Department of Petroleum Engineering and Applied Geophysics
TPG4140 Natural Gas
South Caucasus Pipeline
Technical Details and Political Background
Valentina Parra Gómez
Marcos Herreros Carballo
Jaime Hortelano García-Borreguero
Michael Storch
Andreas Waldraff
Trondheim
November 2008
1
Abstract
The Caspian Sea is one of the most important regions in the world for petroleum
resources and a major supplier for oil and gas to European markets. The transport of these
resources to the customers is carried out by pipelines. Today the biggest pipelines are the
Baku-Tiflis-Ceyhan-Pipeline transporting oil from the Caspian Sea to the Mediterranean Sea
and parallel to it the South Caucasus Pipeline supplying natural gas to markets in Georgia and
Turkey. But there are already plans of building more pipelines connecting the Caspian region
to Europe.
This report deals with the South Caucasus (natural gas) Pipeline. It pictures the
pipeline in technical detail including production, processing and transport of the gas.
Furthermore, it describes the economical and political issues concerning of the pipeline in the
past, the present and in the future. More than ever gas pipelines are getting more and more
important due to shrinking fossil resources and environmental issues all over the world.
2
Index
1 Introduction ............................................................................................................................. 6
2 Survey...................................................................................................................................... 7
2.1 Purpose of the pipeline ..................................................................................................... 7
2.2 Description of the pipeline ............................................................................................... 7
2.3 Owners .............................................................................................................................. 8
2.4 Design and construction of the pipeline ........................................................................... 9
2.5 Other pipelines in the South Caucasus area.................................................................... 11
3 Political situation ................................................................................................................... 12
3.1 General overview ............................................................................................................ 12
3.2 Political circumstances ................................................................................................... 13
3.2.1 Interests and Purposes .............................................................................................. 13
3.2.2 Supply with raw gas ................................................................................................. 14
3.2.3 Conflict about influence ........................................................................................... 14
3.3 Examples for using energy as a political factor .............................................................. 16
3.3.1 Oil crisis in 1973 ...................................................................................................... 16
3.3.2 Russian – Ukrainian gas conflict 2005 .................................................................... 16
3.3.3 Russian – Belorussian energy conflict 2007 ............................................................ 16
3.3.4 Nord stream Pipeline ................................................................................................ 17
3.4 Local conflict in the Caucasus ........................................................................................ 17
4 Reservoir and production ...................................................................................................... 19
4.1 Shah Deniz gas field ....................................................................................................... 19
4.2 Production and development .......................................................................................... 20
5 Processing.............................................................................................................................. 21
5.1 Sangachal terminal ......................................................................................................... 21
5.2 Natural gas processing .................................................................................................... 22
5.2.1 Process steps ............................................................................................................ 22
5.2.3 Acid gases ................................................................................................................ 26
5.2.4 Nitrogen ................................................................................................................... 26
3
5.2.5 Mercury .................................................................................................................... 28
5.2.6 Natural Gas Liquids (NGL) ..................................................................................... 28
6 Transport ............................................................................................................................... 29
6.1 Gas pipelines................................................................................................................... 29
6.2 Pipes................................................................................................................................ 30
6. 3 Compressor Stations ...................................................................................................... 31
6.4 Metering Stations ............................................................................................................ 32
6.5 Valves ............................................................................................................................. 32
6.6 Control Stations .............................................................................................................. 32
6.7 Pipeline Inspection ......................................................................................................... 32
7 Simulation ............................................................................................................................. 33
7.1 Given data ....................................................................................................................... 33
7.2 Approach for Simulation ............................................................................................... 36
7.3 Results ............................................................................................................................ 38
8 Conclusion ............................................................................................................................. 40
References ................................................................................................................................ 40
4
List of tables
Table 1 Summary of flow rates ...............................................................................................28
Table2 Gas composition ..........................................................................................................28
Table 3 Gas pump stations .......................................................................................................29
Table 4 Off-take fuel stations ..................................................................................................29
Table 5 Data .............................................................................................................................32
List of figures
Figure 1 BTC and SCP pìpelines in the South Caucasus Area
Figure 2 Owners of SCP
[1]
[1]
............................................. 7
........................................................................................................ 8
Figure 3 Digging for the pipe and the block valve station [1] ................................................... 10
Figure 4 River crossing [1] ........................................................................................................ 10
Figure 5 Construction of the pipe [1]......................................................................................... 11
Figure 6 Other pipelines in the South Caucasus area [2] ........................................................... 11
Figure 7 Political map of the South Caucasus [3] ..................................................................... 17
Figure 8 Flow diagram of natural gas processing [4] ................................................................ 23
Figure 9 Flow diagram of water removal [4] ............................................................................. 24
Figure 10 Flow scheme of a typical amine process [4] ............................................................. 26
Figure 11 Flow scheme of a nitrogen removal [4]..................................................................... 28
Figure 12 Flow diagram of NGL removal [4] ........................................................................... 29
Figure 13 Moody friction factor chart (Moody 1944) [6].......................................................... 31
Figure 14 HYSYS Flow Sheet ................................................................................................. 36
Figure 15 Elevation profile of SCP [5] ...................................................................................... 37
Figure 16 Pressure Drop along SCP [5]..................................................................................... 38
Figure 17 Compression power required along SCP [5] ............................................................. 39
5
1 Introduction
In most of the works dealing with the South Caucasian Pipeline this pipeline is just
mentioned in larger context together with other pipelines in the Caucasus as a part of the local
transport net for energy. There are hardly papers concentrating just on this single pipeline and
that’s why this project describes the South Caucasus Pipeline in its course and construction.
Generally information about the pipeline itself isn’t connected to other important
issues like reservoirs, production or further treatment of the gas. This work shall provide an
overview over the whole chain from the reservoirs until the delivery of the treated sales gas to
the customers. Therefore the gas field from which this pipeline is fed, the production and the
necessary processing of the produced gas shall be discussed in this work.
Due to the fact that this pipeline already exists and is operated it is quite interesting
what the operation conditions are. The main aspect in this case is the pressure drop along the
pipeline which has to be equalized in several pumping stations. Because of that, calculations
with the simulation tool has been done to get simplified characteristics of the pressure drop in
this pipeline and with this, simplified statements concerning the needed compression power
could be made. But not only technical details shall be discussed also political circumstances
and tensions located in the area where this pipeline is built are regarded. A possible lack of
security and stability could affect the transport of gas through this pipeline and could have
consequences in the future not only for this region but also for Europe’s gas supply because
the South Caucasus Pipeline is a first step in a possible pipeline track supplying Europe with
Caucasian gas.
6
2 Survey
2.1 Purpose of the pipeline
The expansion of natural gas production is currently underway in Azerbaijan,
particularly with the development of the Shah Deniz field. The domestic demand for gas in
the Caucasus and Central Asia is mostly met by current supplies and is unlikely to grow
significantly in the near future. The Government of Azerbaijan negotiated a gas sales and
purchase agreement with the Government of Turkey to supply Shah Deniz gas to Turkey by
the end of 2005 and the South Caucasus Pipeline (SCP) project has been designed to facilitate
gas transport. At full capacity, and after additional stages of development, the pipeline was
designed to export up to 16bcm/year from the existing Sangachal Terminal near Baku in
Azerbaijan, through Georgia to the Georgian–Turkish border. The SCP links up with a
pipeline being constructed within Turkey to transport the gas to Erzurum, where it enters the
domestic supply grid.
