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Page 1

Construction & Commissioning of
BFPL’s 2200 mtpd - World’s Largest

PurifierTM Ammonia Plant


In early 2006, Burrup Fertilisers Pty Ltd (BFPL) completed construction and started up of its 2200
MTPD Ammonia Plant – the world’s largest, single train Purifier based ammonia plant. The plant is
located on the Burrup Peninsula, near Karratha, in the north west of Western Australia.
Commissioning was successfully completed in April 2006 with the inaugural shipment of liquid
ammonia departing from the Port of Dampier in June 2006. This paper presents an overview of the
project and its journey through the various stages of project development, approval, design,
engineering and construction as well as setting out some design specifications and features of the
ammonia plant.

The paper also highlights the environmental and native title management initiatives that were
implemented during the design and construction of this plant to minimize the environmental and
native title impacts on the Burrup Peninsula.


Wolfgang Jovanovic

Burrup Fertilisers Pty Ltd, WA, Australia


Avinash Malhotra
Kellogg Brown & Root LLC, USA





PROJECT OVERVIEW

urrup Fertilisers Pty Ltd (BFPL) has
constructed and commissioned a 2200
metric tons per day ammonia plant in

April 2006. It is the world’s largest single-train
KBR Purifier™ based ammonia plant. BFPL is
a private company incorporated in Australia in
July 2000 and promoted by Oswal Projects
Limited, New Delhi, India. Financial closure for
the project was achieved on 18th December 2002
with the inaugural shipment of liquid ammonia
departing from the Port of Dampier in Western
Australia in June 2006. This was a remarkable

achievement given the scale of this private
development coupled with the numerous
regulatory approvals required.

Having incorporated a company in Australia and
assembled a number of reputable consultants to
provide services to BFPL, Company
representatives first met with officials of the
Department of Industry and Resources in
October 2000 to express the company’s interest
in using a portion of Western Australia’s vast
natural gas supply to manufacture liquid
ammonia, and then ship it to various world

B

2006 267 AMMONIA TECHNICAL MANUAL

Page 2

markets for use as feed stock in the growing
fertiliser businesses on the subcontinent.

BFPL received strong Governmental support
and were granted Major Project Facilitation
Status by the Federal Government of Australia.

The speed at which the project advanced from
this first meeting was extraordinary, given the
extremely detailed and complex negotiations
associated with native title and heritage issues,
environmental and other statuary regulations,
plus the equally demanding due diligence and
bank-ability processes.

As a matter of history, when BFPL initiated
discussions with government officials regarding
construction of its world scale ammonia plant,
five other major projects were in similar
discussions; however only BFPL completed its
project with no others yet to commence.

LOCATION

The new plant is located on the Burrup
Peninsula in the Pilbara region of Western
Australia. The site is in the King Bay – Hearson
Cove industrial area, which is leased from the
Western Australian Government. It is
approximately 1,550 kilometers north-east of
the state capital, Perth.

The Burrup Peninsula is characterized by large
areas of steep, bare rock piles, a high rocky
plateau, stony planes, mudflats, beaches and
bays. The area is vegetated with woodland,
shrubs and grasslands and is populated by birds
and a range of wildlife.

As a result of the areas proximity to offshore oil
and gas supplies and port facilities the Burrup
Peninsula has developed as one of Australia’s
most significant industrial sites and port areas.
Existing industries on the Burrup Peninsula
include the North West Shelf Joint Venture
LNG/LPG Facility, Rio Tinto’s iron ore and salt
production and export facilities.

The plant is serviced locally from the township
of Karratha, 25 kilometers to the south-east.
Karratha has a population of approximately
12,500 people and is geared towards servicing
the resources industry.

BFPL’s ammonia plant is the very first down
stream gas processing facility to operate in the
region and indeed has introduced Australia to
the production of ammonia on a world scale.

FEED STOCK, PORT FACILITIES AND
SHIPPING

Natural gas is supplied to BFPL by the
participants in the Harriet Joint Venture,
comprising subsidiaries of operator Apache
Energy Limited (Apache), the Kuwait Foreign
Petroleum Exploration Company (KUFPEC)
and Tap Oil Limited (Tap). Apache’s parent
company, Apache Corporation, is one of the
world’s leading independent oil and gas
companies. Gas is supplied by the Harriet Joint
Venture from the Varanus Island production
hub. The design composition is shown in Table
1.


