Case Studies of Emulsion System with Nanoparticles Application for Stimulation of Stagnant Zones in Carbonate Reservoir

Abstract

A paper presents results of an industrial application of an innovative technology for oil and gas producing wells stimulation. Also, research results of a laboratory study of ESN (emulsion system with supercharged nanoparticles) physical and chemical properties under atmospheric and modeled reservoir conditions are briefly described in this paper. The technology is based on the use of an innovative emulsion system with supercharged nanoparticles (ESN) as a solution to solve two tasks at once: 1. to divert an active composition injected after; 2. to block water bearing most-permeable zones within a profile of productive interval for more than 12 months. The case studies considered in this paper focused on the technology application in two mature carbonate formations of Ural-Volga oil-gas province located in Russia. The formations have been under industrial development for almost 50 years and characterized by complicated geology and deteriorated reserves. A combination of effects of diverter and water-blocking agent, in one composition, provides significant competitive advantages, which resulted in two times increase in oil rates with a decrease in water cut of treated by the technology oil-gas producing wells. A duration of positive effect reached 14 months on average for ten treated wells, which is four times higher than a classical acidizing technology applied on the same formations. The main competitive advantages of the technology are enlarged surface charge (alteration of wettability of rock), high thermal stability (150 °C), predictable rheology (Herschel-Balkly model), reversible blocking effect and absence of negative impact on geological formation, downhole equipment and oil and gas collecting system (environmental friendly).