The first aim of pipeline is to supply Turkey and Georgia. As a transit country,
Georgia has rights to take 5 % of the annual gas flow through the pipeline as a tariff and can
purchase a further 0.5 billion cubic meters of gas a year at a discounted price. In longer
perspective South Caucasus Pipeline will supply Europe with Caspian natural gas through the
planned Nabucco, Turkey-Greece, Greece-Italy pipelines.
2.2 Description of the pipeline
Figure 1 BTC and SCP pìpelines in the South Caucasus Area
[1]
7
The 42 inches (1,070 mm) diameter gas pipeline transports gas from Sangachal in
Azerbaijan to markets in Georgia and Turkey. It reaches 690 km long, of which 445 km is laid
in Azerbaijan and 245 km in Georgia. It reaches 2400 m as it crosses the South Caucasus. The
initial capacity of the pipeline is 8.8 billion cubic meters (bcm) of gas per year, and after 2012
its capacity could be expanded to 20 bcm per year. The pipeline has a potential of being
connected to Turkmen and Kazakh producers through the planned Trans-Caspian Gas
Pipeline.
2.3 Owners
The pipeline is commissioned by a consortium led by BP and Statoil. The shareholders
of the consortium are:
 BP (UK) 25.5 %
 StatoilHydro (Norway) 25.5 %
 State Oil Company of Azerbaijan (SOCAR) (Azerbaijan) 10 %
 LukAgip, a joint company of Lukoil and Eni (Russia/Italy) 10 %
 TotalFinaElf (France) 10 %
 Oil Industries Engineering and Construction (OIEC) (Iran) 10 %
 Türkiye Petrolleri Anonim Ortaklığı (TPAO) (Turkey) 9 %
The technical operator of pipeline is BP, which is leading the design and construction
phase of the Project and the commercial operator is Statoil. The total investments in the
pipeline are 1330 million $.
StatoilHydro
25.50%
BP
25.50%
AzSCPC
10%
Total
10%
Lukoil
10%
Nico
10%
TPAO
9%
Figure 2 Owners of SCP
[1]
8
2.4 Design and construction of the pipeline
SCP has been constructed in the same corridor as the BTC (Baku-Tbilisi-Ceyhan oil
pipeline) in order to minimize the environmental and social impact, using the same integrated
project team. An experienced international contractor, under close supervision of the SCP
partners management team, carried out construction of the pipeline. At peak during the
construction phase of the combined projects some 22,000 people were employed.
Within Azerbaijan, the SCP pipeline system will principally include:

Gas supply infrastructure and pig launching facilities at the Sangachal
Terminal

Valve stations

A cathodic protection (CP) system

A fibre optic communications system
In the design of a long distance pipeline many factors must be considered: the nature
and volume of the gas to be transmitted, the length of the line, the type of terrain to be
crossed, and maximum elevation of the route. After a gas compression station is located and
sized, the gathering system is designed. This involves the location of the wells, the ability of
right of way, the amount of gas to be handled, the distance to be transported, and the pressure
difference between the field and the main transmission line.
The gas wells are generally located in groups around a geological structure or within
the defined limits of a pool or gas reservoir. In a new field, the gather system must be large
enough to handle the production of additional leases. The gathering system is made up of
branches that lead into trunk lines. The trunk line is small at the most distant well and, as
more wells along the line are attached to it, the line must be larger to accommodate the greater
volume of gas. In addition to the gathering system and major trunk pipelines, there is also a
network of smaller diameter feeder and transmission mains that may carry gas to
consumption.
9
Figure 3 Digging for the pipe and the block valve station [1]
Initially the pipeline construction corridor was marked, prior to clearing and levelling.
Generally topsoil is stripped and stored to one side of the corridor, and separately from
subsoil. The pipeline trench is excavated to approximately 2.2m, allowing the pipeline to be
buried with a minimum depth of cover of 1m. Deeper burial are required at river, road, rail
and other crossings.
Figure 4 River crossing [1]
Pipe sections are transported to the construction corridor by truck and laid end-to-end
alongside the open trench. The pre-coated pipe sections are then welded together and a further
protective coating applied to the welded joints. The coating is tested to ensure it will provide
adequate corrosion protection before the pipe is lowered into the trench.
The trench is then filled with the material taken from the trench, in the reverse order to
which it was excavated. The cover material is compacted to reduce the risk of future
settlement and erosion.
10
Figure 5 Construction of the pipe [1]
The construction corridor and all other project areas will be reinstated, either fully or
using interim measures if required for imminent gas pipeline construction. Reinstatement will
include erosion control measures and re-vegetation. The integrity of the pipeline is tested by
filling discrete sections with water and increasing the pressure. The construction of the
pipeline required also a number of temporary facilities, including construction camps for
workers and pipe storage yards.
2.5 Other pipelines in the South Caucasus area
Figure 6 Other pipelines in the South Caucasus area [2]
11
The Baku-Tbilisi-Ceyhan (BTC) pipeline runs parallel to the South Caucasus Gas
Pipeline. It is a 1,768 kilometres crude oil pipeline from the Azeri-Chirag-Guneshli oil field in
the Caspian Sea to the Mediterranean Sea. It connects Baku, the capital of Azerbaijan; Tbilisi,
the capital of Georgia; and Ceyhan, a port on the south-eastern Mediterranean coast of
Turkey, hence its name. It is the second longest oil pipeline in the world after the Druzhba
pipeline. The first oil was pumped from the Baku end of the pipeline on May 2005. From
Sarız to Ceyhan, the Samsun-Ceyhan oil pipeline will be laid parallel to the BTC pipeline.
Other two oil pipelines run from Sangachal Terminal in Azerbaijan: one to Russia (BakuNovorosslysk) and the other one to Georgia (Baku-Supsa).
South Caucasus Pipeline will supply Europe with Caspian natural gas through the
planned Nabucco, Turkey-Greece, Greece-Italy pipelines. The Nabucco pipeline is a planned
natural gas pipeline that will transport natural gas from Turkey to Austria, via Bulgaria,
Romania, and Hungary. It will run from Erzurum in Turkey to Baumgarten an der March, a
major natural gas hub in Austria. This pipeline is a diversion from the current methods of
importing natural gas solely from Russia which exposes EC to dependance and insecurity of
the Kremlin practices. The project is backed by the European Union and the United States.
Construction of pipeline is expected to begin in 2010 and is planned to be finished in 2013.
The company leading the project is OMV from Austria.
3 Political situation
3.1 General overview
The South Caucasian Pipeline is pipeline for transporting natural gas from the Caspian
Sea to Turkey. It runs parallel to the BTC (Baku-Tiflis-Cheyhan) oil pipeline which transport
Caspian raw oil to the Mediterranean Sea. These two pipelines form a new possibility to
supply Europe with energy by bypassing Russia. Although Russia is still the most important
supplier of energy especially natural gas for Europe, those pipelines offer an additional access
to energy not being controlled by Russia. There were several options to lead these pipelines
from the Caspian Sea to Turkey. One possibility was to build them across Iranian territory.
This would have been rather expedient because of the huge oil and gas reserves located in
Iran, which also could have been made available. But this option was politically impossible to
realize because of the Mullah-regime acting in Teheran which shall never be supported in any
way according to western country’s and especially USA’s political doctrine. A second option
was a trace leading through Armenia which would have been the shortest and most
12
economical trace. But this version was refused by Azerbaijan that is still in big trouble with
Armenia what will be discussed further below. That’s why the most expensive and most
complicated to build version had to be realized which leads from Azerbaijan through Georgia
to Turkey where high mountains have to be passed. But anyway these pipelines are the first
transport oil and gas from former soviet countries to the west without participation of Russia
in a big scale. There is indeed an oil pipeline build from Baku to Supsa at the Black Sea in
Georgia but the transport capacity of this pipeline for Western Europe is limited by the size of
the tankers which are allowed to pass the Bosporus and the Dardanelles.
