Biochemical methane potential of fractions of organic matter extracted from a municipal solid waste leachate: Impact of their hydrophobic character. (May 2017)

• Record Type: Journal Article
• Authors: Baccot, Camille; Pallier, Virginie; Feuillade-Cathalifaud, Geneviève
• Is Part Of: Waste management. Volume 63(2017)
• Page Start: 257
• Page End: 266
• Publication Date: 2017-05
• Subjects: Municipal solid waste leachate -- Organic matter -- Hydrophobic character -- BMP -- Experimental design; AD anaerobic digestion -- BMP biochemical methane potential -- BOD biological oxygen demand -- CMY cumulative methane yield -- COD chemical oxygen demand -- DOM dissolved organic matter -- FA* fulvic-like acids -- HA* humic-like acids -- HPI* hydrophilic-like compounds -- HPO* hydrophobic-like compounds -- MWTP municipal wastewater treatment plant -- SUVA specific ultra-violet absorbance -- TPH* transphilic-like compounds -- VFA volatile fatty acids -- VS volatile solids -- VSS volatile suspended solids; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2016.11.025
• Languages: English
• ISSNs: 0956-053X

Abstract

Highlights: Development of a biochemical methane potential test adapted to waste leachate. Evaluation of the BMP of MSWL and description of the anaerobic evolution of the OM. Impact of the hydrophobic character of the OM on biogas and methane production. Abstract: Many data on anaerobic digestion (AD) and co-digestion of municipal solid waste leachate (MSWL) are already available in literature. They mainly deal with its performances to decrease the chemical oxygen demand (COD) of MSWL and no information is given on the impact of the specific characteristics of the dissolved organic matter (DOM) in leachate on these performances. DOM in leachate evolves towards more aromatic and hydrophobic compounds during landfilling with increasing specific ultra-violet absorbance index (SUVA) and hydrophobic character. However, according to the humification stages, this DOM would not present the same aptitude for AD. This research thus focused on (i) optimizing a biochemical methane potential (BMP) test applied to MSWL by using the Taguchi method and (ii) evaluating the impact of the hydrophobic character of the DOM in leachate on the BMP of MSWL to finally define the humification degree more suitable for AD. Hydrophobic-like (HPO ∗ ) and transphilic-like (TPH ∗ ) compounds extracted from leachate by a fractionation protocol were tested because of their high content in MSWL during acetogenesis and methanogenesis steps. After 275 days of AD, the content in hydrophobic compounds and the SUVA indexes increased in the digestates. Moreover, even if the biogas and methane productions were not significantly different during the whole tests (4072 ± 350 mL gDOC −1 and 2370 ± 95 mL gDOC −1 respectively), the volume of biogas produced directly correlated with the TPH ∗ fraction content in the initial digestates. On the contrary, the methane percentage in biogas was anti-correlated with the hydrophilic-like compounds content. The hydrophobic-like molecules seem thus not to be directly involved in the methanogenic step, however they promote the increase of the methane percent in the biogas.