شهریار عصفوری

Near wellbore condensate blockage phenomena commonly reduce gas production significantly. One efficient method for overcoming such problem is wettability alteration. In this thesis, the field and laboratory performance of wettability alteration on restoring the production rate of the well will be discussed. Before that, the empirical and theoretical correlations for estimating relative permeability in two phase systems, as a key parameter in the process of altering the wettability of gas condensate reservoirs, are evaluated. By understanding these correlations accurately and determine their weaknesses, try to improve them and develop new empirical correlations for estimating the relative permeability of two-phase systems of gas - oil using intelligent systems and multi-gene genetic algorithm. New correlations are evaluated by using the extracted experimental data from the open literature. Their validity is assessed by analyzing errors. The results indicate high accuracy and applicability of new correlations in estimating relative permeability of gas- oil system for different rock and fluids. Then, a field study of wettability alteration process and its effect on enhancing the performance of a well located in super-giant gas condensate field in southern Iran, will be discussed. For this purpose, a simulation of a single well and compositional model by using real rock and fluid data of studied reservoir, is utilized. The effect of involving parameters including the wettability state, treatment radius and time on efficiency of this process are assessed and the optimum conditions for each of these parameters are determined. Results indicate that near-wellbore wettability alteration leads to lower critical condensate saturation which has a significant impact on improving production parameters and reservoir recovery factors. Also, the highest recovery factor is achieved at optimal conditions where wettability is altered from strong liquid-wet to intermediate-wet at the sm