The here discussed gas pipeline started transporting natural gas in May 2006 with a
rate of 6.5 billion m3/a but with the possibility of raising it up to 16 billion m3/a. At the
moment all of the delivered gas is consumed in Georgia and Turkey, according to the operator
British Petroleum (BP) there will be no gas delivery to Europe before 2012. Important in this
context is the planned Nabucco-Pipeline which should realize the transport to Europe after the
South Caucasian Pipeline, but this topic will be discussed further below.
3.2 Political circumstances
3.2.1 Interests and Purposes
The purpose for building the South Caucasian Pipeline is to make the gas reserves
located in the Caspian Sea and also in Iran available for European gas market. The advantage
the gas producing countries especially Azerbaijan with its large gas fields in the Caspian Sea
is to get new customers for its products. Also transit countries like Georgia and Turkey
benefit in form of transit fees and gas supply for themselves from this pipeline. But the largest
interest in installing this pipeline in the South Caucasus has certainly Western Europe.
Western Europe received most of its natural gas from Russia through pipelines leading
through Eastern Europe and because of this west European countries are highly dependant of
Russia’s interests and its energy policy since its gas economy is controlled by the Russian
government. The here discussed South Caucasus Pipeline in combination with the planned
Nabucco pipeline leading from Turkey to Austria provides an alternative in gas supply and
means a step further out of being at Russia’s mercy concerning energy.
13
3.2.2 Supply with raw gas
But this project has still to deal with several problems. There are still some
uncertainties where the needed amount of natural gas should come from. At the beginning of
the project it was planned to receive gas from Azerbaijan’s gas fields in the Caspian Sea as
well as from gas fields from Turkmenistan and Kazakhstan. But there is a subsea pipeline
necessary to make those fields for the South Caucasian and Nabucco Pipeline available what
makes this option quite improbable because of the enormous costs a subsea pipeline would
cause and still unsolved questions of sovereignty concerning the Caspian Sea between the
bordering countries. Another problem is that Russia has already signed several treaties with
Turkmenistan and Kazakhstan in 2007 about delivering their gas to Russia so that there would
be hardly any left for other partners. But Azerbaijani gas alone is not enough to supply the
Nabucco pipeline. There impends also direct concurrence in south Europe because Russia
plans to build in cooperation with an Italian energy company (ENI) a natural gas pipeline
through to Black Sea to Bulgaria from where it should be delivered to Austria and Italy. This
project is known as South Stream pipeline and if it will be realized together with the planned
North Stream pipeline through the Baltic Sea leading to Germany it is rather doubtful if there
is any necessity for a further gas pipeline like the Nabucco. But the Nabucco project is
strongly supported by officials of the European Union to decrease Europe’s dependency of
Russia by creating this bypass. Russia itself tries to thwart such efforts as mentioned by
utilizing the disunity of EU by closing contracts with single EU members concerning energy
supply or blocking the access to necessary resources. If this scenario turns into reality the
South Caucasian Pipeline keeps a local pipeline to supply the southern Caucasus and Turkey
with natural gas what it is at the moment. But even regarded as just affected by local affairs
there this region is a rather complicated and several conflicts have to be considered when one
wants to build and operate a pipeline.
3.2.3 Conflict about influence
The Caucasus is a region of big geopolitical importance and tension. In this region
interests of several local and also global powers converge. On the one hand there is Russia
which regards this region as its historical sphere of interests. On the other hand there are the
former soviet republics especially Georgia which seek a closer position to the west and
especially the NATO countries. The closeness of Iran and Iraq emphasises the conflict
potential of this region. The main reason for the importance of the Caucasus also for western
countries are the huge energy reserves located in the Caspian Sea.
14
Although Western Europe received oil and gas from the Soviet Union during the cold war,
energy from the Caucasus region didn’t play an important role for Western Europe. After the
collapse of the soviet empire and the independence of several soviet republics, this region
moved more and more into the focus of the west and several of these now independent
countries try to free themselves from Moscow’s influence. For western countries like the
members of the EU or the USA this situation was and is still quite complicated to deal with.
On the one hand there is Russia, successor of the Soviet Union and still a powerful factor in
world’s politics and due to its enormous energy reserves essential especially for Western
Europe and therefore decisive and to be considered for any political action in the eastern
sphere. Russia considers the Caucasian region still as their sphere of interests a reacts very
sensitive on every political agitation or engagement of western countries in this region.
Especially an expansion of the NATO in this region would represent a severe threat of
Russia’s interests in its eyes. This could be seen in spring 2008 when the USA wanted to offer
Georgia and the Ukraine negotiations about accession to the NATO but Germany and France
refused their agreement to this plan. One reason for this was that they didn’t want to provoke
Russia which raised severe protest against a further expansion of the NATO until its borders.
On the other hand there is the legitimate claim of Caucasian countries to determine their
position in world’s politics themselves. What is worse in this context, these countries
themselves are partly not able to focus most of their attention to foreign policy because they
had to face severe inner political problems with ethnic minorities, what will be discussed
further below. It is a big challenge for western countries to find a practicable way between
these two poles without getting pocketed by one of the two parties for their interests and to
follow their own interests there. Every investment or other engagement has to be well checked
if there’s nobody’s interests harmed. Simultaneously to this strained political situation energy
supply becomes more and more a source conflicts because of its increasing relevance for the
future. This constellation makes energy and in this context especially natural gas to an
instrument to enforce political purposes.
15
3.3 Examples for using energy as a political factor
3.3.1 Oil crisis in 1973
In autumn 1973 the members of OPEC decided to reduce the amount of raw oil
produced in order to build up pressure on western countries. They should Israel force to reject
from the areas it occupied in the course of the Jom Kippur war 1973. The result was a
temporarily prohibition to drive private car and an expansion of offshore oil production for
instance in the North Sea, to get more independency from Arabic oil.
3.3.2 Russian – Ukrainian gas conflict 2005
Before 2005 the Ukraine was delivered with Russian natural gas to special conditions.
The price for natural gas was far below of that what it has to be paid for it on world’s markets.
In 2005 the Russian gas company Gazprom decided to lift up the price for natural gas on
world market level what would have meant that the Ukraine would have had to pay about four
times more than before. Ukraine referred to existing treaties with Russia and refused to accept
the new conditions. As a consequence Russia reduced to amount of natural gas pumped to the
pipelines leading through the Ukraine on a level which was enough to supply Western Europe
but not the Ukraine. Many politicians regarded to sudden change of Russian energy policy
concerning the Ukraine as a reaction of the changed political circumstances in the Ukraine. At
the end of 2004 a so called “Orange Revolution” took place in the Ukraine where the hitherto
pro-Russian government was replaced by pro-Western forces by huge demonstrations of the
Ukraine population. It is assumed that this energy policy should destabilize the new
government and enforce the pro-Russian party.
3.3.3 Russian – Belorussian energy conflict 2007
Like the Ukraine Belarus was delivered with Russian natural gas to special condition
until 2007. As reward Russia received the major part of Belarus’s income from export duties
of petro products. In 2001 Belarus stopped these payments to Russia and no further
consequences at first. In 2007 Russia demanded the same prices for natural gas from Belarus
like on world markets. To support this demand Russia reduces the delivery rate of oil in
Druzba pipeline leading through Belarus. As a reaction Belarus kept on extracting the amount
of oil they needed so that less oil reached Western Europe as arranged with it which caused
protest of the EU and a serious burden on EU-Russian relationship.
