Compositional and Structural Deficiencies Causing Failure of Local Fire Assaying Crucibles in Ghana

Abstract:

Locally produced crucibles in Ghana experience dimensional failures during fire assaying of ores, therefore, even with a higher cost, imported crucibles are still the most preferred choice by laboratories in Ghana because of the stable performance of up to three cycles. Assay crucibles of locally manufactured, imported and theoretically composed were sampled and analysed via reverse engineering to identify factors that are attributed to the failure during use. Field investigation and compositional, physical and structural investigations were carried out using XRD, water boiling and SEM-EDS analyses, respectively. The results indicated that failure of the local crucible can be attributed to low mullite phase in both content and planes, which could ease the crack development and enhance the thermal stability of the crucible; non converted quartz into cristobalite, which stabilises the volume expansion coefficient during the fire assaying cycles; excess quartz content and absence of alumina content weakened the corrosion resistance against attack from the basic flux of litharge; and high porosity, allowed penetration of molten charge into the structure of crucible, leading to the dissolution of free silica content into the charge and causing structural failure. To overcome such deficiencies, higher firing temperature (~1240 °C), extra soaking time, and blending of high alumina contained clay/minerals were suggested.

• Periodical: International Journal of Engineering Research in Africa (Volume 51)
• Pages: 57-70
• DOI: https://doi.org/10.4028/www.scientific.net/JERA.51.57
• Online since: November 2020
• Authors: Yongdan Hou, Lemuel Gbologah*, Derrick Boateng Asante, Parpah Senanu Kwawukume
• Keywords: Assaying Crucible, Composition, Failure, Structural Deficiencies

References

[1] E. L. Huffman, J. R. Clark, and J. R. Yeager, Gold analysis - Fire assaying and alternative methods,, Exploration and Mining Geology, vol. 7, no. 1–2. p.155–160, (1999).

[2] Reddi, G. S. and C. S. M. Rao, Analytical techniques for the determination of precious metals in geological and related materials,, Analyst, vol. 11, no. 3, p.1–8, (1999).

DOI: 10.1039/a904839a

[3] J. Haffty and Riley LB, A Manual on Fire Assaying and Determination of the Noble Metals in Geological Materials,, U.S Geol. Surv. Bull., vol. 1, no. 1445, p.1–56, (1977).

[4] R. A. Chesti, Refractories: Manufacture, properties and applications. Prentice- Hall of India, (1986).

[5] M. Martinón-Torres, T. Rehren, and I. C. Freestone, Mullite and the mystery of Hessian wares,, Nature, vol. 444, no. 7118, p.437–438, 2006,.

DOI: 10.1038/444437a

[6] H. Schneider and S. Komarneni, Basic properties of mullite,, in Mullite, Wiley – VCH Weinheim, 2005, p.141–155.

[7] M. Martinón-Torres, I. C. Freestone, A. Hunt, and T. Rehren, Mass-produced mullite crucibles in medieval Europe: Manufacture and material properties,, J. Am. Ceram. Soc., vol. 91, no. 6, p.2071–2074, 2008,.

DOI: 10.1111/j.1551-2916.2008.02383.x

[8] R. B. Asamoah et al., Industrial applications of clay materials from Ghana (a review),, Orient. J. Chem., vol. 34, no. 4, p.1719–1734, 2018,.

[9] ASTM International, Standard Test Methods for Apparent Porosity, Water Absorption, Apparent Specific Gravity, and Bulk Density of Burned Refractory Brick and Shapes by Boiling Water (ASTM C20-00),, ASTM Int. West Conshohocken, PA, vol. 00, no. July, p.3, 2000,.

DOI: 10.1520/c0020-00

[10] B. Kanka and H. Schneiider, Sintering mechanisms and microstructural development of coprecipitated mullite,, J. Mater. Sci., vol. 29, no. 5, p.1239–1249, (1994).

DOI: 10.1007/bf00975071

[11] K. G. Skinner, W. H. Cook, R. A. Potter, and H. A. Y. N. E. PALMOUR III, Effect of TiO2, Fe2O3, and alkali on mineralogical and physical properties of mullite‐type and mullite‐forming Al2O3‐SiO2 mixtures: I.,, J. Am. Ceram. Soc., vol. 36, no. 11, p.349–356, (1953).

DOI: 10.1111/j.1151-2916.1953.tb12816.x

[12] C. Sadik, I. E. El Amrani, and A. Albizane, Recent advances in silica-alumina refractory: A review,, J. Asian Ceram. Soc., vol. 2, no. 2, p.83–96, 2014,.

DOI: 10.1016/j.jascer.2014.03.001

[13] M. E. Tyrrell, Effects of impurities on sintered mullite,, (1962).

[14] E. A. Bochraraov, S. and Gemsimov, Technology of Silicate Materials. Engineering press, Bulgaria, (1977).

[15] A. C. Iyasara, E. C. Stan, O. Geoffrey, M. Joseph, N. N. Patrick, and N. Benjamin, Influence of Grog Size on the Performance of NSU Clay-Based Dense Refractory Bricks,, Am. J. Mater. Sci. Eng., vol. 4, no. 1, p.7–12, 2016,.

[16] C.-Y. Chen and W.-H. Tuan, Evolution of Mullite Texture on Firing Tape-Cast Kaolin Bodies,, J. Am. Ceram. Soc., vol. 85, no. 5, p.1121–1126, 2004,.

DOI: 10.1111/j.1151-2916.2002.tb00232.x

[17] W. E. Lee, G. P. Souza, C. J. McConville, T. Tarvornpanich, and Y. Iqbal, Mullite formation in clays and clay-derived vitreous ceramics,, J. Eur. Ceram. Soc., vol. 28, no. 2, p.465–471, 2008,.

