A riser system for transporting a slurry from a position adjacent to the seabed to a position adjacent to the sea surface

摘要

A riser system for transporting slurry from the seabed to the sea surface. The riser system comprises a first and second riser a slurry pump system (17) to transport slurry up one of the risers and a waste water pump system (107) to return waste water down one of the risers. The slurry pump system and the waste water pump system are selectively connectable to each of the risers to allow each riser to be either a slurry riser (1) or a waste water riser (2). With this arrangement if a slurry riser develops a leak partway along its length the waste water riser can be converted into a slurry riser such that operation can continue.