Bauxite Quality Index (BQI) as a New Criterion for The Bauxite Ore Quality: A Case Study

Document Type : Research Article

Authors

1 Geological survey and mineral exploration of Iran, Sari Center

2 Dept. of Geology, Faculty of Sciences, Golestan Univercity, Iran

3 Dept. of Statistics, Faculty of Sciences, Golestan Univercity, Iran

10.29252/anm.2019.9365.1324

Abstract

Summary
The Module Index (MI = Al2O3/SiO2) is a criterion for determining the ore quality in bauxite deposits. Despite the wide use of the MI, it cannot provide reliable criteria for determining of the ore quality due to less statistical attention to outlier data. In this paper, we have introduced the Bauxite Quality Index (BQI) as a new criterion for determining the bauxite ore quality. We used geochemical data of the Jajarm bauxite deposit to evaluate the ability of the mentioned index. The BQI could be able to classify the ore zones based on the ore quality and economic importance. The BQI would control the outlier data and reveal the relationship between the variables, which are the most important characteristics of this index.
 
Introduction
Bauxite is the most important source of aluminum. The quality of bauxite ore depends on the mineral composition of the ore which has been calculated by the Module index (Al2O3/SiO2). This paper introduces a more comprehensive bauxite quality index (BQI) than the MI, using multivariate statistical analysis. We applied geochemical data of the Jajarm bauxite deposit to evaluate the ability of the BQI.
 
Methodology and Approaches
The BQI is determined based on factor analysis of geochemical data of the Jajarm bauxite deposit. We investigated the relationships between ore quality and alumina-silica contents using the MI and BQI. Then, the economic potential of the ore zones was evaluated by either MI and BQI. Finally, the correlation coefficients of the different parameters were calculated, and all the obtained results were compared and discussed.
 
Results and Conclusions
The Bauxite Quality Index (BQI) is a new suggested criterion for the determination of bauxite ore quality. This criterion reveals the hidden relationships of Al2O3 and SiO2 with other variables and outlier data. Comparison of the MI and the BQI indicates that the BQI is more reliable than the MI in recognition of the high-grade ore bodies.

Keywords

Main Subjects

Full Text

اصطلاح بوکسیت برای اولین بار در سال 1821 توسط زمین‌شناسان فرانسوی برای توصیف لایه‌های رسی قرمز رنگ در ایالت بوکسیده1 در جنوب فرانسه که حاوی 52 درصد Al2O3 بود، مورد استفاده قرار گرفت]1[. کانسارهای بوکسیتی حاوی ترکیبی از اکسیدها و هیدروکسیدهای آلومینیوم و ناخالصی­های همچون کانی­های رسی، کوارتز، اکسیدهای آهن و مواد آمورف هستند. این کانسارها به عنوان منبع اصلی تأمین کننده آلومینیم محسوب می­شوند که با درجات کیفی متفاوت استخراج و بهره­برداری می­شود. استرالیا (82 میلیون تن)، چین (65 میلیون تن) و برزیل (5/34 میلیون تن) جزء بزرگ‌ترین کشورهای تولید کننده این عنصر به شمار می­روند]2[.

References

[1]           Angélicaa, R.S. Kahnb, H. Paz, S.P.A. (2018). "A proposal for bauxite quality control using the combined Rietveld - Le Bail - Internal Standard PXRD method – Part 2: Application to a gibbsitic bauxite from the Paragominas region, northern Brazil". Minerals Engineering. 122: (2018) 148–155.
[2]           Bray, E.L. (2017). "Bauxite and Alumina. In: Mineral Commodity Summaries", USGS pp. 32–33.
[3]           Shahriyari, M. (1986). "Reserves of bauxite Karst (bed carbonate)." Tehran University (In Persian).
[4]           Paza, S.P.A. Kahna, H. Angélica, R.S. (2018). "A proposal for bauxite quality control using the combined Rietveld – Le Bail – Internal Standard PXRD Method – Part 1: hkl model developed for kaolinite". Minerals Engineering, 118: 52-61.
[5]           Tutmez, B. (2018). "Bauxite Quality Classification by Shrinkage Methods". Journal of Geochemical Exploration, S0375-6742(17)30495-8.
[6]           Habashi, F. (2015). "A short history of hydrometallurgy", Hydrometallurgy. 79: 15-22.
[7]           Exploration of the Ministry of Mines and Metals. (1997). "Design and construction of mining equipment alumina factory." unpublished, (In Persian).
[8]           Engineers Khak Khub. (1991). "According to geological and tectonic Jajarm bauxite deposit." unpublished, (In Persian).
[9]           Jafarzadeh, R. (2000). "Evaluation of bauxite mineralogy Jajarm." Master Thesis, University of Shiraz, (In Persian).
[10]         Mollai, H. and Sharifian Atar, R (2006). "The study of texture and different phases constituting the Jajarm Bauxite minerals in northern Khurassan." Journal Of Crystallography and Mineralogy of Iran 14 (2): 339-366 (In Persian).
[11]         Ismaili, D. Esna-ashari, A. Rahimpour-Bonab, H. Amini fazl (2006). "Geochemistry of rare earth elements (REE) in Jajarm Bauxite Deposit (North East of Iran)." Journal of Earth Sciences, 62: 2-13 (In Persian).
[12]         Nasery, M. (2003). "Investigation of Geochemical Exploration of the bauxite deposit Jajarm the capabilities and limitations in industrial applications." Master Thesis, University of Mashhad Ferdosy. (In Persian).
[13]         Amini, L. Shamanian, Gh.h, Raghimi, M. Jafarzadeh, D. (2011) "Mineralogical, geochemical and genetical investigations of the Jajarm karst bauxite deposit, NE Iran." Journal of Crystallography and mineralogy of Iran." 3: 413-426 (In Persian).
[14]         Esmaeily, D. Rahimpour-Bonab, H. Esna-ashari, A. Kananian, A. (2010). "Petrography and Geochemistry of the Jajarm Karst Bauxite Ore Deposit, NE Iran: Implications for Source Rock Material and Ore Genesis." Turkish Journal of Earth Sciences 19: 267-284.
[15]         Amini, L. (2010). "Mineralogical and Geochemical Characteristics Investigation of the Jajarm Bauxite Deposit, Northern Khorasan Province, Iran", Master Thesis, University of Golestan (In Persian).
[16]         Pearson, K. (1901). "On lines and planes of closest fit to systems of points in space." Phil Magazine, 2: 559-572.
[17]         Loewen, Sh. Gonulal, T. (2015) "Exploratory Factor Analysis and Principal Components Analysis". Routledge, pp.182-212
[18]         Spearman, Ch. (1904). "General Intelligence, Objectively Determined and Measured." American Journal of Psychology, 15: 201-293.
Journal of Analytical and Numerical Methods in Mining Engineering
Volume 9, Issue 21
February 2020
Pages 59-67

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History

  • Receive Date: 13 March 2018
  • Revise Date: 28 August 2019
  • Accept Date: 04 November 2019

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