Evaluation of the Steam-Injection Process in Light-Oil Reservoirs

Abstract

Feasibility of steam injection for three light-oil reservoirs in different geologic settings has been evaluated. The settings studied were a waterflooded deltaic sandstone, a waterflooded vuggy dolomite, and a deltaic sandstone structural trap with a gas cap. Optimization of steam injection to take advantage of individual reservoir characteristics is demonstrated.Results show that light-oil steamfloods can be designed to take advantage of post-secondary oil-saturation distribution. The resulting project may be carried out in a considerably different fashion from that of conventional heavy-oil steamfloods.We also re-evaluated an unsuccessful light-oil steamflood (LOSF) project carried out in the past. The re-evaluation correctly predicted failure because of early steam breakthrough. The results show that by considering details of geology and displacement process physics, the recent advances in reservoir characterization and modeling tools enable us to predict the performance of these projects more accurately.

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

“…Thus, the predicted oil gravity slightly increases from 25 to 27°API. All these results are consistent with the physical simulations experiments and with previous reports in the literature 4,[8][9][10][11][12] .…”

“…These later results are attributed to a steam distillation mechanism, which "boils off" the lighter components with the concomitant increase in the percentage of oil recovery with respect to hot water displacement, as mentioned in the Introduction. Similar results have been proposed by other authors in their physical and numerical simulation studies [8][9][11][12][13][14][15] .…”

“…Thermal expansion and distillation of light hydrocarbons are the most important production mechanisms for medium/light oil. Also, enhanced solution gas drive and accelerated depletion from zones that are heated but not displaced results in very low residual oil saturation where steam displacement occurs 3,[7][8][9] .…”

Data Analytics Techniques for Performance Prediction of Steamflooding in Naturally Fractured Carbonate Reservoirs

“…The pilot operations are tried in France, Italy, Congo, Turkey, USA, Kuwait, and Saudi Arabia [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]. The first part of the data collected and used in this study is from field pilots of steamflooding in VO NFCRs reported in the literature.…”

“…To increase the size of the database, some data from pilot plants executed in highly fractured light oil NFCRs and viscous oil highly fractured sandstone reservoirs were included [35,42,44]. In addition, some experimental data were taken from studies conducted on steamflooding in fractured media available in the literature [45][46][47][48][49][50][51][52].…”