... enhance recovery ratio. The filter was awarded national prize. Now, series of walnut shell filters with various backwash methods and capacities ... /m2s6.3Design pressure, MPa0.62.0Design temperature,ºC 80 Filter velocity, m/h2434Backwash time, min.2025Filter resistance (single ... 100Oil content≤10Working cycle, h825Filter resistance (2 stages, in series), MPa13%Inlet water, mg/LSS ≤50Oil≤50Outlet water, ...