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DEPARTMENT OF PETROLEUM AND GAS ENGINEERING UNIVERSITY OF PORT HARCOURT
A
SEMINAR
ON
MARKET POTENTIALS OF GAS TO LIQUID TECHNOLOGY AND ITS COMPARISON WITH
LIQUIFIED NATURAL GAS.
BY
MAMHOBU-AMADI, CHIJEMEZU (MATRIC NO. U2004/3070268)
SUBMITTED
TO
DR. I. A. B. EKEJIUBA
DEPARTMENT OF PETROLUEM AND GAS ENGINEERING UNIVERSITY OF PORT HARCOURT.
OCTOBER, 2009.
ABSTRACT:
A large portion of world’s natural gas reserves are “stranded” resources, the drive
to monetize these resources leads to the development of gas-to-liquids (GTL) and
liquefied natural gas (LNG) technologies. LNG has the advantage of having been
developed for the past 40 years and having an excellent safety record. GTL on the
other hand is another option with substantial benefits, but its development stage
and commercial viability are far behind LNG. This paper presents a techno-
economic comparison of GTL with LNG, including technical development, market
potential for the products, and capital cost for the infrastructure. The aim is to give
an overall view on both LNG and GTL and provide a perspective on the
profitability of these two technologies.
CHAPTER ONE
1.0 INTRODUCTION
Gas to liquid (GTL) provide ultra clean fuel that can dramatically improve
air quality in the major metropolitan areas of the world. Gas to liquid
technology uses syngas production and the Fischer – Tropsch synthesis
process to convert natural gas into liquid synthetic fuels. Unlike products
refined from crude oil, GTL fuels are crystal clean and free from sulphur and
aromatic pollutants – greatly exceeding new and proposed Japanese,
European Union and U.S. environmental regulations. GTL fuels can be used
to run diesel engines, jet and natural gas turbines and also fuel cells. We
believe that we can create value for our shareholders by applying this
technology to the abundant natural gas available throughout the world and
primarily in the Middle East. Engineering advances and exciting new
catalyst formulations have dramatically reduced the capital cost of
producing super clean fuels from natural gas.
The GTL Technology has the potential to convert the trillions of cubic feet
of stranded natural gas worldwide into billions of barrels of economic value.
Countries that control the gas, will realize great value from the investments,
jobs and revenue that will result from the development of these resources.
Furthermore, the products and fuel from GTL plants can be transported and
sold through conventional infrastructure, such as tankers, pipelines, storage
facilities and existing retail distribution systems. The process yields the
highest quality synthetic hydrocarbons than can be used directly as a fuel in
a normal diesel engine, or blended with lower quality crude oil – derived
diesel fuel to help meet more stringent engine exhaust standards and
increased performance requirements.
While the GTL process can be designed to refine several types of products,
our focus will be on diesel as a transportation fuel and naphtha as a chemical
feed stock. Ultra – clean diesel has two natural markets: it can be blended
with conventional diesel to meet lower sulphur specifications and be used as
a cost effective alternative to more costly refining processes. It can also be
sold as a specialty product to major cities for use in buses, trucks, taxis etc.
to alleviate air pollution problems. Many of the world’s cities are in need of
such an alternative fuel application that functions better than conventional
fuels, including compressed natural gas. The ultra-clean naphtha product is
ideally suited to ethylene cracking for the manufacture of petrochemicals
because of its high paraffin content. Both the diesel and naphtha market are
significant today in absolute terms and expanding at strong rates of growth.
The clean diesel product is likely to have the highest demand in the Far East
and Europe while the high value naphtha will probably be consumed in the
Middle East.
GTL not only adds value, but also is capable of producing product that could
be sold or blended into refinery stock as superior product with fewer
pollutants, for which there is growing demand. Reflecting its origin as a gas,
gas-to-liquid processes produce diesel fuel with an energy density
comparable to conversional diesel, but with a higher cetane number,
permitting a superior performance engine design.
Another problem emission associated with diesel fuel is particulate matter,
which is composed of un-burnt carbon and aromatics and compounds of
sulfur. Fine particulates are associated with respiratory problems, while
certain complex aromatics have been found to be carcinogenic. Low sulphur
content, leads to significant reductions in particulate matter that is generated
during combustion, and the low aromatics content reduces the toxicity of the
particulate matter reflecting in a worldwide trend towards the reduction of
sulphur and aromatics in fuel.
The cetane number indicates how quickly the fuel will auto-ignite, and how
evenly it will combust. Most countries require a minimum cetane number of
around 45 to 50: A higher cetane number represents a lower flame
temperature, providing a reduction in the formation of oxides of nitrogen
(NOx) that contributes to uban smog and ground level ozone.
1.1 WHY GAS TO LIQUID (GTL)
(i) Expanding utilization of Natural gas: Great expectations for expanding
utilization of natural gas are being held by the world’s energy market
from the standpoint of addressing the global environmental problems.
Converting natural gas into energy in liquid state is thought to be One of
the best ways of expanding natural gas utilization and having natural gas
complete with petroleum.
(ii) Strengthened restriction measures on gas flaring: GTL is been
watched with keen interest also from the standpoint of natural gas
resources. Nigeria’s push to the end of gas flaring before the end of the
decade means oil field developers are forced to find an outlet for natural
gas. GTL technology could be a way out.
(iii) Strengthening of quality regulations of transportation fuel: Due to
environmental pollution prevention each country in the world is making
plans to further strengthen measure to counter the issue of automotive
emissions. Since sulphur contained in the diesel fuel tends to increase the
quantity of particulate matter in the automotive emissions, plans are
underway to strengthen the quality regulation of diesel fuel in most of the
countries, of the world.
(iv) Escalation in oil price and refining margin: Escalation in crude oil
prices will make GTL products more valuable, while the shift towards
gas in many companies reserve portfolio promises plenty of cheap, feed
gas looking for a path to market.
(v) Market diversification: GTL can increase the market diversification of a
producer’s portfolio. This is the main reasons that Sasol / Chevron and
Nigerian government is pursuing GTL technology.
(vi) Increase in the world’s proved natural gas resources
(vii) GTL technology advancement.
1.2 BENEFITS OF GAS TO LIQUID TECHNOLOGY
1.2.1 MONITIZING GAS RESERVES:
GTL has the potential to convert a significant percentage of the world’s
estimated proved and potential gas reserves – estimated to be upwards of
14,000 TCF of natural gas, which today holds little or no economic value,
into several hundred billion barrels of all equivalent of great economic value
to the companies and countries that control them.
