Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar 32610, Perak Darul Ridzuan, Malaysia; Department of Civil Engineering, Abubakar Tafawa Balewa University, Bauchi, Nigeria.
Department of Civil Engineering, Abubakar Tafawa Balewa University, Bauchi, Nigeria; Department of Civil and Environmental Engineering, University of Strathclyde, Glasgow, UK.
Chemosphere. 2023 Oct;339:139620. doi: 10.1016/j.chemosphere.2023.139620. Epub 2023 Jul 29.
Agro-industrial biorefinery effluent (AIBW) is considered a highly polluting source responsible for environmental contamination. It contains high loads of chemical oxygen demand (COD), and phenol, with several other organic and inorganic constituents. Thus, an economic treatment approach is required for the sustainable discharge of the effluent. The long-term process performance, contaminant removal and microbial response of AIBW to rice straw-based biochar (RSB) and biochar-based geopolymer nanocomposite (BGC) as biosorbents in an activated sludge process were investigated. The adsorbents operated in an extended aeration system with a varied hydraulic retention time of between 0.5 and 1.5 d and an AIBW concentration of 40-100% for COD and phenol removal under standard conditions. Response surface methodology was utilised to optimize the process variables of the bioreactor system. Process results indicated a significant reduction of COD (79.51%, 98.01%) and phenol (61.94%, 74.44%) for BEAS and GEAS bioreactors respectively, at 1 d HRT and AIBW of 70%. Kinetic model analysis indicated that the Stover-Kincannon model best describes the system functionality, while the Grau model was better in predicting substrate removal rate and both with a precision of between R (0.9008-0.9988). Microbial communities examined indicated the abundance of genera, following the biosorbent addition, while RSB and BGC had no negative effect on the bioreactor's performance and bacterial community structure of biomass. Proteobacteria and Bacteroidetes were abundant in BEAS. While the GEAS achieved higher COD and phenol removal due to high Nitrosomonas, Nitrospira, Comamonas, Methanomethylovorans and Acinetobacter abundance in the activated sludge. Thus, this study demonstrated that the combination of biosorption and activated sludge processes could be promising, highly efficient, and most economical for AIBW treatment, without jeopardising the elimination of pollutants or the development of microbial communities.
农业工业生物精炼厂废水（AIBW）被认为是一种高度污染的污染源，会造成环境污染。它含有高浓度的化学需氧量（COD）和苯酚，以及其他一些有机和无机成分。因此，需要采用经济的处理方法来实现废水的可持续排放。本研究考察了 AIBW 在活性污泥工艺中作为生物吸附剂对水稻秸秆基生物炭（RSB）和生物炭基地质聚合物纳米复合材料（BGC）的长期过程性能、污染物去除和微生物响应。在标准条件下，吸附剂在扩展曝气系统中运行，水力停留时间（HRT）为 0.5-1.5 d，AIBW 浓度为 40-100%，用于 COD 和苯酚去除。利用响应面法优化了生物反应器系统的工艺变量。工艺结果表明，在 1 d HRT 和 AIBW 为 70%的条件下，BEAS 和 GEAS 生物反应器的 COD（79.51%、98.01%）和苯酚（61.94%、74.44%）去除率显著降低。动力学模型分析表明，Stover-Kincannon 模型最能描述系统功能，而 Grau 模型更能预测基质去除率，两者的精度均在 R（0.9008-0.9988）之间。微生物群落分析表明，生物吸附剂添加后，生物量中的属丰度增加，而 RSB 和 BGC 对生物反应器的性能和细菌群落结构没有负面影响。在 BEAS 中，变形菌门和拟杆菌门丰度较高。而由于活性污泥中硝化菌属、硝化螺菌属、丛毛单胞菌属、甲烷甲基杆菌属和不动杆菌属丰度较高，GEAS 实现了更高的 COD 和苯酚去除率。因此，本研究表明，生物吸附与活性污泥工艺相结合，对 AIBW 处理具有很高的效率和经济性，且不会对污染物的去除或微生物群落的发展造成危害。
