Port maintenance dredging with pipeline transport versus sailing and offshore disposal: a case study on energy demand and CO? emissions
Type:
Presented during:
CEDA Dredging Days 2026
Authors:
E. Meshkati, R. Engels, J. van der Vorm, T. Vijverberg, A. Talmon, E. Hendriks, K. Vasiliki and X. Naaijen
Abstract
Ports around the world are actively seeking ways to reduce conventional fuel consumption and lower CO? emissions. One area receiving increasing attention is maintenance dredging. The PRISMA III project, initiated by the Port of Rotterdam, set out to compare the energy requirements of two sediment disposal methods: sailing to offshore disposal sites versus transport via pipeline. In both methods, maintenance dredging is performed by a hopper dredger. The comparison therefore focuses solely on the transport of dredged material once the hopper is filled, as conventional hopper dredging in the port area remains essential due to the flexibility these vessels provide compared with any stationary alternatives. For pipeline transport, we carried out model predictions to estimate pressure losses when transporting silty mud and sand slurry under both laminar and turbulent flow conditions. To assess the energy use for sailing and offshore disposal, we analysed averaged operational data from 7 hopper dredgers working for multiple contractors. This included publicly available information on vessel dimensions, typical sailing speeds, dredging cycles, and fuel consumption. Our findings show that for transport distances greater than approximately 2 to 3 km - depending on pipeline diameter and sediment rheology - sailing and offshore disposal generally require less energy than pipeline transport. In addition, pipelines demand considerable maintenance and pose logistical challenges at disposal sites. We also explored a potential adaptation of the pipeline system: installing an electrically driven booster pump directly after the dredging pump. While this hypothetical setup may consume more energy than sailing and offshore disposal, using green electricity could reduce CO? emissions. However, such a system would entail significant initial costs and would not resolve the ongoing maintenance challenges associated with pipelines.