16
3.3.4 Nord stream Pipeline
It is planned to build a subsea pipeline directly from Russia to Germany through the
Baltic Sea. Western Europe’s and Russia’s intention is to get a further supply line for natural
gas to become more independent from transit fees in eastern Europe and possible fluctuation
caused by political crises in transit countries like Belarus or Ukraine as mentioned above. But
this project causes also trouble. Poland for example fears to be encircled by Russia and
Germany; some nationalist polish politicians even compare this project with the Hitler-Stalin
treaty from 1939. They are afraid of being at Russia’s mercy concerning of energy, if Western
Europe could be separately delivered, and they don’t want to abdicate transit fees paid for gas
delivered through existing pipelines at the moment.
3.4 Local conflict in the Caucasus
These four examples shwon above don’t concern the pipeline project discussed in this
work itself but they show that energy and energy supply play increasing role in worlds
politics. The enormous and still growing demand of energy in the Far East, especially in
China, intensify the meaning of energy supply for each industrialized country, increases the
number of possible conflicts and pushes the whole topic on a level of highest importance of
world’s politics. Against this background the regional conflicts in the Caucasus get a global
dimension. Therefore we have now a closer look to south Caucasus region.
Figure 7 Political map of the South Caucasus [3]
17
There are several unsolved conflict located in the Caucasus region which may affect
gas transport through the South Caucasus Pipeline. The most serious one certainly is the
conflict between Georgia and Russia. There are two counties in Georgia, Abkhazia and South
Ossetia, which formal belong to Georgia but don’t acknowledge the Georgian sovereignty.
Many of the inhabitants of these two regions have a Russian citizenship and seek therefore for
unification with Russia. Though Georgia insists on its governance over these two regions
which is affirmed by international law. The given situation is a result of the collapse of the
Soviet Union in the early 90s of the last century. Both counties were parts of the former
Georgian Soviet Republic with a certain level of autonomy. After the declaration of its
independency in 1991 Georgia had to face military attempts of Abkhazia and South Ossetia
supported by Russia to gain complete independency from Georgia itself. After several severe
struggles Georgia could sustain its sovereignty but had to accept UN troops to be stationed as
peace keeping forces which also include Russian soldiers. In august 2008 Georgian military
forces invaded South Ossetia after single combats during the previous month. Russian troops
entered as a reaction to that South Ossetia as well and pushed back Georgian forces deep into
Georgian area. Russian government mentioned the protection of Russian citizens living in
South Ossetia as a justification for its engagement. Because of the threat of being hit by shells
or bombs BP decided to stop transporting gas trough the South Caucasus Pipeline (also the
Western Route Export Pipeline) at the 12th of august as a precaution. This action didn’t cause
that much trouble in the energy supply of Europe but showed in dramatic way what
consequences a regional conflict can have.
Also Russia is affected by separation movements in this region. Separatists in
Chechnya sought for complete independency from Russia. This has already caused bloody
conflicts between them and Russian military forces in the middle of the 90s of the last century
and there is still Russian engagement necessary to maintain calm and peace.
As seen in the map above there is an area located in the middle of Azerbaijan called
Nagorno-Karabakh. The majority of the population living there is Armenian although the area
itself belongs to Azerbaijan according to international law. At the beginning of the 90s of the
last century the conflict between Armenian and Azerbaijani people living there escalated from
single combats to a war taking place from 1992 to 1994 supported by regular Azerbaijani
military forces. The aim of the Armenian party was to gain an independent state and finally
unification with Armenia. After two years of struggle and ethnic banishments of both parties
the Armenian side declared itself independent because of its military success but nobody even
18
not Armenia has confirmed this independency yet. There is a ceasefire since 1994 and but no
final peace treatment has been negotiated which all parties have agreed to.
In the south of Caucasus the settling area of Kurds is located. This ethnic group is
mainly spread over the east of Turkey, north of Iraq and west of Iran. There is also in this
group a huge yearning for an own independent country at the cost of the mentioned countries.
Especially in Turkey where the majority of the Kurdish people are living this demand was
also pursued by armed underground forces calling themselves PKK (labour party of
Kurdistan). Those struggles were mainly fought between 1984 and 1999. But there are still
today single attacks being launched mainly from Iraqi territory.
These four examples show quite well the explosive and politically rather instable
conditions in which the South Caucasian Pipeline is imbedded. Fortunately there has been no
attack or attempt to gain possession of parts of the pipeline by any military or paramilitary
forces on this pipeline yet to emphasize its interests within its short existence up to now. The
only incident was as mentioned above the interruption of gas transport for a few days due to
the conflict in august 2008. But despite a plan for peace which both Georgia and Russia had
agreed to, the political circumstances are far away from stability and still fragile.
4 Reservoir and production
4.1 Shah Deniz gas field
Shah Deniz gas and condensate field is the largest natural gas field in Azerbaijan. It is
located 70 kilometres south-east of the capital, Baku, covers some 860 square kilometres and
it lies in water depths ranging from 50m in the north-west, to 600m in the south-east. The
exact coordinates of the field are 39º 41´N, 50º 45´E. [7]
Substantial gas and condensate resources were proven in Shah Deniz during 1999.
Two years later, a gas sales agreement was concluded between Azerbaijan and Turkey, that
permited to develop the South Caucasus Pipeline from the first country to the second through
Georgia. Thus, this agreement permits Turks to import 6,6 billion standard cubic metres of
Azerbaijani gas per year, volume which will be covered by the first stage (Shah Deniz Stage 1
Gas Export Project) development of Shah Deniz. Another agreement give rights to Georgia to
take the 5% of the flow of the gas in concept of tariff and 0,5 cubic metters more each year at
a discounted price. Also some of the field gas in locally sold in Azarbaijan.
With a vertical relief of over 1.5km, the mapped structure encloses an area of more
than 300km². The main reservoir rocks within the structure are expected to be at a total depth
19
of 5km to 6.5km and they have been folded into a relatively simple dip-closed anticline
structure.
Reserves of the field are: 1,5 billion barrels (240,000,000 m3) to 3 billion barrels
(480,000,000 m3) of oil, 22,1 trillion cubic feet of gas (more that 600 billion cubic meters)
and 750 million barrels of condensate. Gas and condensate from the field is piped to the
Sangachal onshore terminal, 45 kilometer south-west of Baku, through three subsea pipelines
of 90 kilometer each (660 mm. diameter pipeline for gas, 305 mm. pipeline for condensate
and 102 mm. monoethylene glycol pipeline). All the gas transported through the South
Caucaus Pipeline comes from this field, from Sangachal via the Georgian capital of Tbilisi to
the Turkish border.
The field started to produce gas at the end of Decemper 2006 and in July 2007 the
Shah Deniz gas plant at Sangachal Terminal was fully operational and all buyers of Shah
Deniz gas are were taking gas. In 2007, the field produced a total of about 110 billion cubic
feet of gas and 0.8 million tons of condensate. In 2008, Shah Deniz is forecast to produce
about 271 billion cubic feet of gas and 1.9m tons of condensate.
The Shah Deniz Field is operated by BP, which has a share of 25.5%. Other partners
are Statoil Azerbaijan (25.5%), SOCAR Azerbaijan (10%), Elf Petroleum Azerbaijan (10%),
LukAgip N.V. (10%), Oil Industries Engineering & Construction (10%), Turkish Petroleum
Overseas Company Limited (9%).
