, we prepared five formulations of water in oil emulsions using the additives versawet and versacoat as emulsifiers, organophilic clay VG69, and calcium carbonate CaCO3. Different rheological measurements have been applied to these five formulations to understand the effect of each additive on the rheological and viscoelastic behavior of water in oil emulsions. Studying these formulations allows for choosing better the needed technical drilling fluid with the minimum economical cost and the lowest environmental effect. Microscopic observation shows that the addition of quantities of organophilic clay type VG69 less than or equal to 4 g leading to the stability of the water/oil inverse emulsions, on the other hand, for quantities greater than 4 g, the emulsions are destabilized.