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The low salinity water injection (LSWI) technique is gaining popularity due to the simplicity of the method compared to other thermal and chemical EOR techniques. In this paper, a fundamental model is proposed which captures the effect of LSWI on improving the microscopic displacement efficiency from carbonates through the trapping number. The proposed model was used to history match recently published corefloods using the UTCHEM simulator. The proposed model incorporates wettability alteration effect through contact angle and trapping parameter. Results showed that history matching of the corefloods was performed successfully using the proposed model. Moreover, wettability alteration is the main contributor to LSWI effect on oil recovery from carbonate rocks. The proposed model was further validated upon which the applicability is extended to include weakly-oil-wet to mixed-wet rocks. This model can be used for oil recovery predictions from carbonate rocks at the field-scale.

Well-test permeability derived from pressure transient analysis is important information about the interwell permeability distribution of a reservoir. It is available for many active wells in a reservoir. Nevertheless, no conventional geostatistical technique is able to incorporate this information into a reservoir model. This paper describes an integrated procedure to account for well-test permeabilities obtained from several wells into a geostatistical model of a reservoir permeability distribution. Our procedure is based on a simulated annealing algorithm coupled with a steady-state, single-phase flow simulator that solves an inverse problem. A correlation is developed to relate the effective permeability of each well-test region obtained from the simplified simulation with the true well-test permeability. The problem of nonstationarity between the well-test regions is addressed. The results obtained here show that there is a reduction of reservoir uncertainty when well-test information is added.

A thermodynamic model has been developed for the phase behavior of micellar systems containing up to three amphiphilic species. This model has been tested against experimental data using chemicals typical of those used in surfactant flooding. A fairly good match of static phase behavior experiments has been obtained. The model has been implemented in a compositional simulator and found to be both simple enough and accurate enough for practical reservoir engineering calculations. One important design is to study the separation of the chemicals as they transport through the reservoir. This ty