4.2 Production and development
The construction and developmet of the field involved a pre-drilling phase consisting
on the placement of 15 slot, 42 tonne seabed guided template and the instalation of 42 preconductor well casings through the template of 1067 mm. diameter each one, 27m into the
seabed and at 103 m. water depth. They focused on two structures, the Fasila Suite and the
Balakhany VIII interval, which form the basis of the field’s first stage of development.
The pre-drilling program included tree production wells. The first well on Shah Deniz
was drilled in a total depth of 6,316 meters, in water depth of 132 meters. It encountered gas
condensate in three separate horizons, with a total net pay zone of 220 meters and had a flow
rate of 1.4 million cubic meters of gas and 3,000 barrels of condensates per day during
production tests. The second pre-drilling development well started in September 2003. The
well waws located on the northeast flank of the field at approximately 101 meters of water
20
depth.The pre-drilling program employed at Shah Deniz allowed for an earlier recovery of the
resources even before the installation of the platform.
Shah Deniz is being developed with a TGP500 platform whose topside was built in
sections in Singapore´s Keppel Fels yard in July of 2004 and transported to Baku by canal.
The platform legs were constructed in Baku, while the drilling equipment and derrick was
built at Nymo facility in Grimstad, Norway and were shipped to the Caspian via the Baltic
and the Russian canal system. The assembly of the platform took place at a yard in Baku. It
was installed on the field in May 2006. The topside is divided into four main sections with
additional process modules containing separators and manifolds pipework extending from the
hull. The rig can accommodate 110 people and includes a helipad. The platform is fitted over
a 16- well slot and is integrated with drilling and processing equipment. The design of the
TPG500 platform is such that it can be removed from site once drilling and production work
are completed.
In November 2007, BP announced it had discovered a new, high-pressure reservoir in
a deeper structure beneath the nortern flank. The fourth production well (SDX-4) was drilled
to a Caspian-record depth of 7,300m in the southwestern part of Shah Deniz and tests showed
a flow of 35 m standard cubic feet per day, with likely reserves not so larger than those in
stage one. This will form the basis of the second stage of development once appraisal over the
next few years has delineated this new structure. Also, in December 2007, BP put in operation
thefifth drilled well (SDA-5) which is designed to reach a depth of 7,180m. BP plans to begin
drilling one more well in 2008, which is scheduled to finish in early 2009. This stage 2 project
will include also an offshore gas platform and a gas plant at Sangachal Terminal with an
estimated cost of at least 10 billion dollars.
5 Processing
5.1 Sangachal terminal
21
The Sangachal Terminal is an industrial complex consisting of a natural gas
processing plant and oil production plant, located on the coast of the Caspian Sea at
45 kilometres south-west of Baku, capital city of Azerbaijan. The terminal is operated by a BP
led consortium and is one of the largest oil and gas facilities in the world. Other partners are
from AIOC, Baku-Tbilisi-Ceyhan pipeline, Shah Deniz and South Caucasus Pipeline projects.
The terminal receives oil from the Azeri-Chirag-Guneshli field and natural gas from the Shah
Deniz gas field. The oil is exported via the Baku-Tbilisi-Ceyhan pipeline to Turkey's
Mediterranean coast and via the Baku-Supsa Pipeline and the Baku-Novorossiysk Pipeline to
the Black Sea coast. Natural gas is transported through the South Caucaus Pipeline via
Georgia into the turkish border. Construction of the terminal began in 1996, which foreseen
construction of pipelines to Supsa and Novorosyisk. Oil was first exported in October 1997.
Facilities at the oil production plant include separators, coalescers, crude oil storage tanks,
Export Pumps, gas turbine power generators and a central control room. The three crude oil
storage tanks have a capacity of 880000 barrels each.
The terminal was expanded to include the ACG Phase 1, Phase 2 y Phase 3 and the Shah
Deniz gas plant (Shah Deniz Stage 1 Gas Export Project). The enlargement was conducted in
March 2006 and included a new onshore hydrocarbon reception system and processing
facilities for both ACG and Shah Deniz, sub-sea pipelines for the transportation of oil and gas
from the offshore platforms in the respective fields to the Sangachal Terminal and the
extension of the existing Sangachal Terminal to increase its processing and storage capacity to
accommodate the increased production of oil and gas from the ACG field, and new
production of gas from the Shah Deniz field.
5.2 Natural gas processing
5.2.1 Process steps
Natural gas as it comes out of the well can’t be used without further treatment. This
gas contains liquid oil, if it is a combined oil and gas field, as well as liquid water. But there
are also other gaseous components which have to be removed. Mainly acid gases like H2S and
CO2, nitrogen and water vapour. There also traces of mercury which has to be extracted from
the gas stream because of its toxic properties. The sketch below shows the block diagram of
one possible process chain to reach these aims:
22
raw gas
Separation
of gas and
liquid
liquid
water
acid gas
removal
dehydration
acid
gases
water
nitrogen
sales
natural gas
gas
separation
nitrogen
removal
mercury
mercury
removal
ethane
fractionating
propane
LPG
butane
Figure 8 Flow diagram of natural gas processing [4]
The first step is the separation of gaseous and liquid phases. Gases are removed
afterwards. The last step is to remove other valuable components, hydrocarbons like ethane,
propane or butane, the liquefied petroleum gases. The reason for removing those combustible
components is that one has to prevent the formation of liquids during the transport in
pipelines. Because of their lower dew point these higher hydrocarbons are in danger to
condense during the transport. Another reason is that one has to supply a certain gas
composition according the demands of the consumer of the gas.
5.2.2 Water removal
When the gas comes out of the well water is present in two different states, it can
either exist as a gas phase or in condensed form as liquid water. It’s very important to remove
liquid water from the natural gas because water could cause corrosion in pipelines and other
devices necessary for the gas production. But nor only the liquid part is a problem, also water
vapour could condense during the transport in the pipelines because of a decreasing
temperature.
A second problem connected with the presence of water in natural gas is the formation
of gas hydrates. Depending on boundary conditions Methane molecules can be placed in a
crystal grid of surrounding water molecules and create a solid ice-like substance. An
23
accumulation of such solid materials enlarge the flow resistance in the pipelines significant up
to a total blockade of the profile. An increasing flow resistance leads to increasing pressure
drop which has to be compensated by higher compression work what leads to higher
operations costs. It is rather facile to remove liquid water from the gas stream in comparison
to the removal of water vapour by using a separation vessel. In such a vessel are also other
liquid components like hydrocarbons separated. The removal of water vapour demands a
more complex treatment of the gas. There are several methods available to solve this problem.
5.2.2.1 Cooling
A first possibility is to cool the whole gas stream below the dew temperature of water
at the given pressure so that all the water condenses and can be separated. However this
process represents an insufficient way to get rid of the majority of the water vapour due to the
large refrigeration plants needed to reach the demanded temperatures. Another disadvantage
is the high energy consumption of such a process.
5.2.2.2 Absorption
The main absorption process related to the water removal represents the absorption
into ethylene glycol. A schematic flow diagram below shows the main process steps:
dry
gas
operation
water
vapour
regeneration
1
2
6
4
water
vapour
3
wet
gas
5
external
heat
Figure 9 Flow diagram of water removal [4]
The liquid glycol is exposed to gas stream in a counter current column (1) where water
is absorbed to glycol. At the bottom of the column a water rich glycol solution is extracted
24
and heated up through the top of the regenerator (2). After that this solution is throttled down
and led into a flash vessel (3). The absorbed water is partly evaporated in this step and can be
extracted as gaseous water, this is called stripping. The remaining liquid is treated with
external heat (5) in the regenerator column (4) where the rest of the attached water evaporates.
