Effects of space heating on the pollutant emission intensities in “2+26” cities

The PM2.5 concentration of the air pollution transmission channel cities (APTCC) of the Beijing-Tianjin-Hebei area (“2 + 26” cities) is significantly higher in the heating season than in the non-heating season. Space heating in northern China involves substantial fossil fuel combustion that produces haze-generating pollutants. In order to improve the atmospheric environment, it is necessary to quantitatively analyze the pollutants generated by such heating. In this study, the emission factors of several common heat sources, such as combined heat and power (CHP), boilers, rural biomass stoves, and scattered coal-heating are analyzed and classified into direct emissions and indirect emissions. Direct emissions refer to all emissions generated locally by the heat source due to fuel combustion, whereas indirect emissions are those generated elsewhere by the heat source due to electricity consumption. The “2 + 26” cities are then divided into six small urban agglomerations by cluster analysis, and the heat supply of various heat sources are investigated. Finally, the pollutant emission intensity due to heating is calculated per unit land area for each small urban agglomeration in 2016. This study shows that the emission intensity of pollutants generated by urban heating in Beijing and Tianjin is higher than that in other agglomerations, whereas the pollution generated by rural heating is higher than that generated by urban heating in many urban agglomerations. Finally, this study proposes suggestions for clean heating in northern China in order to reduce pollutant emissions.