Development of a hydrocarbon buffer fluid system and its field testing

In the process of drilling wells when attached with a hydrocarbon-based drilling fluid, the ability of this solution to form high-viscosity non-fluid mixtures in the mixing zone occurs when interacting with a water-based grouting solution and leads to poor-quality cementing. In order to remove the crust-film of hydrocarbon from the walls of the borehole and casing with washing, as well as high-quality cementing, a system of oil-based spacer fluid (OBSF) has been developed. It is pumped into the well before the cement mortar in order to separate the drilling and cement mortar from each other and displace the hydrocarbon solution from the cemented interval, as well as to completely eliminate the formation of coagulation in the displacement zone of the hydrocarbon and cement mortar. The use of a buffer fluid of the OBSF leads to an increase in the quality of cementing, a reduction in the time spent on the selection of formulations before cementing and the elimination of losses of significant volumes of grouting and drilling fluids.