Avaliação da demanda química de oxigênio no Lago da Perucaba, Arapiraca - AL

Abstract

The Perucaba lake, located in Arapiraca, has been suffering with a marked environmental degradation in the past decades caused by a fast urban population growth. since the lake did not fulfill its objective, which was the water supply, due to the salinity of the water. Therefore, the present work has as objective to evaluate the chemical oxygen demand, according to the legislation which regulates it. Analyzes were made in order to verify and evaluate this parameter, which measures the amount of organic matter susceptible to be oxidized by chemical means that exist in a liquid sample. It was observed an increase of the chemical demand of oxygen, caused by an interference of the climate, for the dry periods DQO had an average of 40mg / L, while in the rainy periods it presented a DQO average of 53.5 mg / L, thus the parameter analyzed was higher in the rainy season, as well the dispersion of the pollutant. Furthermore, comparisons were made with the resolution 357 from CONAMA, and it was identified that the water of Lake Perucaba are classified as Class IV fresh waters, which was unfit for human consumption.