Structural optimization for an axial oil‐water separator with multi‐stage separation

In order to meet the demand of industrial production, an axial separator for oil-water separation is proposed. The separator uses the pattern of multi-stage separation, and it is divided into two chambers by two swirl impellers. The oil phase flows out through three Light Phase Outlet (LPO) at the center of the impeller hub, meanwhile the water phase flows out through Heavy Phase Outlet (HPO). An experimental platform was built to verify the feasibility of multi-stage separation. The Mixture model and Reynolds stress model was used to simulate the separation process, and the numerical results had a well agreement with experimental results. The effects of the diameter of cylindrical section, length of conical section and length of separation chamber on the separation performance were studied. The results show that: changing the diameter of cylindrical section has greatest impact on separation performance. The separation efficiency and pressure drop first increase and then decrease with increase of primary conical section length. With increase of second conical section length, the separation performance has been increasing. If it only looks at the relationship between pressure drop and separation efficiency, then there is a pressure drop to maximize the separation efficiency. Changing the diameter of cylindrical section can adjust the flow split LPO s . Increasing the length of second conical section can increase the split ratio of LPO 3 , but it has almost no effect on the total split ratio of LPO s . the value of structure is determined and the efficiency of separator exceeds 93 %.