Gas And Process Stories. Atlas Copco Gas and Process and Iran s Gas Development Program. CopcoCustomerNews. Volume 1 January 2004

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1 CopcoCustomerNews Atlas Volume 1 January 2004 Gas And Process Stories This is the first edition of a new customer news-sheet from Atlas Copco Gas and Process a division within the Atlas Copco Group. Atlas Copco Gas and Process began in January last year, when the centrifugal compressor business was reorganised to better address the markets that we serve. This gives us the opportunity to rededicate ourselves to putting customer needs first, by manufacturing, selling and servicing high quality, state-of-the-art turbo machinery systems. The first story is about a large project for compressors and Turboexpanders in Iran. Atlas Copco Gas and Process and Iran s Gas Development Program. The core of Iran's natural gas development program is in the South Pars field on the Iranian Coast in the area of Assaluyeh village, approximately 270 km southeast of Bandar Bushehr. Eni Iran is developing the South Pars Project Phases 4 and 5 for NIOC in Iran. Eni holds a 60% stake in this venture and the local state companies, Petropars and Niol, the remaining 40%. The goal is to produce some 50 MMm 3 /d of gas for the market, together with 1.05 MMt/y of LPG, 80,000 b/d of condensate, 1.0 MMt/y of ethane and 400 t/d of sulfur. The output will be used both for domestic consumption and pipeline exports. The project includes: Two well-head platforms A gas treatment plant located Onshore Two sea lines to be laid between wellhead platforms and the Onshore plant to transport the reservoir fluid.

2 Optimised compressor design Atlas Copco GAP has delivered 8 single stage compressors for the dehydration plant. The different operation modes for the dryer system are: Heating mode Cooling mode Equalising of pressure Switching from stand-by to operation These operation modes require an optimised design and control system of compressor, especially for compressor start up under high pressure. Therefore the compressor is equipped with hydrostatic axial-bearings. About the compressors: The order for compressors consisted of twelve single stage machines which are very similar in design: eight dryer regeneration (Methane) and four Ethane regeneration compressors (Ethane) The gas produced during regeneration is fed via the gas furnace, the dryer and an air cooler to the regeneration knock out drum, where water is separated from the gas. From this separator the saturated gas enters the compressor at a pressure of 59 bara. The compressed gas at a pressure of 66 bara is then directed back to the wet gas line. How the Dryer Regeneration works When a Dryer becomes water saturated, it is taken off adsorption mode and is regenerated to remove the residual water. Another Dryer, which has previously completed the regeneration steps, replaces the previous Dryer in the adsorption mode. 10% of dry gas is taken off for regeneration of the dryer. The recovered gas is then compressed in the Dryer Regeneration Compressors and recycled back to the Wet Gas/Treated Gas Exchanger along with main feed flow. Control: For process-related reasons, the pressure downstream of compressor suction drum must be kept at a constant level. Thus, suction pressure is a variable of the compressor capacity control system. The set point from the suction controller is changed to a lower value when the maximum motor power is reached (cascade control). As a minimum flow must always be maintained in the compressor, each compressor is equipped with a recycle valve and surge controller. During recycle or bypass operation of the compressor, hot discharge gas is cooled by a gas air cooler.

3 Hydrocarbon business Atlas Copco is one of the pioneers for the use of Active Magnetic Bearings (AMB) in Turboexpanders. The first AMB Turboexpander installation was in 1990 for an air separation plant in Japan. Following this development, our knowledge and knowhow was further extended jointly with Rotoflow, a former Atlas Copco Group manufacturer. Atlas Copco was deeply involved in detailed machine design, rotor dynamics, thermodynamics and general design issues. This was through our common development team. Together with S2M of France, our partner for supply of AMB Systems, we worked intensively to achieve the highest level of operational reliability. The four Type ETB AMB Turboexpanders that we have delivered for the South Pars 4+5 Project, further confirm our capability and know-how to supply expanders with AMB for hydrocarbon applications. Design optimisation has been undertaken with use of state of the art Finite Element Modelling (FEM) and Fluid dynamic tools. Atlas Copco Turboexpanders fitted with Active Magnetic bearings offer the following advantages: Low operating costs - no wear - no lube oil system or oil management required Higher efficiency due to reduced mechanical losses No oil contamination of product possible No avoid speed range of operation Automatic rotor Thrust Balancing function Proven reliable technology Smaller Footprint Reduced Instrumentation Complexity

