Avaliação da eficiência de um sistema de flotação por ar dissolvido para tratamento de águas residuárias de uma refinaria de petróleo

Abstract

Rivers and lakes contamination with hydrocarbons is a growing concern in contemporary society, either by the impact on ecosystems as degradation of water quality. The main sources are leaks during the carriage of petroleum and derivatives and wastewater from refineries andpetrochemicals. In these industries the wastewater physical-chemical treatment to broke emulsions and remove oil and greases is essential to achieve more and more restrictive standards for effluent discharges as well as water reuse. The dissolved-air flotation (DAF) is currently one of the most common processes applied, reaching contaminants removalefficiency above 90%. However the operating conditions of a flotation system are essential to achieve these results. In this work was available the flotation system applied for oil wastewater in a petroleum refinery. There was a low efficiency in reducing the content of oil and greases and total suspended solids, mainly related to the runaway of drive parameters. Options were proposed for improvement of the unit control, especially through small interventions in the operation.