RISER SYSTEMS

摘要

Riser system for taking up large amounts of cold seawater from large depth to a turret or similar in a vessel than in principle lays in a fixed position on the sea surface by spread anchoring from the turret or by dynamical positioning, which vessel can rotate freely around the turret while the turret in principle is without rotation with respect to the sea surface. The riser system is distinguished by comprising: a single riser having a large flow cross-section, which riser in operation extends from a lower bottom anchored end at large depth from where large amounts of cold seawater are taken into at least one opening and is passed through the riser to an upper end a little below or in the sea surface; a buoyant body arranged in the upper end of the riser, which buoyant body holds the riser in upright position; one or more flexible pipes arranged from the upper end of the riser to the turret, to pass the cold seawater from the riser to the vessel, with fluid communication through or bypassing the buoyant body. Alternatively the riser is suspended in the turret. The invention results in reduced cooling water demand.