Study On Monitoring Of VOC And Its Transfer Conversion Rule In The Atmosphere

This thesis is concerned with determining methods of VOCs in atmosphere .Determine the VOCs use method of Sorbent absorb—Solution desorb—GC/MS. Mainly compare of some kind of sorbent,including there absorb and desorb ability,choose the best sorbent.Compare of organic solvent including CS2, CHCl3, CH2Cl2, determine the most suitable solvent. The rule of transfer conversion for VOCs has been researched, especially the effects of temperature, weather, velocity of windy and seasons.The results from experiments show that the best sorbent is active carbon fiber, the optimal solution is CS2, and the best conditions for analysis with apparatus include the initial temperature 30, remaining 5 minutes, heating up to 50 at the rate of 10, then keeping 1 minutes and up to 200 with rate of 50. The properties from experiments have been listed as follows: the relation between each standard curve is good; the linear correlation is above 0.999; the rate of recycle is from 90~110% and the standard deviation for attentive experiments is below 7.1%, desorption ratio are under 89%.The concentraction of VOCs in ShengHua is higher than in main street,and the main source for VOCs of main streets is tail gas from cars with higher ratio of arene.The effects of each factor on the transfer conversion of VOCs include that higher velocity of windy is good for transferring of VOCs; the sunny day is better than the rainy day for the actinochemistry reaction; the VOCs changes into O3 and the effect of temperature on transfer conversion is not great. The actinochemistry reaction in the atmosphere of Shenghua refinery plant is stronger than main streets.