AN APPROXIMATE MODEL WITH CHEMICAL REACTION FOR A THERMOELECTRIC PLANT GAS RELEASED

Edson Abel dos Santos Chiaramonte¹; Belkis Chalup Silveira Roesler¹; Jorge Rodolfo Silva Zabadal²

¹ UNIPAMPA; ² UFRGS

doi:10.20906/CPS/COB-2015-1711

Resumo

In recent decades, the dispersion of chemical compounds in the atmosphere mainly from human activities has drawn much attention. These gases are responsible for phenomena such as acid rain, "smog" and photochemical formation of particulate materials. These gases are emitted by industrial sources, automobile traffic and anthropogenic urban and rural. The use of energy derived from power plants is a much used and one of the most used fuel is coal. The environmental control agencies and society has drawn attention to their propagation in the atmosphere and the control of its emissions. Because of that, there is a research of the "Environmental Protection Agency (EPA)" of the United States, where several types of emissions from known sources are compiled, sorted and values of emission factors are presented to estimate the release rates of this gases. This is called "AP-42" - Compilation of Emission Factors of Air Pollutants. This work has developed a computer program that estimates emission rates of the main compounds released by a power plant from coal combustion and evaluates them propagation in the atmosphere. Some of these compounds are those that participate in chemical oxidation of organic chemistry and the formation of acid gases in the atmosphere. In the first part of the software, are estimated concentration of the gases emitted in the chimney from the coal composition, the air composition and AP-42 emission factors. The second part of the program is performed propagation, dispersion and chemical reactions in the atmosphere. It was used a simplified chemical mechanism that make an uncoupling of the gases nitrogen chemistry (NOx) and the volatile organic compounds chemistry (VOC). Numerical results are presented for concentrations of gases Nitric Acid (HNO3), Nitrogen Dioxide (NO2), nitrous oxide (NO) and ozone (O3) generated from the emission source downwind.

Palavras-chave: gas dispersion; emission; reactin