RO CalculationsCalculation of the Wetted surface Area

Vessel informationOD 3.75 ftL 36 ftT 64P 1160.3 psiz1 0.8325

Lower Portion - CondensateLAHH 3.3 ft

15.2

39.3

54.5

Upper Portion GlycolLAHH 2.5 ft

29.5

Total Surface Area VesselTotal 83.9Total + 20% 100.7

Calculation Of Heat inputQ 880328.06 BTU/hrλ 178 BTU/lbW 4946 lb/hrW 2243 kg/hr

Volume CalculationsCylinder 346.4Heads 11.220% pipe 71.5Total 429.1m1 1723.2 lb

-5.50.9695

100 psi assumes constant volume for Delta Mass166.53214 isolated system at RO open

del mass 1556.7 lb 706.0989 kgtime 15 minrate 103.8 lb/minrate 6226.7 lb/hr

Overall Rate Relief and Vessel Volumerate 11172 lb/hr

5067.7133 kg/hr

oF

Areahead ft2

Arealevel ft2

Arealower ft2

Arealevel ft2

ft2

ft3

ft3

ft3

ft3

T2

z2

P2

m2

RO sizing

Method: Use API 520 Gas critical flow eqn for PRV

Input data 01-380-0-VE-01 01-380-0-VE-01Case LAHH LALL

Fire Wetted Fire WettedW flow rate kg/h 5067.71 5067.71cp/cv 1.177 1.177C coeff based on cp/cv 336 336Kd eff coeff of discharge 0.975 0.975P1 upstream pressure kPaa 7978 7978Kb capacity correction factor due to back pressure 1 1Kc corection factor for rupture disk 1 1T relieving temp K 291 291Z compressibility factor 0.833 0.833M molecular weight 16.00 16.00

Calculated values

A mm2 99.29 99.29d equiv orifice dia mm 11.24 11.24

Selected orifice dia mm 20see "Numerical" for sizing

required effective discharge area= 13160.W/(C.Kd.P1.Kb.Kc).(TZ/M)0.5

Equation

constantsM 16R 8314.5C 0.72k 1.17Pa 200000

1.753234317 3.45 A 0.000314 m2 Orifice size 20

Target Mass to hit 1266.928 kginterval 1.67 min

P kPa Z T (K) degF t mass (kg). cumulativeQi (kg/s) 3.277506 8000000 0.8325 291 1.7 327.75

2.870869 7000000 0.8445 286.3 55.86 3.3 287.09 614.842.464943 6000000 0.855 281.8 47.8 5.0 246.49 861.332.055841 5000000 0.8685 276.9 39.08 6.7 205.58 1066.921.644514 4000000 0.8854 271.7 29.66 8.3 164.45 1231.371.231809 3000000 0.9065 266.1 19.5 10.0 123.18 1354.550.819227 2000000 0.9321 260.0 8.6 11.7 81.92 1436.470.408056 1000000 0.9631 253.6 -3 13.3 40.81 1477.280.281346 690000 0.97 252.1 -5.56 15.0 28.13 1505.410.203549 500000 0.9808 250.2 -9.125 16.666666667 20.35

1505.41

Hourly Rate 6022 kg/hr

PROJECT : OYO FPSO

JOB NO : 2008-07

LOCATION : Nigeria

CLIENT : BA / ENI

REFERENCES : 1. ISOTHERMAL FLOW - API 521, 4TH EDITION, MARCH 1997, SECTION 5.42. FITTINGS K FACTOR - FLOW OF FLUIDS THROUGH VALVES, FITTINGS AND PIPE, CRANE3. FRICTION FACTORS - HSI-JEN CHEN EQUATION "SOLVING FLUID FLOW PROBLEMS WITH SPREADSHEETS", HYDROCARBON PROCESSING, SEPTEMBER 1989.

GENERAL DATA

Line number

PFD stream number

Fluid HC gas

Case

PROCESS INPUT DATA

Mass flowrate (kg/hr) 6021.644

Temperature (deg C) 17.85

Pipe outlet pressure (bar abs) 2.01

Molecular weight 20

Compressibility factor Z 0.8325

Specific heat ratio 1.177

Fluid viscosity (cP) 0.013172

PIPE SIZE DATA

Pipe schedule 80

Pipe nominal diameter (in) 4"

Pipe OD (mm) 114.3

Pipe ID no. 10

Pipe thickness (mm) 8.56

Pipe internal diameter (mm) 97.18

Absolute roughness (mm) 0.045

PIPE & FITTINGS

Pipe straight length (m) 5.3

Fittings (K factors)

Globe valve Stem perpendicular to run

Y-pattern

Angle valve

Gate valve Wedge disc, double disc, plug

Check valve Conventional swing

ISOTHERMAL COMPRESSIBLE FLOW PRESSURE DROP CALCULATION SHEET

From d/s RO-4302(1)

ToHP Flare

Header (2)

Fire wetted

depresur.

