Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Contorno 842 - 7th floor, 30110-060, Belo Horizonte, Brazil.
Water Sci Technol. 2010;61(4):971-7. doi: 10.2166/wst.2010.953.
This article presents results from a performance evaluation of 73 full-scale primary facultative ponds and 37 secondary facultative ponds in Brazil. The data were used to test the applicability of some classical design equations for recommended surface BOD loading rates. The empirical equations proposed by Mara in 1976 and 1987 and the equation developed by McGarry and Pescod in 1970 were evaluated. The loading and hydraulic operating conditions were also evaluated to support the analysis of the influence of the parameters surface BOD loading (L(s)) and hydraulic retention time (HRT) on the performance of the ponds. The results showed that the design equations proposed by Mara showed good applicability for primary facultative ponds, representing good indicators of the limit value of loading rates to be applied on the units. But the secondary facultative ponds showed good and poor performances for all loading rates and the best ponds, in general, were not those which followed the design equations recommendation. Finally, the influence of the actual loading conditions on the ponds performance was very small and scattered, indicating that other unquantified design and operational aspects were playing an important role.
本文介绍了对巴西 73 个全规模一级兼性池塘和 37 个二级兼性池塘的性能评估结果。这些数据用于测试一些经典设计方程在推荐表面 BOD 负荷率方面的适用性。评估了 Mara 于 1976 年和 1987 年提出的经验公式以及 McGarry 和 Pescod 于 1970 年开发的方程。还评估了负荷和水力运行条件，以支持对表面 BOD 负荷（L(s)）和水力停留时间（HRT）参数对池塘性能的影响进行分析。结果表明，Mara 提出的设计方程对一级兼性池塘具有良好的适用性，是应用于单元的负荷率限值的良好指标。但是，二级兼性池塘在所有负荷率下表现良好和较差，一般来说，最好的池塘并不遵循设计方程的建议。最后，实际负荷条件对池塘性能的影响很小且分散，表明其他未量化的设计和操作方面发挥了重要作用。
