DEVELOPMENT OF THE COMPOSITION OF THE GROUTING SOLUTION FOR FIXING WEAKLY CEMENTED ROCKS IN THE BOTTOMHOLE ZONE OF THE FORMATION

Abstract

The negative effects of sand removal from the formation and methods of avoiding the formation of sand crusts at the bottom of wells are considered. The reasons for the destruction of the bottomhole zone during the operation of wells with unstable reservoirs and ways to reduce the flow of sand into the well are presented. The use of chemical methods is one of the most effective methods of preventing sand from entering the well, which is used in Ukraine and abroad. The article analyzes the scientific, technical and patent literature of the developed compositions used for fixing rocks in the bottomhole zone of the formation. The advantages and disadvantages of grouting compositions and their compositions used for rock fixing are presented. Based on the results of experimental studies, the composition of the grouting mortar was developed to create a cement stone in the bottomhole zone of the formation with appropriate values of compressive strength and gas permeability. The results of measurements of the technological characteristics of the grouting mud and the formed cement stone using standard recording equipment are presented. Based on the results of experimental studies, graphical dependences of the compressive strength of cement stone and the permeability coefficient of stone on the content of swollen perlite in the grouting solution were constructed and analyzed.The optimum value of the content of swollen perlite in the solution was determined, which ensures the appropriate values of compressive strength (up to 4 MPa) and gas permeability (up to 3.47 n2) of cement stone. The use of the developed composition makes it possible to increase the flow rate of gas wells with unstable reservoirs and improve their operating conditions by preventing the flow of sand from the formation into the well.