Analysis on Current Situation and Causes of Ozone Pollution in Meishan
In order to understand the characteristics and causes of ozone pollution in Meishan in recent years,based on the automatic ozone monitoring data of 2016 to 2021 and in combination with results of the second national survey of pollution sources in Meishan,automatic monitoring data of volatile organic compounds(VOCs),data analysis on VOCs pollution source etc.,the current situation of local ozone pollution,source of precursors,ozone formation potential(OFP)and sensitivity of ozone were analyzed.The results indicated:(1)the ozone concentration,the out-of-standard days,and pollution load showed a rising trend in general,the first occurrence of ozone pollution in each year was advanced,but the last occurrence was delayed;(2)NOx in ozone precursors were mainly from mobile sources and industrial sources,while VOCs were mainly from domestic pollutions,mobile sources,and industrial sources;(3)the average component concentration of VOCs was alkanes>olefin>aromatics,and OFP was olefin>aromatics>alkanes;(4)from a single component point of view,the ethylene and m/P-xylene had both high OFP and great control and emission reduction potentials,which were the key species in ozone pollution control;and(5)according to the ozone sensitivity analysis results,Meishan was a typical VOCs control area,and the ozone control strategy should be to increase the emission reduction of VOCs,or reduce VOCs and NOx both,with the emission reduction ratio of about 4.5∶1,and the higher the emission reduction ratio,the more conducive to the rapid decline of O3.Through the preliminary study on the status quo and causes of ozone pollution,the paper provides a reference for the scientific prevention and control of local ozone pollution,and indicates the key direction of ozone control in the future.