The now water lean glycol solution can now be led back to operating column.The whole
process is limited in its capacity by the rest water content of the glycol at the inlet of the
absorption column. This water concentration itself is a function of temperature reached in the
stripping process. The temperature here is limited by the boiling point of the glycol. If this
point is reached no more water can be extracted out of the glycol than the equilibrium at this
given temperature allows. For a further water removal other efforts are requested like drying
the glycol with hot gas or vacuum distillation what would make the whole process
uneconomic.
5.2.2.3 Adsorption
Because of the disadvantages discussed in point b) other techniques are preferred to
remove water. One important process is the adsorption of water on solid materials like silica
gel or molecular sieves. These materials provide a large internal surface where water
molecules can adsorb on. This adsorption takes place as physical adsorption what means that
there is no chemical reaction occurring between the water molecules and the substance where
it is stuck to. This process is reversible so that one can use the silica gel or molecular sieves
after stripping off the water again by running the plant in a circle process.
In order to create a continuous process one has to provide at least two vessels
containing adsorption material. While one vessel is fed with the wet natural gas to be dried in
the other the regeneration process takes place. Therefore the pressure in this vessel reduced to
facilitate the evaporation of water. The energy necessary for the water evaporation is provided
by a hot and dry gas stream flowing through the vessel. This regenaration gas stream carries
the water vapour out of the vessel and has to be cooled afterwards to condensate the water.
As soon as the maximum water capacity of such an adsorption package is reached the
flow of the wet natural gas stream is switched to the regeneration vessel which becomes then
the operating vessel. The former operating vessel can be regenerated. Because of the different
pressures in those two vessels (higher pressure in the adsorption vessel, lower pressure in the
regeneration vessel) this process is called pressure swing adsorption (PSA).
25
5.2.3 Acid gases
Natural gas contains acid gases like CO2 and H2S for example when it comes out of
the well. To protect the following devices from corrosion those components have to be
extracted from the gas stream. The most common process to serve this purpose is a treating of
the raw gas with amines. Monoethanolamine (MEA), Diethanolamine (DEA) and
Methyldiethanolamine (MDEA) are used therefore in most cases. These processes work
according to the principle of absorption where CO2 and H2S respectively. The raw gas is lead
into a packed column where it is exposed to the amine solution. The amine solution is
enriched during its residence in the column and leaves as so called rich solution. This rich
solution has to be regenerated in a distillation column where the acid gases as light
components can be sucked off at the top of the column whereas the heavy component the now
lean amine solution is pumped back to feed the fist packed column.
Cleaning
Regeneration
Condenser
acid
gases
sweet gas
lean amine solution
sour gas
enriched amine
solution
Heater
Figure 10 Flow scheme of a typical amine process [4]
5.2.4 Nitrogen
Another component which has to be separated from the gas stream is nitrogen. The
reason for that is that nitrogen forms NOx during combustion processes what has to be
avoided in terms of environmental protection. In addition nitrogen would have to be heated up
26
during the combustion which reduces the efficiency of the whole process. By reducing the
amount of nitrogen in the natural gas one can define the Wobbe-Index.
One possible way to solve this problem is to apply a cryogenic process, where the gas
stream is treated in a low temperature double distillation column. For application where the
mole fraction is less than 25 % one need a second column as pre-treatment.
The crude gas is cooled in the first heat exchanger (1) and partially condensed in (2).
The nitrogen rich gas phase of (2) is lead to the lower part of the double distillation column
which is run on high pressure and enters it as a feed stream in the sump of this column. The
liquid phase is pre-treated in a distillation column (11) where the mixture is separated to a
nitrogen lean fraction which is pure enough to be used as product gas. The heating of the
sump is given by heat exchanger (1). The flow diagram the double distillation column is
shown as two separated column connected through a heat exchanger (7). In reality these two
columns are designed as one unit where the top of the high pressure column heats the sump of
the low pressure column. In this column the gas mixture is separated to a nitrogen lean sump
product and a nitrogen rich top product. Both streams are pumped afterwards into the low
pressure column, where the top product is condensed in heat exchanger (4) and presents the
reflux, the sump product is cooled in the heat exchanger (3) and presents the feed for the low
pressure column. In this low pressure column the stream is finally separated in top fraction
consisting of nitrogen in a very high purity which is heated up in the heat exchangers (4), (3)
and (1). The sump product consisting of a nitrogen lean liquid methane fraction is compressed
in (8) and afterwards evaporated in (3) and heated up in (1). This product gas can finally be
compressed in (9) and (10) to a certain desired pressure.
27
N2
9
10
product
gas
4
1
3
crude
gas
5
2
low
pressure
11
8
7
6
high
pressure
Figure 11 Flow scheme of a nitrogen removal [4]
5.2.5 Mercury
There are also traces of mercury in raw natural gas which have to be removed from the
gas stream. Mercury can form amalgam with aluminium which would cause huge problems
concerning the mechanical stability in heat exchangers. One common way the remove
mercury is to use activated carbon where mercury is adsorbed to the surface.
5.2.6 Natural Gas Liquids (NGL)
Natural gas contains also a certain amount of higher hydrocarbons like ethane,
propane or butane which have to be removed from the gas stream because these hydrocarbons
can more easily be condensed because of their lower dew point than methane. A formation of
liquids during the transport in the pipeline has to be prevented though. The removal of those
components is realized in stepwise fractionating. At first ethane is removed, after that propane
and finally butane is removed in similar devices. Below the device removing butane shall be
figured, all other devices are similar arranged. The difference is that ethane is removed at a
28
higher pressure than butane because of its higher boiling point and a lower pressure in
comparison to ethane. One possibility to reach this aim is shown below. The crude gas is
cooled down a partially condensed in heat exchanger (1), the formed liquid is separated (2),
expanded, heated up in heat exchanger (1) and fed into a distillation column (4). The gas
fraction of (2) is divided into two streams. The larger one is expanded in a turbine (3) to the
pressure of the following distillation column where the now partly condensed stream is fed
afterwards. The other part is cooled in second heat exchanger (7), expanded and fed as reflux
into the top of the column. At the sump of the column butane and other higher hydrocarbons
removed. The top product mainly consisting of methane heated up in heat exchanger (7) and
(1) and finally compressed to the desired pressure (5) and (6).
6
product
gas
7
5
P-25
4
3
1
2
Crude gas
higher
hydrocarbons
Figure 12 Flow diagram of NGL removal [4]
6 Transport
6.1 Gas pipelines
Due to the large distance between the natural resources and the markets of natural gas
it is necessary to transport the gas in pipelines. As easy as it sounds it is not. The
transportation requires a whole extensive network of pipelines and equipment to do that in a
safe, efficient and economic way.
29
There are three major systems along the transportation route:

The gathering system: transport of gas from the well to the processing plant

The interstate/intrastate pipeline: transport of natural gas over long distances,
at which interstate pipes carry the gas across state boundaries and intrastate
pipelines transporting it within a particular state

The distribution system
This section will cover interstate pipelines because it is the type which applies at the
South Caucasus Pipeline.
To carry the gas from one point to another a driving force is needed. This force is the
pressure which could be anywhere between 15 and 100 bars. As mentioned earlier the whole
transportation system consists of a number of different components ensuring the efficiency
and reliability that is needed in order to run this system.
6.2 Pipes
Pipes can measure a diameter between 6 to 48 inches and are built of strong carbon
steel materials to meet the standards set by the American Petroleum Institute (API). On the
outside of the pipeline there is a layer of bitumen under a casing of concrete to prevent
corrosion and secure the pipe from mechanical attacks. The inner side of the pipe is often
coated. This avoids corrosion and rusting caused by moisture or corrosive gases like H2S and
CO2. Furthermore it decreases the friction factor of the pipe. This friction factor has one of the
main influences on the pressure drop of the pipe. The pressure drop is the most important
parameter to look at by designing a pipeline and defining the pressure levels generated by
compressors.
