Physical and Numerical Simulations of Steamflooding in a Medium Crude Oil Reservoir, Lake Maracaibo, Venezuela

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractPhysical and numerical simulations of steamflooding were carried out to determine the technical feasibility of applying this technology to a medium crude oil reservoir (25° API) located in the Lake Maracaibo, Western Venezuela, specifically, 3 rd phase LL-03 reservoir. A one-dimension cell with steam injection (80% quality and 400 psi) was used to study the steamflooding behavior at laboratory scale. Oil rates cumulative oil productions and temperature profiles were reported and the results showed an increase of 14-20 percent of oil recovery with respect to original oil in place after waterflooding. Additionally, the use of steam drive as primary recovery method showed an additional of 5% in cumulative oil production. Compositional-thermal numerical simulations were carried out and validated using the laboratory scale results. Based on analysis of the crude oil true boiling point curve, the oil fraction was represented by a three pseudocomponents model. The results (oil rates and cumulative oil productions) showed a reasonable match between the calculated and experimental simulations.Using this model, a numerical simulation study was carried out in a seven-spot inverted pattern (300 m) in order to provide performance forecast and other useful information for the design, implementation and operation of a field scale steamflooding test. After seven-year of steamflooding, the simulation showed only 15 percent of incremental oil recovery in comparison with waterflooding. However, using a five-spot inverted pattern (100 m), 2.5-fold increase in cumulative oil production can be predicted with respect to waterflooding during the same period. Based on these results, it can be concluded that steamflooding technology in a Lake Maracaibo medium crude oil reservoir (25° API) represents a feasible alternative with high potential applications.