1.2.2 ELIMINATING COSTLY OR ENVIRONMENTALLY DISADVANTAGEOUS
PRACTICES :
GTL will help eliminate the need for flaring or re-injecting natural gas,
permitting early development and production of oil fields shut in by the
inability to dispose of associated gas and reducing the negative
environmental impact of flaring.
1.2.3 ECONOMIC DEVELOPMENT OF REMOTE GAS:
GTL will permit the economic development of remote gas discoveries that
are otherwise deemed too far from market to have any economical value.
1.2.4 ENVIRONMENTALLY – SUPERIOR LIQUID FUELS:
GTL will yield synthetic hydrocarbons of the highest quality that can be
used directly as fuels or blended with lower quality crude oil derived fuels to
bring them up to compliance with more stringent environmental and
performance specifications.
From the foregoing, it is worthy of note that one major attraction of GTL
conversion is that it enables stranded gas reserves to be transported to
market through existing oil pipelines, avoiding complexities attending the
permitting, regulation and operation of new gas pipeline systems. However,
it will be interesting to know that GTL is not viable everywhere.
The major factors affecting its viability are:
Premium gas resource
Oil and gas price and capital cost
Financial strength and freedom to operate
Large project execution skill
Global marketing capability
1.3 STATEMENT OF THE PROBLEM
In Nigeria today, everybody is depending solely on crude oil. It has also
been discovered that a time in the future, that Nigeria will run short of oil.
For this singular reason, a large number of industrial and government
sponsored programmes to develop commercially viable process options are
in various stages of development.
The Nigerian government recently announced a gas reserve base of 170 tcf
to 200 tcf, 120 tcf of which is proven and uncommitted. In addition, as much
as 90% of discovered oil reservoirs are estimated to constitute the oil leg to a
gas cap. While this situation seems to tend itself well to an LNG exploitation
strategy, the logistics of gathering discovered gas to a central point are
almost impossible as these reserves are scattered in small 1 – 3 tcf deposits
among hundreds of fields across the highly fragmented Niger Delta.
Therefore, with the exception of a few large concentrations, such as the case
of Shell’s Bonny LNG plant, much of the country’s gas remain stranded, re-
injected or part of the estimated 2bcf that is flared daily making Nigeria the
highest gas flaring in the world. Thus effective utilization of natural gas
resources being flared daily is an urgent task to be addressed also from the
environmental protection standpoint.
1.4 OBJECTIVE OF THE STUDY
With the oil price reaching the climax recently, coupled with dampening oil
reserve and global warming, interest has been on production of liquid
hydrocarbon through Fischer – Tropsch (FT) synthesis. Even though FT
synthesis has long been a technically proven technology, the development of
commercial GTL technology has been gradual and slow. The major factor
affecting the development of GTL is economics. This has made its economic
viability a major concern among major resource holders.
Therefore, it is the aim of this project to:
(i) Study the overall process scheme of Fischer Tropsch Gas-to-Liquid
Technology
(ii) Study the techno-economic comparison of GTL and LNG
(iii) Highlight the early efforts to upgrade Fischer Tropsch reaction into
fuel, lubricants and useful products.
CHAPTER TWO
2.0 LITERATURE REVIEW
2.1 HISTORICAL BACKGROUND OF GTL
Petroleum came from two Greek words, Petras meaning rock and Oleum
meaning oil. Therefore petroleum is defined as oil from rock. Also it is
clearly the fuel of the future, and to insure that Germany would not lack a
plentiful supply, German scientist and engineers synthesized petroleum from
their country’s abundant coal supplies and thereby established the world’s
first technology successfully synthetic fuel industry. Of the several
conversion processes the Germans developed, high – pressure coal
hydrographic or liquefaction and the Fisher – Tropsch Synthesis (F-T) were
the most advanced Friedrich Bergius (1884 – 1949) launched the German
program for energy independence with the invention of high-pressure coal
hydrogenation in the years 1910 – 25. Franz Fischer (1877 – 1947) and Hans
Tropsch broadened it with the gaseous synthesis of liquid fuels in the mid –
1920s Farben, Ruhrehemie, and others industrialized the German energy
program with their development of the Bergius process and Fischer –
Tropsch Synthesis from the 1920s to the end of World War II. Germans
successfully used gas derived from coal to feed Fischer – Tropsch plants to
provide diesel and gasoline for its armies during World War II. The process
largely fell into disuse after the war due to the availability of relatively
cheap oil. However, the isolation of South Africa under apartheid regime
created strategic issues for the then government. These issues coupled with
the relative abundance of coal in South Africa led to the establishment of
sasol in 1955 and subsequently the development and refinement of a Fischer
– Tropsch based industry converting coal to liquid fuel / chemicals.
South Africa was home to world’s largest GTL plant, the 30,000 bpd Mossel
Bay facility, until it was eclipsed by the June 2006 start up of Sasol /
chevron and Qatar Petroleum’s 34,000 bpd Oryx plant in Qatar. The only
commercial scale GTL project currently in operation is Shell’s 14,700 bpd
Bintulu plant in Malaysia, there are also more than ten pilot GTL plants
(with outputs between two to 400 bpd) around the world.
FIGURE 2.1
SCAN SHELL GTL PLANT IN BINTULU, MALAYSIA (CLEK OFOMA PG 5)
2.2 COMMERCIAL EXAMPLES
2.2.1 SASOL
Sasol is a synfuel technology supplier established to provide petroleum
products in coal-rich but oil-poor South Africa. The firm has built a series of
Fischer Tropsch coal-to-oil plants, and is one of the world’s most
experienced synthetic fuel organization and now marketing a natural gas to
oil technology. It has developed the world’s largest synthetic fuel project,
the Mossgas complex at Mossel Bay in South Africa that was commissioned
in 1993 and produces a small volume of 25,000 bpd. To increase the
proportion of higher molecular weight hydrocarbon, Sasol has modified its
Arge reactor to operate at higher pressures.