Volume Percent
Methane 80.49
Ethane 6.38
Propane + 4.63
Carbon Dioxide 5.00
Nitrogen 3.50

100.0

Table 1: Design composition of natural gas feed.

Water – seawater for cooling purposes and
desalinated for use in ammonia production –
will be supplied by the Western Australian
Governments’ Water Corporation. The Water
Corporation has constructed a new desalination
plant adjacent to BFPL’s ammonia plant.

Ammonia will be stored at the plant site in two
40,000 tons storage tanks until ready for loading
at the Port of Dampiers’ new Bulk Liquids
Berth (BLB) facility. It will be transported to

Page 3

the Port via a 5.5 kilometer product pipeline and
loaded directly onto ships using dedicated ship
loading facilities established by BFPL on the
new BLB.

Vessels capable of storing up to 40,000 tons of
refrigerated liquid ammonia will be used to
transport the ammonia to the world markets.

Yara, one of the world’s largest traders and
shipper of ammonia, will purchase 100% of
ammonia produced at the plant. BFPL and Yara
have agreed on the terms of an Off-take and
Marketing Support Agreement. Subsequent to
establishing that agreement Yara has taken out a
portion of ownership in BFPL thus
strengthening the relationship between the two
parties.

PROJECT EXECUTION

Development of the project was managed by
BFPL who was supported by a number of
external technical, consulting and management
service providers. A key feature of the execution
strategy was to ensure that a safe, efficient and
reliable plant was designed and constructed on
the strength of proven technology enlisting the
support of experienced contractors, suppliers
and vendors.

As the major investor, Oswal/BFPL assumed
full responsibility for the project.
Comprehensive and effective management was
achieved by adopting international good
practices in contracting and construction
management. Contracts for license, and basic
engineering design packages relating to the
ammonia plant were awarded to Kellogg Brown
& Root, Inc. (KBR), now Kellogg Brown &
Root, LLC. Training and start-up advisory

services were provided by KBR. Emphasis was
placed on working as a combined project team.

An Engineering, Procurement and Construction
Management (EPC) contract was awarded to
SNC-Lavalin (SNC) under a lump-sum-turn-
key, fixed price arrangement. This arrangement
involved ensuring overall compliance with the
Construction Environmental Management Plan
and other legislative requirements, and assisting
in obtaining permits necessary for construction.

Worley Parsons provided independent
engineering services, audits and consultancy
services.

Construction of the new ammonia plant by
BFPL acted as a catalyst for a host of other
projects to go forward in the region. The State
Government of Western Australia committed
AUS$137million for the development of multi-
user infrastructure to support new projects on
the Burrup Peninsula. The Department of
Industry and Resources (DoIR) played a role in
facilitating the identification and development
of the infrastructure. The infrastructure included
a Water Corporation seawater supply and brine
return facility, a natural gas supply pipeline to
the new ammonia plant, multi-user service
corridors by Landcorp connecting the King Bay-
Hearson Cove development area to the Dampier
Port area, upgrades to the Dampier Port
Authority facilities including a new bulk liquids
berth and utilities such as roads and
telecommunications. Another significant project
was the construction of a new desalination plant
adjacent to the ammonia plant.

KBR on-site representatives and vendor
representatives monitored the start up and
commissioning.


2006 269 AMMONIA TECHNICAL MANUAL

Page 4

Project Milestones

A summary of the project milestones is shown
in Table 2.
First Meeting with
Government Officials

October 2000

Works Approvals Granted Q2 2002
Environmental & Heritage
Clearances Received

Q3 2002

Engineering Commenced Q4 2002
Financial Close 18 Dec. 2002
Planning Approval
Received. Aboriginal
Heritage Management Plan
Approved

Q1 2003

Construction commenced
on-site

Q2 2003

Major earthworks and site
preparation completed.
Concrete works commenced

Q3 2003

Desalination plant area
handed over to Water
Corporation. Major design
review conducted

