Atlas Copco Compressors has delivered a large custom-designed main air compressor package to be installed on an offshore platform in the Shah Deniz oilfield off the coast of Azerbaijan
The package weighs 50 tonnes, is mounted on a single skid and comprises 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 main air compressor package is more than 11 metres long, six metres wide and 3.75 metres high, and was delivered in a reinforced crate along with specially-designed lifting equipment to support offloading and handling at its destination.
The package was designed, built and tested at Atlas Copco’s Systems Hemel Hempstead workshop in the UK, which is commonly used to build compressed air and nitrogen installations that are used in the oil and gas industry.
Once installed, the package will provide instrument air for pneumatic controls and actuation of critical valves and instruments on the offshore platform, said Atlas Copco officials.
Systems Hemel Hempstead manager Paul Frost said, “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.”
The size of the total delivered package was nearly almost 90 tonnes, which was moved from the workshop using a 12 tonne forklift truck onto the back of a special heavy load bearing lorry that travelled via police escort to Immingham docks for shipping to Baku, Azerbaijan. During transit, the package is expected to travel via canal, timed to avoid freezing weather conditions, from the Black Sea into the Caspian Sea for installation on the platform.
Since the offshore platform is exposed, the main air compressor package has been weather-proofed, winterised and built to withstand harsh environmental conditions, including wind speeds of up to 45 metres per second, and ambient air temperatures ranging from -7°C to 40°C at high relative humidity. Designed for continuous 24-hour 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 and operational, two of the main air compressors will be running continuously to provide 100 per cent of the platform’s instrument air requirements.
However, in the event of non-availability of one of the compressors, the third – a 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.
