年間 4 号発行
ISSN 印刷: 2151-4798
ISSN オンライン: 2151-562X
Indexed in
DETERMINATION OF RECOVERY OF GAS RESERVOIRS WITH LARGE AQUIFERS
要約
Gas recovery (Rg) of gas reservoirs has great significance in determining subsequent development plans and economic benefit. The demarcation method is considered to be applicable to evaluate Rg of water-drive gas reservoirs. This paper will further demonstrate the capability and applicability of the method on large aquifers. First, based on the material balance equation, various types of correlations of normalized pressure (pr) versus Rg are analyzed, which shows the upward trend of theoretical curves in the demarcation method. Second, a rectangular simulation model of a water-drive gas reservoir is built. The influence of aquifer size, types of gas reservoir contacting with aquifers, water productivity index, and gas production rate on the curves of pr versus Rg are analyzed, whose results are consistent with the theoretical analysis. The larger the aquifer size of the gas reservoir is, the more upward trend the curve has, while the opposite is the case with a gas reservoir with small aquifers. Subsequently, four cases with large aquifers are given in this paper. In these cases, the Rg obtained from the method are notably close to the simulation results performed with the Eclipse Office software. It can be concluded that the demarcation method can be applied successfully to determine Rg of gas reservoirs with large aquifers.