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Receptor Modeling for Volatile Organic Compounds

1991; Elsevier BV; Linguagem: Inglês

10.1016/s0922-3487(08)70130-8

2212-1250

Peter A. Scheff, Richard A. Wadden,

Advanced Chemical Sensor Technologies

The Chemical Mass Balance (CMB) source reconciliation model has been found to be a useful tool for the evaluation of ambient speciated volatile organic compound (VOC) concentration data. The modes of generation of VOC's are also significantly different from sources of particulate matter. While the elemental signatures of particulate matter sources are directly related to raw material composition, the composition of VOC sources is based on the physical and chemical processes that consume or modify the raw material. As with elemental source compositions, collinearities between specific VOC categories cause statistical problems and limit source resolution by the CMB method. Experience to date suggests that the sources examined fall into three major groups with respect to collinearity: (1) vehicles, gas vapor and refineries, (2) solvent and coating sources including architectural coatings, printing inks, and auto painting, and (3) sources of chlorinated organic including vapor degreasing, dry-cleaning and wastewater treatment. The reactivity of the organic tracer fitting compounds may also affect the model. One underlying assumption of the CMB receptor model is the conservation of mass of the tracer species relative to the total emission. While this is not completely true for any categorical pollutant, the conservation assumption poses special problems when the tracers are all reactive hydrocarbons. This problem, along with discussions of emission inventory, validation, modeling un-identified sources and the use of extended fingerprints are all examined in this chapter.