Estimating Erosion Degradation of Deep-Sea Mining Transportation Pipes Using a Discrete Phase Simulation Approach

Deep-sea mining transportation pipe connects the seabed mining vehicle and the buffer station, which plays a critical role in the deep-sea mining system. During the transportation of minerals, deep-sea mining pipes can be damaged due to the erosion caused by mineral particles. This paper investigates the erosion characteristics of deep-sea mining transportation pipe based on Eulerian-Lagrangian approach. A computational fluid dynamics (CFD) model for large particle erosion in mining transportation pipe was developed to estimate the effects of mineral particle size, mineral volume concentration, and flow velocity on erosion. It is observed that the maximum erosion rate of pipe shows a decreasing trend, and then slowly increases as the mineral particle size increases. Within a certain range, the maximum erosion rate is positively correlated with mineral concentration and flow velocity. The overall severity of erosion decreases, but the local erosion is still severe. The ends of transportation pipe are subjected to more severe erosion, unlike the conventional 90° elbow pipes where the erosion is lighter in the middle section compared to the sides.