Say one has a volumetric dry gas reservoir with initial/final pressures & z-factors of 4,800/1,500 psia & 0.98/0.90. Pretty standard numbers. What's the recovery factor?
The Guidebook 13 RES 1 & 2 covers dry gas. Since recovery is just Gp/G, it's easy to move the numbers around from the given equations. One way to do this is by finding the difference between the P/z for initial and final conditions and dividing by P/z initial. In this case, it's just (4,900 - 1,700)/4,900 or 65%.
Be careful not to confuse the z-factor with FVF. If given initial and final FVF the problem is much easier as the Guidebook shows: 1-(Bgi/Bgf). It's common to confuse the two numbers because they often look alike.
The Guidebook 13 RES 1 & 2 covers dry gas. Since recovery is just Gp/G, it's easy to move the numbers around from the given equations. One way to do this is by finding the difference between the P/z for initial and final conditions and dividing by P/z initial. In this case, it's just (4,900 - 1,700)/4,900 or 65%.
Be careful not to confuse the z-factor with FVF. If given initial and final FVF the problem is much easier as the Guidebook shows: 1-(Bgi/Bgf). It's common to confuse the two numbers because they often look alike.
I ended up finding Bgi and Bga using the z factors. then 1-(Bgi/Bga). Work the same?
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