Reagentless Preparation of Formation Water for Reservoir Pressure Maintenance System in Low Permeable Oil Reservoirs. Water Ozonation Method

Abstract

Abstract Currently, oil fields with complex reservoir properties are involved in the development of Russian oil Company (for example, Severo-Danilovskoye, Danenberg, Vostochno-Tokayskoye field (Korotkova M.H. et. al, 1998)), in which high requirements are imposed on the degree of preparation of formation water for injection into the reservoir pressure maintenance system. The supply of prepared water to the reservoir pressure maintenance system significantly improves oil production conditions and slows down the deterioration of reservoir properties. This ensures the displacement of oil from a larger number of pore-fractured channels, which increases the oil recovery factor. In this connection, the technology capable of solving the problems of preparing formation water for the reservoir pressure maintenance system at fields with low permeability of oil reservoirs is considered for implementation in the present work. Also, the solution of the production problem of cleaning the injected agent into the reservoir pressure maintenance system from hydrogen sulfide is considered to prevent deterioration of reservoir properties of the formation. The reagent-free method of formation water preparation is proposed as the described technology, in this case, the ozonation method. The main technological advantage of this method is the possibility of simultaneous purification of contaminated formation water from oil products and bacterial impurity, which can cause contamination of the formation with sulfate-absorbing bacteria (SHvelev T.G.,2005).