A dredger is an engineering vessel used for dredging rivers, ports, lakes, and other bodies of water. It primarily cleans or expands waterways by excavating, sucking in, and transporting silt. Its working principle can be divided into the following steps:
Excavation and Suction: Dredgers are typically equipped with excavation tools (such as cutters, buckets, or suction heads), which agitate and break up the silt at the bottom of the water through rotation or reciprocating motion. Subsequently, a powerful pump system sucks the mixture of silt and water (i.e., slurry) into a pipeline.
Slurry Transportation: The sucked-in slurry is transported to the designated location through a pipeline system. The pipeline can be floating or fixed, depending on the operating environment and distance. During transportation, the flow rate and concentration of the slurry need to be controlled within a reasonable range to ensure efficient transportation (typically a flow rate of 3-5 m/s and a concentration of approximately 20-30%).
Separation and Discharge: After the slurry is transported to its destination, it may be necessary to separate the silt from the water. Separation equipment (such as hydrocyclones or sedimentation tanks) separates sediment from water. The sediment can be used for landfill or stockpiling, while the water can be recycled or discharged back into the water body.