Univerisity of Vale do Itajaí, Rua Uruguai, 458. Itajaí-SC. 88.203-202, Brazil.
Water Sci Technol. 2013;67(8):1832-40. doi: 10.2166/wst.2013.063.
An outfall 1,800 m long was initially proposed by CASAN (Water and Sanitation Company of Santa Catarina) to dispose of treated domestic residual water effluent from Praia dos Ingleses beach. The final plan average flow, estimated for the summer season is 0.1543 m³/s. The characteristics on the near field of the diffuser were calculated using the NRFIELD model supplied by a series of current profiles and density, gathered at the diffuser location between March and April, 2007. Reliable information of raw sewage fecal coliform concentration and nutrients has been supplied by CASAN, based on continuous monitoring of sewage in its treatment plants. The diffuser was designed in such a way that it maximizes the initial dilution allowing the nutrients concentration to comply with legislation limits. However, results showed that the treatment plant should be designed to mainly reduce total phosphorus. A hydrodynamic model was implemented to generate current fields for the far field modeling. Information gathered in the field on variation in water level, wind, and current velocity and direction was used for boundary and/or initial conditions. Then, a Lagrangian advective-diffusive model was used to evaluate the extent of the plumes. The results of far field modeling showed a need to increase the outfall length. A new location 3,300 m from the beach has been proposed.
一个 1800 米长的排水口最初是由 CASAN（圣卡塔琳娜州的水和卫生公司）提出的，用于处理来自英吉利斯海滩的处理后的家庭剩余水废水。根据夏季的估计，最终计划的平均流量为 0.1543 立方米/秒。使用 NRFIELD 模型计算了扩散器近场的特性，该模型由 2007 年 3 月至 4 月在扩散器位置收集的一系列电流剖面和密度提供。根据其处理厂对污水的连续监测，CASAN 提供了原始污水粪大肠菌群浓度和营养物的可靠信息。扩散器的设计方式最大限度地提高了初始稀释度，从而使营养物浓度符合法规限制。然而，结果表明，处理厂的设计应主要用于减少总磷。实施了水动力模型以生成远场模型的水流场。现场收集的水位、风和水流速度和方向的变化信息用于边界和/或初始条件。然后，使用拉格朗日对流-扩散模型来评估羽流的范围。远场建模的结果表明需要增加排水口的长度。已经提出了一个距离海滩 3300 米的新位置。