The work to drive these compressors is a main indicator for the efficiency of the
transportation of the gas. Following equations describe the pressure drop in a pipe:
Where g stands for the gravity pressure, a for the acceleration pressure and f for
friction pressure. The pressures are defined in the following way:
30
Thereby is ΔL the length, f the friction coefficient of the pipe, u the velocity, ρ the
density of the gas, g the gravitation constant and α the gradient of the elevation. The friction
coefficient depends on the Reynolds number of the fluid, that is to say the degree of
turbulence of the fluid flow and the relative roughness of the wall (absolute roughness divided
by the diameter of the pipe). The following chart shows the relation:
Figure 13 Moody friction factor chart (Moody 1944) [6]
6. 3 Compressor Stations
As mentioned before compressors are needed to ensure that the gas remains pressurized on
the way through the pipeline. Compressor stations, driven by a turbine, a electrical motor or
an engine are placed at several intervals along the pipe depending on the pressure losses.
Turbines or Engines are often driven by the natural gas itself.
Compressor stations often contain some type of liquid separator. It is not uncommon
after processing that certain amounts of water are still in the gas, which could condense out of
the gas during the movement through the pipe. Usually, the separators consist of scrubbers
and filters capturing these liquids or other undesirable particles from the gas. So it is ensured
that the gas is as pure as possible.
31
6.4 Metering Stations
Beside the compressor stations, metering stations are also placed periodically along
the pipeline. These stations allow the operator of the pipeline to monitor and manage the flow
through the pipeline. They are provided with equipment, measuring and tracking the flow
along the pipe. Measured parameters are for instance: the temperature, the flow rate, the
pressure, the delivered energy (mass x calorific value of the gas) and mass % of each
component (CO2, N2, C1, C3, iC4, nC4, iC5, nC5 and C6+). These parameters show the
quality of the gas and indicate if the required specifications are met.
6.5 Valves
Along the pipeline there is a great number of valves often placed at constant distances.
They allow the operator to stop the gas flow so that he has free access on the pipe to do
maintenance or replacement of pipeline sections. Valves are also to be considered as a
security getaway due to damages or disaster along the pipe. But in the ordinary working
process they are open and allow the gas to flow freely.
6.6 Control Stations
The data which is produced in metering and compressor stations needs to be handled
and interpreted in order manage the natural gas flow into the pipeline. Collecting, converting,
and assimilating of this data is done in control stations. They contain advanced control
systems to monitor the parameters like the gas flow, the pressure, the temperature and to
ensure that the customers receive their ordered amount of gas in the right quality on a reliable
and safety way.
Systems used in control stations are Supervisory Control and Data
Acquisition systems (SCADA). This system is working in real-time, meaning that the
information which is taken from the measurement points is immediately evaluated and
directly available for the engineers in the control stations. Thus quick reactions to equipment
malfunctions, leaks and other unusual activities along the pipeline can follow in order to avoid
serious accidents to the pipeline and the environment.
6.7 Pipeline Inspection
For the inspection of the pipeline by the operator are sophisticated pieces of equipment
used known as pigs. These are robotic devices which are put in the pipeline to evaluate the
32
interior. They can test the pipe thickness, roundness, detect leaks and other defects. This
inspection is called as ‘pigging’ the pipeline.
7 Simulation
7.1 Given data
We have used HYSYS for the simulation of the Caucasian pipeline to find out some
interesting data like the amount of energy used in each part or the pressure drop inside each
pressure station.
As a start we have used the diagram shown in Figure 1.
In the diagram we can see that the pipeline goes trough different countries with
different altitude in each pressure station. Our pipeline is SCP so we are not considering the
BTC pipeline after the SCP ends.
Here is some data we have used for the start of the simulation:
 The inner diameter of the pipeline is 42”, including the coating. Here we have made an
assumption of the outer diameter of 46”, including coating.
 The total length of the pipeline is 690 km, which 445 km of it is built in Azerbaijan
and 245 km in Georgia.
 The entry point pressure is 90 bars.
 The capacity of the pipeline is 22.08 mmscmd (MSm3/d).
The summary of the flow rates:
Design Flow Rate
Description
Daily
(mmscfd)
Annual
(mmscmd)
(bcma)
33
Delivery to Turkey
638.2
18
6,3
Georgia
36.9
3
0,81
BTC Fuel Gas
29.7
0,8
0,3
Total Pipeline Flow
779.6
22.08
7.41
Table 1 Summary of flow rates [1]
In each off-take gas there is a pressure station with metering station and pressure
reduction. Also the off-take points have specific requirements for the flow conditions, so
we had to install a valve and a heater to fulfill the requirements (table 4).
The composition of the flow we used:
Components
Summer (mol %)
Winter (mol %)
Nitrogen
0.19
0.19
CO2
0.21
0.21
Methane
94.89
94.90
Ethane
3.05
3.05
Propane
1.04
1.03
i-Butane
0.19
0.19
n-Butane
0.26
0.26
i-Pentane
0.07
0.07
n-Pentane
0.06
0.06
Hexane
0.03
0.03
Heptane
0.01
0.01
100.00
100.00
Total
Table 2 Gas Composition [1]
As we can see the composition is without H2O and other components like mercury or
H2S that could be inside the main composition, so we assumed those were taken out before
going into the pipeline.
34
The off-take fuel stations are specified in the following diagram:
Kilometer
point (KP)
Description
Flowrate (scmh) see note
Min
Max
243
Pump Station PS-A2
260
11 000
446
Pump Station PS-G1
260
14 000
529
Pump Station PS-G2
260
13 000
Table 3 Gas pump stations [1]
The requirements of each off-take fuel stations are specified in the following diagram:
Description
Sangachal
BTC
Georgian
Offtake PRMS
Turkish
Delivery Point
All Points
Maximum Supply Pressure (barg)
90
N/A
N/A
N/A
Minimum Supply Pressure (barg)
76
N/A
N/A
N/A
Maximum Delivery Pressure (barg)
-
34.5
20
75
Minimum Delivery Pressure (barg)
-
26
10
56
Maximum Supply/Delivery
Temperature (oC)
64.0
70
64
45 static, 25
flowing
Minimum Supply/Delivery
Temperature (oC)
5.0
13
0.0
5.0
Table 4 Off-take fuel stations [1]
35
7.2 Approach for HYSYS Simulation
Figure 14 HYSYS Flow Sheet
36
Specifications of the HYSYS simulation:
 Items been used:
o Pipe segment
o Compressors
o Heaters
o Tees
o Valves
Pipe segments:
 Length
 Inner diameter
 Outer diameter, made an assumption of 46”.
 Elevation change, which we could see it in the following diagram [1]
Figure 15 Elevation profile of SCP [5]
 Beggs and Brill pipeline correlation
 Material: Mild Steel
 Heat Transfer specified by Overall HTC, which includes specifying ambient
temperature and Overall HTC. The Ambient temperature is an assumption
based on the average temperature over one area. We mostly assumed it was
around minimum 5 ºC and maximum 20°C. The Overall HTC we used is taken
from lecture notes from Jon Steinar Gudmundson
[8]
, which specifies U
(W/m2*K) between 1 and 2 for isolated materials, so we picked 1.5 W/m2*K.
Compressors:
 We specified the pressure in the flow going in, and the flow going out, with an
adiabatic efficiency of 75%.
