Comparative analysis of reagents-inhibitors of swelling of clay deposits used in Eastern Siberia

Abstract

The relevance. The subsalt structural complex of Eastern Siberian deposits includes Ordovician deposits, which are mainly represented by sandy loams, loams, clays, siltstones, marls and dolomites. The subsalt complex consists of mudstones, dolomites, limestones, as well as their intercalation. When drilling oil wells, a large number of complications can cause swelling of clay rocks: sticking of a drilling tool, cavern formation, gland formation, expansion of the wellbore, loss of circulation, etc. The drilling fluid must have a high inhibitory ability to minimize the swelling rate. The main aim of the research is to study the inhibiting property of reagents, which represent compositions of amines, polyamides and some other compounds. Object: drilling fluid used in the fields of Eastern Siberia. Methods. To define the linear swelling of clay the authors have used the Linear Swellmeter OFITE model, which determines the hydration or dehydration of clays and clay rocks by measuring the change in the linear dimensions of the clay sample. The effect of inhibitor reagents on drilling fluid rheological parameters was studied using traditional methods. Results. It was found that MgCl*6H2O and NaCl salts, which structure water molecules, reduce the swelling of clay powder. All the studied inhibitor samples to varying degrees affect the parameters of the drilling fluid, Ingidol B and Ingidol Sil were the most favorable for use in fresh clay drilling mud based on unmodified bentonite clay. The remaining samples can also be successfully used during further processing of the solution to control the rheological parameters and the filtration index after additional studies.