AVALIAÇÃO DO POTENCIAL BIOTECNOLÓGICO PARA O TRATAMENTO DE UM MINÉRIO DE OURO DE UMA MINA DO ESTADO DO AMAPÁ
EVALUATION OF BIOTECNOLOGICAL POTENCIAL FOR TREATING OF A ONE GOLD ORE FROM A MINE OF AMAPÁ STATE
Grangeiro, Luana Cardoso; Bevilaqua, Denise; Oliveira, Kleber Bittencourt; Palmieri, Mauricio Cesar; Macêdo, Emanuel Negrão
Resumo
O presente trabalho avaliou a melhor rota biotecnológica para o pré-tratamento de um minério aurífero e o efeito destes tratamentos na avaliação do consumo de cianeto durante a cianetação. Para este fim, testes de bioxidação foram conduzidos em escala de laboratório utilizando um minério aurífero (90g/ton Au) proveniente de uma mina situada no Estado do Amapá, Brasil. As culturas bacterianas utilizadas nos testes biológicos foram Acidithiobacillus ferrooxidans, linhagem LR e Acidithiobacillus thiooxidans, linhagem FG01. Os produtos do processo de bioxidação foram submetidos a ensaios de cianetação para testes de avaliação de consumo de cianeto e recuperação de ouro. Os estudos experimentais realizados mostraram que após 24h de cianetação da amostra mineral sem tratamento a recuperação de ouro foi de 93% (32 mg/L) com o consumo de NaCN de 2,86 kg.t-1, enquanto a melhor extração entre as amostras bioxidadas foi a do biorreator R2 de condição oxidante com 87% (30 mg/L) de ouro, e com consumo de 2,64 kg.t-1 de NaCN. Os resultados obtidos mostraram a viabilidade da técnica de bioxidação antes da cianetação para a redução no consumo de cianeto
Palavras-chave
Abstract
The aim of this work was to study the best biotechnology route for the pretreatment of the gold ore in order to reduce cyanide consumption during the conventional cyanidation and increasing the gold recovery. For this purpose, biological tests have been investigated at laboratory scale on a gold ore sample coming from Estado do Amapá, Brazil (90 g/ton). Bacterial cultures utilized in the biological tests of 20 days consisted of Acidithiobacillus ferrooxidans LR and Acidithiobacillus thiooxidans FG01. The biooxidated samples were submitted to cyanidation tests for gold recovery and tests of consumption of cyanide. Experimental studies demonstrated that after 24h leaching time by direct cyanidation, the gold recovery was 93% (32 mg/L) with a cyanide consumption of 2,84 kg.t-1, while the best gold extraction between biooxidated samples was from bioreactor R2 with 87% (30 mg/L), and the cyanide consumption of 2,64 kg.t-1. Experimental results have shown the technical feasibility of the biooxidative prior to convencional leaching for reducing the consumption of reagent cyanide
Keywords
Referências
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