The study addressed the need for sustainable greywater treatment, aiming to mitigate water scarcity and pollution. The potential of using microalgae cultivated in greywater with zinc oxide nanoparticles (ZnO/GAC-nanocomposite) was investigated for these purposes. A batch photobioreactor was employed for 15 d. The nanocomposite system significantly improved nutrient removal, with optimal removal efficiency of 80 % for TOC, 94.2 % for PO43−, and 99.6 % for NH4+. The presence of nanocomposites improved microalgae growth, achieving a density of 1.8 g/L compared to 0.83 g/L without nanocomposites. The microalgal biomass obtained had a high volatile matter content of 74.4 %, low ash content of 5.1 %, and fixed carbon of 20.4 %. The biomass includes 46.74 % carbon, 5.72 % hydrogen, and 38.75 % oxygen, with a high heating value of 18.32 MJ/kg. The reusability of ZnO/GAC-nanocomposite was also assessed, which maintained effective nutrient removal after four cycles, with NH4+, PO43−, and TOC removal rates of 86.1 %, 83.2 %, and 69.8 %, respectively. Comparison of treated greywater with a pH of 8.5, turbidity <4 NTU, COD, NH4+, PO43− of 34, 0.032, and 0.48 mg/L, respectively, with various reuse standards, indicated its potential reuse for toilet flushing.

中文翻译：

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用于灰水处理的混养微藻和 Zno/GAC 纳米复合系统


该研究解决了可持续灰水处理的需求，旨在缓解水资源短缺和污染。为此，我们研究了使用在灰水中培养的微藻和氧化锌纳米颗粒（ZnO/GAC-纳米复合材料）的潜力。使用间歇式光生物反应器15天。纳米复合系统显着改善了养分去除效果，TOC 的最佳去除效率为 80%，PO43− 的最佳去除效率为 94.2%，NH4+ 的最佳去除效率为 99.6%。纳米复合材料的存在改善了微藻的生长，密度达到了 1.8 克/升，而没有纳米复合材料时密度为 0.83 克/升。所得微藻生物质挥发分含量高，为74.4%，灰分含量低，为5.1%，固定碳为20.4%。生物质含碳46.74%、氢5.72%、氧38.75%，热值高达18.32 MJ/kg。 ZnO/GAC-纳米复合材料的可重复使用性也得到了评估，在四个循环后仍保持有效的养分去除，NH4+、PO43−和TOC去除率分别为86.1%、83.2%和69.8%。将 pH 为 8.5、浊度 <4 NTU、COD、NH4+、PO43− 分别为 34、0.032 和 0.48 mg/L 的处理后灰水与各种回用标准进行比较，表明其回用于冲厕的潜力。