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Optimization of Rock Salt Washing Process to Remove Selected Chemical Impurities in Lake Katwe Rock Salt

Received: 6 May 2023     Accepted: 22 May 2023     Published: 31 May 2023
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Abstract

Rich deposits of mineral salts, present in substantial economic quantities, characterize the geological bounty of Uganda. The primary location of this wealth is lake Katwe, a saline crater lake southwest of the country. However, all grades of rock salt extracted from Lake Katwe remain contaminated with chemical impurities such as calcium, magnesium, heavy metals and sulphate ions, even after solar evaporation process from the salt pans. There is a need to conduct research into possible contaminant removal methods which could increase the market value of the extracted salt, and add to the body of knowledge for future salt processing and chlor-alkali industries in Uganda. This study examined the effect of varying water volumes and temperature on the levels of Calcium, Magnesium and Sulphate ions in rock salt samples from Lake Katwe. The samples were methodically crushed and washed. The salt was then dissolved, crystallized, dried and meticulous analysis to determine the concentration of these impurities was carried out. The data was analysed and represented in Microsoft Excel and MATLAB. Results obtained revealed that a temperature of 40°C and salt-water ratio of 1:2 are the optimal parameters for maximum reduction of calcium, magnesium and sulphate impurities in rock salt. This analysis enhances the purity of salt harvested from Lake Katwe’s solar evaporation process and offers optimal washing parameters to reduce impurities in brine, thereby improving plant yield and reducing production costs across various salt grades. It also provides new information to the mining communities at Lake Katwe on how to affordably improve the percentage purity of their rock salt. The study will also contribute novel industry-tailored data for future prospective salt processing and chlor-alkali industrial plants near the Lake while also filling a knowledge gap for further research on rock salt purification.

Published in American Journal of Applied and Industrial Chemistry (Volume 7, Issue 1)
DOI 10.11648/j.ajaic.20230701.12
Page(s) 8-16
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2023. Published by Science Publishing Group

Keywords

Rock Salt, Chemical Impurities, Salt Washing, Temperature, Composition, Lake Katwe

References
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[10] H. Kasedde, A. Namagambe, J. Ddumba and J. Kirabira, “Numerical modelling of a solar salt pan for improved salt production at Lake Katwe, Uganda,” Case Studies in Thermal Engineering, vol. 42, p. 102592, 2023.
[11] J, Lwanyaga, H. Kasedde, J. B. Kirabira, “Phase diagram modeling of a multicomponent aqueous solution of Katwe Salt Lake, Uganda”, 16th International Conference on Environmental Science and Technology, 2019.
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[18] J. Amigo, F. Meza, F. Suarez, “A transient model for temperature prediction in a salt-gradient solar pond and the ground beneath it”, Energy, 2017.
[19] M. Aramesh, F. Pourfayaz, A. Kasaeian, “Transient heat extraction modeling method for a rectangular type salt gradient solar pond”, Energy Conservation Management, vol. 132, 2017.
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[24] B. Sawadogo, Y. Konate, S. Kossi, N. Fassouma, A. Wahab, H. Karambiri, “Removal of Sulphate Ions from Borehole Water Using Nanofiltration and Reverse Osmosis” in Water, vol. 14, 2022.
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Cite This Article
  • APA Style

    Mirembe Sophia Katooko, Wanasolo William, Serwadda Joseph, Kasule Hannah Talinda, Katuhamye Silas, et al. (2023). Optimization of Rock Salt Washing Process to Remove Selected Chemical Impurities in Lake Katwe Rock Salt. American Journal of Applied and Industrial Chemistry, 7(1), 8-16. https://doi.org/10.11648/j.ajaic.20230701.12

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    ACS Style

    Mirembe Sophia Katooko; Wanasolo William; Serwadda Joseph; Kasule Hannah Talinda; Katuhamye Silas, et al. Optimization of Rock Salt Washing Process to Remove Selected Chemical Impurities in Lake Katwe Rock Salt. Am. J. Appl. Ind. Chem. 2023, 7(1), 8-16. doi: 10.11648/j.ajaic.20230701.12

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    AMA Style

    Mirembe Sophia Katooko, Wanasolo William, Serwadda Joseph, Kasule Hannah Talinda, Katuhamye Silas, et al. Optimization of Rock Salt Washing Process to Remove Selected Chemical Impurities in Lake Katwe Rock Salt. Am J Appl Ind Chem. 2023;7(1):8-16. doi: 10.11648/j.ajaic.20230701.12

