Department of Civil, Environmental and Mechanical Engineering, University of Trento, via Mesiano 77, 38123, Trento, Italy.
Department of Civil, Environmental and Mechanical Engineering, University of Trento, via Mesiano 77, 38123, Trento, Italy.
J Environ Manage. 2020 Jun 1;263:110427. doi: 10.1016/j.jenvman.2020.110427. Epub 2020 Mar 13.
To date, little is known about the start-up of photobioreactors and the progressive development of stable microalgal-bacterial consortia with a view to the full-scale treatment of real wastewater. Two photo-sequencing bioreactors, one inoculated with Chlorella vulgaris (RC) and one with the absence of inoculum (RW), were fed with real municipal wastewater and run in parallel for 101 days. The influence of the inoculation was evaluated in terms of pollutant removal efficiency, excess sludge production, solids settleability and microbial community characteristics. No significant differences were observed in the removal of COD (89 ± 4%; 88 ± 3%) and ammonium (99 ± 1%; 99 ± 1%), mainly associated with bacteria activity. During the first weeks of acclimation, Chlorella vulgaris in RC promoted better P removal and very high variations of DO and pH. Conversely, under steady-state conditions, no significant differences were observed between the performances of RC and RW, showing good settleability and low effluent solids, 7 ± 8 and 13 ± 10 mg TSS/L respectively. Microbiome analysis via 16S rRNA gene sequencing showed that, despite a different evolution, the microbial community was quite similar in both reactors under steady state conditions. Overall, the results suggested that the inoculation of microalgae is not essential to engender a photobioreactor aimed at treating real municipal wastewater.
迄今为止，人们对光生物反应器的启动以及稳定的微藻-细菌共生体的逐步发展知之甚少，而这是全面处理实际废水的关键。本研究采用两种光测序生物反应器，一种接种了普通小球藻（RC），另一种未接种（RW），并用实际的城市污水进行连续 101 天的平行处理。通过评估污染物去除效率、剩余污泥产量、固体沉降性和微生物群落特征，评估接种的影响。COD（89±4%；88±3%）和铵（99±1%；99±1%）的去除率没有显著差异，主要与细菌活性有关。在驯化的最初几周，RC 中的普通小球藻促进了更好的磷去除和 DO 和 pH 值的非常高的变化。相反，在稳定状态下，RC 和 RW 的性能没有明显差异，表现出良好的沉降性和低的出水固体，分别为 7±8 和 13±10 mg TSS/L。通过 16S rRNA 基因测序进行的微生物组分析表明，尽管进化过程不同，但在稳定状态下，两个反应器中的微生物群落非常相似。总的来说，结果表明，接种微藻对于处理实际城市污水的光生物反应器来说并非必不可少。