(SCAN PG 4 OF OFOMA)
FIGURE 2.2 SASOL SYNTHETIC FUEL PLANT
Sasol has commercialized four reactor types with the slurry phase distillate
process being the most recent. Its products are more olefinic than those from
the fixed bed reactors and are hydrogenated to straight chain paraffins. Its
slurry phase Distillate converts natural gas into liquid fuels, most notably
superior quality diesel using technology developed from the conventional
Arge tabular fixed bed reactor technology. The resultant diesel is suitable as
a premium blending component for standard and diesel grades from
conventional crude oil refineries. Blended with lower grade diesel it assists
to comply with the increasingly stringent specifications being set for
transport fuels in North America and Europe.
The other technology uses the Sasol Advanced Synthol (SAS) reactor to
produce mainly light olefins and gasoline fractions. Sasol has developed
high performance cobalt – based and iron based catalysts for these
processes. The company claims a single molecule or Sasol Slurry Phase
Distillate Plant that converts 100MMScfd of natural gas into 10,000 bpd of
liquid transport fuels that can be built at a capital cost of about US$ 250
million. This cost equates to a cost per daily barrel of capacity of about
US$250,000 including utilities, off-site facilities and infrastructure units. If
priced at US$0.5/MMBtu, the gas amount to a feed stock cost of US$5 per
barrel of product. The fixed and variable operating cost (including labour,
maintenance and catalyst) are estimated at a further US$5 per barrel of
product, thereby resulting in a direct cash cost of production of about US$10
a barrel (excluding depreciation). These costs should however be compared
with independent assessments.
In June 1999, Chevron and Sasol agreed to an alliance to create ventures
using Sasol’s GTL Technology. The two companies have conducted a
feasibility study to build a GTL plant in Nigeria that would begin operation
in 2010. Sasol reportedly also has been in discussions with Norway’s Statoil,
but no definite announcements have been made.
2.2.2 STATOIL
With its large gas reserves, Norway’s statoil has been developing catalyst
and process rectors for an F-T process to produce middle distillates from
natural gas. The statoil process employs a three phase slurry type reactor in
which syngas is feed to a suspension of catalyst particles in a hydrocarbon
slurry which is a product of three processes itself. The processes continuous
to be challenged by catalyst performance and the ability to continuously
extract the liquid product.
2.2.3 SHELL
Shell has carried out R&D since the late 1940s on the conversion of natural
gas, leading to the development of the shell middle Distillate synthesis
(SMDS) route, a modified F-T process. But unlike other F-T synthesis
routes focuses on maximizing yields of middle distillates notably kerosene
and gas oil.
Shell has built a 12,000 b/d plant in 1993 in Bintulu, Malaysia (see fig 2.1).
The process consists of three steps. The production of syngas with a H2: CO
ratio of 2.1; syngas conversion to high molecular weight hydrocarbons via
F-T using a high performance catalyst; and hydro cracking and
hydroisomerisation to maximize the middle distillate yield. The products are
highly paraffinic and free from nitrogen and sulphur.
Shell is inverting US$6 billion in gas to liquid technologies over 10 years
with four plants. It announced in October 2000, agreement with the Egyptian
government for a 75,000 b/d facility and a similar plant for Trinidad &
Tobago.
In April 2001, it announce interest for plants in Australia and Malaysia at
75,000 b/d costing US$1.6 billion.
2.2.4 EXXON
Exxon has developed a commercial F-T system from natural gas feed stock
Exxon claims its slurry design reactor and proprietary catalyst systems
results in high productivity and selectivity along with significant economy of
scale benefits. Exxon employes a three step process: fluid bed synthesis gas
generation by catalytic partial oxidation, slurry phase F-T synthesis; and
fixed bed product upgrade by hydroisomerisation. The process can be
adjusted to produce a range of products. More recently, Exxon has
developed a new chemical method based on the Fischer – Tropsch process,
to synthesis diesel fuel from natural gas. Exxon claims better catalyst and
improved oxygen – extraction technologies have reduced the capital cost of
the process and is actively marketing the process internationally.
2.2.5 SYNTROLEUM
The Syntroleum Corporation of the USA is marketing an alternative natural
gas to diesel technology based on the F-T process. It claimed to be
competitive as it has a lower capital cost due to the redesign of the reactor,
using an air-based autothermal gas preparation to eliminate the significant
capital expense of an air separation plant, and high yields using their
catalyst. It claims to be able to produce synthetic crude at around $20 per
bbl. The syncrude can be further subjected to hydro-cracking and
fractionation to produce a diesel/naphtha/kerosene range at the user’s
discretion. The company indicates it process has a capital cost of around
$13,000 per daily barrel of diesel for a 20,000 to 25,000 bpd facility and an
operating cost of between $3.50 to $5.70 per barrel. The thermal efficiency
of the syntroleum process is reported to be about 60 percent, implying a
requirement for about 90 million, cubic feet (85 terajoules) per day of dry
gas for a $300 to $350 million, 25,000 barrel per day capacity facility. These
figures therefore suggests a unit cost of less than $20 per barrel ($3.20 per
giga joule) of diesel fuel. The company claims the required economic scale
would be similar if based on LNG.
Table 2.1 locations and estimated capacities of existing and potential commercial GTL plants:COUNTRY COMPANY CAPACITY, B/D
Australia Sasol Chevron Texaco 50,000
Australia Shell 75,000
Bolivia GTL Bolivia 10,000
Bolivia Repsol YPE, Syntroleum 103,500
Egypt Shell EGPC 75,000
Indonesia Shell 75,000
Indonesia Pertamina, Rentech 16,000
Iran Shell 75,000
Iran Sasol 110,000
Nigeria Chevron Texaco, Sasol, NNPC 34,000
Malaysia Shell 12,500
Peru Syntroleum 40,000
Qatar Shell, QPC 75,000
Qatar Exxon Mobil, QPC 100,000
Qatar Sasol, QPC 34,000
South Africa PetroSA 30,000
United States ANGTL 50,000
Venezuela PDVSA 15,000
Total 980,000
2.3 ENVIRONMENTAL IMPACTS AND BENEFITS OF G.T.L
Converting natural gas to liquid fuel benefits the environments in two ways.
First, the regulating liquid hydrocarbons are pure and burn cleanly. They are
colourless, odourless and low in toxicity. Second, converting gas to liquid
allows producers to transport and market associated gas that would
otherwise be flared into the atmosphere.
The clean-burning properties of diesel derived from converted natural gas
were recognized as soon as Fischer and Tropsch tested their synthesized
liquid fuel. Their synthetic diesel burned with reglible emissions and was
preferred over petroleum – based diesels for powering underground motors.
