Tratamento eletroquímico de esgotos sanitários

Abstract

Basic sanitation is a public service with the most deficiency in infrastructure in Brazil, in particular the service of collection and treatment of sewage followed by collection services and waste treatment. The scenary of sanitation in Brazil, especially in the big cities, it becomes increasingly costly and challenging because the population is increasingly concentrated in urban areas. In this regard, it is necessary to adopt minimization and water conservation programs, and the implementation of decentralized treatment systems such as compact units which require a smaller area and offer similar performance. Another concern in the area of sanitation is about the removal efficiency of compounds present in small concentrations in sewage treatment plants as medicines for human and veterinary use, as well as beauty and personal care products. This study aimed to evaluate the efficiency of the electrochemical process (electrocoagulation and electro-oxidation) with three different electrodes (aluminum, iron and graphite) for COD removal in sewage and estimate the energy consumption. Evaluate the electro-oxidation in sewage for the degradation of two drugs (diclofenac and clofibric acid). The aluminum electrodes were more efficient for COD removal and achieved efficiency up to 80% for most of the tests performed. Iron electrodes achieved similar result, but it gives residual color in the effluent. Aluminum electrodes save energy compare with iron and graphite electrodes. The electrochemical process is a promising technique for removal pharmaceutical compounds used in this research.