3 Phase Separator Spreadsheet [PDF]

Zitiervorschau

EXAMPLE 4: SIZE A 3-PHASE HORIZONTAL SEPARATOR Gas Flowrate (MMSCFD) Oil Flowrate (BOPD) Water Flowrate (BWPD) Total Liquid (BPD) ATM Press. Op Press (psig) Op Temp (F) Gas Compressibility Z Retention Time (min) t Remove drops >__micron from gas Remove H2O drops >__micron from oil Remove oil drops >__micron from H2O Vessel Liquid Level - beta 1. Calculate design specification information rg = (P+Pa)(MW) 10.73*(T+460)*(z) rl = 62.4(sp. gr.) rw = 62.4(sp. Gr H2O.) Dp= 0.00003937(micron)/12 Dw= 0.00003937(micron)/12 Do = 0.00003937(micron)/12 m=MMSCFD(1e6)(MW) 379.4(24)(3600) Qa=m/rg Ql Qw Qm=Qa+Ql+Qw pm=(rl*Ql+rg*Qg+rw*Qw)/Qm Fractional area of liquids - alpha

0.01 60 100 160.00 14.7 50.00 120 0.89 3.00 150 500 200 50%

0.27

lb/cu ft

49.92 62.40 0.000492 0.001640 0.000656 0.01

lb/cu ft lb/cu ft ft ft ft lb/sec

0.03 0.0039 0.0065 0.04 15.97 0.50

2. Calculate C D and min diameter Trial No. Assume CD

23 0.8 1

acfs cu ft/sec cu ft/sec cu ft/sec lb/cu ft

1 2.01

Vt = (4gDp(rl-rg)/3CDrg)^0.5 Re = 1488(DpVtrg)/m

Gas MW Oil S.G. Water S.G.

2 2.02

3 2.02

1.39

1.39

1.39

22.86

22.82

22.81

2.02

2.02

2.02

Calculated CD Minimum dia.= 12*(TZQg/2.4Vt(P+Pa))^0.5 3. Determine the fractional height of water in the vessel Fractional area of water aw=atQw/t(Qw+Ql) 0.313 Fractional height of water bw 0.350 Fractional area of water aw 0.312

4. Calculate max vessel diameter for water settling Vtw = 1488gDw2(pw-pl)/18ml 0.08 Max Height of Oil Pad, Ho 165.04 Maximum diameter = Ho/(b-bw) 1100

1.9 in

6

change until above matches below

ft/sec in max in max

5. Calculate max vessel diameter for oil settling Vtw = 1488gDw2(pw-pl)/18mw Max Height of water, Hw Maximum diameter = Hw/bw Maximum Vessel Diameter

0.0207 44.77 128

ft/sec in max in max

128

126

6. Calculate vessel gas and liquid capacity requirements dvLeff (for gas capacity) 0.30 dv^2*Leff (for liquid capacity) 686 7. Determine appropriate diameter and S-S length Diameter (in) Leff (gas) Lss (gas) Leff (liquid) Lss (liquid) Lss (ft) L/D

24 0.01 2.01 1.19 1.59 3 1.25

30 0.01 2.51 0.76 1.02 3 1.20

36 0.01 3.01 0.53 0.71 4 1.17

Gas Viscosity m Oil Viscosity ml H2O Viscosity mw

4 2.02

in

matches below

0.012 1.17 0.69

cp cp cp

5 2.02

6 2.02

1.39

1.39

1.39

22.81

22.80

22.80

2.02

2.02

2.02

in

42 0.01 3.51 0.39 0.52 4 1.14

48 0.01 4.01 0.30 0.40 5 1.13

54 0.01 4.51 0.24 0.31 5 1.11