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Environmental Engineering and Management Journal November/December <strong>2007</strong>, Vol.6, No.6, 529-535 http://omicron.ch.tuiasi.ro/<strong>EEMJ</strong>/ “Gh. Asachi” Technical University of Iasi, Romania ______________________________________________________________________________________________ ENVIRONMENTAL POLLUTION WITH VOCs AND POSSIBILITIES FOR EMISSION TREATMENT Liliana Lazăr ∗ , Ion Balasanian, Florin Bandrabur “Gh. Asachi” Technical University of Iasi, Faculty of Chemical Engineering, Department of Engineering Inorganic Substances, 71A D.Mangeron Bd., 700050 - Iasi, Romania Abstract Volatile organic compounds (VOCs) constitutes an important class of environmental pollutants, which, together with other contaminants as NO x , SO x , CO, NH 3 , CO 2 etc. participate in degradation of atmosphere and exhibit a potential risk for human health. VOC emissions may be generated in more than 25 percentages through the use of solvents in different industrial or house holding activities. For applying a certain plan concerning the pollution reduction, any user of organic solvents containing VOCs should accomplish a proper management of these ones, such as the concentrations of the pollutants to frame within the limits regulated by the European legislation. The pollutant emission containing VOCs may be subjected to a treatment process, established concordant to their characteristics and provenience, as well as to the possibility and the cost of implementation in the technological process. In this paper, a scheme for trapping and treatment of the gas emissions resulted from the activities related to degreasing in organic solvents containing VOCs is presented. Key words: VOC, environmental pollution, solvents, emissions, catalytic incineration 1. Introduction The volatile organic compounds are considered to be organic substances, excluding methane, which contain carbon and hydrogen, total or partial substituted by other atoms, which exhibit a vapour pressure higher or equal to 0.01 kPa at 20 0 C and which may be found in gas or vapour state in the operation conditions carried-out in units (EC Directive, 1999). Due to their specific characteristics (high volatility, harmful, toxic or carcinogenic effect), the VOC pollutants show a potential risk for human health, even at low concentrations in gas emissions. In consequence, the VOC pollution reduction and control became a major problem at the international level in the last decades. The basic objectives of the environmental policies consist in ensuring the protection and conservation of the nature, as well as durable use of its components in accordance to regulations regarding the integrated pollution prevention and control foreseen by the IPPC Directive (EC Directive, 1996). The VOC environmental impact consists in direct effects, as a result of their specific characteristics, as well as in indirect effects that owe to their participation in reactions occurring in the presence of atmosphere constituents and solar light. In these reactions, active radicals that disturb the normal cycle of nitrogen in atmosphere may form. VOC pollutants are able to participate in depletion of the ozone layer, in enhancement of the greenhouse effect, in appearance of the photochemical smog (Dumitriu and Hulea, 1999). The effects of VOCs on the human body depend on their chemical nature, concentration in air and duration of their action. Most frequently, the action of these pollutants occurs at low concentration resulting in a chronic or a long–term effects that need long period to lead to changes in the human health. Very high concentrations yield to acute or immediate effects, cases when the body reactions appear fast. The VOCs may action not only upon the exposed ∗ Author to whom all correspondence should be addressed: lillazar@ch.tuiasi.ro