Liquid fuels distilled form crude petroleum typically contain sulphur,
nitrogen, aromatic compounds and other impurities. When burned, these
crude – based fuel emit carbon monoxide, sulphur and nitrogen oxides and
particulates, all of which contributes to air pollution and the green house
effect. It also has a certain number between 75 and 80 compared to a typical
refinery diesel of less than 50, which further improves its combustion
properties.
Two disadvantages of G.T.L diesel are its relatively low density and poor
lubricating qualities, which can however be overcome by the addition of
additives or by blending with regular refinery fuel. Concerns over the
environmental effects of fossil fuel combustion have led global
organizations to encourage efforts to reduce industry and transportation
related emissions. Several countries now have legislated goals to improve
the quality of fuel used for transportation.
Further environmental benefits of G.T.L conversion come from facilitating
production and transportation of associated gas that is normally flared.
When allowed, operators flare produced gas if their field’s surface facilities
are designed solely for oil production of if the gas cannot be re-injected.
However, flaring waste natural resources and contributes to air pollution.
Reducing the amount of gas flared requires curbing gas production, which is
linked to oil production. For many fields with associated gas, stick limits on
gas production translate into limits on oil production that can eventually
make oil production uneconomic.
Up until a few years ago, mentioning the word diesel used to bring to mind
words such as “smell”, “smoke”, and “rattle”. Just how much things have
changed has been illustrated by this year’s new racing car entry in the 24
Heures du Mans race (Le Mans). Back in December 2005, the Audi R10, a
diesel-powered car, was unveiled as capable of winning the famous Le Mans
24 hour race. With huge torque and superior fuel economy the car’s bid for
Le Mans is as credible as any gasoline entry and, furthermore, at the Paris
launch of the car, there was no smell, no smoke and no rattle. Indeed, the
car’s driver and seven-time Le Mans winner Tom Kristensen commented
that the almost total absence of noise is one of the things he and other R10
drivers will need to get used to. So what has changed?
Certainly one of the elements is the fuel. Indeed, the Audi R10 will be
powered by Shell V-Power Diesel. Whilst the project will see two of the
biggest names in motor sport striving for an historic milestone in racing, the
expertise behind the technology comes from a deep understanding of what
works on the road. Audi, inventor of the TDi technology and pioneer of the
European diesel revolution, has worked extensively with Shell in the past –
and has been involved in the development and testing of Shell V-Power
Diesel. This advanced fuel is designed to help the latest generation of diesel
engines to continuously deliver more power, and will utilise Shell’s
exclusive synthetic GTL Fuel technology. Shell has led the introduction of
this innovative fuel technology and is already supplying GTL Fuel
through more than 3,000 of its service stations across Europe as the special
ingredient at the heart of Shell V-Power Diesel. GTL Fuel has the
advantage that although new to motorists, it has been produced for over a
decade using tried and tested technology. It is the gasoil or diesel fraction
produced from the Fischer-Tropsch process, so called after its inventors,
which consists of a catalytic chemical conversion of natural gas into
synthetic liquid oil products. Shell first embarked on research into Gas to
Liquids technology in the early 1970s, leading to the commissioning of the
Bintulu plant in 1993 that has successfully delivered more than a thousand
shipments of GTL products. The operational experience gained at Bintulu
over the past decade has helped to drive improvements in the performance
and reliability of the plant, creating a safe, efficient and profitable business.
Shell is now applying this accumulated knowledge and experience to the
development of world-scale GTL projects, such as the Pearl GTL project in
Qatar. In addition to GTL Fuel, GTL plants produce a range of other
products, including chemical feedstocks, naphtha and lubricant base oils, all
of which are already successfully marketed from Bintulu.
Compared to the traditional route of extracting normal paraffin from
kerosene, the GTL route is simpler and has significant capital and operating
cost advantages. In the future, GTL technology could largely replace
traditional technology to meet the growth in demand for normal paraffin.
GTL Base Oils have unique properties with low volatility and a high
viscosity index that will provide a further catalyst for cleaner and higher
performance engine designs. GTL Fuel is fully fungible with refinery-
derived gasoil, and could easily be absorbed by the highly liquid,
commodity gasoil market. Any premium for the product is based upon
tangible benefits derived from the unique properties of the molecule -
virtually zero aromatics and sulphur, and high cetane - and the possibility of
upgrading conventional gasoil by blending it with GTL Gasoil. Hence, GTL
technology offers the potential to place high quality, gas-derived products
into readily available and high value oil products markets. Access to these
markets is implified and hence made more cost effective by the fact that the
transition from natural gas to liquid is permanent at ambient temperature and
pressure, making transport possible in conventional oil tankers as well as
through the existing land-based distribution infrastructure.
However, marketers are constantly seeking out new, sustainable opportunities for
products that add value to both the producer and the customer. Hence, Shell
introduced its first blend of standard diesel and GTL Fuel as Shell Pura Diesel in
Thailand in 2002. This was followed by the launch of a GTL blend designed for
taxis and commercial vehicles as a clean fuel for the Athens Olympics in 2004. In
marketing these fuels as well as V-Power Diesel, Shell has drawn on the
experience gained from its existing premium fuels business that has seen the
successful launch of a range of customer focused fuels in more than 40 markets.
Marketing future fuels, such as synthetic GTL Fuel, follows a similar approach to
that applied to these advanced premium fuels. The first step is to develop and test
the fuel with leading vehicle and engine component manufacturers. The partners
will then conduct highly 5 visible public trials to demonstrate the benefits of the
product to interested parties such as customers and governments. Of course, the
necessary infrastructure must be put in place to ensure that the fuel reaches
customers at the appropriate price.
In developing a market for GTL Fuel, Shell has been able to draw upon a number
of inherent advantages of the product. The first of these is that it can be distributed
through the existing fuelling infrastructure and used in existing vehicles. That
makes it a more cost-effective option than other alternative fuels for marketers but
also for drivers who can take advantage of a new fuel without having to modify
their vehicles. Independent research carried out by the California Energy
Commission compared the performance of GTL Fuel with other alternative fuels
such as CNG and LPG. It concluded that GTL was the most cost-effective
alternative fuel for the replacement of petroleum based products and reducing local
emissions. The flexibility of GTL Fuel is another attractive feature for the market.