Q4 2003

Ammonia Tanks Erection
Commenced & Structural
Steel Erection Package
Awarded

Q1 2004

Structural Mechanical
Contractor mobilised

Q2 2004

Electrical Installation
Commenced

Q3 2004

Roof raised into position on
first ammonia storage tank &
41 large vessels erected over
a six week period (heaviest
was the ammonia synthesis
converter at 780 tons)

Q4 2004

Emergency Diesel Generator
commissioned

Q1 2005

Two boilers (150 tph and 50
tph) commissioned

Q2 2005

Other OSBL Components
commissioned

Q3 2005

Pre-commissioning of ISBL
components commenced

Q4 2005

Mechanical Completion Q1 2006
First Ammonia Production Q2 2006
Performance Test Q2 2006
Inaugural Shipment Q2 2006

Native Title, Environmental & Health and
Safety Issues

The Burrup Peninsula and surrounding Dampier
Archipelago in the Western Australia’s Pilbara
region have significant biodiversity values with
many flora species. Many of the Peninsula’s
fauna are found throughout the Pilbara region
and numerous archaeological surveys confirmed
that Aboriginals have inhabited the Burrup
Peninsula for over 7,000 years. In view of all
this BFPL initiated the development of the
following three plans:

• Aboriginal Heritage Management Plan:

During the feasibility study phase of the
project BFPL engaged consultants to
undertake archaeological surveys and
developed an Aboriginal Heritage
Management Plan. BFPL, in consultation
with the Native Title Groups, engaged a
number of Aboriginal employees on site
during earthworks to ensure that the project
protected and preserved existing Aboriginal
sites. Where disturbance could not be
avoided the disturbance was undertaken in
accordance with conditions pursuant to the
Aboriginal Heritage Act.


• Construction Environmental Management

Plan (CEMP): This CEMP was prepared to
outline strategies that would be initiated in
order to reduce any adverse environmental
impacts that might occur and to ensure that
environmental standards are achieved during
construction. The CEMP addressed a
number of specific environmental factors
such as dust, noise and traffic management
during construction.


• Health and Safety Management Plan: This

plan was prepared to provide guidance in
Health and Safety related matters to all
parties associated with the project. This plan
provided advice on safe work practices and
safety procedures, safety inspections and
audits, incident and accident management

Page 5

measures and information concerning
occupational health.


The potential impact of the new plant in relation
to emissions, flora and fauna, water pollution
and waste was assessed and documented in a
Public Environmental Review (PER). The PER
was prepared by BFPL’s Corporate
Environmental Advisors, Sinclair Knight Merz
(SKM) and concluded that:

• The impact of the plant development and

operations in relation to flora and fauna,
marine environment, noise, waste, public
safety and aesthetics will be minimal.

• The plant will produce atmospheric
emissions but these are well within “national
environmental protection measures” at “best
available techniques”.

• BFPL was committed to formulating and
implementing a comprehensive
environmental management plan.

• During the PER public consultation period,
BFPL did not receive any public
submissions objecting to the project.

THE AMMONIA PLANT PROCESS

The ammonia process (refer figure 1) is based
on the Purifier™ Process, a low energy natural
gas reforming process offered and licensed by
KBR. The ammonia plant design is based upon
producing cold 2200 MTPD ammonia, which is
exported to atmospheric ammonia storage at -33
°C.

All the components of the ammonia plant are
based on well proven technology features. All
process equipment is single train. All
compressors are centrifugal compressors and
each is driven by a steam turbine.

The desulfurized feed is mixed with medium
pressure steam, and the mixture is preheated in
the convection section of a top fired primary

reformer. The preheated mixed feed is then
distributed to tubes suspended in the radiant
section. The tubes contain nickel reforming
catalyst. The heat for the endothermic reforming
reaction is provided by combustion of fuel gas
and waste gas from Purifier. The burners are
located between the rows of catalyst tubes and
operate with downward firing. In this manner,
the tubes are heated from both sides. Also, the
heat flux is the highest at the top of the tubes,
where the process temperature is the lowest.
That results in a relatively even load on the
tubes.

The outlet manifolds and the riser tubes are
located inside the reformer furnace, for heat
conservation.

The primary reformer uses the latest refractory
and insulation technology. Ceramic fiber lining
in the radiant section provides rapid thermal
response due to low heat storage. Super duty
hard refractory is used where flames may
contact the sidewalls. This reformer design
allows operation of the primary reformer with
only two percent oxygen (on dry basis) at the
exit of the radiant section.

