Primary air pollutant emissions and future prediction of iron and steel industry in China

Abstract

China is the largest iron and steel producing and consuming country in the world, which leads to enormous quantities of emitted air pollutants. Direct emissions of air pollutants from the iron and steel industry in China were estimated by developing a process and technology-based methodology using information of the proportion of pig iron, crude steel, and rolled steel produced from different processes and technology. Emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter (PM), volatile organic compound (VOCs), and dioxin (PCDD/Fs) were estimated for the year 2012, and future emissions of major pollutants (SO2, NOx, TSP) were projected up to 2030 based on technology developing trends and emission control policies. According to the estimation, 2222 kt of SO2, 937 kt of NOx, 1886 kt of TSP, 555 kt of PM2.5, 254 kt of VOCs, 618 g I-TEQ of PCDD/Fs was produced in China in 2012. Sintering produced 72.4% of SO2, 49.4% of NOx, 22.5% of TSP, 24.0% of PM2.5, 69.6% of VOCs and 98.0% of PCDD/Fs, which is the main emission source. Through faithful implementation of closing down outdated production and emission control policies, approximately 77%, 49%, 67% and 64% of SO2, NOx, TSP and PCDD/Fs emissions, respectively, could be further reduced in 2012. Emissions in 2020 and 2030 of iron and steel sectors were predicted applying scenario analysis. The removal potential for SO2 and TSP is larger than NOx by improvement of removal facilities, and southwest, northwest, and north China has the largest SO2, NOx, TSP and PCDD/Fs removal potential respectively.