Remediação de áreas contaminadas por BTEX em postos revendedores de combustíveis utilizando processo oxidativo avançado do tipo Fenton

• Ano de defesa: 2015
• Autor(a) principal: Medina, Melissa Cunha
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Positivo; Brasil; Pós-Graduação; Programa de Pós-Graduação em Gestão Ambiental; UP
• Palavras-chave em Português: Biorremediação; Processo oxidativo avançado; Oxidação química in situ; CNPQ::CIENCIAS BIOLOGICAS; CNPQ::ENGENHARIAS::ENGENHARIA SANITARIA
• Link de acesso: https://repositorio.cruzeirodosul.edu.br/handle/123456789/2461

Benzene, Toluene, Ethylbenzene and Xylene (BTEX) are aromatic hydrocarbons present in gasoline. Toxic, recalcitrant and non-biodegradable, these compounds are responsible for the severity of the contamination by gasoline in the environment. Problems arising from such contamination can be mitigated through remediation strategies, which involve physical, chemical and/or biological processes. This study was focused on in situ remediation approaches of groundwater contaminated by BTEX involving the Fenton Advanced Oxidation Process (AOP). The overall aim of the study has been to support refined planning approaches of this type of intervention when using three injection methods, namely Direct Push, Pressurised Well and Gravity Well injections. The specific objectives have been to characterise and understand results obtained for the remediation efficiency (RE) in four areas, so as to infer on the relative importance of field conditions and operational parameters in determining the RE. This required an assessment of the contaminated area and contaminant mass for remediation stages pre, during and post intervention. Values of RE-mass of the order of 99% were obtained for Benzene by Direct Push and Gravity Well injections (with area-based minima of 68% and 8,3% respectively), and 55% with the Pressurised Well injection (with an area-based minimum of 23%). The results obtained for Benzene were subjected to further scrutiny through correlation and multiple regression analyses, which gave mathematical functions to describe the combined effect of the control variables on the RE. The relative contribution of each variable was then estimated. It was found, in agreement with the international literature, that the pH had a key role in the degradation process by AOP Fenton, for the whole range of conditions assessed. Another important realisation was that, more important than the choice of injection method used, is to plan the operational conditions of a remediation intervention – such as the density of injection points and volume of solution per impacted unit area – considering the characteristics of the contaminated site and contaminant identified in preliminary diagnostic assessments.