Aplicabilidade da eletrocoagulação, eletrocoagulação seguida de reativo de fenton e eletrofenton no tratamento de lixiviado de aterro sanitário

• Autor(a) principal: Lima, Claudia Maria Russo de
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/4655
• topic: Sanitary landfill leachate; Electrolytic process; Electrocoagulation; Líquido percolado; Fenton; Eletro-Fenton; Tratamento de efluentes; Processo eletrolítico; Eletrocoagulaçao; Química; Águas residuais; Águas residuais - Purificação - Processo eletrolítico; 54

This work aimed to study processes of electrochemical treatment applied in a sanitary landfill leachate, with the investigation of physical and chemical parameters of interest and its better operation conditions. The following systems were studied: electrocoagulation, electrocoagulation followed by the Fenton ´s reagent and eletroFenton. Leachates from the landfill in the municipality of Aracruz (Espírito Santo) were used in the research, collected in 2008 and 2009. The samples were sent to the Laboratory of Analytical Chemistry, Federal University of Espirito Santo, and preserved in refrigerator. An electrochemical reactor was constructed using a 3L beaker, mechanical agitation, and electrodes of carbon steel 1020 plates, coupled to a 9 A source of constant direct current. Several experiments were performed for studies of electrocoagulation in order to determine the best operation, with changes in the structural parameters (electrode geometry) and operational (temperature, electrolyte volume and polarity reversal). For the tests of electrocoagulation followed by Fenton ´s reagent, it has changed the relationship between the quantities of ferrous sulfate heptahydrate and hydrogen peroxide, using the ratio of 1:17 and 1:25 of the salt with hydrogen peroxide. For eletroFenton tests were also conducted tests on the change in relationship, but in amounts of 1:20 and 1:25. As result of this research, it was observed that the electrolytic process and this in combination with advanced oxidation process are indicated for the treatment of landfill leachate generated from municipal solid waste. The initial characterization of leachate (pH, organic matter, ammonia nitrogen, chloride and metals) indicated that it comes from landfill over the age of 2 years with a degree of stabilization of the landfill in the acidogenic phase. The electrocoagulation, electrocoagulation followed by Fenton's reagent and eletroFenton shown to be adequate for the process of removing color, turbidity, organic compounds and metals, but not suitable for removal of ammonia and particulate matter. Better results were obtained by combining the electrolytic process with the oxidative, and the treatment eletroFenton showed better results in general, combined with a treatment period shorter (30 minutes). We obtained a removal efficiency of COD between 40 and 50% in electrocoagulation, 60 to 70% in electrocoagulation followed by Fenton, and up to 78% in eletroFenton system. The results of this study are of great importance as support for project development of physical-chemical treatments on an industrial scale for the treatment of leachate from landfill