The feasibility of installing a suction system, which consists of a pump and pipeline for transporting sediment from the sediment trap to the reallocation site to complement the water injection dredging (WID) method is accessed in this thesis. The combination of a suction system and a water injection dredger is called central suction-WID system. This thesis analyses the sediment return volume, necessary pump power, greenhouse gases production and necessary costs for implementing a central suction-WID system. Three different reallocation sites with different distances for central suction-WID are assessed: Inside of Nieuwe Waterweg, Outside of Nieuwe Waterweg, and Verdiepte Loswal..
Delft3D-Flow numerical model is used for modelling the hydrodynamic and the sediment return volume. The simulation is run for 14 days period in order to simulate spring and neap period. The numerical model result shows that discharging the sediment at the inside of Nieuwe Waterweg leads to the most sediment return, while discharging at the Verdiepte Loswal leads to the least sediment return volume. Increasing the sediment volume or reducing the particle size does not affect the sediment return rate.
The necessary pump power and energy consumption for reallocating the sediment to each location are assessed. The calculation shows that the major contributor to the energy consumption is the friction between the fluid mud and the pipe wall. Reallocating the sediment to the inside of Nieuwe Waterweg consumes the least energy while transporting it to Verdiepte Loswal needs more energy as it is the furthest reallocation site alternative.
Using a WID vessel produces fewer greenhouse gases than hopper dredger as it consumes much less fuel. Costs analysis shows that using a central suction-WID system is more expensive compared to hopper dredger. The costs of using a central suction-WID system increases as the distance between the sediment trap and the reallocation site is higher. However, combining it with another dredging method can be an alternative as it reduces the operational costs.