Introduction

to
Storge Tanks Engineering
By: Mohamed Ebeid

Date May 11th, 2009

Index
Part 1 Introduction
Part 2 Atmospheric Storage
Part 3 Pressurized Storage
Part 4 Refrigerated Storage
Part 5 Tank Main Components
Part 6 Design & Construction

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

PART 1
Introduction

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

What is a Storage Tank?

Liquid

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Gas

Why is a Tank potentially hazardous?

HUGE QUANTITIES OF FLAMMABLE/TOXIC FLUIDS

FIRE/EXPLOSION/POLLUTION
LOSS OF HUMAN LIFE
& ENVIRONMENTAL / ECONOMICAL LOSSES

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Failure
U can never suppress it . Just wait till all the oil will be burnt and make sure other tanks
will not be in fire

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

How to assure Mechanical Integrity of Tank?

System Selection

Extensive Analysis

Design

Recognized Standard

Fabrication

Qualified Fabricator

Tests and Inspections

Recognized Inspector

Tank is not an Equipment, but a System. System selection is the selection of storage
philosophy, roof type, Material and degree of protection required Containment Classification.

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Storage Philosophy
C
120

Barg
200

AMB
60

20

-10

-20

0.5
-50
0.2
-120

0.05
ATM

-168

-0.05
-0.2

NTS

F.V.
NTS

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Liqui
d

Storage Tanks Classification

Fluid

Liqui
d

Gas
Storage Conditions
ATM

+P

AMB

-T

+P
-T

Construction
Flat
Bottom
M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Sphere

Bullet

PART 2
Atmospheric Storage

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Fixed Roof
Cone / Dome

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Floating Roof
Internal

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Floating Roof
External

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Pan Floating Roof

<20m

Its is the simplest form of floating roof, it is merely a large, flat pan ,slightly smaller in diameter than the inside of the tank shell. It is
provided with a system of flexible shoes to close the space between the edge of the roof and the tank shell.
M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Pontoon Floating Roof

<50m

The floating roof is built from a series of pontoons, or closed compartments, around its outer edge to increase floating stability and
to simplify the structure
M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Double Deck Floating Roof

>50m

The double-deck type employs two separate decks of steel plate over the entire tank area. The space between the upper and
lower plates is divided into compartments. With this type of roof the oil is never in contact with the underside of a plate whose top
surface is directly exposed to the suns rays.
M. Ebeid - Introduction to Storage Tanks Engineering May 2009

PART 3
Pressurized Storage

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Plain Hemispheroid

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Noded Hemispheroid

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Plain Spheroidal

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Noded Spheroidal

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

PART 4
Refrigerated Storage

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Gases & Materials

Gas

Storage Temp.
(C)

Material of Construction

(parts in contact with stored medium)

VCM
Butane
Ammonia/Chlorine

0
-10
-33

KCS A516-XX

Propane
Propylene
Carbon Dioxide

-42
-47
-51

LTCS A 537 Gr. 1/2

A 737 Gr. B

Ethane
Ethylene

-90
-103

5%Ni A645

Methane (LNG)

-162

9%Ni A553

Oxygen
Argon
Nitrogen
Hydrogen
Helium

-183
-186
-196
-253
-268

Al.
SS

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Alloys 5052 / 5086 / 5083

A240-304 / 304L

Single Containment
Al. Jacket
Outer Tank

Only Inner Shell is designed and constructed to contain

the refrigerated liquid.
Any additional external Tank is primarily for the retention
and protection of insulation and to constrain the vapor
purge gas pressure, but is not designed to contain
refrigerated liquid in the event of leakage from the inner
Shell.

