Emission accounting, sectoral contributions and gridded spatial distribution of greenhouse gases in a typical petrochemical district of Shanghai

In this study, a petrochemical industrial district (PID) in the megacity of Shanghai was selected as a case study to investigate the quantity and components, sectoral contributions, and spatial distribution of greenhouse gas (GHG) emissions, including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). The total GHG emissions from the PID were 25.86 million tonnes of carbon dioxide equivalent (CO2eq), of which CO2 made the largest contribution (96.9%), followed by N2O (2%) and CH4 (1.1%). In terms of the sectoral contributions, energy use and industrial processes and product use (IPPU) were the two major emission sources of GHGs, accounting for 76.14% and 23.17% of the total, respectively. Moreover, GHG emissions from energy use and IPPU in the petrochemical industry accounted for 36.1% of the total, indicating the significance of the petrochemical industry for GHG emissions. A high-resolution gridded (200 × 200 m) spatial distribution map of GHG emissions was created based on point source, line source, and area source databases, showing a clear difference in the emission levels of GHGs among the grids. Thirteen ultra-high grids with GHG emissions above 10,000 tonnes CO2eq, accounted for more than 90% of the total emissions in the PID, which should be given more attention in emission management programs. The results provided useful insights into the amount and composition, sectoral contributions, and gridded spatial distribution characteristics of GHG emissions in the petrochemical industry, and can be used by decision makers to develop refined management strategies for GHG emission reductions in typical petrochemical districts.