Table 2 shows the fluid composition of the surface recombined fluid sample

Table 2 shows the fluid composition of the surface

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respectively. Table 2 shows the fluid composition of the surface recombined fluid sample. Table 2. GT9 and GT12 fluids compositions. GT9 GT12 Component Mole% Mole% Wt. Fraction% N 2 0.06 1.02 0.42973 CO 2 3.72 1.84 1.1397 H 2 S 0 0 0 C1 78.89 53.46 12.07 C2 5.93 5.86 2.4799 C3 3.61 4.81 2.9851 iC4 0.83 1.27 1.0389 nC4 1.29 2.52 2.0614 iC5 0.57 1.23 1.249 nC5 0.49 1.52 0.91388 C6 0.67 0.9 1.1397 C7+ 3.94 25.5 73.835
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136 Okotie Sylvester et al. : PVT Analysis Reports of Akpet GT9 and GT12 Reservoirs 10. Results The PVT analysis for Akpet GT9 and GT12 reservoirs was carried out. This is in line with fitting an EOS to the laboratory PVT experimental data and then using the Equation of State to produce ECLIPSE black oil PVT tables and EOS model for use in dynamic modeling of the Akpet reservoir dynamic simulation. Analysis of GT9 Results Gas condensate systems are known to exhibit mass transfer and compositional changes on pressure depletion. Hence, the mathematical formulation of a Compositional Simulator is such that for each time –step, the system composition is determined for each grid block. It is therefore necessary to further reduce the 12 components to an acceptable minimum to gain computing time. The 12 components was lumped into four (4) and subsequent split of the C6C7 heavy component into 3 pseudo components to give a final six (6) grouped components as shown in Tables 3 & 4. Table 3. Grouped fluid composition. Components Mol% Mol Wt Specific Gravity C1 78.89 C2NC 9.71 35.398 0.63731 C3C5 6.97 52.856 0.58474 C6C7 4.61 123.74 0.76126 Table 4. Final Grouped Composition. Components Mole Fraction% Weight Fraction% Mol Weight Specific Gravity C1 78.89 49.854 C2NC 9.71 13.539 35.98 0.63731 Components Mole Fraction% Weight Fraction% Mol Weight Specific Gravity C3C5 6.79 14.137 52.856 0.58474 FRC1 1.909 5.6442 75.06 0.70387 FRC2 2.0574 10.551 130.2 0.75838 FRC3 0.6435 6.2746 247.48 0.82729 A material balance check was carried out on the CVD experiment using the vapour composition, equilibration ratio - Log (Ki) and the Hoffman – Crump- Hocott plots. This is necessary in order to identify and correct measurement errors and data inconsistencies which manifest as negative liquid moles at some pressure depletion stages of the CVD experiment. An adjustment of the reported moles recovered was made to correct these errors before grouping, splitting and subsequent regression. EoS Modeling The final 6 grouped component is used in modeling fluid sample. The fluid model was defined with the 3-Parameter Peng-Robinson (PR3). This 3-Parameter Peng Robinson (EOS) and Lohrenz-Bray-Clark (LBC) viscosity correlation were used to fit the simulated results to the experimental data. The parameters tuned for the various fluid properties to obtain a match are as follows: (a) Saturation pressure – Omega A (b) Vapour Z factor – Volume Shift (c) Liquid dropout – Pcirt and Tcrit (d) Viscosity – Critical Volume A calculated dew point pressure of 4630.113psia (Lab experimentally determined = 4633 psia) is obtained at the end of tuning. The results and plots from the PVT analysis on the Akpet GT9 reservoir are depicted in Figure 6 to 14.
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  • Winter '14
  • ir. sugiatmo kasmungin
  • PVT Analysis Reports

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