Performance Characteristics of a Volumetric Condensate Reservoir

Abstract

Abstract The performance history of a volumetric gas condensate reservoir ispresented. Curves depict the pressure-production relation and illustrate thephase behavior of the reservoir fluid. This performance is compared tocalculated performance. This Bacon Lime Reservoir was discovered in 1941 and has been produced tofield separators and gas sales. Reservoir performance has been observed byperiodic bottom hole pressure surveys and companion sample analysis of welleffluents, in addition to gas and condensate production data. The pressure-production history demonstrates that the reservoir has producedunder volumetric control. The "retrograde" behavior of the reservoirfluid is illustrated by decreasing butanes-plus content of the well effluent, followed by revaporization as the reservoir pressure approaches abandonment.Calculated performance predictions are compared to actual performance and somediscussion offered on apparent discrepancies. Introduction Since the late 1930's, many gas condensate reservoirs have been developed, the retrograde theory of phase behavior has been generally accepted, and anumber of cycling programs have been initiated. Numerous technical papers havesince appeared in the literature dealing with the theory and application ofcycling the gas condensate reservoirs. Some cycling operations have nowadvanced to a stage where it is possible to determine performancecharacteristics to a fair degree of accuracy. Field performance data for gas condensate reservoirs operated by pressuredepletion have not been so extensively reported in the literature, althoughtheir probable behavior has been discussed in explanation of the retrogradetheory. It is the purpose of this paper to compare calculated theoreticalreservoir performance with field observations and well stream analyses whichhave been obtained throughout the practical producing life of a smallvolumetric gas condensate reservoir. The reservoir under study is the Bacon Lime Zone of a field located in EastTexas. The Bacon Lime occurs in the Lower Glen Rose Formation of CretaceousAge. T.P. 2708