Method Of Quickly Identifying The Types Of Particulate Pollution Based On Multi-parameter Feature Ratio And Its Application

In recent years,sulfur dioxide and nitrogen dioxide have been effectively controlled in China with the promulgation and effective implementation of air pollution prevention measures.However,the daily average concentration of particulate matter,mainly for fine particulate matter(PM_2.5),exceeded the standard significantly while the annual average concentration of particulate matter was in obvious downward trend,which causing serious impacts on human health and climate change.Identifying the types of particulate matter pollution is the basis process for revealing the pollution cause of the formation and conducting the dynamic source apportionment,for that fundamental cause of particulate matter are the emissions from pollution sources.But the current quantitative methods of identifying contamination types do not combine speed and accuracy,while the methods to classify receptor data are not effective enough to solve the problem of source resolution covariance.Therefore,this study proposed a method to identify the air pollution types based on the multi-parameter feature ratio method,identified the air pollution types at the city scale like Baotou and at the park scale like Loudi Lianyuan Iron and Steel Industrial Park;then,based on the results of pollution type identification,using the receptor model and backward trajectory model to investigate the sources and quantify source contributions of PM_2.5 from different directions to the ambient for different pollution types;finally,using the health risk assessment model to calculate the impact of different pollution sources on human health.The main conclusions are as follows:（1）Four particulate pollution types including sand dust,fugitive dust,second generation and accumulation,and other type were confirmed based on the air pollution characteristics and quality monitoring data(SO₂,NO₂,PM₁₀,PM_2.5 and CO)of Baotou by using the multi-parameter characteristic ratio.The sand dust type mostly occurred in the spring and autumn season with higher wind speed（5.6m/s）,higher boundary layer height（1016m）and lower relative humidity（36%）;fugitive dust type mostly occurred in the spring and winter season with high wind speed（4.7m/s）,high boundary layer height（641m）and low relative humidity（42%）;secondary generation and accumulation type mainly occurred in heating period during the autumn and winter with low wind speed（2.3m/s）,low mean boundary layer height（281 m）and high relative humidity（63%）.（2）Seven particulate pollution types including natural dust,industrial dust,secondary aerosol,coal combustion,iron and steel,road dust and mixed type were confirmed in the industrial park.The higher concentration components were mainly contributing from crustal sources in the natural dust type,and were mainly contributing from iron and steel industry,combustion and road sources in the industrial dust type,and were mainly contributing from the secondary transformation of gaseous pollutants in the secondary generation type,and were mainly contributing from combustion and steel industry emissions in the coal combustion type,and were mainly contributing from the iron and steel industry,combustion and road sources in the steel type,and were mainly contributing from road,coal combustion and motor vehicle exhaust emissions in the road dust type.（3）The results of PMF based on conventional pollutants showed that process sources and fossil fuel combustion sources were the main contributors to the second generation and accumulation type in Baotou.The dust and sand sources for the northwest path were the most significant sources of dust sand type.The dust sources and road mobile sources for northwest path were the most dominant sources of fugitive dust type.（4）The results of CMB based on component datas showed that the contribution of secondary sources including secondary nitrate and sulphate was the biggest for each type in the Lianyuan Iron and Steel Industrial Park.And without considering the contribution of secondary sources,the largest contributor was soil dust sources in the natural dust type,and were ironmaking and sintering in the industrial dust type,and were sintering and coal combustion dust in the coal combustion type,and was ironmaking in the iron and steel type,and was diesel vehicle exhaust in the road dust type.Also there were large differences in the source contributions of different incoming air masses for each type.The sources that contributed most to the PM_2.5 were soil dust sources in the northeast of the natural dust type（12.17%）,sintering in the northeast of the industrial dust type（24.00%）,secondary nitrate in the northeast of the secondary generation type（26.26%）,coal combustion dust in the northwest of the coal combustion type（9.53%）,the ironmaking in the south of the iron and steel type（9.66%）,and the diesel vehicle exhaust in the northeast of the road dust type（16.49%）.（5）Based on the health risk assessment model to quantify the health risk of each pollution type for different populations and sources contributing to PM_2.5in the Lianyuan Iron and Steel Industrial Park.The results showed that all pollution types had high carcinogenic and non-carcinogenic risks for all populations,with the highest carcinogenic risk for adult males,the lowest for children while all populations had the same non-carcinogenic risk.The health risk contribution to different sources were as follows:steelmaking made the greatest carcinogenic risk contribution and sintering generating CPM contributed the most to the non-carcinogenic risk to natural dust types;steelmaking had the greatest health risk contribution for industrial dust type and coal combustion type,while coal combustion dust contributed the most to the non-carcinogenic risk;secondary generation type has the highest carcinogenic risk contribution from sintering generating CPM and the non-carcinogenic risk contribution from coal combustion dust;ironmaking had the greatest health risk contribution for iron and steel type;sintering generating CPM had the greatest cancer risk contribution for road dust sources and road dust contributed the most to the non-carcinogenic risk.