Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran.
Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran.
Chemosphere. 2018 Dec;213:197-204. doi: 10.1016/j.chemosphere.2018.09.047. Epub 2018 Sep 8.
A high rate up-flow anaerobic, anoxic and oxic (AO) bioreactor was designed and operated for meat-processing wastewater (MPW) treatment as a single cost-effective system with the aim of simultaneous CNP removal. The influence of three essential factors, HRT, COD/TN ratio and aerated volume fraction on the reactor performance was assessed using response surface methodology (RSM). The required HRT to reach 98.5% COD removal was achieved at 7.5 h. Simultaneous CNP removal under denitrification rate of 199.4 mg/l.d gave high nitrate to nitrogen gas conversion of 74.6 mg/l. An HRT, COD/TN ratio and aerated volume fraction of 10 h, 100:20 and 60%, respectively, was a favored condition for an efficient nitrogen removal with effluent total Kjeldahl nitrogen (TKN) less than 70 mg/l. Under optimum condition, an HRT, COD/TN and aerated volume fraction of 8 h, 100:14 and 65%, respectively, resulted an effluent phosphorus of 43 mg/l, but 93.97 mg/l phosphorus was released in an anaerobic condition at 6 h. An effluent with a low turbidity of about 1.5 NTU and a sludge volume index (SVI) of 75.9 ml/g was achieved using at HRT of 12.5 h, COD/TN ratio of 100: 8 and aerated volume fraction of 50%. Under these conditions, the removal efficiencies for COD, TKN, nitrate-nitrogen (NO-N), total nitrogen (TN) and phosphorus (PO-P) were obtained to be 98.33, 92.06, 91.97, 90.48 and 83.48%, respectively. As a result, the application of the up-flow AO bioreactor is a promising configuration to get hygienic water from wastewater.
一个高效的上流式厌氧-缺氧-好氧（AO）生物反应器被设计并应用于肉类加工废水（MPW）处理，作为一个单一的具有成本效益的系统，旨在同时去除 CNP。使用响应面法（RSM）评估了三个重要因素，即水力停留时间（HRT）、COD/TN 比和曝气体积分数对反应器性能的影响。达到 98.5%COD 去除率所需的 HRT 为 7.5 小时。在 199.4mg/l.d 的反硝化速率下同时去除 CNP，硝酸盐到氮气的转化率高达 74.6mg/l。HRT、COD/TN 比和曝气体积分数分别为 10h、100:20 和 60%，是实现高效氮去除的有利条件，出水总凯氏氮（TKN）小于 70mg/l。在最佳条件下，HRT、COD/TN 和曝气体积分数分别为 8h、100:14 和 65%，出水磷为 43mg/l，但在 6h 厌氧条件下释放了 93.97mg/l 的磷。在 HRT 为 12.5 小时、COD/TN 比为 100:8 和曝气体积分数为 50%的条件下，出水浊度约为 1.5 NTU，污泥体积指数（SVI）为 75.9ml/g。在这些条件下，COD、TKN、硝酸盐氮（NO-N）、总氮（TN）和磷（PO-P）的去除效率分别达到 98.33%、92.06%、91.97%、90.48%和 83.48%。因此，上流式 AO 生物反应器的应用是从废水中获得卫生用水的一种很有前途的配置。
