Challenges in Research on Pipeline Transport of Solids Using Modern Dredging Equipments

摘要

In recent years the developments of new dredging equipments and techniques have raised new questions regarding the safety and economy of the pipeline transport of solids during dredging operations. The dredges are becoming larger and so are the pipeline diameters. Furthermore, there is an increasing need to dredge in deeper waters what means that inclined suction pipes must be longer. Thus the problem of the effect of a suction-pipe inclination slurry-flow conditions can no longer be considered unimportant as it was in shallow-water dredging situations. Also, new techniques have made possible transport of slurries of increasingly higher solids concentration. The slurry-flow models used for calculations of energy losses and production in a transport system need to be adapted to these conditions. The shiny-flow models assume a steady flow of solids in a pipeline, In many cases, however,the flow is strongly unsteady and this can lead (e.g. In a long discharge pipeline fed by cutter dredges and equipped by boosters along the long pipeline) to various problems unpredictable by the steady-flow models.The paper describes the problems associated with the pipeline transport of slurries under the conditions described above, It discusses the flow behavior on basis of physical mechanisms goveming the slurry flow and shows results of experimental work in bom the field and the laboratory (Laboratory of Dredging Technology of Delft University of Technology). It closes with recommendations for future experimental and theoretical work in the field of slurry transport during dredging operations.