Environmental impact of sewage sludge co-digestion with food waste and fat-oil-grease: Integrating plant-wide modeling with life cycle assessment approach

Filiz Daskiran; Hazal Gulhan; Emircan Kara; Huseyin Guven; Hale Ozgun; Mustafa Evren Ersahin

doi:10.1016/j.biortech.2023.130198

Environmental impact of sewage sludge co-digestion with food waste and fat-oil-grease: Integrating plant-wide modeling with life cycle assessment approach

Bioresour Technol. 2024 Feb:394:130198. doi: 10.1016/j.biortech.2023.130198. Epub 2023 Dec 15.

Authors

Filiz Daskiran¹, Hazal Gulhan², Emircan Kara³, Huseyin Guven⁴, Hale Ozgun⁵, Mustafa Evren Ersahin⁶

Affiliations

¹ Istanbul Technical University, Environmental Engineering Department, Maslak, 34469, Istanbul, Turkey. Electronic address: ozturkfi@itu.edu.tr.
² Istanbul Technical University, Environmental Engineering Department, Maslak, 34469, Istanbul, Turkey. Electronic address: gulhan@itu.edu.tr.
³ Istanbul Technical University, Environmental Engineering Department, Maslak, 34469, Istanbul, Turkey. Electronic address: karaemir@itu.edu.tr.
⁴ Istanbul Technical University, Environmental Engineering Department, Maslak, 34469, Istanbul, Turkey. Electronic address: guvenhu@itu.edu.tr.
⁵ Istanbul Technical University, Environmental Engineering Department, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, Maslak 34469, Istanbul, Turkey. Electronic address: ozgunha@itu.edu.tr.
⁶ Istanbul Technical University, Environmental Engineering Department, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, Maslak 34469, Istanbul, Turkey. Electronic address: ersahin@itu.edu.tr.

PMID: 38103751
DOI: 10.1016/j.biortech.2023.130198

Abstract

Anaerobic co-digestion of fat-oil-grease (FOG) and food waste (FW) with sewage sludge (SS) in wastewater treatment plants is a method used to increase biogas production. In this study, digestion scenarios were compared using plant-wide modeling and life cycle assessment: Scenario-0 (mono-digestion of waste-activated sludge (WAS)), Scenario-1 (co-digestion of WAS with FOG), and Scenario-2 (co-digestion of WAS with FW). Scenario-0, with the highest energy use and landfilling of FOG/FW, has the worst environmental impact. Scenario-1 and Scenario-2 minimize the environmental load by energy recovery and avoiding landfilling of organic waste. Scenario-wise, the change in greenhouse gas (GHG) emissions from treatment was negligible. However, due to the impact of landfilling, GHG emissions in Scenario-0 were 21% and 30% higher than in Scenario-1 and 2, respectively. The environmental benefit of anaerobic co-digestion of FOG/FW with SS is not only in the contribution to energy production but also in the recycling of organic waste.

Keywords: Anaerobic co-digestion; Biological modeling; Environmental assessment; Landfilling; Organic waste.

MeSH terms

Anaerobiosis
Animals
Biofuels / analysis
Bioreactors
Digestion
Food
Food Loss and Waste
Greenhouse Gases*
Hydrocarbons
Life Cycle Stages
Methane / analysis
Refuse Disposal*
Sewage

Substances

Sewage
Food Loss and Waste
Methane
Hydrocarbons
Biofuels
Greenhouse Gases