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Definition as per BS7777

Double Containment

Outer Tank

Outer Wall
(2nd Container)

Both Inner Shell and Outer Wall are independently

capable to contain the refrigerated liquid.
But, Outer Wall is not capable to contain any vapor
resulting from product leakage from the inner Shell

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Definition as per BS7777

Full Containment

Outer Tank
(2ndContainer)

Both Inner Shell & Outer Tank are capable to contain

the LNG without other support.
Outer Tank is capable to withstands External loadings.
The option of concrete wall is capable of withstanding
higher external emergency loadings than an outer steel
tank (increase of safety)
The concrete roof increases the safety again. It is less
susceptible to damage from external forces and has better
fire resistance properties

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Definition as per BS7777

Full Containment Tank Components

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

5. RC
7.
8.
9.
12.
10.
3.
4.
6.
11.
1.
2.
Roof
PC
Suspended
Inner
RC
Roof
RC
Side
Suspension
Second
Piles
Side
Roof
Liner
Bottom
Shell
Insulation
Liner
Insulation
Wall
Barrier
Deck
AAPiles
Slab
A
PC
steel
Rod
concrete
9%Ni
steel
Between
Aluminum
concrete
Perlite
Insupport
roof
Stainless
RC
the
steel
side
liner
roof
very
concrete
powder
the
liner
inner
wall
the
alloy
ishas
rare
inner
tank
installed
is
steel
tank
suspended
a
installed
the
or
case
structure
shell
bottom
LNG-tight
glass
advantage
is
suspension
on
of
an
and
on
inner
the
slab
open
wool
deck
outer
design
the
inside
tank
of
with
inside
top
is
supports
side
rods
protection
and
face
used
leakage,
structure
piles
wall
face
monolithic
hang
offor
the
the
isis
offilled
LNG
from
roof
and
RC
the
heat
roof
PC
holds
connections
to
from
side
foundation
with
will
insulation
insulation.
keep
LNG
suspended
accumulate
perlite
wall
adjacent
natural
into
are
it.of
powder
to
keep
made
the
maintain
gas
fires
deck
inside
natural
tank.
vapor
to
between
and
from
make
the
ofgas
inside.
from
the
the
inside
side
vapor
wall
9%Ni
roof
the
insulation.
temperature.
and
structure.
inside.
impact
steel
roof,
secondary
wall
of flying
and
objects.
bottom.
barrier.

Tank Loadings
Single
Containment

Double
Containment

Full
Containment

Single
Steel Tank

Double
Steel Tank

Single
Steel Tank

Double
Steel Tank

Single
Tank

Double
Tank

S
S

S
T

S, W
S

S, T
T

N.A

S,T
T

S
S
S
S
S
S
S

S
S,T
T
S,T
T
T
T

S,W
S
S
S
S
S
S

S,W
S,T
T
S,T,W
T,W
T
T

TANK PARTS THAT

CAN CONTAINS
Liquid
Evaporated Gas
WITHSTANDS
Liquid Static Head
Gas Pressure
Roof
Seismic
Wind
Piping Loading
Other Ext. Loads

N.A.

S,T
T , (S)
T
S,T
T
T
T

S : Inner Shell
T : Outer Tank
W : Outer Wall
M. Ebeid - Introduction to Storage Tanks Engineering May 2009

N.B.: this table shall be considered only as an Explanatory guidance; applied standard shall for used for
real loadings.

PART 5
Tank Main Components

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Components
Open Vent
Gauge Hatch

Roof Leg

(Goose Neck)

Guide Pole

Pontoon
M. H.

Rim
Vent

(Level Gauge)

Still Column

Seal

Roof
Drain
Clean Out
Door
Draw Off
Sump

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

PART 6
Design & Construction

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Standards

API 650
API 620
API 12F
BS 7777
EN-14015

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

SHEET

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Bottom
1:100

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Shell

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Roof

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

LNG Tank Construction

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Placing concrete of the bottom slab

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Bottom heater piping work

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

PC Wall Work & Roof Structure

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Lifting by Air-raising & Fixing Roof Structure

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Concrete Roof work

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Welding of concrete liner Plates

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Bottom Insulation

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Inner Tank Work

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

9% nickel Inner Tank & Pump Stand Pipe

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

LNG Tank Analysis

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

Holding-down Strap

M. Ebeid - Introduction to Storage Tanks Engineering May 2009

M. Ebeid - Introduction to Storage Tanks Engineering May 2009