The primary reformer is designed to obtain
maximum thermal efficiency (93 % plus) by
recovering heat from the flue gas in a
convection section. The recovered heat is used
for the following services:

• Mixed-feed (gas-steam) preheating

• Process air preheating

• Steam superheating

• Feed gas preheating

• Combustion air preheating


In the secondary reformer, the partially
reformed gas from the primary reformer is
reacted with air. In a traditional ammonia plant,
the air flow rate is set to provide the amount of

2006 271 AMMONIA TECHNICAL MANUAL

Page 6

nitrogen required for the ammonia synthesis
reaction. In a Purifier™ ammonia plant, up to
50 percent excess air is used. The oxygen in the
air burns some of the process gas, to provide
heat for the reforming reaction. The gas then
flows downward through a bed of nickel
reforming catalyst, where the temperature
decreases due to the endothermic reforming
reaction.

The excess air in the Purifier™ process provides
heat for more reaction in the secondary
reformer. This reduces the size of the primary
reformer by about one third, and lowers the
process outlet temperature (~725 °C)
substantially, as compared to a traditional
ammonia plant. The lower operating
temperature results in a longer tube and catalyst
life. The shift of reforming duty from the
primary to the secondary reformer is
advantageous, because the heat in the secondary
reformer is recovered 100 percent in the
process, with no stack loss.

The secondary reformer has a dual-layer
refractory lining. An outside water jacket
protects the shell against hot spots in the event
of a refractory failure The effluent from the
secondary reforming containing about 2.0% (dry
basis) methane is cooled by generating and
superheating high pressure steam prior to shift
conversion.

Shift conversion uses the traditional two-stage
high and low temperature reactors. Carbon
dioxide is removed by a two stage proven
processes licensed from by BASF. Process
condensate is recovered, stripped with medium
pressure steam in the Condensate Stripper, and
recycled as process steam to the reforming
section. The synthesis gas from the CO2
absorber overhead is heated in a feed/effluent
exchanger and then passed over methanation
catalyst to convert residual carbon oxides to
methane.


In preparation for drying, the methanator
effluent is cooled by heat exchange with
methanator feed and cooling water. The
methanator effluent, then combines with recycle
synthesis loop purge gas and are further cooled
with ammonia refrigerant to about 4°C. The
chilled gas from the condensate separator drum
goes to the syngas dryers. Two dryers are
provided. They contain mol sieve desiccant and
operate on a 24-hour cycle. Exiting these driers
the total of water, CO2 and NH3 content is
reduced to less than 1.0 ppmv. The regeneration
of the molecular sieve dryers is done with the
waste gas from the Purifier.

The cryogenic Purifier does the final
purification of the raw synthesis gas. It consists
of three pieces of equipment, a feed/effluent
exchanger, a low speed expander and a
rectifying column with an integral overhead
condenser. The dried feed to the Purifier with
H/N ratio of about 2.0 is first cooled in the top
part of the feed/effluent exchanger by exchange
with the purified gas and waste gas. It then
flows through a turbo-expander where feed is
expanded and energy is recovered to develop
the net refrigeration required for the cryogenic
unit. The expander effluent is further cooled and
partially condensed in the bottom of the
exchanger and then enters the rectifier column.
All of the methane, about 60% of the argon and
all the excess nitrogen coming to the Purifier are
removed as rectifier “bottoms”. Liquid from the
bottom of the rectifier is partially evaporated at
reduced pressure in the shell side of the rectifier
overhead condenser to provide reflux for the
column.

It is further reheated by exchange with Purifier
feed gas and then leaves as a waste gas to
regenerate the molecular sieve dryers. The
waste gas is then used as fuel in the process
heater. The synthesis gas containing about 0.25
percent argon and an H/N ratio of three is
reheated by exchange with Purifier feed and
then goes to the suction of the synthesis gas
compressor.

