Tecnologia em Metalurgia, Materiais e Mineração
https://tecnologiammm.com.br/article/doi/10.4322/2176-1523.20191795
Tecnologia em Metalurgia, Materiais e Mineração
Artigo Original

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,

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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

Coluna de flotação; Tamanho de bolha; Análise de imagens.

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

Column flotation; Bubble size; Image analysis.

Referências

1 Alexander D, Manlapig E, Bradshaw D, Harbort G. Froth flotation. In: Wills BA, Napier-Munn TJ. Mineral processing technology. 7th ed. USA: Elsevier Science & Technology Books; 2006.

2 Rubio J, Souza ML, Smith RW. Overview of flotation as a wastewater treatment technique. Minerals Engineering. 2002;15:139-155.

3 Sivamohan R. The problem of recovering very fine particles in mineral processing – a review. International Journal of Mineral Processing. 1990;28:247-288.

4 Aquino JA, Oliveira MLM, Fernandes MD. Flotação em coluna. In: Luz AB, Sampaio JA, Almeida SLM. Tratamento de minérios. 5. ed. Rio de Janeiro: CETEM/MCT; 2010.

5 Cho YS, Laskowski JS. Effect of flotation frothers on bubble size and foam stability. International Journal of Mineral Processing. 2002;64:69-80.

6 Couto HJB, Nunes DG, Neumann R, França SCA. Micro-bubble size distribution measurements by laser diffraction technique. Minerals Engineering. 2009;22:330-335.

7 Finch JA, Dobby GS. Column flotation. USA: Pergamon Press; 1990.

8 Grau RA, Laskowski JS, Heiskanen K. Effect of frothers on bubble size. International Journal of Mineral Processing. 2005;76:225-233.

9 Leiva J, Vinnett L, Contreras F, Yianatos J. Estimation of the actual bubble surface area flux in flotation. Minerals Engineering. 2010;23:888-894.

10 Rodrigues RT, Rubio J. New basis for measuring the size distribution of bubbles. Minerals Engineering. 2003;16:757- 765.

11 Maldonado M, Desbiens A, Poulina É, del Villar R, Riquelme A. Automatic control of bubble size in a laboratory flotation column. International Journal of Mineral Processing. 2015;141:27-33.

12 Gulden SJ, Riedele C, Rollié S, Kopf M-H, Nirschl H. Online bubble size analysis in micro flotation. Chemical Engineering Science. 2018;185:168-181.

13 Rodrigues RT. Desenvolvimento da técnica LTM-BSizer para a caracterização de bolhas e a avaliação de parâmetros no processo de flotação [dissertação]. Porto Alegre: Universidade Federal do Rio Grande do Sul; 2004.

14 Abramoff MD, Magelhaes PJ, Ram SJ. Image Processing with ImageJ. Biophotonics International. 2004;11:36-42.

15 Gupta AK, Banerjee PK, Mishra A, Satish P, Pradip. Effect of alcohol and polyglycol ether frothers on foam stability, bubble size and coal flotation. International Journal of Mineral Processing. 2007;82:126-137.

16 Laskowski JS. Fundamental properties of flotation frothers. In: Lorenzen L, Bradshaw DJ. Proceedings 22nd International Mineral Processing Congress; 2003 November 23-26; Cape Town, South Africa. Marshalltown: South African Institute of Mining & Metallurgy; 2003. p. 788-797.

17 Braga AS, Pinto TCS, Matai PHLS, Leal LS Fo. Concentração micelar crítica e concentração crítica de coalescência de reagentes de flotação. Holos. 2015;7:140-147.

18 Veras MM, Baltar CAN, Paulo JBA, Leite, JYP. Comparative study of the main flotation frothers using a new HYDROMESS adapted technique. Rem: Revista Escola de Minas. 2014;67(1):87-92.

19 Mazahernasab R, Ahmadi R. Determination of bubble size distribution in a laboratory mechanical flotation cell by a laser diffraction technique. Physicochemical Problems of Mineral Processing. 2016;52(2):690-702.

20 Kuan SH. The effect of solids on gas holdup, bubble size and water overflow rate in flotation [dissertation]. Montreal: McGill University; 2009.

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