The Hydraulics of Waste Stabilization Ponds. Part I. The Effect of Hydraulic Flow Characteristics on Treatment Efficiency. Part II. The Effect of Wind Mixing in Stratified and Unstratified Ponds.

摘要

The treatment efficiency of waste stabilization ponds can be influenced significantly by the hydraulic flow patterns within the ponds. To evaluate the effects of shape and depth of the ponds,placement of inlets and outlets, baffling and density stratification an hydraulic model of the prototype Logan City ponds was constructed. The mixing properties of the model ponds were evaluated by injecting a slug of rhodamine WT dye into the inflow and measuring the dye concentration vs time at the outlet. A mathematical (finite-stage) model of the mixing process was adapted to stabilization ponds to determine if a more theoretical design was feasible. A wind-water tunnel was constructed to simulate a wind-over-water situation. A relationship between wind velocity and surface shear stress was established. Diffusion coefficients describing the wind driven mixing of an injected dye were evaluated as functions of the surface shear-velocity Reynolds number.