Study On The Calibration Method Of Recoverable Reserves Of Gas Injection Condensate Gas Reservoir In Yaha

Condensate gas reservoir that developed by cyclic gas injection is usually make the gas reservoir itself back into the gas zone after the condensate recoveried and processed.For condensate gas reservoir, gas injection is mainly to keep formation pressure, avoide the pressure drop, reduce the amount of condensate recovery. YaHa condensate gas reservoir is in tarim basin, the author of this paper several recoverable reserves evaluation difference is very big, the effect is not ideal situation, developed a set of relatively complete, system of condensate gas reservoir recoverable reserves calibration method.In this paper, based on the research of condensate gas reservoir,mainly using the theory of modern reservoir engineering technology, the integrated use of gas reservoir engineering, well test analysis theory and method, number and combination YaHa static data and dynamic production characteristics of condensate gas reservoir, mainly in the following aspects of research:(1)For YaHa cycle calculation of reserves of condensate gas reservoir, gas injection pressure drop in the conventional material balance equation form reserves into action to verify, due to the effect of pressure of the reinjection of dry gas, when not to consider the influence of injection-production ratio, the calculation of reserves slants big, only considered in the equation of reinjection ratio, to get the right result.(2)Use of nonlinear material balance method, can accurately get the reserves of gas reservoir, gas reservoir water invasion dynamic and correct analysis. The method is suitable for stand-up Wells or several Wells with single pressure system of the dynamic reserves calculation, regardless of how strong water invasion, can through the analysis of the material balance equation, the objective function was established based on data of formation pressure, using the least squares fitting, get the right result.(3)For YaHa this characteristic of condensate gas reservoir cyclic gas injection development, the use of condensate oil content and the total actual production data, the amount of gas condensate very careful analysis and in-depth study of condensate oil content logarithmically with the decline of the accumulative amount of gas condensate to form a typical slow increasing curve.Refer to this new way of thinking, the use of YaHa condensate gas reservoir in the actual production data statistics and analysis, finally got a new relationship:the reduction of the delta of the condensate oil content logarithmically with the total amount of gas condensate Np in semilog coordinate shows a typical slow increasing curve, or use of this relationship, a careful analysis and in-depth research, finally get a kind of effective method to determine the recoverable reserves, the law of diminishing condensate oil content.