Confection of ceramic bricks with biomass contaminated by cupper incorporation

Abstract

A fitorremediação por macrófitas aquáticas é uma técnica que vem sendo largamente estudada e tem mostrado resultados bastante satisfatórios. Esse processo gera, entretanto, grande quantidade de biomassa. Essa biomassa, quando contaminada por metais pesados, não pode ser descartada no meio ambiente. Assim, este trabalho analisou a viabilidade de reaproveitamento de biomassa de Pontederia parviflora na confecção de blocos cerâmicos. Para tanto, uma solução com concentração de 1.000 mg/L de cobre foi tratada por P. parviflora, por um período de 5 dias. As concentrações de cobre foram determinadas antes e após o período de tratamento. Corpos de prova de massa argilosa foram confeccionados com 5% e 10% de biomassa vegetal contaminada. A qualidade dos blocos foram analisadas conforme os principais testes descritos na literatura. O índice de remoção de cobre da solução, ao final do experimento, foi superior a 96% e o aumento da concentração desse metal na biomassa vegetal superou os 1.200%. Os resultados experimentais dos parâmetros analisados foram totalmente satisfeitos para todos os corpos de prova (CP) confeccionados com adição de 5% e, para a maioria dos CP que continham 10% foram satisfatórios, conforme determinações do IPT (1985), NBR 7170 (ABNT, 1983) e NBR 7171 (ABNT, 1992). Assim, afirma-se que o fitotratamento de efluentes contaminados com cobre por P. parviflora e o reaproveitamento de sua biomassa na confecção de blocos cerâmicos são viáveis.

Phytoremediation of Effluents Contaminated with Heavy Metals by Floating Aquatic Macrophytes Species

“…Among the main elements that can be remedied by plants are petroleum hydrocarbons, agrochemicals, explosives, chlorinated solvents and industrial byproducts, organic or even inorganic substances [25]. The focus of this chapter is related to heavy metals, which fit the last category mentioned and can also be related to the activities of mining [26], causing long-term toxic effects to those who eventually come into contact with them.…”

“…After remediation of the contaminated effluent or body of water, the biomass incorporates the metals and retains them, that is, it still has the bioaccumulated heavy metals that need to be removed from the contact with the medium and can be submitted to manual processes or even mechanics for the withdrawal of the vegetal specimens, reaching the stage of isolation of the vegetal mass, thus avoiding a new dispersion of the contaminants post extraction. However a final disposal is required, often subjecting it to harmful environments such as the deposit of these contaminants in landfill and incineration; the latter technique is mentioned as a proposal to reduce the volume of plants and to generate energy by means of heat, also contributing to the removal of metals [8], However, research suggests the incorporation of the biomass used in the treatment of ceramic blocks, proposing an efficient method of transformation of the products obtained, promoting a new environmentally acceptable use, without generating more contaminants and dispensing with incineration [26], also studies affirm that the incorporation of the vegetal components in the ceramic sector is possible because the clay favors in the inertization of the as a way of preserving natural resources and avoiding further degradation of the environment. In the same work are mentioned researches of incorporation of macrophytes used after the technique of phytoremediation with large amounts of copper and chromium, proving in both the viability of inclusion of a percentage of the biomass in the clay leading to the consequent inertization of metals [60].…”