Guo Jianlin
Research Institute of Petroleum Exploration and Development, China
Title: Recovery rate calculation method of large tight sandstone gas field
Biography
Biography: Guo Jianlin
Abstract
Large tight sandstone gas field are characterized with big gas bearing area, poor reservoir property, strong heterogeneity and enormous scale of reserves and production. For tight sandstone gas field, recovery rate and the ultimate production are the key indicators to guide long-term stable development, make development technical strategies and evaluate the development effect. Due to its small pore & throat and complex seepage mechanism, tight sand gas is difficult to obtain accurate recovery data by conventional laboratory simulation methods. Taking Sulige large tight sandstone gas field as the research object, typical blocks are selected from the central, east, west, south zone to carry out detailed anatomy, and production wells are classified into three types according to the geological characteristics and development effect. The area ratios of various wells zones are restricted by sedimentary facies distribution. Choosing a large number of wells with long production history and in the quasi-steady-state for analysis samples, using rate transient analysis and production curvilinear integral methods, the dynamic reserves and the ultimate production are evaluated for each type of well. Integrating reservoir scale, structure and production dynamic characteristics, single well’s control scope is determined. The technical limited production, producing reserves and recovery rate are simulated considering the well pattern would be infilled with a high density. The research result shows that the technical limited recovery rate of the gas field is 71.2~ 78.5%, average 75.3%, while that of conventional gas reservoirs is 80~90%. The gas field has a technical limited production of 1.96 trillion square meters, and the current economic limited production is 1.17 trillion square meters. In the future, with the technology improvement and the development cost reduction, the production of gas field will increase by 0.79 trillion square meters.