Climate Change Impact of the Development in Household Waste Management in China

Abstract

The potential climate change impacts of the development in Chinese household waste management, with less landfilling, more incineration with energy recovery, and source-separated food waste treated in biorefineries, were assessed through a life cycle assessment. When the waste management system interacts with a fossil-based energy system, landfilling produces a load of 144 kg CO2-eq/ton wet waste, while incineration shows a saving of 36 kg CO2-eq/ton wet waste. The introduction of food waste source separation lowers climate change impacts by an additional 33 kg CO2-eq/ton at a 60% sorting efficiency. As the Chinese energy system lowers its climate change impact over the next 30 years, energy recovery from waste treatment will change its relative contribution to climate change. In nonfossil energy systems, landfilling is estimated to have a climate change load of 180–240 kg CO2-eq/ton wet waste, while incineration, including combinations with the source-separation of food waste, will have a load of 310–540 kg CO2-eq/ton wet waste. These large intervals are due to waste composition uncertainty. However, considering a 20 year CH4 characterization factor representing a shorter time perspective, the impacts from landfilling are more dramatic due to the large methane release. This significant climate change impact calls for an increased focus on the developments in Chinese household waste management. The key issues identified may also apply to other countries.

Decarbonizing Food Waste Treatment through Anaerobic Codigestion with Yard Waste: Energy, Engineering, Economic, and Environmental Aspects

“…The calculated carbon footprint of Scenario B was about 68 kg CO 2 -eq/t-FW compared to Scenario A (BAU) with 214 kg CO 2 -eq/t-FW for source-separated FW. In a recent study, authors found the source-segregated FW can lower climate change impacts by 33 kg CO 2 -eq/t-FW at a 60% source efficiency. A decentralized AcD system (Scenario B) could decrease carbon emissions by ∼32,000 kg of CO 2 -eq per year (with a transportation distance of 10 km), and a decentralized AcD system inside the campus (see Pathway 1 (P1), assuming AcD without transportation) would further reduce carbon emissions by ∼631 kg of CO 2 -eq per year, compared to the composting system (BAU).…”

Machine Learning-Based Prediction of the CO2 Concentration in the Flue Gas and Carbon Emissions from a Waste Incineration Plant

“…In previous research, the assessment of direct carbon emissions stemming from waste incineration predominantly relied on the physical composition of the incinerated waste. , However, the physical composition of waste entails significant labor efforts, and most of the studies have a low frequency of physical composition investigation and often use data from previous years or from specific studies conducted within the same year, which may not accurately reflect the current situation. , It is worth noting that the physical composition of waste can vary substantially due to changes in waste management policies and seasonal fluctuations . Consequently, relying on outdated waste composition data can lead to delayed accounting results that do not effectively represent the current levels of direct carbon emissions from waste incineration facilities.…”

Climate Change Impact of Diverse Food Waste Valorization Processes beyond Anaerobic Digestion

“…5 Meanwhile, the GWP of incineration will increase significantly if waste management interacts with a non-fossil-based energy system. 6 As to biological technologies including composting and AD, land application of compost and digestate is important for their high greenhouse reduction potential; 4,7 unfortunately, it is the most challenging in practice. The market acceptance of compost products derived from FW is limited due to the concern about the potential secondary pollutants during land use.…”

“…The high moisture content and low calorific value of FW are not conducive to the stable operation of incineration, and the chloride salt contained is one of the possible precursors of dioxins . Meanwhile, the GWP of incineration will increase significantly if waste management interacts with a non-fossil-based energy system . As to biological technologies including composting and AD, land application of compost and digestate is important for their high greenhouse reduction potential; , unfortunately, it is the most challenging in practice.…”