VOC EMISSIONS FROM DUSTY AIR FILTERS

摘要

Emissions from dust collected on pre- and main ventilation filters were examined by using thermodesorption technique (TCT-GC-MS). The elemental composition of the dust samples was determined with a CHN elemental and a thermal-optical carbon analyzer. Desorption experiments were made at 70℃ and 150℃. Aromatic hydrocarbons were the main emission products at 70℃. Some emissions of aldehydes were also detected. At 150℃, main emitted compounds included carboxylic acids, alcohols, aldehydes, terpenes, phthalates, and aromatic hydrocarbons. Filter samples were collected in late winter, and, therefore contained a lot of fresh particles derived from traffic, combustion, and power production. In earlier studies, the intensity of odors from filters was found to be strongest in the winter. Thus, aromatic compounds may contribute to the odor formation. Contents of carbon and elemental nitrogen were 7-40% and 1-2%, respectively. The carbon content was highest in the dust, which was collected from a pre-filter.