Novel routes for urban bio-waste management: A combined acidic fermentation and anaerobic digestion process for platform chemicals and biogas production

JOURNAL OF CLEANER PRODUCTION

卷:220

Article

Valentino, Francesco¹  Moretto, Giulia²  Gottardo, Marco²  Pavan, Paolo²  Bolzonella, David³  Majone, Mauro¹ 

[1] Univ Roma La Sapienza, Dept Chem, Ple Aldo Moro 5, I-00185 Rome, Italy

[2] Dept Environm Sci Informat & Stat, Via Torino 155, I-30170 Venice, Italy

[3] Univ Verona, Dept Biotechnol, Str Le Grazie 15, I-37134 Verona, Italy

关键词: Anaerobic digestion;    OFMSW;    Waste activated sludge (WAS);    Renewable feedstock;    Biogas;    Volatile fatty acid (VFA);   

DOI  :  10.1016/j.jclepro.2019.02.102

来源: Elsevier

【 摘 要 】

A combined acidic fermentation and anaerobic digestion (AD) treatment has been developed on pilot scale for urban bio-waste conversion into volatile fatty acid (VFA) and biogas. The specific waste mixture was composed by the pre-treated organic fraction of municipal solid waste (OFMSW) and waste activated sludge (WAS), both produced inside the Treviso (northeast Italy) municipality. The effect of temperature (37 degrees C and 55 degrees C) was investigated in both steps. Only the mesophilic fermentation process provided a VFA-rich stream (19.5g CODVFA/L) with stable physical-chemical features, with no need of chemicals addition for pH control. The sludge buffering capacity made this step technically feasible. The AD step was performed on the solid-rich fraction of fermented bio-waste, after dilution with excess WAS. No relevant differences were observed under the two investigated temperature: in the steady state (organic loading rate of 2.5 kg VS/m(3) d), the specific biogas production was 0.40 and 0.45 m(3)/kg VS at 37 degrees C and 55 degrees C respectively, with similar CH4 content (63-64% v/v). The scaled-up version of the system (in an average urban municipality of 170,000 Person Equivalent) revealed that the whole process is thermally sustainable if both reactors are operated at mesophilic temperature: 36% of surplus thermal energy and 13,03 MWh/d of produced electricity, which corresponds to a revenue of 609,605 (sic)/year. In addition, 2,262 kg CODVFA/d are available for parallel purposes, such as the synthesis of bio-products with higher added value than bio-methane (e.g. biopolymers). (C) 2019 Elsevier Ltd. All rights reserved.

【 授权许可】

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