| Such area sources as construction, catering, and other fields are the major sources of volatile organic compounds (VOCs). Because the area sources are usually distributed widely and irregularly, the estimation methods of VOCs emission from most area sources are mostly based on the emission factors. However, few work has been done to compare and verify the results with that gained based on real measurement. Taking the construction of a large entertainment project as research basis, theemission sources of VOCs in a large entertainment projects construction were identified, the major sources of VOCs including diesel exhaust, the off-road machinery, cooking fumes, coating were chosen for real-time measurement. After sampling by bags, the GC and GC/MS were utilized to determine emission concentration of NMHC and VOCs, respectively.The annual emission amount of VOCs from major sources was estimated, and the results based on measurement and based on emission factors were compared and the applicicable scopes were investigated.. It was showed that there was much diference between the results by two methods, the results based on real-time measurement was obviously lower than that based on emission factors. According to the above estimation, diesel exhuast was the main emission source of VOCs at construction steps and accounted for 93.55%. The fraction of VOCs emission from cooking fumes, coating, the off-road machinery based on testing data estimation was about 5.07%,0.94% and 0.44% as much as those estimation based on discharge coefficient.In this study, the specific VOCs species and concentration level from different sources were measured and the characteristics species were identified based on the consumption rate of OH and the maximum ozone generation potential. The results indicated that ethylene, propylene and butylene, toluene and acetylene are the key components of the diesel exhaust.Styrene, vinyl and toluene are the key components of the non-road machinery exhaust.Styrene, methyl methacrylate,4-methyl-2-pentanone, ethanol, acetone and other substance are the key components of coating process.The m,p-xylene, o-xylene,4-ethyl toluene, ethylbenzene, styrene,1,3,5 trimethylbenzene,1,2 4-trimethylbenzene are the key components of cooking fumes.Because the cookingemission is the major emission of VOCs during the process of construction and operation of a large amusement projects. Because few researches have been made for VOCs removal, the enhancing purification techniques of VOCs of cooking fumes was preliminarily studied. The The effectiveness of the microwave catalytic method was studied with Ag-cordierite as the catalyst. The optimal reaction conditions was found and the removal efficiency of hexane, toluene, xylene, ethanol andacetonewas compared. Results indicated that the removal efficiency of hexane, toluene, xylene, ethanol, and acetone were 65.7%,59.0%,56.7%,13.1% and 0%, respectively when the operation condition was controlled at 540 w of microwave and 0.1 mol/L concentration of catalyst.However, no purification efficiency of targeted air pollutants was found by UV technology. Microwave technology can be used toenhence the removal of VOCs from cooking fumes. |
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