INFLUENCE OF AIR INJECTION ON SUCTION POWER AND PRESSURE GRADIENT IN DREDGER SYSTEM

Air injection could be a possible solution to prevent blockage along the transport pipeline which commonly occurs during the operation of dredger system. The present paper seeks to investigate the influence of air injection on the performance of dredger system by injecting variant air concentrations. To achieve this purpose, the experiments were conducted under various operating condition such as: initial pump pressure (0.196, 0.294, 0.490 and 0.706 MPa), sediment grain sizes (2, 5, 10 mm, Mixed and Large), transport sediment concentrations (0.8% to 8.5%) and air concentrations (0, 25, 40, 60 and 100 nl/min). The experiments showed that the risk of pipeline blockage is higher in case of fine sediment compared with coarser sizes. Furthermore, the air injection into the system is more effective for lower initial pump pressure (0.196 and 0.294 MPa). Also, the lowest pressure gradient along the transport pipeline was observed for the specific air concentration ranges from 40 to 60 nl/min and specific sediment concentration ranges from 3.5% to 6%.