Study on Comprehensive Discrimination Method of Fluid Phase Behavior in Low-Permeability Reservoir for Blood Flow Modelling

摘要

Taking the low-permeability reservoir of complex sandy conglomerate reservoir of Kongdian Formation in Bozhong structure as the research goal, the comprehensive discrimination method of fluid phase state category of low-permeability reservoir is studied. This article analyzes the division method, genesis, and geological characteristics of low-permeability reservoirs and the distribution law of fluid phase. Based on the gas state equation and gasliquid phase equilibrium equation, combined with thermodynamic theory, hydrocarbon fluid phase simulation is carried out by calculating bubble point pressure, dew point pressure, and other parameters. Combining the analysis results of fluid composition of typical wells, the fluid types of low-permeability reservoirs in complex glutenite reservoirs of Kongdian Formation in Bozhong structure are comprehensively distinguished by using phase diagram discrimination method and empirical statistical method of hydrocarbon composition combination parameters. The results show that the phase diagram discrimination method is consistent with the empirical statistical method of hydrocarbon composition combination parameters, and the discrimination accuracy of phase state category is close to 100 %. It is concluded that the low-permeability reservoir of complex sandy conglomerate reservoir of Kongdian Formation in Bozhong structure is mainly oil-free condensate gas reservoir.