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INDEX"Three Phase (Gas - Oil - Water) Horizontal Separator: As per ""Petroleu

m and Gas Field Processing - Hussein K. Abdel-Aal, Mohamed Aggour, M. A. Fahim"""

INPUT PARAMETERSQg 8 mmscfd Gas rate

Yellow boxes are input boxes. SCHEMATICQo 8000 bbl/d Oil rateQw 3000 bbl/d Water rate?'o 27.5 oAPI Oil density?o 0.89 Oil specific gravityµo 20 cP Oil viscosity?w 1.04 Water specific gravity? 0.65 Gas specific gravityZ 0.89 Gas compressibilityP 250 psia Operating pressureT' 95 oF Operating temperatureT 555 oR Operating temperaturetw 10 minutes Water retention time (Refer Table 2)to 15 minutes Oil retention time (Refer Table 2)µg 0.013 cP Gas viscosity

"dm,w" 500 Micron Smallest water droplet size to be removed"dm,o" 100 Micron Smallest oil droplet size to be removedNLL 50% Normal liquid level due to oil and water

CALCULATIONSEQUATIONS

Step 1: Determine gas and oil properties?g 0.89 lb/ft3 Gas operating density?o 55.5 lb/ft3 Oil operating density

Step 2: Determine CdCd 2.07 Assume Drag coefficientu 0.65 ft/s Settling velocity of oil droplet

Re 22 Reynolds no.Cd 2.09Error 0.00 "Use goal seek to get error zero, by changing as

ssumed Cd"

Step 3: Determine minimum diameter for water droplet settling"Ho,max" 36.0 inAw / A 0.10 Ao + Aw = NLL * AHo / D 0.315 AssumeAw / A 0.13Error 0.00 "Use goal seek to get error zero, by changing as

ssumed Ho/D"Dmax 114 in Maximum allowable vessel diameter

Step 4: Check for gas capacity constraintDL 122 in.ft

Step 4: Check for liquid capacity constraintD2L 214350 in2ft

Try different combinations of D (smaller than Dmax).TABLE 1"D, in" "L (gas), ft" "Ls (gas)= L + D/12, ft" "L, ft" "Ls (liq

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uid)= 4 L/3, ft" Governing case SR = L / (D/12)12 10.2 11.2 1488.5 1984.7 Liquid Capacity 1984.7

TABLE 2 (Ref. API 12J)24 5.1 7.1 372.1 496.2 Liquid Capacity 248.1

Oil Gravities "Retention time, minutes (Typical)"30 4.1 6.6 238.2 317.6 Liquid Capacity 127.0

Above 35 oAPI 3 to 536 3.4 6.4 165.4 220.5 Liquid Capacity 73.5

Below 35 oAPI66 1.9 7.4 49.2 65.6 Liquid Capacity 11.9

100+ oF 5 to 1072 1.7 7.7 41.3 55.1 Liquid Capacity 9.2

80+ oF 10 to 2078 1.6 8.1 35.2 47.0 Liquid Capacity 7.2

60+ oF 20 to 3084 1.5 8.5 30.4 40.5 Liquid Capacity 5.890 1.4 8.9 26.5 35.3 Liquid Capacity 4.796 1.3 9.3 23.3 31.0 Liquid Capacity 3.9102 1.2 9.7 20.6 27.5 Liquid Capacity 3.2

Ls 35.3 ft Seam to seam length (select from Table 1)SR 4.7 Slenderness ratio (typical value 3 to 5) (selec

t from Table 1)D 90.0 in Separator diameter (select from Table 1)

L 26.5 ft "Effective length ofthe separator"Qg 156 mmscfd Calculated gas capacity for selected L & D (Shou

ld be more than 8 MMSCFD - input value)

NOTES"1. As per GPSA, typical horizontal L/D ratios are normally in the 2.5 t

o 5 range."