37
Heaters:
 We specified the temperature of the flow going out, depending on the requirements of
each off-take fuel point.
Splitter:
 We aggregated 3 streams supplying the BTC pipeline to one stream at KP 243.
Valves:
 We specified the pressure of the flow going out.
7.3 Results
We found out some data from the HYSYS simulation, which we listed in one table:
Pipe segment 1
Pipe segment 2
Pipe segment 3
Pipe segment 4
Sangachal
KP243 in
KP243 out
KP446 in
KP446 out
KP539 in
KP529 out
To turkey
Pressure (kPa)
9000
8308
9000
8239
9000
7836
9000
8026
Temperature (ºC)
5
3.65
10.23
3.8
10.1
0.45
11.85
(-)0.82
Altitude (m)
0
100
100
400
400
1600
1600
2300
Lenght (km)
Compression
power needed
(kW)
243
203
83
161
1157
1248
964.2
3525
Table 5 data [5]
Pressure
KPa
Sangachal
KP243
KP446
KP539
To Turkey
Pressure
Stations
Figure 16 Pressure Drop along SCP [5]
38
Figure 17 Compression power required along SCP [5]
Power for compression (kW)
Power for heating (kW)
compressor 1 compressor 2 compressor 3
2066
2290
3550
heater 1
heater 2
heater 3
15,47
47,81
5957
It has to be notice that the last heater uses a huge amount of energy because the flow
rate is much bigger than the others.
As seen above the pressure drop in the pipeline and therefore the energy loss raises
with a increasing elevation difference and increasing flow distance as explained in the
theoretical part. The roughness of the internal surface of the pipeline has a decisive influence
on the pressure drop. If one uses a coated pipeline the pressure drop declines because of the
decreasing roughness.
39
8 Conclusion
This report showed the big importance of the South Caucasus Pipeline for the world’s
natural gas markets, especially the one in Europe. The SCP is with 690 km length and 42” in
diameter one of the longest pipelines in the world supplying the gas from Azerbaijan to
Turkey across Georgia. The planning of more pipelines, like the Nabucco pipeline connecting
Europe and the South Caucasus, shows that the area around the Caucasus will also be very
important in the future. Furthermore, StatoilHydro one of the main owners of the pipeline
announced to increase the capacity the next years even more.
Reasons for that considerable importance of the SCP are not only because of the big
resource of gas in the Shah Deniz gas field but also because of the political independence
from Russia concerning the gas supply to Europe. But, the increasing crises in the Caucasus
area are not conductive to the gas transport in that region. More and more, local instabilities
and political conflicts affect or even disturb the transport of gas through this area. As we have
seen the shut down of the pipeline in August 2008 due to the conflict between Russia and
Georgia causes uncertainness in reference to the gas supply for the European market which
means no hundred per cent independence from other gas supplying countries.
Nevertheless, the technical aspects of the pipeline are not to be sneezed at. As
mentioned the transport of gas over such a large pipeline distance requires a lot of
compressing energy. Not only because of the large length but also because of the elevation of
the pipeline about nearly 2000 m it is a technical challenge. Since the gas in the pipe is split
up to supply Georgia and the Baku-Tiflis-Ceyhan-Pipeline it is needed in different conditions.
One of these conditions is a low pressure at the receiving terminal. To reach that the gas has
to be throttled down and after that heated up because of the temperature decrease in the valve.
This requires additional energy for running the pipe.
The amounts of energy calculated in the HYSIS simulation correspond not in every way to
the real amounts of the pipeline due to many of assumptions. But the simulation still demonstrates a
good model for the first time looking at the pipeline and evaluating the pipe due to a global
comparison of gas pipelines.
References
[1]
Information provided by Statoil Hydro on request
40
[2]
SCP and BTC:
http://de.wikipedia.org/w/index.php?title=Bild:Baku_pipelines.svg&filetimestamp=20080810
195610
[3]
Political map: http://ww1.huntingdon.edu/jlewis/syl/IRcomp/MapsCaucasus.htm
[4]
Self made according to reference books listed below
[5]
Results obtained from HYSYS simulation
Energy Profile of Turkey:
https://www.eoearth.org/article/Energy_profile_of_Turkey#South_Caucasus_Pipeline
BP in Georgia: South Caucasus Pipeline:
http://www.bpgeorgia.ge/go/doc/1339/150568/
BP Caspian:
http://www.bp.com/sectiongenericarticle.do?categoryId=9006670&contentId=7015095
[7]
Shah Deniz field :
http://www.rigzone.com/data/projects/project_detail.asp?project_id=89
Shangasal Terminal:
http://www.offshore-technology.com/projects/shah_deniz/
Environmental impact assessment of the project:
http://www.ebrd.com/projects/psd/psd2005/35606.htm
Natural Gas pipelines:
http://www.naturalgas.org/naturalgas/transport.asp
SPIEGEL online: The Chronicle of a Caucasian Tragedy:
http://www.spiegel.de/international/world/0,1518,574812,00.html
Wikipedia English site: Nagorno Karabakh War:
http://en.wikipedia.org/wiki/Nagorno-Karabakh_War
Einführung in den Kurdenkonflikt und Politik der PKK;
http://www.medienheft.ch/kurdenkonflikt/kapitel1.htm
Historical Institute of RWTH Aachen: Der Konflikt in Tschetschenien:
http://www.histinst.rwth-aachen.de/default.asp?documentId=84
Handelsblatt, 26.December 2007:
http://www.handelsblatt.com/politik/international/nabucco-pipeline-steckt-inschwierigkeiten;1370287;2
41
Eurasisches Magazin, edition 10-03:
http://www.eurasischesmagazin.de/artikel/?artikelID=101103
Zeit online, 3.January 2008:
http://www.zeit.de/2008/02/PS-Nabucco?page=all
Political map of Caucasus:
http://ww1.huntingdon.edu/jlewis/syl/IRcomp/MapsCaucasus.htm
Books:
[6]
NATURAL GAS ENGINEERING HANDBOOK. Dr. Boyun Guo and Dr. Ati Ghalambor.
University of Luisiana at Lafayette. 2005
http://www.knovel.com/web/portal/basic_search/display?_EXT_KNOVEL_DISPLAY_booki
d=1295
INDUSTRIAL GAS PROCESSING, Heinz Wolfgang Häring, WILEY-VCH 2008
GAS PROCESSING: ENVIRONMENTAL ASPECTS AND METHODS, James G. Speight,
Butherworth Heinemann 1993
NATURAL GAS PROCESSING PRINCIPLES AND TECHNOLOGIES, Dr. A.H Younger,
P. Eng, University of Calgary
Lecture notes (Course TPG 4140, Natural Gas at NTNU Trondheim, autumn 2008 and
2007)
[8]
Pressure Drop, Temperature and Hydrate in Pipelines by Jon Steinar Gudmundsson,
NTNU, September 23, 2008
http://www.ipt.ntnu.no/~jsg/undervisning/naturgass/lysark/LysarkGudmundssonPressureTem
peratureHydrate2008.pdf
TRYKKTAP, TEMPERATUR OG HYDRAT I RØRLEDNINGER, Jon Steinar
Gudmundsson, NTNU, September 11, 2007
42
(http://www.ipt.ntnu.no/~jsg/undervisning/naturgass/lysark/LysarkGudmundssonTrykktapTe
mperaturHydrat2007.pdf)
Natural Gas Metering by Dag H. Flølo, Statoil Hydro ASA, October 7, 2008
http://www.ipt.ntnu.no/~jsg/undervisning/naturgass/lysark/LysarkFloeloMetering2008.pdf
43