Computational study of flow characteristics of acid mine drainage on the structure of oxidation pond

A computational flow analysis using the concept of the inflow age was conducted to evaluate the flow characteristics and retention time depending on the shape and number of inlets and outlets in an oxidation pond. The oxidation pond was rectangular in shape with a width‐to‐length ratio of 3, a depth of 3 m, an area of 500 m², and square‐shaped inlet and outlet. The flow rate of the mine drainage was set to 5 L/s. The computational flow analysis showed that the homogeneity and inflow exchange efficiency were the highest when the width‐to‐height ratio of the inlet and outlet was 0.5, while they were the lowest when it was 1.0. The number of inlets in the oxidation pond had a significant effect on the flow characteristics in the pond, whereas the number of outlets had no significant effect. The homogeneity and inflow exchange efficiency appeared to be the highest when the number of inlets was two.