Burckhardt Compression has announced that it is part of the ongoing shipment of US shale gas to the INEOS Grangemouth petrochemical site in Scotland, UK.

A set of low-temperature boil-off gas compressors has been installed in each of the multi-gas carriers that make up the fleet of specially designed ‘dragon-class’ vessels at the onshore storage tank in Grangemouth. In addition, Buckhardt Compression labyrinth piston compressors are installed at the polypropylene and polyethylene production plants in Grangemouth.

The petrochemical site, run by chemical giant INEOS, is home to one of the largest cryogenic ethane gas storage tanks in Europe. Burckhardt delivered the Laby® labyrinth piston compressors used to manage boil-off gas in this tank.

Dragon-class vessel at the onshore storage tank in Grangemouth

Dragon-class vessel at the onshore storage tank in Grangemouth

The INEOS facility converts ethane into ethylene, which is used in the production of a range of plastic products, solvents and anti-freezes. The company has stated that the amount of ethane extracted from the North Sea, its long-time source of feedstock, has declined at such a rate that it is unable to operate its ethylene manufacturing plant at design rates. The company therefore sought alternative sources of feedstock in the form of US Shale Gas ethane and signed an agreement with Danish company, Evergas, to build a trans- Atlantic ‘virtual pipeline’ of eight multi-gas vessels, ensuring a steady supply of raw material for the next 15 years.

Each of these ‘Dragon-class’ ships, built by the Chinese group Sinopacific, is able to carry 27,500 cubic meters of ethane gas and have been designed to transport LPG and LNG in addition to ethane. The ships are powered by two Wärtsilä 6L50DF dual-fuel engines, which can be run on ethane, LNG or conventional diesel.

In order to comply with specifications, the main engines have undergone several modifications, including a lower compression ratio. The boil-off gas compression system is designed and delivered by Wärtsilä Gas Solutions, including the compressors built by Burckhardt Compression. The system has been specifically designed to meet all requirements, resulting in an extremely reliable final product with an improved environmental performance.

Burckhardt’s labyrinth piston compression solutions are widely used in fuel gas injection and re-liquefaction systems in marine applications, terminals and FSRUs. Laby® compressors are the first choice in a variety of different applications due to their oil-free design and contactless labyrinth sealing technology, which result in reduced wear on the components and consequently an increased mean time between overhauls. Its design enables flexible shut-downs and start-ups without pre-cooling, and is completely gas-tight. Along with its compressor solutions, Burckhardt also offers a full range of services and components through its global organisation and local service centres.