Dredging is the removal of minerals and sediment such as sand and gravel - used in the construction industry - from a stretch of water such as a harbour, river or the sea bed and moving it to another location.
Dredging is an alternative to quarrying and the process is carried out by a vessel called a dredger. Dredging is a three-step process: excavation of the material, transportation of the material and its unloading.
Companies building in urban areas in close proximity to harbours or estuaries often favour sourcing aggregate from dredging over quarries. This is due to easier and quicker access to the aggregate plus lower transportation costs.
Over 20% of the UK’s supply of sand and gravel is dredged from the seabed. As land-based quarrying comes under pressure from environmental and planning restrictions, this marine resource is growing in importance in the construction supply industry.
Pumps Fitted on Dredgers
Large-scale marine dredging is achieved by a fleet of purpose-built aggregate dredging ships, operating around the clock in all weathers. At the heart of the dredging process are powerful electric-powered centrifugal pumps, capable of drawing sand and gravel in large volumes from the seabed, which can be up to 60m below the ship.
In addition to these huge pumps, slurry pumps are required to pump the excess water back to the sea. These pumps need to be very reliable and capable of handling abrasive fluids. An ideal application for SlurryPro pumps.
SlurryPro pumps can be found on a number of dredgers in the UK including the Southampton-based vessel ‘Clarissa’ which is owned by Aggregate Industries and on a vessel owned by CEMEX UK Marine - also based in Southampton.
Most notably, the new CEMEX UK Marine dredger ‘CEMEX Go Innovation’ (pictured above) which is being built by the Dutch defence, shipbuilding, and engineering conglomerate Damen Shipyards Group will feature two built-up SlurryPro 6x4 centrifugal slurry pumps. The vessel will be delivered in late 2019. Find out more about SlurryPro here.