Real⁃time emission characteristics of primary particulate from typical industrial activities

Industrial activities are the main sources of atmospheric particulate matter in China. To meet the needs of establishing emission inventory with high resolution，it is necessary to conduct some field measurements on the dynamic emission concentrations and emission factors of air pollutants from industrial sources. Based on a dilution sampling system，this study measured the particles emitted from five typical industrial activities including cement production，phar⁃ maceutical manufacturing， glass manufacturing， textile ( coal⁃fired boiler ) and steel sintering. The real⁃time emission mass concentrations of inhalable particulate matter (PM10)，fine particulate matter (PM2.5)，submicron par⁃ ticulate matter (PM1.0) and black carbon (BC) were obtained. Their emission factors were updated. The daily varia⁃ tions of PM1.0 / PM2.5 ，PM2.5 / PM10 and BC / PM2.5 ratios were analyzed. Results showed the average emission concentra⁃ tions of PM2.5 were (1.60±1.13)，(5.08±3.29)，(0.14±0.12)，(0.87±0.42) and (0.79±0.30) mg/ m3，respectively， and the average emission concentration of black carbon were (24.03±16.40)，(40.38±20.47)，(2.59±1.64)， (11.44±10.02) and (5.98±4.33) μg / m3 ，respectively. The emission concentrations of PM2.5 and BC exhibited obvi⁃ ous diurnal variation. Their high⁃values were 1.16-2.53 times and 1.57-2.40 times of corresponding low⁃values in a day，respectively. It may be due to the change of combustion conditions as the addition of fuels in different times and the fluctuation of efficiencies of air pollution control. The daily variations of primary particulate matter should be paid attention in establishing their emission inventory. The ratios of BC / PM2.5 for cement production industry and sin⁃ tering in steel industry are 7.5 times and 8.6 times of the recommended values of 0.002 and 0.001 in the techni⁃ cal manual for inventory establishment，respectively. The BC emission factors are 0.11 mg / kg and 0.02 mg / kg，respec⁃ tively，far lower than the 230 mg/kg and 2.52 mg/kg in the manual. If the BC emission factor recommended in the manual is used，its emission amounts will be overestimated. The BC / PM2.5 ratios of pharmaceutical，glass manu⁃ facturing，textile (coal⁃fired boiler) are (0.009 5±0.005 0)，(0.030 3±0.026 9) and (0.010 2±0.008 4)，respective⁃ ly. The BC emission factors are 0.43，0.29 and 0.68 mg/kg，respectively. The reference emission factors of BC are missing in the manual. The data in this study can provide a dataset for updating the inventory and the values in the technical manual.