THE STUDY OF THE DEPENDENCE OF THE RHEOLOGICAL PROPERTIES OF GELFORMING COMPOSITIONS ON THE CRACK OPENING WHEN MODELING THEIR FLOW ON A ROTATIONAL VISCOMETER

Abstract

The current period of oil production is characterized by the deterioration of the structure of oil reserves because of high water cut of the product and low oil production rates. To reduce the increased water cut, repair and insulation works are often performed. This implies in the injection of cross-linked polymer systems or the treatment of the bottom hole formation zone with polymer-gel systems. This problem is especially relevant for fractured reservoirs, which are often represented by carbonate rocks. This article is devoted to the study of the dependence of the rheological properties of gel-forming compositions on the crack opening in carbonate reservoirs. The relevance of the work relies on the rapid involvement in the development of oil fields with carbonate reservoirs which is complicated by a large number of cracks of various sizes. The types of fractured reservoirs, the development features of each type, as well as complications in the hydrocarbon production from the fracturedpore structure of the reservoir were described. The research also pointed methods and technologies for limiting water flow in cracks or pores of high permeability. The rheological properties of fluids when moving inside pores and cracks were reported. The dependence of changes in the rheological properties of the composition for limiting water inflow based on carboxymethylcellulose on the size of pores, caverns and cracks were presented. The physics of movement and formation of gel inside the fractured reservoirs, which will allow predicting changes in the gel formation time and plastic strength for each object individually was described. According to this study, it is possible to use the features of the rheological properties of gel-forming compositions to increase the efficiency of the use of water-proofing technologies for producing wells, or to align the injectivity profile of injection wells.