Application of Blasingame’s Modern Production-Decline Analysis Method in Production Performance Analysis of Buried Hill Condensate Gas Reservoir

With the increase in exploration in recent years, buried hill condensate gas reservoirs have gradually become an important field for increasing reserves and production of offshore oil and gas in China, and efficient development of condensate gas reservoirs has also become a hot issue in hydrocarbon development. Due to the complex phase-change law and retrograde condensation phenomenon of deep condensate gas reservoirs, the reservoir properties and production dynamics data obtained by conventional pressure-recovery-test methods were greatly limited, and the dynamic data and evaluation parameters of the single well control area cannot be accurately determined. In this paper, using the production analysis method to analyze the production dynamics data of a single well, combined with static geological data and well-test analysis data, the reservoir parameters of a single well were evaluated. Specifically, the Blasingame method was applied to realize the production-decline law of production wells, and new dimensionless flow, pressure parameters, and pseudo-time functions were introduced. Using the unstable well test theory and the traditional production decline analysis technology, the IHS Harmony software is used to fit the production dynamic data with the theoretical chart. The evaluation parameters such as reservoir permeability, skin factor, well control radius, and well control reserves were calculated, providing strong support for the production decision-making of the petroleum industry and also providing a strong decision-making basis for the dynamic adjustment of oil–gas-well manufacture.