Определение дисперсной фазы буровых растворов на полимерной основе

Abstract

The purpose of the article is determination of the volume of the polymer solution dispersed phase, estimation of their subordination degree to the power law of fluid flow, as well as determination of the rheological model of mud flow in order to calculate the pressure losses under fluid movement in the elements of the circulation system. Water-soluble polymers are widely used in the composition of drilling fluids and are also used independently as flushing fluids for drilling wells. Despite the wide application range of polymers, when drilling little attention is paid to the volume of the dispersed phase resulting from the dissolution of polymer in water. Particular interest is caused by so-called dilute solutions (term used in the theory of polymer solutions). They are little mentioned in drilling but their number of macromolecular coils of the polymer reaches such a value that they do not interact with each other when the fluid flows. Using a viscometric method, the molecular mass and the characteristic viscosity of each solution used for the dispersion phase volume determination are estimated. The parameters of the rheological power law are determined through the application of rotametric viscometry. As a result, it has been found out that the solutions of the considered polymers prepared for the study are referred to diluted. On example of one of them the possibility of determining the relative volume of macromolecular coils of polymer with the immobilized solvent (water) is shown. It is demonstrated that a change in the specified volume causes a change in the parameters of the rheological power law of researched solution flow. The proposed methods for determining the relative volume of the dispersed phase of drilling muds based on dilute polymer solutions allows to adjust the rheological properties of flushing fluids and set the parameters of the rheological power law describing the flow of pseudoplastic fluids.