Beijing Haze detects dangerous organic compounds

The Chinese Academy of Sciences recently released the latest findings of the "Atmospheric Haze Control" special group, the research finds that the recent strong haze incident is the result of the abnormal weather situation caused by the atmospheric stability, anthropogenic pollution emissions, dust and rich water vapor, which is a natural and man-made factor together. Study on the haze incident of pollutant in the water vapor, it is believed that human pollutant emission is caused by haze weather, can be said to be "mastermind." Special group members, the Chinese Academy of Sciences Research Institute of Remote Sensing and digital Earth, said Chen Liangfu, the soluble elements of air pollutants encountered floating dust minerals will quickly package, forming a mixture of particles, and then encounter a larger air relative humidity, will soon occur moisture absorption growth, particle size growth of twice times to 3 times times, The extinction coefficient is increased by 8 times to 9 times times, which means that the visibility decreases to one-eighth to One-nineth. Generally speaking, the air of the original small particles of pollutants in the water after the water vapor into the human eye can be seen large particles, the occurrence of gray haze incident. According to the monitoring data of 15 PM2.5 stations distributed in the Beijing-Tianjin-Hebei area, the January Beijing-Tianjin-Hebei 5-strong haze pollution occurred from January 6 to 8th, 9th to 15th, 17th to 19th, 22nd to 23rd, 25th to 31st, respectively. These 5 times without Chen Liangfu said the water vapor to do "accomplice". The haze detected a dangerous organic compound. "The source of atmospheric haze," said Wang Yuesi, a researcher at the Institute of Atmospheric Physics at the Chinese Academy of Sciences. It is a mixture of smog events and smog events in Los Angeles in the 1952 in London and in the 40-50 's, and superimposed the Chinese-style dust aerosols. Especially noteworthy is the Los Angeles photochemical smog incident, in the pollution incident, a total of more than 800 people were killed. In a subsequent investigation, the U.S. government said that oil volatiles (hydrocarbons) and dioxide, under intense sun ultraviolet rays, produce an irritating organic compound called photochemical reaction, the product of which is poisonous photochemical smog. In a special study of the Beijing-Tianjin-Hebei Haze, the special group detected a large amount of organic particulate matter, which in Wang's view was "the most dangerous signal" because it was "one of the main components of photochemical smog in the last century in Los Angeles". Through source-resolution technology, these organic compounds, including nitrogen, have been identified with 4 types of organic materials: oxidized organic particulate matter, mainly from around Beijing, smoke-type organic matter, mainly from the local cooking source emissions, nitrogen enrichment of organic matter, a chemical product, as well as hydrocarbon organic particulate matter, Mainly from automobile exhaust and coal. The oxidation-type organic particles accounted for the largest proportion in the whole pollution process, 44%, the remaining three groups accounted for 21%, 17% and 18% respectively. It is suggested that the key control industry and the coal-fired special group attribute these factors to "the direct consequences of man-made extensive emissions and natural ecological destruction". In the Beijing area, the motor vehicle is the city PM2.5The largest source, about 1/4, followed by coal and foreign transport, each accounted for 1/5. For the whole Beijing-Tianjin-Hebei region, the special group believes that the focus should be on controlling industrial and coal-burning processes, focusing on desulfurization, denitrification and dust removal in the combustion process, and on diesel vehicle emissions and oil quality. In Wang's words, "controlling the haze still needs to start with controlling pollutant emissions." ”