AVALIAÇÃO DE TAMANHO DE BOLHAS EM COLUNA DE FLOTAÇÃO POR ANÁLISE DE IMAGEM USANDO OS SOFTWARES IMAGEJ E APBS
EVALUATION OF BUBBLE SIZE IN A FLOTATION COLUMN BY IMAGE ANALYSIS USING THE SOFTWARES IMAGEJ AND APBS
Renata Nigri de Almeida, Estevão Gomes da Cruz Barreto, Hudson Jean Bianquini Couto,
Resumo
O tamanho médio e a distribuição de tamanho de bolhas (DTB) são variáveis importantes no processo de flotação, pois influenciam diretamente na eficiência de coleta e no transporte das partículas. Neste contexto, o objetivo deste trabalho foi medir e avaliar o tamanho médio e a DTB geradas em uma coluna de flotação em função de algumas variáveis importantes do processo de flotação. Para captura e visualização das bolhas foi utilizado o equipamento Anglo Platinum Bubble Sizer (APBS). As imagens das bolhas capturadas foram processadas com utilização de dois softwares, o APBS e o ImageJ, de forma a comparar os resultados obtidos por ambos. Além de calcular o diâmetro médio e a DTB das bolhas, foi possível realizar medidas de holdup de gás (Ɛg ) e da concentração crítica de coalescência (CCC) para o Flotanol D14, agente tensoativo avaliado no trabalho. Os resultados obtidos de Ɛg e CCC apontaram para uma boa concordância com os valores encontrados na literatura. Considerou-se o ImageJ mais confiável para o processamento de imagem e análise do tamanho de bolha devido ao seu maior controle das etapas de processamento.
Palavras-chave
Abstract
The average size and the bubble size distribution (BSD) are important variables in the flotation process, as they influence the efficiency on collecting and transporting the particles. In this context, the aim of this work was to measure and evaluate the average size and BSD generated in a flotation column as a function of some important variables of the flotation process. The Anglo Platinum Bubble Sizer (APBS) was used to capture and visualize the bubbles. The images of the captured bubbles were processed using two softwares, the APBS and the ImageJ (public domain), in order to compare the results obtained by both. In addition to calculating the diameter of the bubbles, it was possible to perform measurements of gas holdup (Ɛg ) and critical coalescence concentration (CCC) for Flotanol D14, surfactant evaluated. The results obtained from Ɛg and CCC showed a good agreement with the values found in the literature. The ImageJ software was considered more reliable for image processing and bubble size analysis due to its control of the processing step.
Keywords
Referências
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