Nitrogen flow characteristics of solid waste in China.

Area of Science:

• Environmental Science
• Waste Management
• Ecology

Background:

• Rapid socio-economic development has led to a surge in solid waste (SW), posing significant public health and environmental challenges.
• The fate of nitrogen in solid waste (SWN) is critical, as different treatment methods have varying environmental impacts.
• A comprehensive evaluation of SWN sources, fate, and cascading effects is essential for effective management.

Purpose of the Study:

• To conduct a systematic evaluation of SWN flow, including generation, treatment, and emissions in China from 2008 to 2017.
• To identify the primary sources and pathways of SWN pollution.
• To provide a scientific basis for sustainable waste management policies.

Main Methods:

• A decade-long (2008-2017) quantitative analysis of SWN generation, treatment, and emission data in China.
• Assessment of nitrogen flow through different SW treatment methods, including landfill, incineration, and composting.
• Quantification of atmospheric and groundwater N pollution emissions.

Main Results:

• SWN flow and N pollution emissions from SW treatment increased by 19.7% and 27.6% respectively between 2008 and 2017.
• Domestic garbage was the largest contributor to SWN.
• Landfill accounted for 51.8% of total SWN, with landfill and incineration being major sources of N pollution emissions.

Conclusions:

• Urgent changes in waste treatment methods are needed in China, emphasizing classified domestic garbage management and resource recycling.
• Approximately 92.3% of N pollution emissions were released into the atmosphere (as NH3 and NOx), and 7.7% into groundwater.
• Targeted reduction strategies for NH3 (landfill, dumping, compost) and NOx (incineration) are crucial for mitigating environmental impact.