Climate Change Impact of the Development in Household Waste Management in China
Yan Zhao, Huimin Chang, Xiao Liu, Valentina Bisinella, Thomas H. Christensen
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.