An innovative multistage treatment system for sanitary landfill leachate depuration: Studies at pilot-scale

• Type: Article in International Scientific Journal
• Date: 2017

Authors

Vítor J. P. Vilar (Author) FEUP; Tânia F. C. V. Silva (Author) FEUP; Petrick A. Soares (Author) FEUP; Diego R. Manenti (Author) FEUP; Amélia Fonseca (Author) Other; Isabel Saraiva (Author) Other; Rui A. R. Boaventura (Author) FEUP

Journal

Title: Science of the Total Environment

Vol. 576

Pages: 99-117

ISSN: 0048-9697

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 21 Citations

ISI Web of Science

Scopus - 40 Citations

Scientific classification

CORDIS: Technological sciences > Technology > Environmental technology

FOS: Engineering and technology > Environmental engineering

Associated Projects

LSRE-LCM - Laboratório de Processos de Separação e Reação - Laboratório de Catálise e Materiais

AdvancedLFT - Tecnologia de tratamento de lixiviados de aterros sanitários através da integração de processos de oxidação biológica e foto oxidação química, combinando radiação solar natural e artificial

Other information

Authenticus ID: P-00M-69H

DOI: 10.1016/j.scitotenv.2016.10.058

Abstract (EN): In this work, an innovative methodology for the treatment of landfill leachates, after aerobic lagooning, is proposed and adjusted at pilot-scale. This methodology involves an aerobic activated sludge biological pre-oxidation (ASBO), a coagulation/sedimentation step (240 mg Fe3+/L, at pH 4.2) and a photo-oxidation through a photo-Fenton (PF) reaction (60 mg Fe2+, at pH 2.8) combining solar and artificial light. The ASBO process applied to a leachate after aerobic lagooning, with high organic and nitrogen content (1.1-1.5 g C/L; 0.8-3.0 g N/L) and low biodegradability (BOD5/COD = 0.07-0.13), is capable to oxidise 62-99% of the ammonium nitrogen, consuming only the affluent alkalinity (70-100%). The coagulation/sedimentation stage led to the humic acids precipitation, promoting a marked change in leachate colour,from dark-brown to yellowish-brown (related to fulvic acids), accompanied by a reduction of 60%, 58% and 88% on DOC, COD and TSS, respectively. The PF system promoted the degradation of the recalcitrant organic molecules into more easily biodegradable ones. According to Zahn-Wellens biodegradability test, a leachate with 419 mg DOC/L after coagulation, would have to be photo-oxidized until DOC <256 mg/L, consuming 117 mM of H2O2 and 10.4 kJ/L of accumulated UV energy, to achieve an effluent that can be biologically treated in compliance with the COD discharge limit (150 mg O-2/L) into water bodies. The biological process downstream from the photocatalytic system would promote a mineralization >60%. The PF step cost to treat 100 m(3)/day of leachate was 6.41sic/m(3), combining 1339 m(2) of CPCs with lamps.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 19