Gas-condensate field Honey is located in the central part of Vojvodina (Panonian basin).Reservoir has high temperature and pressure (366 bar) and consists 80% of CO2. Initialcondensate factor is about 900 m 3 /m 3 . Reserves calculated by volumetric method are OGIP =860 10 6 m 3 , OOIP = 829 10 3 m 3 . Four wells were drilled so far.Field was in production for several months. During this testing period intensive welltestmeasurements were done, including build up, puls test, limit test and separator tests. Welltestinterpretation showed there was good communication between wells, presence of nearwellbore zone damage, rather small permeability (around 10mD and less).An approximate value of reserves got from limit test showed good match with volumetriccalculation. Material balance calculation also showed reserve values in the same range.Laboratory PVT analysis was done at recombining sample, which included primary tests,CCE and CVD tests. It confirmed gas-condensate behavior of fluid near critical point, withdew point pressure, Pdew = 362.8 bar.Main goal of this study was to find optimum field development plan. Full field 10-componentcompositional model of the reservoir was used as a tool for designing it. As the gas from thefield is basically CO2 predominate interest was to reach the highest condensate recovery.Laboratory PVT data were used for compositional simulation. The Peng-Robinson EOS wasapplied to describe fluid behavior. Analysis of laboratory data implied that splitting of plusfraction was necessary. Grouping was done to decrease number of components forcompositional simulation. Tuning EOS model matched CCE and CVD laboratory tests, andgot rather good match. CCE and CVD liquid saturation are shown in Figure 1.Compositional simulation was performed to analyze effects of produced gas injection torecovery efficiency. Because production history is very short, only one well H-1, produced,other wells were tested, matching was done to data got from welltest. Time steps used insimulation are small for production history and welltesting period. Although that greatlyincreased simulation time it has been considered necessary to get better description ofreservoir behavior and more reliable production forecast. History matching of reservoirpressure is shown in Figure 2., bottomhole flowing pressure in Figure 3. Simulation pressureresults are given per each well (each well has different referent depth). Condensate productionhistory matching for well H-1 is shown in Figure 4.Gas-condensate reservoirs are characterized by specific behavior. Pressure drop below dewpoint causes condensate blockage effects in near wellbore zone. Around well H-1, local gridrefinement was done to monitor condensate saturation changes near the well. It could benoticed that condesate saturation increases in nearwellbore zone with pressure decline.
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