Gas lift design assignment

1. ASSIGNMENT– 1: THE UNIVERSAL GASLIFTDESIGN CONCEPT
Givendata:
Desiredproductionrate: 1000bopd (0% BS&W)
DesiredFTHP: 200psi
Total vertical depth: 8500ft
Perforations: 8430ft - 8480ft
CasingSize: 5-1/2”
TubingSize: 2”
Average reservoirpressure: 2200psi
Wellheadtemperature: 140⁰F
Staticgradient: 0.37psi/ft
PI: 0.85bopd/psi
GL injectionpressure: 1000psi
Gas allocation: 500Mscf/d
Load fluid: 0.45psi/ft
PackerDepth: 6800ft
Questions:
1. Giventhe above well condition,generate aPZplot& define the co-ordinates/the midperfs.
2. Plotthe static fluidgradientonPZplot. Show the staticfluidlevelonyourPZplotwhenthe
well isshut-inandshowcalculationstoverifyyourplot.
3. Calculate the initial FBHP
4. If the well isopenedup,plotthe flowingfluidgradient(use closestcurve to0 GLR), will the
well flow?Determine the fluidlevel if the well will notflow.
5. Withthe pressure transientcurvesalreadyprovided,selectthe appropriate curve &trace
the slope.
6. Determine the requiredGLR
7. Is the quantityof gas available sufficientforthe proposeddesignGLR?Show reasons.
8. From the designplot,determinethe new FBHP
9. Giventhe gas gradient,whatisthe pressure atthe topof the packer(withinthe annulus)?
Select factor (F) from the table. For example, 10000 ft and S.G. of 0.65 (F = 0.253). Note
for Pcf (at depth) = Pcf (at surface) ( 1 + F)
10. Designforthe unloadingandoperating gasliftvalves
11. At whatdepthisunloading of the firstunloadingvalve? Whatare theirtransferpoints(psig)
12. At whatdepthisthe operatingvalve?