Page 7

The purified gas is compressed to about 150
bars while combining with unreacted recycle
gas. Compressor discharge is heated by
feed/effluent exchange, and enters the horizontal
converter. In the converter ammonia conversion
is raised from about two percent to nineteen
percent while passing over three beds of
magnetite catalyst. Converter effluent is cooled
by generating high pressure steam, by
feed/effluent exchange, with cooling water, and
finally in KBR’s proprietary “Unitized Chiller”.
A conventional refrigeration system provides
the necessary chilling. A small purge stream is
recycled to upstream of the dryers in order to
recover the hydrogen and nitrogen. Cold
ammonia product is exported from the synthesis
loop to storage.

PROCESS DESIGN FEATURES

There were several unique features in the BFPL
design, as discussed below.

• Integral gear process air compressor driven

by a steam turbine – first large capacity
Purifier™ ammonia plant, which has not
used gas turbine

• Mild operating conditions for primary
reforming

• About 42 percent excess air to the secondary
reformer

• Non metallic mixing chamber – no metallic
mixer/burner in the secondary reformer

• BASF’s aMDEA two stage process for
carbon dioxide removal

• KBR’s cryogenic Purifier to remove inerts
from the raw synthesis gas

• Three beds with two exchangers horizontal
magnetite converter

• Unitized ammonia chiller

The ammonia plant for BFPL is the second
KBR plant to combine features of both Kellogg
and Braun technologies. The first plant was the
CNOOC(1) ammonia plant, which was
commissioned in September 2003. Compared to
previous Purifier plant designs, the BFPL &

CNOOC ammonia plants use KBR’s proprietary
high efficiency reformer furnace design with
reforming at a pressure of 40 bars, about 10 bars
higher than previously used. This raises the
pressure in the Purifier column, which makes
the separation easier. Thus the higher than
normal methane slip from the reforming section
was easily accommodated. The horizontal
ammonia converter and unitized chiller reduce
the synthesis loop pressure drop by about 3 bars
when compared to previous Purifier loops.
These factors help reduce energy consumption
of the ammonia plant.

PLANT PERFORMANCE

The ammonia plant was started up in March
2006. Gas feed was on March 12 and first
ammonia produced on April 11. The
performance test for the ammonia plant was
conducted in June of 2006 and all performance
guarantees were met. Ammonia plant has been
operating at more than 100% of the design
capacity.

The ammonia plant energy consumption and
quality achieved during the performance test is
shown in Table 3. The values represent energy
in terms of Gcal per metric ton of cold ammonia
product on a lower heating value basis.

Measured Expected
Natural Gas Gcal/mt
Feed 5.76 6.05
Fuel 1.59 1.43
Export steam -0.61 -0.66
Electricity import 0.04 0.04
Total Gcal/mt 6.78 6.86
Ammonia Quality
Water, wt% 0.04 0.1
Oil. ppmw Not Detected 5 max


Table 3: A comparison of ammonia plant energy
consumption as measured during performance test
and as expected from the process flow diagrams

The “measured” values were calculated from the
performance test. The “expected” values are

2006 273 AMMONIA TECHNICAL MANUAL

Page 8

from the design issue of the process flow
diagrams.

SUMMARY

The new ammonia plant is a major
accomplishment for BFPL. A private
company has successfully introduced world
scale ammonia technology to Australia and
done so in an extraordinarily short space of
time –given the extremely detailed and
complex negotiation associated with a plant
of its size and nature. BFPL has succeeded
where many other, larger publicly listed
organizations have not. The plants’
successful completion represents the first
downstream gas processing facility in
Western Australia. Indeed the Major
Project Facilitation Status afforded to the
project by the Federal Government of
Australia coupled with the level of Western
Australian Government investment in
infrastructure demonstrates the strong
support that BFPL received from both
Governments.

The ammonia plant also represents a significant
accomplishment for KBR in the provision of its
leading edge technology. It is the second KBR
Purifier™ based ammonia plant to come-on
stream which includes features from both
Kellogg and Braun Technologies – the result
being a new KBR Purifier™ Process that is now
a proven technology for one of the largest
capacity single stream ammonia plant. The
combination of features from the two former
companies has further reduced the energy
consumption of the Purifier™ Process.

(1) Yang Yexin & Gosnell, J. H. “CNOOC
Chemicals Ltd. New Fertilizer Plant”, AIChE
Safety in Ammonia Plants & Related Facilities
Symposium 2004, Denver, Colorado, USA,
September 2004.

2006AMMONIA TECHNICAL MANUAL 274

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