Study On The Pollution Of PM _2.5 In Xi'an And Its Control Countermeasures

As the center cityof the northwest China, Xi’an has rapidly developed since the reform and opening up, which has gradually become China’s important economic, trade, industrial powerhouse.Fast developingurbanization and industrialization makegas pollution fromtransportation, industrial emissions and regional agriculturalbecome deteriorated.As a new type of environmental meteorological disaster, hazeweather occur frequently, which cause serious harm to people’s health and normal life in the city.As a result, the aerosol particles, especially in the physical and chemical properties, health effects, reduction of PM2.5means and emergency early warning has become an important scientific problems and people’s livelihood problems.This study summarized the domestic and foreign research status of PM2.5particles, illustrates the definition, classification and basic physical and chemical characteristics, formation mechanism of the air inhaled fine particles, especially for the source parsing techniques and various sampling analysis method has carried on the detailed comparative study on the classification, such as fine particulate matter for future research provides a more complete theory foundation in related field.Through the historical data collection, statistics, simulation analysis and other methods, Xi’an city are analysed and the guanzhong urban agglomeration of PM2.5pollution status quo, explore atmospheric aerosol physical and chemical characteristics and distribution of visibility, the influence of the human body health.To Xi’an haze weather atmospheric fine particulate matter during the period of time and space distribution, particle size distribution, diurnal variation, cycles are discussed. At the same time, put forward to adapt to the Xi’an special climate condition and emission reduction countermeasures, in an attempt to fundamentally eliminated by active or passive method serious fine particulate matter pollution.Withfocusingon the suddenhigh concentrations of haze, this study is based onthe environmental monitoring station and weather dataof Xi’an, including PM2.5and PM10mass concentration, the values of meteorological elements, ground weather data before and during the same periodtime. Analysis the emergence of Xi’an haze weather rules and influence factors, classification of haze weather typical weighting factors. Meanwhile, we proposed the new forecast early warning system, the test can be more than24hours in advance to complete the emergency warning, with high reliability and accuracy, which can be used as the government’s emergency early warning system to reduce emissions.