Project Job Ref.

REHABILITATION AND UPGRADE OF

STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 1/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE

Design Parameters:
Water Liquid Temperature: 200C
Kinematic Viscosity = 1.007cSt = 1.004 x 10-6m2s-1
Dynamic Viscosity = 1.004 x 10-3m2s-1
Liquid density = 1000kg/m3
Superficial velocity, v = 3.5m/s
Pipe Internal Diameter = 150mm
Hydraulic radius, Dh = D/4 = 150/4 = 37.5mm
Number of elbows = 25 Number of valves =3

References:

1. Perry, R.H., and Green, D.W., “Perry’s Chemical Engineers’ Handbook”, 8th Ed, McGraw - Hill, New
York, NY, p. 6 - 18 (2007).
2. Moran, S., “An Applied Guide to process and plant Design” Butterworth - Heinemann Oxford, UK (2015)
Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 2/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE
Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 3/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE
Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 4/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE
 Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 5/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE

Frictional Losses Through Fittings:

For a 900 elbow, k value can be taken as 0.75

For a Gate valve (1/4 open), k can be taken as 24
Total k = 25 x 0.75 + 3 x 24 = 90.75
Head loss due to fittings,
hf = kv2/2g
= 90.75 x 3.5 2/ (2 x9.81) = 57mwg
Straight Run Head Losses
Colebrook-white approximation can be used to estimate the Darcy friction factor from Reynolds number
greater than 4000

Reynold’s Number,

Re =1000 x 3.5 x 0.15/1.004 x 10-3= 527 000

The below curve fitting equation can be used alternatively in lieu of Colebrook-White equation

Pipe roughness, e for commercial or welded steel can be taken as 0.045mm Relative roughness,
Ꜫ=e/D = 0.045/150 = 0.0003
fD= (-1.8log [(0.0003/3.7)1.11 + 6.9/527000])-2
= (-1.8log [2.877 x 10-5 + 1.309 x 10-5]-2)
= (-1.8log (4.186 x 10-5))-2 = 0.016
The Darcy-Welsbach equation can be used to determine the hydraulic (head loss) due to viscous effects
 Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 6/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE

hL= fDLv2/D(2g)
The pressure loss due to viscous effects is computed using Microsoft excel and is presented in table 2
Table 2: Computation of friction losses due to viscous effects

Friction
Length, factor, g Velocity Diameter, D(2g
2 2
Section L (m) fD (m/s ) , v (m/s) v D(m) ) hL
1 to 2 0.8 0.016 9.81 3.5 12.25 0.15 2.943 0.05327897
2 to 3 16 0.016 9.81 3.5 12.25 0.15 2.943 1.06557934
3 to 4 0.8 0.016 9.81 3.5 12.25 0.15 2.943 0.05327897
4 to 5 27.5 0.016 9.81 3.5 12.25 0.15 2.943 1.83146449
5 to6 2.5 0.016 9.81 3.5 12.25 0.15 2.943 0.16649677
6 to 7 2.2 0.016 9.81 3.5 12.25 0.15 2.943 0.14651716
7 to 8 14 0.016 9.81 3.5 12.25 0.15 2.943 0.93238192
8 to 9 59 0.016 9.81 3.5 12.25 0.15 2.943 3.92932382
9 to 10 7 0.016 9.81 3.5 12.25 0.15 2.943 0.46619096
10 to 11 1.2 0.016 9.81 3.5 12.25 0.15 2.943 0.07991845
11 to 12 112.3 0.016 9.81 3.5 12.25 0.15 2.943 7.479035
12 to 13 1.9 0.016 9.81 3.5 12.25 0.15 2.943 0.12653755
13 to 14 2.5 0.016 9.81 3.5 12.25 0.15 2.943 0.16649677
14 to 15 14.1 0.016 9.81 3.5 12.25 0.15 2.943 0.93904179
15 to 16 2 0.016 9.81 3.5 12.25 0.15 2.943 0.13319742
16 to 17 1.6 0.016 9.81 3.5 12.25 0.15 2.943 0.10655793
17 to 18 120.6 0.016 9.81 3.5 12.25 0.15 2.943 8.03180428
18 to 19 2.2 0.016 9.81 3.5 12.25 0.15 2.943 0.14651716
19 to 20 2.2 0.016 9.81 3.5 12.25 0.15 2.943 0.14651716
20 to 21 2.2 0.016 9.81 3.5 12.25 0.15 2.943 0.14651716
21 to 22 15.1 0.016 9.81 3.5 12.25 0.15 2.943 1.0056405
22 to 23 2.2 0.016 9.81 3.5 12.25 0.15 2.943 0.14651716
23 to 24 1.4 0.016 9.81 3.5 12.25 0.15 2.943 0.09323819
24 to 25 113.5 0.016 9.81 3.5 12.25 0.15 2.943 7.55895345
25 to Foot 4 0.016 9.81 3.5 12.25 0.15 2.943 0.26639484
Total pressure loss due to viscous effects = 35.22
Total head required to be generated by pump = 57 +35.22 = 92mwg
 Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 7/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE

Suction Head and Net Positive pressure head

The Antoine equation may be expressed as:

Where Pv is vapour pressure of the liquid at the pump inlet

T is the temperature and A,B and C are coefficients that can be obtained from the NIST database
(http://webbook.nist.gov)
For water at 300C,
A=5.40221
B= 1838.675
C= -31.737
Log Pv = 5.40221 – 1838.675/ (-31.737 + 303) = -1.376
Pv = 0.0421 bar = 4200 Pa The Net Positive Suction Head,

Where, Pv is as previously defined

P0 is the absolute pressure at the suction reservoir = ρgh = 1000 x 9.81 x 4 = 39240Pa
h0 is the reservoir liquid level relative to the pump centre-line, say 2.5m
and hsf is the head loss due to friction on the suction side of the pump =3.5mwg (est.)
NPSH = 39240 / (1000 x 9.81) + 2.5 – 3.5 - 4200/(1000x9.81) = 2.57bar = 3.27mwg

Determining Pump Power

Where, P = Pump power (Kw)

Q= flow rate (m3/hr) = 3.5 x 3.142 x 0.152 x0.25 = 0.06186m3/s = 223m3/hr
H = total Pump head
 Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 8/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE

ᶯ = pump efficiency, taken as 0.7 if unknown

P = 227 x 1000 x 9.81 x 92/ (3.6 x 106 x 0.7) = 81kW
Summary of Results
Minimum Required head = 92m
Net Positive Suction Head(NPSH) =3.27m
Minimum flow rate = 223m3/hr
Minimum Pump Power = 81kW
Minimum Pump Efficiency = 70%
Recommendation
The existing pump having the following basic specifications (see figure 2) as supplied by the contractor
would be sufficient for the purpose of water abstraction from the lagoon.

Pump Type =Double Suction Split Case

Number of Pumps= 1
Capacity = 227m3/hr > 223m3/hr (Satisfactory)
Head = 120m > 92m (Satisfactory)
Rated Power = 120kW > 81kW (Satisfactory)
NPSH = 3.33 > 3.27 (Satisfactory)
Project Job Ref.
REHABILITATION AND UPGRADE OF
STALLIONAIRE TANK FARM DEPOT FACILITY
Section Sheet no./rev.
PUMP SELECTION ANALYSIS 9/03
Calc. by Date Chk'd by Date App'd by Date
FIO 2-Jun-20 BDE 3-Jun-20 BDE