Reactive Orange 16 dye degradation in anaerobic and aerobic MBBR coupled with ozonation: addressing pathways and perform
- PDF / 1,392,964 Bytes
- 20 Pages / 595.276 x 790.866 pts Page_size
- 72 Downloads / 179 Views
ORIGINAL PAPER
Reactive Orange 16 dye degradation in anaerobic and aerobic MBBR coupled with ozonation: addressing pathways and performance F. D. Castro1 · J. P. Bassin1 · T. L. M. Alves1 · G. L. Sant’Anna Jr.1 · M. Dezotti1 Received: 11 May 2020 / Revised: 13 August 2020 / Accepted: 7 October 2020 © Islamic Azad University (IAU) 2020
Abstract In this study, two treatment routes were investigated for degradation of the azo dye Reactive Orange 16 (RO16): biodegradation in an anaerobic MBBR (R1) and ozonation followed by biological treatment in an aerobic MBBR (R2). Along with the dye, glucose and nutrients were supplemented to the influent fed to R1 as carbon co-substrate and nitrogen source, respectively. In R1, maximum color removal of 61 ± 18% was achieved for 5 mg l−1 of dye, hydraulic retention time of 12 h and influent COD of 800 mg l−1. Moreover, RO16 biodegradation was limited by carbon source (glucose) and attached solids concentrations. Batch tests revealed that anaerobic biodegradation of the dye and glucose followed second-order kinetics and RO16 degradation constant increased as the initial COD was reduced. Considering the relatively low color removal achieved anaerobically, dye solutions (100 to 500 mg l−1) were ozonated, enabling fast discoloration of at least 97% within 20 min for the highest dye concentration. However, the low COD (50–75%) and TOC (35–40%) removals achieved indicate that only partial mineralization occurred. RO16 (500 mg l−1) ozonation products were identified, and a degradation pathway was proposed. Subsequently, the ozonated solutions were supplemented with glucose and nutrients and fed to R2. COD removal decreased considerably (from 92 to 81%) when ozonated solutions with original dye concentration of 500 mg l−1 were fed to R2, but ammonium removal remained fairly stable. Three compounds identified before biological treatment were not found in R2 effluent, suggesting that they were biodegraded. Keywords Color removal · Oxidative process · Bioprocess · By-products · Metabolization · Mechanism
Introduction The economic relevance of the textile industry has already been highlighted by several authors, who also underlined the environmental impacts caused by the wastewaters generated by this industrial segment, particularly by dyes (Allègre et al. 2006; Ghaly et al. 2014). As they are not entirely incorporated into fabrics, the dyes confer high levels of color
Editorial responsibility: Samareh Mirkia. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s13762-020-02983-8) contains supplementary material, which is available to authorized users. * J. P. Bassin [email protected] 1
Chemical Engineering Program/COPPE, Federal University of Rio de Janeiro, P.O. Box 68502, Rio de Janeiro 21941‑972, Brazil
to the textile wastewaters and pose serious risks to human health (Mishra and Maiti 2018). The big variety of dyes and their complex structures may render treatment rather difficult. The molecules of organic dyes are characte
Data Loading...