In particular, the use of GTL in a blend opens up growing opportunities in the light
of the increasing use of diesel-powered vehicles. In France, diesel vehicles now
make up 70 per cent of new car registrations and total sales of diesel passenger cars
in western Europe are now outstripping those for gasoline powered cars for the
first time, with the trend set to continue.
However, the key advantage offered by GTL Fuel is the reduction it offers in local
emissions. This is attractive to policy makers, drivers and the inhabitants of cities
and traffic-congested areas. GTL Fuel significantly reduces local emissions of
particulates, nitrogen oxide, carbon monoxide, and hydrocarbons. Furthermore,
independent studies show that carbon dioxide emissions from GTL Fuel
are currently comparable with refinery-produced diesel on a life cycle assessment
basis. Considerable R&D is being invested to increase GTL plant efficiency
targeting up to 30% reductions in CO2 emissions, whilst improvements in engine
technology will lead to further gains. Already, GTL Fuel can offer improved
engine efficiency from minor adjustments to ignition timing and compression ratio
designed to maximise the benefit of its high cetane number. All of which means
there is potential to improve emissions performance still further.
The most rewarding part of our GTL Fuel marketing activities is the favourable
response from our customers. Indeed, in the markets where GTL Fuel blends have
been launched, the product has proved attractive to customers and has rapidly
gained market share. Customer research has shown that consumers react positively
to the synthetic fuels story, appreciating its innovative nature, its emissions
performance and the fact that they are at the leading edge of a very new
development in the fuels market. GTL Fuel, neat or blended with conventional
diesels, has been tested in close cooperation with the diesel experts from the
automotive industry who are convinced that it enables better performance, fuel
economy and reduced local emissions.
2.4 TESTING GTL ON THE ROAD
Shell has been conducting a number of trials using GTL Fuel in some of the major
cities around the world. These trials have helped to demonstrate the advantages of
the fuel in practice and to raise awareness amongst both governments and the
public. Each of the trials have tested GTL Fuel in different conditions and in
different vehicles, (cars, buses and lorries), and the results of all these trials to date
have shown significant reductions in particulate emissions, along with decreases in
hydrocarbons and carbon monoxide, at the same time as maintaining engine
performance.
Emissions benefits were seen in a trial with 25 Volkswagen Golf cars launched in
Berlin by former German Chancellor Schroeder. Results showed that neat GTL
Fuel used in unmodified cars provided reductions of 26% in particulates, 63% in
hydrocarbons, 6% NOx and 91% carbon monoxide even compared with so-called
‘sulphur free’ diesel. In June 2005, Shell and Volkswagen were jointly awarded
one of the top honours in the world for advancements in automotive engineering
and fuel development, the coveted Prof. Ferdinand Porsche prize, following their
partnership in the successful GTL Fuel trial conducted in Berlin. In London, ten
Toyota cars operating on 100 % GTL Fuel were loaned to voluntary organisations
to use in their every day activities. The vehicles were also equipped with Toyota’s
D-CAT emission reduction technology as part of a joint Toyota and Shell research
programme that is developing new 6 vehicle and fuel technologies. This work
underlines the way that the advantages of GTL Fuel can be leveraged further when
combined with advanced engine technology.
A year-long trial in California, tested GTL Fuel in six trucks with conventional
engines as they delivered bottled water. The results showed that even without
particulate filters, nitrogen oxide emissions were reduced by 16 % and particulates
by 23 %. Similar reductions have been seen from trials of GTL blends in heavy-
duty lorries and diesel-hybrid buses in Japan. In Shanghai, an Audi A8 using 100
% GTL Fuel was one of the class winners of the Michelin Bibendum vehicle
challenge. The trial involved a series of driving and emission performance tests
carried out on the Formula One race circuit. This provided a powerful illustration
to the wider public of the high performance that can be achieved using GTL Fuel.
In China, Shell has entered into cooperation with three prestigious universities with
the aim of demonstrating the benefits of GTL Fuel and helping find clean energy
solutions for Shanghai.
2.5 AN ATTRACTIVE, COST EFFECTIVE ROUTE TO LOW EMISSIONS
It is, however, important to be clear that in the short to medium term, GTL Fuel
production will be small, up to 3-4% of total diesel demand by 2020, so that crude
oil will remain the main source of transport fuel. This means it will be important to
target particular markets where GTL Fuel’s emissions performance can offer the
most significant advantages. As the world’s population grows and with it the
demand for mobility, as exemplified in China, it is clear that the world’s major
cities will face increasing challenges in dealing with local air pollution. There are
currently 25 cities, with populations of more than 10 million people (so called
mega cities), and 68 more with populations of over 4.5 million. Rapidly expanding
mega cities, such as Shanghai and Beijing, currently have high transport emission
levels causing significant local air pollution, as well as growing populations and
old diesel fleets. GTL Fuel offers one pragmatic way of helping those cities to
meet the challenges of providing more sustainable transport. In particular, the
flexibility of GTL Fuel means that we could envisage a situation where vehicles
could use GTL Fuel in urban driving conditions or on congested highways and
then revert to advanced diesel in rural areas where air pollution is less of a
problem. There is real potential to realise further advantages from GTL by working
in collaboration with engine manufacturers. Shell is part of a project supported by
US Department of Energy that is working to develop a clean combustion engine
with DaimlerChrysler, whilst in Japan the government is supporting a project to
explore the potential for dedicated GTL engines. While limited GTL Fuel is
available now, its increasing availability will be one element in a rapidly
changing and increasingly diverse fuels market. Those changes are being driven by
concerns about energy security, environmental impact and economic development
and GTL Fuel can play a role in addressing each of these issues. On energy
security, GTL offers governments the chance to diversify their energy supplies and
in particular to reduce the dependence on oil. With regard to environmental
concerns and stricter legislation, both consumers and governments want cleaner
fuels, and the low emissions performance of GTL Fuel presents both groups with a
very attractive option, particularly in larger cities.
With more volume available in more markets in the short to medium term, GTL
can also be seen as part of the synthetic fuels continuum, providing flexible
feedstock options such as biomass (BTL) and coal (CTL) as well as natural gas.
BTL can significantly reduce CO2 (by up to ~80%), and CTL can exploit vast coal
resources but requires CO2 management. Identical synthetic products are produced
from these feedstocks that can enable the development of advanced engines to
fully exploit the homogenous chemistry and premium properties of GTL Fuel.
