City-level Assessment For Resource Potential And Greenhouse Gas Emissions Of Municipal Solid Waste In China

Cities are engines for tackling climate change and achieving sustainable development.Because of the ever-increasing municipal solid waste（MSW）generation and the relatively lagging waste disposal capacity,Chinese cities are facing the dual pressure of garbage siege and climate change.The accurate assessment of the resource potential and greenhouse gas（GHG）emissions of MSW has become a prerequisite for making urban low-carbon and energy policies.However,the existing studies on China’s resource potential and GHG emissions of MSW based on relatively low resolution and poor timeliness,which reduce the accuracy of the results.Additionally,the drivers of GHG emissions changes from MSW remains unclear.The knowledge gap restricts policy-makers to reasonably formulate waste management and mitigation policies.This study estimates the resource potential and GHG emissions of MSW for 295 Chinese prefecture-level cities,based on the data of MSW clearance and disposal during the period2006-2017.This study first analyses the city-level spatial distribution of MSW generation based on the geographic information system.Given the physical characteristics of MSW and key parameters of MSW treatment pathways,city-level resource potential and power generation potential of MSW are then evaluated.Furthermore,using the GHG inventory guidelines,this study calculates methane（CH₄）,carbon dioxide（CO₂）and nitrous oxide（N₂O）emissions from MSW landfill,incineration and compost for 295 cities during the accounting period.Finally,this study builds the logarithmic mean divisia index（LMDI）model to identify the driving factors of the change in GHG emissions of MSW.Results show that the resource potential of MSW in China increased from 737.05 PJ in2006 to 1071.97 PJ in 2017.If the MSW landfill and incineration could be used for power generation,14.05 TWh～57.81 TWh of electricity would be generated,which accounted for0.49%～0.87%of total power production.Spatially,the MSW resource potential evolved from“north dense and south sparse”to“east dense and west sparse”,and the power generation potential of MSW decreased from east to west.MSW resource potential of 76.98%of Chinese prefecture-level cities had increased from 2006 to 2017.The average annual growth rate（AAGR）of MSW resource potential in Baoshan,Putian,Zhangzhou,Changsha,Ganzhou,Heze,Haikou,Nanning,Huizhou and Fuzhou took the top 10 positions.The results of GHG emissions accounting of MSW show that China’s domestic GHG emissions of MSW increased from 39.34 Mt CO₂e in 2006 to 109.79 Mt CO₂e in 2017,which accounted for 0.64%～1.13%of total CO₂ emissions.GHG emissions of MSW in 91.67%of prefecture-level cities showed an increasing trend.The AAGR of GHG emissions from MSW in Fuzhou,Jieyang,Neijiang,Kunming,Wuhan,Yuncheng,Shuozhou,Lanzhou,Huizhou and Baoshan held the top 10positions.In 2017,the GHG emissions of MSW of large cities contributed 52.86%of the national emissions.The GHG emissions of MSW in 19 first-tier and new first-tier cities accounted for 36.61%of the total.The average emissions of service-based cities were higher than those of industrial cities.The results of the decomposition analysis show that per capita economic output had contributed 65.09%to the growth of GHG emissions of MSW,and per GDP intensity of waste disposal had an inhibitory effect on the emissions.Based on the major results,this study recommends that developed cities（such as Beijing,Shanghai and Shenzhen）increase investment and financing incentives for the local MSW industry,and innovate waste treatment technologies to strengthen environmental governance.It is also suggested to further optimize the waste treatment structure and promote the construction of waste incineration projects in western cities such as Lanzhou.Overall,this study quantifies the resource potential of MSW and complies time series inventory GHG emissions of MSW with the city-level resolution in China.The results can provide valuable guidance on the bottom-up MSW sustainable management policies.