Taghilou Samaneh, Peyda Mazyar, Mehrasbi Mohammad Reza
Department of Environmental Health Engineering, School of Public Health, Zanjan University of Medical Sciences, Zanjan, Iran.
J Environ Health Sci Eng. 2021 Sep 14;19(2):1723-1733. doi: 10.1007/s40201-021-00727-5. eCollection 2021 Dec.
Due to the population growth and reduction of water resources, wastewater treatment and reuse vital. As the secondary wastewater treatment processes enable removes a significant amount of P and N, nutrient-rich effluents can cause eutrophication in water bodies. On the other hand, nutrients removal in sewage treatment using mechanical methods is costly and complex. The aquaculture method using could be an appropriate option for removing total phosphorus (TP), total nitrogen (TN), and chemical oxygen demand (COD) from wastewater.
Synthetic wastewater has been prepared in the typical range of municipal wastewater. Two g fresh weight of an acclimatized was floated in sample bowls each one containing 500 CC prepared wastewater. Total nitrogen, TP, and COD removal by for 21-days were optimized and investigated using the response surface methodology (RSM). For this aim, the D-optimal method was used to optimize the three independent variables (TP concentration (10.8-84.6 mg l), TN concentration (20-99 mg l), and COD concentration (66.26-415 mg l)) for their maximum removal efficiency of them. Experiments were performed on 28 runs in which independent variables were measured using a HACH DR 5000 spectrometer.
Predicted R-squared for COD, TP, TN removal, and mass (responses) have been equal to -0.0897, 0.8514, 0.7779, and 0.5645, respectively. The model was used to maximize growth and maximize removal efficiency of nitrogen, phosphorus, and COD that occurred in minimum concentrations of TN (20 mg l), TP (10.8 mg l), and COD (66.26 mg l). The removal efficiency of was obtained 77.5 % for COD, 66.8 % for TP, and 78.1 % for TN in the optimum condition of independent variables. Also, increase of mass was 239 %, with desirability of 0.66. The difference between model prediction and model validation testing for mass increase, COD, TN, and TP removal was equal to ± 11.6 %, ± 7.9 %, ± 0.0 %, and ± 1.9 %, respectively.
could remove phosphorus in nitrogen deficiency or even lack of nitrogen. Results indicate that removal efficiency has an upward trend as the growth increases. This kind of fern has a significant effect on removing nitrogen, phosphorus, and COD from an aqueous solution. The removal efficiency of TN, TP, and COD at optimum operating conditions showed good agreement with model-predicted removal efficiency.
由于人口增长和水资源减少，废水处理与回用至关重要。二级废水处理工艺虽能去除大量的磷和氮，但富含营养物质的废水会导致水体富营养化。另一方面，采用机械方法去除污水处理中的营养物质成本高且复杂。利用水产养殖方法可能是从废水中去除总磷（TP）、总氮（TN）和化学需氧量（COD）的合适选择。
在城市废水的典型范围内配制了合成废水。将两克鲜重的驯化[具体物种未提及]漂浮在每个装有500毫升配制废水的样品碗中。使用响应面法（RSM）对[具体物种未提及]在21天内对总氮、总磷和化学需氧量的去除进行了优化和研究。为此，采用D-最优法对三个自变量（总磷浓度（10.8 - 84.6毫克/升）、总氮浓度（20 - 99毫克/升）和化学需氧量浓度（66.26 - 415毫克/升））进行优化，以实现它们的最大去除效率。进行了28次实验，其中使用哈希DR 5000光谱仪测量自变量。
化学需氧量、总磷、总氮去除率以及[具体物种未提及]质量（响应值）的预测决定系数分别为-0.0897、0.8514、0.7779和0.5645。该模型用于使[具体物种未提及]生长最大化以及在总氮（20毫克/升）、总磷（10.8毫克/升）和化学需氧量（66.26毫克/升）的最低浓度下使氮、磷和化学需氧量的去除效率最大化。在自变量的最佳条件下，[具体物种未提及]对化学需氧量的去除效率为77.5%，对总磷的去除效率为66.8%，对总氮的去除效率为78.1%。此外，[具体物种未提及]质量增加了239%，可取性为0.66。[具体物种未提及]质量增加、化学需氧量、总氮和总磷去除的模型预测与模型验证测试之间的差异分别为±11.6%、±7.9%、±0.0%和±1.9%。
[具体物种未提及]在缺氮甚至无氮的情况下也能去除磷。结果表明，随着[具体物种未提及]生长增加，去除效率呈上升趋势。这种蕨类植物对从水溶液中去除氮、磷和化学需氧量有显著影响。在最佳运行条件下，总氮、总磷和化学需氧量的去除效率与模型预测的去除效率显示出良好的一致性。
