Coupling of acrylic dyeing wastewater treatment by heterogeneous Fenton oxidation in a continuous stirred tank reactor with biological degradation in a sequential batch reactor

• Type: Article in International Scientific Journal
• Date: 2016

Authors

Bruno M. Esteves (Author) FEUP; Carmen S. D. Rodrigues (Author) FEUP; Rui A. R. Boaventura (Author) FEUP; F. J. Maldonado-Hodar (Author) Other; Luís M. Madeira (Author) FEUP

Journal

Title: Journal of Environmental Management

Vol. 166

Pages: 193-203

ISSN: 0301-4797

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 36 Citations

Scopus - 63 Citations

Associated Projects

LEPABE - Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia

LEPAE/CEFT - RL2 - (Bio) Chemical Engineering: Multi-Scale Approaches for Sustainable Environment and Health

Other information

Authenticus ID: P-00G-T52

DOI: 10.1016/j.jenvman.2015.10.008

Abstract (EN): This work deals with the treatment of a recalcitrant effluent, from the dyeing stage of acrylic fibres, by combination of the heterogeneous Fenton's process in a continuous stirred tank reactor (CSTR) with biological degradation in a sequential batch reactor (SBR). Three different catalysts (a commercial Fe/ZSM-5 zeolite and two distinct Fe-containing activated carbons - ACs - prepared by wet impregnation of iron acetate and iron nitrate) were employed on the Fenton's process, and afterwards a parametric study was carried out to determine the effect of the main operating conditions, namely the hydrogen peroxide feed concentration, temperature and contact time. Under the best operating conditions found, using the activated carbon impregnated with iron nitrate, 62.7% of discolouration and 39.9% of total organic carbon (TOC) reduction were achieved, at steady-state. Furthermore, a considerable increase in the effluent's biodegradability was attained (BOD5:COD ratio increased from <0.001 to 0.27 and SOUR - specific oxygen uptake rate from <0.2 to 11.1 mg O-2/(gvss.h)), alongside a major decrease in its toxicity (from 92.1 to 94.0% of Vibrio fischeri inhibition down to 6.9-9.9%). This allowed the application of the subsequent biological degradation stage. The combination of the two processes provided a treated effluent that clearly complies with the legislated discharge limits. It was also found that the iron leaching from the three catalysts tested was very small in all runs, a crucial factor for the stability and long-term use of such materials.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11