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  • @article{10.11648/j.ajaic.20230701.12,
      author = {Mirembe Sophia Katooko and Wanasolo William and Serwadda Joseph and Kasule Hannah Talinda and Katuhamye Silas and Kivumbi Achileo},
      title = {Optimization of Rock Salt Washing Process to Remove Selected Chemical Impurities in Lake Katwe Rock Salt},
      journal = {American Journal of Applied and Industrial Chemistry},
      volume = {7},
      number = {1},
      pages = {8-16},
      doi = {10.11648/j.ajaic.20230701.12},
      url = {https://doi.org/10.11648/j.ajaic.20230701.12},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajaic.20230701.12},
      abstract = {Rich deposits of mineral salts, present in substantial economic quantities, characterize the geological bounty of Uganda. The primary location of this wealth is lake Katwe, a saline crater lake southwest of the country. However, all grades of rock salt extracted from Lake Katwe remain contaminated with chemical impurities such as calcium, magnesium, heavy metals and sulphate ions, even after solar evaporation process from the salt pans. There is a need to conduct research into possible contaminant removal methods which could increase the market value of the extracted salt, and add to the body of knowledge for future salt processing and chlor-alkali industries in Uganda. This study examined the effect of varying water volumes and temperature on the levels of Calcium, Magnesium and Sulphate ions in rock salt samples from Lake Katwe. The samples were methodically crushed and washed. The salt was then dissolved, crystallized, dried and meticulous analysis to determine the concentration of these impurities was carried out. The data was analysed and represented in Microsoft Excel and MATLAB. Results obtained revealed that a temperature of 40°C and salt-water ratio of 1:2 are the optimal parameters for maximum reduction of calcium, magnesium and sulphate impurities in rock salt. This analysis enhances the purity of salt harvested from Lake Katwe’s solar evaporation process and offers optimal washing parameters to reduce impurities in brine, thereby improving plant yield and reducing production costs across various salt grades. It also provides new information to the mining communities at Lake Katwe on how to affordably improve the percentage purity of their rock salt. The study will also contribute novel industry-tailored data for future prospective salt processing and chlor-alkali industrial plants near the Lake while also filling a knowledge gap for further research on rock salt purification.},
     year = {2023}
    }
    

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  • TY  - JOUR
    T1  - Optimization of Rock Salt Washing Process to Remove Selected Chemical Impurities in Lake Katwe Rock Salt
    AU  - Mirembe Sophia Katooko
    AU  - Wanasolo William
    AU  - Serwadda Joseph
    AU  - Kasule Hannah Talinda
    AU  - Katuhamye Silas
    AU  - Kivumbi Achileo
    Y1  - 2023/05/31
    PY  - 2023
    N1  - https://doi.org/10.11648/j.ajaic.20230701.12
    DO  - 10.11648/j.ajaic.20230701.12
    T2  - American Journal of Applied and Industrial Chemistry
    JF  - American Journal of Applied and Industrial Chemistry
    JO  - American Journal of Applied and Industrial Chemistry
    SP  - 8
    EP  - 16
    PB  - Science Publishing Group
    SN  - 2994-7294
    UR  - https://doi.org/10.11648/j.ajaic.20230701.12
    AB  - Rich deposits of mineral salts, present in substantial economic quantities, characterize the geological bounty of Uganda. The primary location of this wealth is lake Katwe, a saline crater lake southwest of the country. However, all grades of rock salt extracted from Lake Katwe remain contaminated with chemical impurities such as calcium, magnesium, heavy metals and sulphate ions, even after solar evaporation process from the salt pans. There is a need to conduct research into possible contaminant removal methods which could increase the market value of the extracted salt, and add to the body of knowledge for future salt processing and chlor-alkali industries in Uganda. This study examined the effect of varying water volumes and temperature on the levels of Calcium, Magnesium and Sulphate ions in rock salt samples from Lake Katwe. The samples were methodically crushed and washed. The salt was then dissolved, crystallized, dried and meticulous analysis to determine the concentration of these impurities was carried out. The data was analysed and represented in Microsoft Excel and MATLAB. Results obtained revealed that a temperature of 40°C and salt-water ratio of 1:2 are the optimal parameters for maximum reduction of calcium, magnesium and sulphate impurities in rock salt. This analysis enhances the purity of salt harvested from Lake Katwe’s solar evaporation process and offers optimal washing parameters to reduce impurities in brine, thereby improving plant yield and reducing production costs across various salt grades. It also provides new information to the mining communities at Lake Katwe on how to affordably improve the percentage purity of their rock salt. The study will also contribute novel industry-tailored data for future prospective salt processing and chlor-alkali industrial plants near the Lake while also filling a knowledge gap for further research on rock salt purification.
    VL  - 7
    IS  - 1
    ER  - 

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Author Information
  • Department of Mining, Chemical and Petroleum Engineering, Faculty of Engineering, Kyambogo University, Kampala, Uganda

  • Department of Mining, Chemical and Petroleum Engineering, Faculty of Engineering, Kyambogo University, Kampala, Uganda

  • Department of Mining, Chemical and Petroleum Engineering, Faculty of Engineering, Kyambogo University, Kampala, Uganda

  • Department of Mining, Chemical and Petroleum Engineering, Faculty of Engineering, Kyambogo University, Kampala, Uganda

  • Department of Mining, Chemical and Petroleum Engineering, Faculty of Engineering, Kyambogo University, Kampala, Uganda

  • Department of Mining, Chemical and Petroleum Engineering, Faculty of Engineering, Kyambogo University, Kampala, Uganda

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