4 Turboexpanders for the Ethane recovery plant of the South Pars Project Atlas Copco has delivered four identical Turboexpanders type ETB 300 MS for the South Pars Phases 4 & 5 Facilities Project. These machines expand 365,500 Nm 3 /h of natural gas from 60.9 bara to 30.4 bara. They are fitted with active magnetic bearings. Process description: The gas comes from a Dehydration unit in each gas train. The dry gas is then cooled in a Cold Box exchanger. Condensed liquids from the cooled gas stream are removed in a single inlet scrubber prior to entry to the Turboexpander. The gas is warmed before being sent to the re-compressor. The gas expansion duty and re-compression duty are performed inside a single body machine where the compressor is acting as a brake for the Turboexpander.

5 Always seeking the best technical solution Working closely together with customers and suppliers Atlas Copco is the company with the widest and best operating experience with integrally geared centrifugal compressors for high inlet pressure duties, such as the dryer regeneration gas compressors for the South Pars Project in Iran. Due to the high inlet pressure, of up to 59 bara, the compressor has a very high axial thrust that needs to be compensated by a special axial bearing arrangement. Atlas Copco has developed a unique device, which minimises axial thrust during start up, to minimise the required start up torque of the motor driver For this particular project, It was also a customer requirement to optimise as far as possible, the interchangeability of parts in order to minimize the number of required spare parts between the compressors for the different plant applications, including the compressor rotors. To achieve this requirement, the compressor designs were optimised and special impellers and stage internals that can handle the required small volume flows at a low pinion speeds were used, in addition to using standardised common componentry wherever possible. Atlas Copco has a broad spectrum of the latest impeller designs and types available to fulfil this type of customer requirement. Eni commented after delivery, Atlas Copco with both the integrally geared Compressors and Turboexpanders, satisfactorily performance tested these in the workshop and delivered them on time. They maintained an efficient management system and good relationship with both Company and contractor. The South Pars compressor design includes API 617 7th edition API 614 oil system NACE condition 100% wet gas service Lethal gas service High corrosive atmosphere Casings, impeller and shaft sealing designed for -46 C and 82 barg

6 Markets are changing Over the last decade our business has focussed more of its activities on the petrochemical and natural gas markets. Atlas Copco Gas and Process has also benefited from rising oil prices, which has encouraged our customers to squeeze more products from natural gas. Twenty years ago many operators simply burnt unwanted gas extracted from oil in huge flares. Nowadays, people think it s logical to use this gas and one of the processes they are using is the gas-to-liquid (GTL) process, explains Dré Schmitz. In the past, natural gas was only used for power plants, or for industrial and domestic heat. Today more people think seriously about getting more sophisticated products and wider use from natural gas. Atlas Copco Gas and Process supplies machinery for plants which break natural gas into basic components including carbon monoxide and hydrogen to form, for example, Syngas, which is then either put through the GTL process to make products such as waxes and designer fuels or converted to methanol. Dré Schmitz President of Atlas Copco Gas and Process Division In recent years our business has widened its focus from the European market and has increased its activities in Asia. Dré Schmitz says, In the past we had a mostly European market, especially for air separation. In the last three years this has moved to Asia, especially China, where they are revamping steel plants and need huge air separation plants. Whilst the market here was flat, Asia was booming. Today we face a little slowdown in the Asia area but now the European market is waking up and coming back. The markets for Atlas Copco Gas and Process products are constantly changing. However, because each individual machine is built from standardised functional elements, our product range has built-in flexibility. We need to be very flexible to follow the market changes, says Dré Schmitz. But as we engineer every product, we can adapt very fast to the changes. For further information on our products and services, please contact us: Atlas Copco Energas GmbH Gas And Process Am Ziegelofen Köln, Germany Telephone: +49 (0) Telefax: +49 (0) atlascopco.energas@de.atlascopco.com