Atlas Copco Compressors has completed a delivery of a large, custom designed main air compressor package, weighing approximately 50 t. The package was delivered to Baku, Azerbaijan, for installation on a platform located 90 km offshore in the Shah Deniz oilfield in the South Caspian Sea.
Mounted on a single skid and comprised of three ZR500 water cooled screw compressors, a closed circuit water cooling system, three heatless dryers and separate ZT110 black start screw compressor for emergencies, the package was purpose designed, built and fully tested at Systems Hemel Hempstead, one of Atlas Copco’s six global competence workshops. These six centres are where the company creates and assembles bespoke compressed air and nitrogen generation installations, primarily for the oil and gas industry.
About Atlas Copco’s main air compressor package
The physical size of the main air compressor package – 11 m long, 6 m wide and 3.75 m high – meant that it had to be delivered in a reinforced crate, alongside specially designed lifting equipment to support offloading and handling at its destination. The additional equipment brought the total size of the final delivered package to almost 90 t, which was moved from the workshop, using a 12 t fork lift truck, onto the back of a special heavy load bearing lorry which travelled via police escort to Immingham docks for shipping to Baku. During transit, the package travelled via canal – timed to avoid freezing weather conditions – from the Black Sea into the Caspian Sea, for installation on the platform.
Conditions at the Shah Deniz oilfield
Due to the exposed nature of the offshore platform where it is to be installed, the main air compressor package has been weatherproofed, winterised and built to withstand harsh environmental conditions, including high wind speeds of up to 45 m/sec. and ambient air temperatures, ranging from -7°C to +40°C at high relative humidity. Designed for continuous 24 hr operation, the package was tested to withstand inertial accelerations as a result of seismic activity and is also soundproofed to operate with low noise emissions.
Once installed, the main air compressor package will provide instrument air for pneumatic controls and actuation of critical valves and instruments on the offshore platform. Under normal operating conditions, two of the main air compressors will be running continuously to provide 100% of the platform’s instrument air requirements. However, in the event of non-availability of one of the compressors, the third, standby compressor, will start and provide the necessary capacity. In the event of a power failure and loss of the main air compressor package, the black start air compressor, which is supplied by the platform’s emergency power generator, will start and provide the minimum compressed air needed to safely shutdown the platform operations.
Comment from Atlas Copco Compressors
Paul Frost, Manager of Systems Hemel Hempstead commented: “The completion of this latest package is an excellent example of the technical expertise and cutting edge facilities we are able to deploy at Systems Hemel Hempstead, which has attracted increased demand from the global oil and gas industry in recent years. For this project we had to take several challenging design and environmental considerations into account to ensure we met the customer’s specific requirements both on time and within budget.”
Edited from press release by Cecilia Rehn