DOI: 10.1016/j.jeurceramsoc.2007.03.009

[18] S. Lee, Y. J. Kim, and H.-S. Moon, Phase Transformation Sequence from Kaolinite to Mullite Investigated by an Energy-Filtering Transmission Electron Microscope,, J. Am. Ceram. Soc., vol. 82, no. 10, p.2841–2848, 2004,.

DOI: 10.1111/j.1151-2916.1999.tb02165.x

[19] M. Mizuno, Microstructure, Microchemistry, and Flexural Strength of Mullite Ceramics,, J. Am. Ceram. Soc., vol. 74, no. 12, p.3017–3022, 1991,.

DOI: 10.1111/j.1151-2916.1991.tb04295.x

[20] D. M. Ibrahim, S. M. Naga, Z. A. Kader, and E. A. Salam, Cordierite-mullite refractories,, Ceram. Int., vol. 21, no. 4, p.265–269, 1995,.

DOI: 10.1016/0272-8842(95)99792-a

[21] H. Schneider, J. Schreuer, and B. Hildmann, Structure and properties of mullite-A review,, J. Eur. Ceram. Soc., vol. 28, no. 2, p.329–344, 2008,.

[22] Y. F. Chen, M. C. Wang, and M. H. Hon, Phase transformation and growth of mullite in kaolin ceramics,, J. Eur. Ceram. Soc., vol. 24, no. 8, p.2389–2397, 2004,.

DOI: 10.1016/s0955-2219(03)00631-9

[23] J. B. Eggerding, C. L., Gonzales Jr, F., & Niklewski, Process for Forming Mullite,, no. 19, (1981).

[24] B. Schneider, H Schreuer, J and Hildmann, Structure and properties of mullite—a review,, J. Eur. Ceram. Soc., vol. 28, no. 2, p.329–344, 2008,.

[25] V. Viswabaskaran, F. D. Gnanam, and M. Balasubramanian, Mullitisation behaviour of calcined clay–alumina mixtures,, Ceram. Int., vol. 29, no. 5, p.561–571, (2003).

DOI: 10.1016/s0272-8842(02)00203-1

[26] T. Ebadzadeh, M. H. Sarrafi, and E. Salahi, "Microwave-assisted synthesis and sintering of mullite,, Ceram. Int., vol. 35, no. 8, p.3175–3179, (2009).

DOI: 10.1016/j.ceramint.2009.05.013

[27] M. A. Sainz, F. J. Serrano, J. M. Amigo, J. Bastida, and A. Caballero, XRD microstructural analysis of mullites obtained from kaolinite-alumina mixtures,, J. Eur. Ceram. Soc., vol. 20, no. 4, p.403–412, 2000,.

DOI: 10.1016/s0955-2219(99)00183-1

[28] N. S. Raut, P. Biswas, T. K. Bhattacharya, and K. Das, Effect of bauxite addition on densification and mullitization behaviour of West Bengal clay,, Bull. Mater. Sci., vol. 31, no. 7, p.995–999, 2008,.

DOI: 10.1007/s12034-008-0156-4

[29] S. Samal, A. K. Ray, and A. Bandopadhyay, Proposal for resources, utilization and processes of red mud in India—a review,, Int. J. Miner. Process., vol. 118, p.43–55, 2013,.

DOI: 10.1016/j.minpro.2012.11.001

[30] M. Sardy, A. Arib, K. El Abbassi, and M. Gomina, Elaboration and Characterization of Mullite Refractory Products from Moroccan Andalusite,, New J. Glas. Ceram., vol. 02, no. 03, p.121–125, 2012,.

DOI: 10.4236/njgc.2012.23017

[31] L. C. S. Zichen, "Mineralogy of High Alumina Clay-Bauxite Deposits in Shanxi and Henan Provinces,, Acta Sedimentol. Sin. 2, vol. 2, (1985).

[32] G. O. Kesse, The mineral and rock resources of Ghana. AA Balkema Publishers, Accord, MA, (1985).

[33] J. R. Dankwah, A. Y. Fosu, N. Fosu, and P. Koshy, Carbothermal Upgrading of the Awaso Bauxite Ore using Waste Pure Water Sachets as Reductant,, Ghana Min. J., vol. 15, no. 1, p.64–72, (2015).

DOI: 10.4314/gm.v16i2.8

[34] A. V. Maldhure, H. S. Tripathi, A. Ghosh, and S. K. Das, Mullite-Corundum Composites from Bauxite: Effect of Chemical Composition,, Trans. Indian Ceram. Soc., vol. 73, no. 1, p.31–36, 2014,.

DOI: 10.1080/0371750x.2013.870050

[35] C. Xu, Preparation and performance of an advanced multiphase composite ceramic material,, J. Eur. Ceram. Soc., vol. 25, no. 5, p.605–611, 2005,.

[36] B. J. Swanson, P. L., Fairbanks, C. J., Lawn, B. R., MAI, Y. W., & Hockey, "Crack‐interface grain bridging as a fracture resistance I, mechanism in ceramics: I, experimental study on alumina,, J. Am. Ceram. Soc., vol. 70, no. 4, p.279–289, (1987).

DOI: 10.1111/j.1151-2916.1987.tb04982.x

[37] A. S. Shado, O. J. Ajayi, and C. A. Umeh, The Effect of Grog Sizing on the Performance of Ire Ekiti Fire Clay Refractory Bricks,, (2018).