Tratamiento de aguas residuales provenientes de industria de productos de limpieza y desinfectantes por ozonización convencional y catalítica

Abstract

Wastewater produced during the production process of a cleaning and disinfectant industry located in the urban area of Uberlandia, state of Minas Gerais, Brasil, underwent an oxidative treatment process with O3/pH7, O3/pH3, O3/pH10, O3/pH3/Fe2+, O3/pH3/Fe3+, O3/pH3/Mn2+, O3/pH10/activated coal 1g/L e O3/pH10/activated coal 2g/L. The results were evaluated in terms of the removal percentage of two parameters: DQO and true color. The oxidative process utilizing homogeneous catalytic ozonation in the form of O3/pH3/Fe3+, was the most efficient both for residual water discoloration, as well as, for the organic matter oxidation. This maybe due to a better catalyst interaction with the chemical substances found in the matrix analyzed. Result supported by the current literature in this area, which states that the reacional mecanism of the ozonation process is yet not entirely stablished, but varies considerably with the type of metallic content employed and its interaction with the matrix compounds. The maximum DQO removal efficiency was 7,5% in 90 minutes of ozonation, possibly due to the production of ozonation sub_products. The maximum true color removal was 59% in 90 minutes of ozonation. Thus, the results indicate the importance of the contact time between bubbles of ascending ozone and residual water, in the ozonation process.