Lift check valve

Footvalve Poppet disc w/ strainer

Ball valve Full bore 1 0.050

Reduced bore <= 1 1/2"

Reduced bore > 1 1/2"

Butterfly valve 2" to 8"

10" to 14"

16" to 24"

Plug valve Straight thru'

90° Elbow welded/flange, 1.5D

welded/flange, 3D 3 0.603

screwed, std

45° Elbow

Tee Flow thru run 3 1.005

Flow thru branch

Reducer Enlargement

Contraction

Pipe entrance 1 0.780

Pipe exit 1 1.000

Others

Total K factors for fittings 3.437558

Total equivalent length for fittings (m) 19.95232

Total equivalent length for pipe & fittings (m) 25.25232

OUTPUT

Pipe outlet fluid density (kg/m3) 1.9959

Pipe inlet fluid density (kg/m3) 2.418702

Average fluid density (kg/m3) 2.207301

Type of flow subsonic

Mach number at pipe outlet 0.328347

Reynold number 1675560

Friction factor 0.016743

(kg/m.s2) 25846.91

Flow regime Turbulent

(bar) Err:522

Pipe inlet pressure (bar abs) Err:522

Pipe outlet pressure (bar abs) 2.01

Pipe outlet volumetric flowrate (m3/hr) 3017.007

Pipe outlet average velocity (m/sec) 113.7981

Reynolds number 1675560

Friction factor constant A 0.000125

Friction factor constant B 3E-06

1/f^0.5 7.728286

Friction factor 0.016743

Mass flowrate (lb/hr) 13277.73

rv2

DP

Temperature (deg F) 64.13

(Rankine) 524.13

Pipe outlet pressure (psi a) 29.1497

Critical pressure (psi a) 9.571623

Corrected pipe outlet pressure (psi a) 29.1497

Molecular weight 20

Compressibility factor Z 0.8325

Specific heat ratio 1.177

Fluid viscosity (cP) 0.013172

Pipe internal diameter (inch) 3.825984

(feet) 0.318832

Flow type subsonic

Mach number at pipe outlet 0.328347

Corrected Mach number at pipe outlet 0.328347

Pipe equivalent length (feet) 82.8276

fL/D 4.349575

Per API 521

Pipe inlet pressure P1 (psi abs) 35.32944

P1' 29.1507

P1' ERR 1

P1' n+1 35.32944

y 4.349643

ISERROR(81) 1

Pipe inlet pressure (bar abs) 2.435789

REV 0DATE 11/25/2008BY LYLCHECKED KKP

1. ISOTHERMAL FLOW - API 521, 4TH EDITION, MARCH 1997, SECTION 5.42. FITTINGS K FACTOR - FLOW OF FLUIDS THROUGH VALVES, FITTINGS AND PIPE, CRANE3. FRICTION FACTORS - HSI-JEN CHEN EQUATION "SOLVING FLUID FLOW PROBLEMS WITH SPREADSHEETS",

VE-01 (3)

HC gas

6021.644

17.85

80.8

20

0.8325

1.177

0.013172

80

2"

60.3

10

5.54

49.22

0.045

1

ISOTHERMAL COMPRESSIBLE FLOW PRESSURE DROP CALCULATION SHEET VER. 1.03 (June 2004)

u/s RO-4302(4)

Fire wetted

depresur.

1 0.058

3 1.159

1 0.780

1 1.000

2.996872

7.636693

8.636693

80.2332

80.37054

80.30187

subsonic

0.031846

3308227

0.019315

9770.898

Turbulent

Err:522

Err:522

80.8

75.05178

11.03545

3308227

0.000247

1.52E-06

7.195281

0.019315

13277.73

64.13

524.13

1171.605

37.31266

1171.605

20 0 0 0

0.8325 0 0 0

1.177 0 0 0

0.013172 0 0 0

1.937795

0.161483

subsonic

0.031846

0.031846

28.32835

3.388435

1173.616

1171.606

1

1173.616

3.388437

1 0 0 0

80.93832

SummaryFlow rates

From vessel volume 2824 kg/hrFrom fire relief 2243 kg/hrtotal 5068 kg/hr

Mass needed to evacuate in 15 min1267 kg

Orrifice sized for RV fire case11.24 mm

Orrifice sized using Numerical methodSelected 20 mm

Flow rate in the 15 min duration 6022 kg/hr

Line SizingInlet

size 2"DP Err:522 barMach 0.032Velocity 11.04 m/s

Outletsize 4"DP Err:522 barMach 0.33Velocity 113.80 m/s