Oil Recovery Mechanisms of Nanocatalytic In-Situ Upgrading Process in Naturally Fractured Carbonate Reservoirs

Abstract

Nanocatalytic in-situ upgrading is a novel technique for increasing heavy-oil recovery from naturally-carbonate-fractured reservoirs. In this research the effect of the gases, the catalyst, and the reaction heating on producing heavy-oil from carbonate matrix blocks are studied. Therefore, batch-mode experiments were carried out in a cylindrical core holder set-up to simulate heavy oil recovery from matrix blocks of Indiana limestone and Silurian dolomite core samples. Finally, a simple analytical method is proposed for modelling the temperature distribution in a matrix block heated by nanocatalytic in-situ upgrading process. This method is derived from the solutions of the heat conduction equation under different boundary conditions. Results demonstrate that nanocatalytic in-situ upgrading is an enhanced oil recovery process in which gas oil gravity drainage, miscibility, chemical reactions, and thermal conduction play an important role in the production of heavy-oil from carbonate matrix blocks.