Evaluación de contaminantes atmosféricos provenientes del sector automotriz en la avenida 9 de Octubre de la ciudad de Riobamba.

Abstract

In the current investigation, the atmospheric pollutants coming from the vehicles that pass through the sector of the intersection of the avenues 9 of October and Juan Félix Proaño of Riobamba city, characterized by its high vehicular traffic. In the first instance, were evaluated to the determination of 22 monitoring points in the mentioned area, chosen for technical criteria, where the presence of NOx (nitrogen oxides) was measured by passive sampling using triethanolamine, n-butanol and distilled water collection tubes. The study was carried out during the months of January, February, and March of 2019. The samples taken were analyzed weekly with the help of a UV spectrophotometer and the absorbance values were read prior to the construction of a calibration curve to be able to determine the NOx concentration by means of a series of formulas. Later, maps were elaborated to visualize the zones of greater NOx concentration, then statistical analyses were carried out to establish the factors that influence the variation of NOx concentration. It was determined that they are related to the number of vehicles that circulate in the area of study, environmental temperature, relative humidity, and soil temperature. It was also found that the NOx emissions do not exceed the permissible limits established by the “Ministerio de Ambiente” (150 ug/ m3 in 24 hours), since the daily emissions reach a maximum of 24.39 ug / m3, however, to obtain better results in the later, the study could be carried out in a wider area and with longer monitoring time.