Adição de biomassa microalgal ao processo eletrolítico por corrente direta pulsada para remoção de íons CU 2+ e NI2+ de efluentes gerados em indústrias de galvanoplastia

• Autor(a) principal: Maia, Liana Geisa Conrado
• Data de Publicação: 2021
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/59079
• topic: Processo eletrolítico; Biossorção; Chlorella vulgaris; Remoção de metais; Efluente de galvanoplastia

The present work was developed with the intention of solving the problem of waste disposal in a clad jewelry production industry, which can be summarized as a series of innovative technological strategies that minimize the emission of pollutants, as it creates alternatives for them to be properly treated according to the parameters required by local legislation. A bibliometric study from 1999 to 2019 of articles indexed on the Web of ScienceTM and SCOPUS showed the publication of only 43 articles, using search terms: “electrocoagulation”, and (and) “biosorption”. After an exploratory reading of the 10 articles most cited in the references, it was observed that only one article dealt with the treatment of effluents using a biosorbent together with the electrolytic process. The thematic use of microalgae in electrolytic processes for metal removal proved to be a little debated topic during this period. The application of the electrolytic process in order to treat the water from the washing of pieces of a jeweled jewelry industry, after application of the electroplating process, coupled with the bioremediation potential of the microalgae Chlorella vulgaris proved to be an innovative and promising topic for study. A series of experiments were carried out that were analyzed by statistical tools available in free software such as Python 3.7 and R version 4.0.1 together with R studio version 1.3.959. Applying the electrolytic process to a biomass solution of Chlorella vulgaris cultivated and supplied by CEBIAQUA from the Dep. Of Eng. De Pesca de UFC, acclimated in the culture medium urea and triple superphosphate (SPT), which corresponds to an alternative synthetic medium containing the nutrients necessary for microalgae growth, removal efficiency above 90% was obtained after 10 minutes of application of the process using a set of aluminum plates connected in parallel and using pulsed direct current. Electrocoagulation followed by a rest time of at least 10 minutes proved to be efficient as a method of harvesting microalgal biomass from a liquid medium and still electrodissolving a small amount of the anode. The experiments carried out in batch flow and pulsed current showed lower operating cost and greater efficiency in removing Chlorella vulgaris biomass. The live biomass of Chlorella vulgaris proved to be less costly and more efficient in removing copper and nickel ions from a synthetic solution after 30 minutes of application of the electrolytic process. When treating 2.0L of a real effluent through the electrolytic process coupled with the addition of microalgae Chlorella vulgaris in 30 minutes of process using pulsed current, 240 Hz pulse frequency, 2 aluminum plates as electrode, batch flow, 200 rpm stirring, without adding support electrolyte and initial pH between 7 and 7.5, a nickel removal of 50.54% was obtained when using the 70% microalgae and 30% effluent (v/v) ratio.