El Hamouri B, Rami A, Vasel J L
Wastewater Treatment and Reuse Unit, Institut Agronomique et Vétérinaire Hassan II, BP 6202, Rabat-Instituts, Morocco.
Water Sci Technol. 2003;48(2):269-76.
Results from a tracer study were used to determine and to compare actual and standard (k(20 degrees C)) first order reaction rate constants for COD removal in a High Rate Algal Pond (HRAP) and in 3 facultative ponds (FP) in series. An annual average k(20 degreesC) of 0.123 day(-1) was found for the HRAP while the values of 0.097, 0.025 and 0.003 d(-1) were found for facultative ponds 1, 2 and 3 respectively. Also, comparing nominal and tracer study hydraulic retention times showed large differences for the FP but not for the HRAP indicating that the former were suffering from severe short-circuiting. Loading rate within the range of operation exhibited a positive correlation with k(20 degrees C) for the HRAP but did not show such a relationship for any of the FP. Optimal chlorophyll-a concentration was found to be 3 mg/l for the HRAP and only 1.1 mg/l for the FP. Pollutant specific removal rates (SRR), that translate the hydrodynamic efficiency and the rate of COD biodegradation into pond performance per m2 and per day were calculated. They show that the adoption of the HRAP in place of a series of 3 FP reduces the net land area requirement (LAR) by at least 40%.
一项示踪剂研究的结果被用于测定并比较高速藻类塘（HRAP）和串联的3个兼性塘（FP）中化学需氧量（COD）去除的实际和标准（20℃时的k）一级反应速率常数。HRAP的年平均k（20℃）为0.123天⁻¹，而兼性塘1、2和3的该值分别为0.097、0.025和0.003天⁻¹。此外，比较名义水力停留时间和示踪剂研究水力停留时间发现，兼性塘存在较大差异，而高速藻类塘则没有，这表明前者存在严重的短路现象。在运行范围内的负荷率与HRAP的k（20℃）呈正相关，但对任何一个兼性塘都未显示出这种关系。发现HRAP的最佳叶绿素-a浓度为3毫克/升，而兼性塘仅为1.1毫克/升。计算了污染物特定去除率（SRR），它将水动力效率和COD生物降解速率转化为每平方米每天的池塘性能。结果表明，采用HRAP代替一系列3个兼性塘可使净土地面积需求（LAR）至少减少40%。
