Allseas’ offshore construction support vessel Oceanic has kicked off offshore works for the Porthos project (Port of Rotterdam CO2 Transport and Storage). The work consisted of a special unexploded ordnance survey along the 20-kilometre pipeline route.

The “bomb hunt” is one of several important pre-lay activities required before Allseas‘ pipelay vessel Lorelay can install the 16-inch pipeline. The hi-tech imaging and sonar spread – capable of visualising objects up to 4 metres below the seabed – detected no explosives.

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Main offshore contractor

Allseas is the main offshore contractor for Porthos. The company’s work includes installation, burial and commissioning of the 16-inch pipeline connecting the future compressor station, located at the Maasvlakte, with the P18-A platform offshore. The offshore pipeline is provided with a plastic insulation coating to retain the heat in the pipe and a concrete weight coating for stability on the seabed.

Lorelay will commence pipelay late April with a pull-in to the compressor station, before setting off in the direction of the P18-A platform. Oceanic will provide construction support. The vessels can position precisely and safely in the busy waters around Rotterdam, the busiest and largest port in Europe.

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First CCS project of its kind in Europe

Porthos is the first carbon capture and storage (CCS) project of its kind in Europe. The pipeline will transport CO2 captured from industry through the Port of Rotterdam to depleted gas fields in the North Sea. The companies supply their CO2 to a collecting pipeline of over 30 kilometres through the Rotterdam port area.

Porthos is a joint venture of EBN (Energie Beheer Nederland), Gasunie and the Port of Rotterdam. Recognised by the EU as a project of common interest (PCI), the project was made possible by a CEF subsidy from the European Commission.

Picture: Allseas’ offshore construction support vessel Oceanic (by Allseas).

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