Governments and car manufacturers are showing growing interest in synthetic
fuels as a step towards the longer-term goal of high efficiency, low emission
hybrid technology or renewable fuels.
To governments, GTL Fuel offers the potential for cost-effective emissions
reductions using existing infrastructure and without the need to replace vehicles or
make expensive conversions to other alternative fuels such as CNG. To consumers,
it provides a premium fuel, with improved performance 7 including reduced noise
levels and emissions, as well as the chance to use an innovative fuel in both heavy-
duty buses and trucks and high performance diesel cars. Better still, it can be used
in existing engines and refuelling infrastructure. All these reasons make GTL an
attractive gas conversion technology to resource holders, producing a range of
products that are attractive to customers. The technology has been proven over a
decade of operations, whilst the products have been demonstrated in many
countries and vehicle types. This means Gas to Liquids provides an opportunity for
significant business growth in the fuels market but also a pragmatic and cost-
effective way of meeting the challenge of sustainable mobility.
The 2006 Le Mans race will see Shell V-Power Diesel fuel technology put to the
test alongside some of the world’s fastest gasoline-driven cars for what is widely
regarded as the world’s toughest motor race. Le Mans is considered by many as the
ultimate challenge, where blistering power, engine endurance and unrivalled fuel
economy are critical to success. The GTL industry has come a long way. Audi
have won 4 of the last 5 Le Mans races and the prospect that they may add another
success with a diesel engine car, fuelled by a GTL blend, is exciting for all those
involved in both the GTL and the Motor industries.
CHAPTER THREE
3.0 METHODOLOGY
Natural gas has played an important role in the supply of daily energy requirements
for industrial and domestic use. The total global annual gas consumption is
forecasted to rise to 2.9 trillion cubic metres by 2015 accounting for approximately
27% of the total primary energy supply. Most of this gas is supplied to the ultimate
consumers by pipeline distribution. However, a considerable portion of the world
natural gas reserves fall into the category termed as ‘stranded’ where conventional
means of transportation via pipeline is not practical or economical. ‘Stranded’
gas reserves are either located remotely from consumers or are in the region where
the demand for gas is limited. The drive to monetize large stranded gas resources,
coupled with prudent utilization of gas resource and environmental considerations
lead to the developments in Liquefied Natural Gas (LNG) and in Gas-to-Liquid
(GTL) Fischer-Tropsch technologies. The former is essentially a physical change
process converting natural gas to liquid for ease of transportation while the later is
a chemical change process yielding naphtha, transportation fuels and speciality
chemicals such as lubes and basestocks. The use of LNG and GTL products offer
environmental benefits over other conventional fuels such as coal and products
derived from crude oil. LNG and GTL serve entirely different energy markets with
different marketing systems, policies and strategies. The comparison between LNG
and GTL is the most prominent debate for resource owner, developer and investors
alike. LNG has the obvious advantage of being established for the past 40 years
and has to-date enjoyed robust growth and has an excellent safety record. GTL on
the other hand is an emerging technology on the verge of demonstrating,
commercial viability, technology robustness, and safety performance. LNG trade
to-date has been dominated in the Far East primarily due to the proximity of the
suppliers and consumers with Japan and Korea accounting for the lion’s share of
the market. The birth of the North American and European market is about to
radically change the LNG trade fundamentals bringing about a new era for LNG.
Until recently the viability of GTL did not look promising when compared to
alternative
transportation fuels production from crude oil refining. Developments in GTL
technology and stringent environmental specifications for transportation fuel oils
have paved the way for GTL projects. The use of GTL technology spearheaded by
Qatar is on the verge of commercial viability and has the potential for becoming a
prominent alternative for stranded gas monetization in the next two decades.
3.1Technical developments of GTL and LNG
The LNG process first involves a gas treatment plant for removal of acid gas
(sulfur, carbon dioxide), water, and other contaminants. The gas is then cooled to
separate the heavier hydrocarbons such as C3, C4, and C5+ components. These
heavier components are then fractionated to produce C5+ and Liquefied petroleum
gas (LPG) products. The purified gas is then liquefied in cryogenic exchangers at a
temperature of -162 °C. LNG, occupies only 1/600 of its original volume in the
gaseous state, is then stored in LNG tanks prior to shipping to market in heavily
insulated tankers and regasified for use in conventional gas markets such as power
generation and domestic applications (Yang and Wang, 2005). A typical
LNG process is as Fig. 3.1.
Fig 3.1 The schema of a typical LNG process.
Like the LNG process, the GTL process also starts with a gas plant for removal of
sulfur, carbon dioxide, water, other contaminants and heavier hydrocarbon
components. However, unlike the LNG process, which is a simple physical process
to liquefy natural gas at a cryogenic temperature, the GTL process involves several
complex chemical reactions. A GTL unit comprises of three core technologies:
synthesis gas (syngas) manufacture, Fischer-Tropsch (F-T) synthesis and
hydrocracking (Hu et al, 2006; Fleisch et al, 2002; Heng and Idrus, 2004;
Bakkerud, 2005; Sie, 1998). In the syngas manufacture process, the purified gas is
converted to syngas by partial oxidation, steam reforming, or a combination of the
two processes. The syngas is predetermined with a mixture of hydrogen and carbon
monoxide with a 2:1 ratio of hydrogen to carbon monoxide as the feedstock of
Fischer-Tropsch synthesis. The syngas is then converted to paraffinic
hydrocarbons in a F-T Reactor with the use of cobalt or iron based catalyst. This
stage is the key to the commercial success of the GTL process, and high yields of
desirable middle distillate products are essential to lower unit cost. In the final
stage of the GTL process, the raw F-T hydrocarbons are subsequently upgraded to
final products by using conventional refinery processes: wax hydrocracking,
distillate hydrotreating, catalytic reforming, etc. The primary products include
naphtha, and transportation fuels such as diesel and jet fuels. GTL is also an
efficient process for producing high quality lubes, waxes and white oils, which are
utilized in the food and pharmaceutical industry. A simplified GTL-F-T process is
shown in Fig. 3.2.
Natural gas
Acid gas removal
De-hydration
Propane pre-coolingLPG
Liquefaction End Flash
C5+
LPG
LNG
Fig 3.2 The overall Schema of a GTL process.
