Assessing the climate change mitigation potential from food waste composting

Abstract

Food waste is a dominant organic constituent of landfills, and a large global source of greenhouse gases. Composting food waste presents a potential opportunity for emissions reduction, but data on whole pile, commercial-scale emissions and the associated biogeochemical drivers are lacking. We used a non-invasive micrometeorological mass balance approach optimized for three-dimensional commercial-scale windrow compost piles to measure methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) emissions continuously during food waste composting. Greenhouse gas flux measurements were complemented with continuous oxygen (O2) and temperature sensors and intensive sampling for biogeochemical processes. Emission factors (EF) ranged from 6.6 to 8.8 kg CH4–C/Mg wet food waste and were driven primarily by low redox and watering events. Composting resulted in low N2O emissions (0.01 kg N2O–N/Mg wet food waste). The overall EF value (CH4 + N2O) for food waste composting was 926 kgCO2e/Mg of dry food waste. Composting emissions were 38–84% lower than equivalent landfilling fluxes with a potential net minimum savings of 1.4 MMT CO2e for California by year 2025. Our results suggest that food waste composting can help mitigate emissions. Increased turning during the thermophilic phase and less watering overall could potentially further lower emissions.

Impacts of Global Climate Change on Agricultural Production: A Comprehensive Review

“…Globally, food waste is a pervasive and serious problem. It is estimated that approximately one-third of food produced globally is wasted annually, leading to greenhouse gas emissions [74,75]. This wasted food encompasses losses occurring at various stages including production, harvesting, processing, transportation, storage, and consumption.…”

Analisis Timbulan Sampah dan Pemanfaatan Sampah Organik Berbasis Eco enzyme Pada Kawasan Wisata Kuliner Air Salobar, Kota Ambon

“…Beberapa penelitian menunjukan penguraian sampah organik menghasilkan gas metana yang merupakan salah satu gas rumah kaca penyumbang efek pemanasan global (Puger, 2018). Berdasarkan teori ini maka keberadaan sampah organik berkontribusi besar terhadap perubahan iklim dunia (Pérez et al, 2023).…”

Effects of Additives on Greenhouse Gas Emission during Organic Waste Composting

“…퇴비화 과정은 온도를 기준으로 총 네 가지 단계로 구분된 다: 초기(mesophilic, 25-40°C), 고온(thermophilic, 40-65°C), 냉각(cooling, 25-40°C), 숙성(maturation, 20-25°C) [5]. 초기 단계에서는 미생물이 활성화되고 유기물이 분해되면서 CO 2 발생 및 온도가 상승하게 되고, 지속적인 산소 소모와 온도상 승으로 인한 고온 상태가 되면 혐기조건이 형성되어 CH 4 발 생이 일어난다 [5,6]. N 2 O는 암모니아화, 질산화, 탈질화 등 질소순환과 관련된 미생물 활동에 주로 영향을 받기 때문에, 40°C 이하로 유지되는 초기, 냉각 또는 숙성 단계에서 발생하 는 경향을 보인다 [6].…”