Remoção e recuperação de amônia de lixiviado de aterro sanitário utilizando membranas contactoras e comparação com processos convencionais

• Ano de defesa: 2014
• Autor(a) principal: Natalie Cristine Magalhaes
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Amônia; Air stripping; Lixiviado; Membranas contactoras; Membranas (Tecnologia); Meio ambiente; Engenharia sanitária
• Link de acesso: http://hdl.handle.net/1843/BUBD-AAHHDJ

Ammonia is one of the main pollutants that are released into natural receiving waters through improper discharge of domestic and agricultural wastewater. At the end of an effluent treatment is desirable to have a low ammonia concentration for two reasons: this substance is highly toxic to most species of fish and it may be oxidized by nitrifying microorganisms producing nitrites and nitrates that are undesirable to human beings. High concentrations of ammonia can be found in landfill leachate, whose inadequate disposal brings health, economic and esthetic problems, which makes its treatment necessary before your release into water bodies. In order to remove and recover ammonia present in landfill leachate and suit this effluent for disposal in relation to this component, the membrane contactor technology in liquid-liquid configuration can be used, since it offers a large surface area that facilitates rapid separation of ammonia present in the effluent, which subsequently react with a liquid absorbent, such as a sulfuric acid solution, for example, producing a byproduct: ammonium sulfate. In this context and seeking the recovery of ammonia in the form of ammonium sulfate, this study aimed to evaluate some operational parameters such as pH (10 and 12) and concentration of sulfuric acid solution (0.1 and 0.4 M), to obtain higher efficiency values for the removal and recovery of ammonia from the use of membrane contactors in comparison with the combined process of air stripping and absorption. In this study, with the pH around 10 and concentration of the sulfuric acid solution of 0.1 M, was obtained 99.9% and 87.0% of ammonia removal and recovery efficiency, respectively, using membrane contactors. The results obtained using the combined process, air stripping and absorption, were 62.9% and 52.7% of ammonia removal and recovery efficiency, respectively. A preliminary economic evaluation was conducted with all processes studied and the membrane contactor technology (with a wastewater pre-treatment by microfiltration), which gave a final cost of US$ 4.47/m3 of treated leachate, allowing the framework of the effluent to the standard required by legislation (20.0 mg.L-1 of NAT) and subsidizing the treatment of leachate due the production and sale of ammonium sulfate as fertilizer.