Although long achieving technical success, GTL has not been economically
competitive, and LNG has been actually the only commercial option for the owners
of “stranded” gas, until recently. Today we see a resurrecting second generation
GTL process using low-temperature F-T conversion as a result of abundant gas
supply and strong need of high quality transportation fuels. The increasing
Air dzzcxzcx AirSeparation
AirNatural gas
Synthetic gas production
O2
Catalytic Partial OxidationSteam
H2S, CO2, H2O, others
C5+, LPG & (Ethane)
Hydrogen
Steam
F-T synthesis
Steam
WaterAqueousOxygenate
CH4
Fischer-TropschSynthesis
Steam reforming
Product Recovery
Fuel Gas (LPG)
C2H4 (polyethene)
C3H6 (polypropene)
Product Grade-UpHydrocarbonUpgrading:HydrocrackingIsomerizationCat. ReformingAkylation
LPG (Pentene/hexene)
Neptha
Kero/Diesel
Waxes
Airseparation
Gas Processing + Pre-treat
Steamreforming
efficiency of the GTL process and the ability to build bigger plants of commercial
scale based on operational experience make GTL an attractive alternative to LNG
for the gas owners to monetize the “stranded” gas resources. However, the GTL
process is still in its infancy, and only Shell SMDS and Sasol Synthol are in
commercial operation. The other processes, such as Rentech, Exxon Mobil AGC-
21 and Syntroleum are still in the demonstration stage. Therefore, GTL production
has significantly larger technical risk than LNG production at present.
3.2 Products and market
The primary market for LNG is power generation, industrial fuel and domestic and
commercial heating and air-conditioning. Since its inauguration in 1964, LNG has
consistently increased its share in world’s natural gas trade. The total LNG trade is
8×104 tonnes in 1964 and increased to 1.318×108 tonnes in 2004 with an annual
increase rate of 20.34%. If we just take the development from 1994 to 2004
into account, the annual increase rate is also as high as 7.31%. The portion of LNG
trade in the world total natural gas trade increased from 0.3% in 1970 to 26.2% in
2004. According to BCC (Business Communication Company, USA), the total
LNG trade will reach 2.50×109 tonnes in 2010 (Zeng, 2006). Before 2000, the
world LNG trade was in a period of short-term balance. However, with the strong
rise in the price of crude oil from the winter of 2000, the world LNG demand has
grown rapidly and the demand of LNG exceeded the supply from 2004. As the
three major markets of LNG, the import of Asia, European, and North America
was 9.23× 107 t, 3.74×107 t, and 1.36×107 t in 2005, and was increased by 9.6%,
25.9%, and 21.4% compared to that in 2004, respectively. This supply/demand
imbalance combined with high oil price caused a significant rise of LNG price for
long-term contracts and on the open market. The FOB price of LNG contract
signed in 2003 was less than $3.5/MMBTU (1 MMBTU = 28 m3), whereas the
price increased to $5/MMBTU at the end of 2005, and $6/MMBTU in 2006 (Zeng,
2006; Zhang and Pang, 2005; Wang, 2005). Due to the large growth potential in
the LNG market, the supply-demand balance for LNG in the short to medium term
is forecasted to remain very competitive. However, the world natural gas resource
is abundant and the high price of LNG has attracted aggressive investment in LNG
facilities, which is estimated to be over $67 billion from 2005 to 2009, and the
potential supply of LNG will exceed demand. The imbalance situation of LNG
supply versus demand is forecasted to change after 2010 and the prices of LNG
would possibly decline in a long-term prospect. Therefore, many natural gas
owners are devoting a lot of effort to develop other competitive projects except
LNG facilities and gain market share even while the LNG prices remain fairly
aggressive. The pricing mechanism for LNG is usually based on long-term
commitment by the supplier and consumer. Via long-term contract, the suppliers
can reduce the high risk for building new LNG facilities and the buyers can get
guaranteed and reliable LNG supply. Therefore, most of the LNG trades are long-
term contracts of more than 20 years and the actual price adjusts according to the
crude oil price with a floor and a ceiling (Zhang and Pang, 2005). GTL plants are
capable of producing a slate of products with highly desirable properties, including
lube base stocks, diesels/kerosene, petrochemical naphtha and waxes as Fig. 3.2
shows. These products meet or exceed virtually all product requirements and,
therefore, are fully compatible with petroleum-derived products. F-T diesel is
characterized by low sulfur (~3 ppm), low aromatics (~1%), a high cetane
number (~70), and excellent cold flow properties (Cold Filter Plugging Point,
CFPP < –10 °C). These properties make GTL diesel significantly different from
diesel derived from crude oil, which is under increasing environmental pressure to
reduce its sulfur, nitrogen, olefins, aromatics and metals content. GTL naphtha due
to its high paraffin content is an excellent feedstock for petrochemical plants.
These environmental benefits of the GTL products make the GTL technology
important for the supply of low sulfur, low aromatic transportation fuels (Yang and
Wang, 2005; Fleisch et al, 2002; Heng and Idrus, 2004; Bakkerud, 2005; Sie,
1998). The primary market for GTL products is the ever increasing transportation
fuels sector. The current world demand for diesel derived from crude refining is
enormous at around 28 MMbpd (1 MMbpd = 5×107 t/a). GTL is considered a very
small player in this vast diesel market and such market potential for GTL products
can essentially be considered unlimited. The high-quality of GTL diesel exceeds
all anticipated future diesel requirement anywhere in the world. More important,
the GTL fuels work well in existing infrastructure and in standard diesel fuel
engine technology. This is not usually the case for many other alternative fuels that
require customized vehicle modifications. A smooth transition can significantly
increase the speed of introducing GTL as an alternative fuel into the market. Given
this market potential and superior product quality, it is perhaps only a matter of
time before F-T-GTL becomes a formidable industry (Patel, 2005).
Unlike LNG, GTL products are commodities that do not require long-term
purchase agreements and can be sold in the open market. Although GTL diesel is
environmentally superior to diesel derived from crude oil, the pricing mechanism
for the GTL products will essentially be similar to that of the refi ned products,
which is essentially benchmarked on crude oil prices (Patel, 2005; Yao, 2005).
