Aplicação da respirometria na determinação da composição da matéria orgânica em águas residuárias.

Abstract

To know the composition of the wastewater is extremely important information for the design, as well as for the operation of a treatment station. However, the composition and concentration of the wastewaters varies largely, being conveniently characterized by its biodegradability the form it is present in the wastewater: dissolved of particulate. Thus, four fractions can be distinguished: biodegradable soluble fraction (fbs), biodegradable particulate fraction (ftp), unbiodegradable soluble fraction (fts) and unbiodegradable particulate fraction (ftp). Each fraction tends a different behavior in a treatment system. The available methods to quantify these fractions are complex and demand a very long time. In this thesis an expedite method is presented for the determination of the composition of the organic matter of wastewaters using the respirometry, that is, the measure of oxygen uptake rate (OUR) along the time in a reactor. Through respirometry the biodegradable fractions are determined. The unbiodegradable soluble fraction is quantified by COD tests of the effluent and the influent. The unbiodegradable particulate fraction is obtained by a mass balance, subtracting from unity the sum of the other fractions.