3.3 Capital costs
The total capital cost for a typical full chain LNG facility processing 1 BSCFD
(103.36×108 m3/a) is estimated at around 2.4 billion US dollars, which can be
conveniently divided into three units: liquefaction facilities (gas plant, liquefaction
process, utilities, and offsites), transportation (mainly the LNG ships), and
receiving regasification terminals. Among them, the cost for the liquefaction plant
is about 52% of the total cost, the cost for the receiving regasification terminals
is about 16%, and the LNG ships is about 32%. During the past ten years, the
typical cost for liquefaction has decreased by 25%-35%; the cost for transportation
has decreased by 20%-30%, whereas the decrease of the cost for regasification
is much slower.
Similarly, the capital cost of a GTL processing 1 BSCFD is estimated at around $
2.5 billion, which can be divided into the following units: gas plant, syngas unit
including the air separation unit, Fischer-Tropsch unit, product upgrading unit,
other processing units, utilities, and offsites. Significant developments in GTL
technology have been made in the past several years and are still ongoing and it
very likely to see a continuous downtrend of the overall capital cost of GTL in the
near future.
Both GTL and LNG require large capital investment, and the magnitude of capital
investment is similar for GTL and a full chain LNG facility processing equal
amount of natural gas feed. However, the capital costs for LNG production
facilities alone are much less than those for GTL because LNG importers usually
take the responsibility for investing LNG ships and regasification terminals. For
LNG and GTL facilities, the bigger the scale, the more the profit. However,
several companies such as Syntroleum and Exxon Mobil have developed small-
scale GTL technology that requires relatively smaller capital investment.
Therefore, the GTL production is more fl exible and can easily be regulated
according to the marketing and international circumstances, making GTL more
suitable for small “stranded” natural gas storages (Hu et al, 2006; Yao, 2005; Han
et al, 2006; Antari and Mokrani, 2002; Qian and Zhu, 2007 ).
3.4 Economic evaluation
The economic evaluation of GTL versus LNG can be conducted in terms of
production costs and product value (Patel, 2005). Table 1 presents the costs of
producing GTL transportation fuels and LNG at a natural gas price of
$7.0-11.0/MMBTU and refinery fuels at a crude oil price of $80-120/bbl (1 bbl =
0.14 tonnes). Since one barrel of GTL product requires approximately 10 MMBTU
of natural gas, the comparison of the production costs in Table 1 is made at a
standard of 10 MMBTU natural gas feed stocks. Although the operating and
capital costs are higher for GTL than for refinery products, the overall cost of
producing diesel from gas by GTL is similar with that from crude oil by refinery.
The cost of LNG production corresponding to 10 MMBTU of natural gas is
estimated to be $80-125, which is slightly smaller but close to that of GTL.
Therefore, the profitability
of the two gas monetizing options is essentially governed by the final value of the
products.
Table 3.2 compared the production value (revenue) generated from the same
quantity of gas (10 MMBTU) between LNG and GTL. If the typical current market
price of the GTL diesel is assumed as $120-160/bbl and one barrel of GTL product
requires approximately 10 MMBTU of natural gas, the ultimate production value
of the natural gas resource is $12.0-16.0 per MMBTU for GTL. If the typical
current market price of LNG is $14.0-18.0/MMBTU, taking account of the
conversion efficiency, the ultimate production value of the natural gas resource can
be calculated as $12.32-15.84 per MMBTU for LNG. As the production cost, the
product value of the natural gas resource appears to be very similar based on the
above pricing assumptions for the two systems.
Table 3.1 Production cost of GTL transport fuel, Refinery fuel and LNG.
Facility GTL Refinery LNG
Natural gas (10 MMBTU) $70-110 -------- $70-110
Cash costs Crude oil (1 Barrel) --------- $80-120 -------
Operating costs $6-8 $2-3 $2-3
Capital costs $9-14 $4-7 $8-12
Total cost of product $85-132 $86-130 $80-125
Table 3.2 Production value of GTL and LNG.
Facility GTL LNG
Market price product $120-160/bbl $14.0-18.0/MMBTU
Conservation efficiency 60% 88%
Feed 10 MMBTU 1.14 MMBTU
Production value of feed $12.0-16.0 $12.32-15.84
The above analysis suggests comparable investments for both GTL and LNG. The
long term pricing mechanism for LNG is not conducive to maximize the resource
revenue. The GTL product value on the other hand is vulnerable to crude oil
prices. However, due to the high quality of GTL products, whose value is at the
uptrend, under the ‘normal’ crude oil pricing range GTL appears to offer better
revenue for the resources (Smith, 2004; Yao, 2005; Kashav and Basu, 2007). Table
3.3 is the economic analysis of GTL and LNG by Syntroleum Company for the gas
resources at Yamal peninsula, which forecasts similar investment and a fairly
higher profitability of GTL for large-scale natural gas reservoirs (Qian and Zhu,
2007). Although the analysis of Table 3.3 is made in 2004 with the price for crude
oil and natural gas increasing significantly during the past several years, the
forecast still works reasonably due to the similar scale increase of crude oil and
natural gas price.
Table 3.3 Economic analysis of GTL and LNG for large-scale natural gas reservoirs.
GTL LNG
Product price $220/ft $140/t
Sale volume 550*104t 640*104t
Facility investment $3.4 billion $2.3 billion
Oil tanker investment $0.3 billion $1.0 billion
Total investment $3.7 billion $3.3 billion
Market location Rotterdam Zeebrugge
Market Distance 4000km 4000km
Investment repayment rate 15% 12%
CHAPTER FOUR
4.0 CONCLUSION
In summary, GTL F-T technology is beginning to show commercial viability,
whereas LNG has been well established. A GTL facility is more complex, has
lower plant efficiency and is more expensive than an LNG facility. However the
full chain capital expenses of both GTL and LNG are comparable. Due to the
similar capital investment the decision to invest in LNG or GTL from a resource
owner’s perspective can be challenging. Besides the capital, other factors, such as
technology risks, plant availability, local market, overall company strategy and
political consideration are also important in the decision-making. GTL and LNG
serve different energy markets and both are attractive for monetization of stranded
gas reserves. GTL products, dependent upon the crude oil price, exhibit slightly
higher value per MMBTU than LNG. Technological improvement and compelling
investment from the world’s major oil companies suggest that the GTL industry is
likely to expand rapidly over the next decade and will develop into a significant
commercial factor in world energy markets over the next few years. More GTL
means that less LNG will be available on the world market, slowing the
development of competition and resulting in higher prices and less available supply
of LNG, potentially altering LNG’s projected role in the world’s natural gas
market.
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