A Lantern Retort for Small-Scale Gold Extraction

Richard Kwasi Amankwah; Grace Ofori-Sarpong

doi:doi:10.11648/j.ijepp.20140205.13

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A Lantern Retort for Small-Scale Gold Extraction

Richard Kwasi Amankwah, Grace Ofori-Sarpong

Published in International Journal of Environmental Protection and Policy (Volume 2, Issue 5)

Received: 25 August 2014 Accepted: 5 September 2014 Published: 20 September 2014

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Abstract

Two major retorts used in small-scale gold mining operations to reduce mercury emissions, during amalgam distillation are the steel and thermex retorts. Steel retorts are not very popular due to the reported darkening of gold after retorting. In addition, its opaque nature prevents miners from observing the process directly. The Thermex glass retort introduced by the United Nations Industrial Development Organisation (UNIDO) is also not patronised due to the extended heating periods resulting from the low thermal conductivity of glass. This paper describes a new retort, the Lantern retort, a combination of highly conductive steel with transparent glass, and therefore, a potential solution to the above concerns. The Lantern retort has a shorter warm-up and amalgam distillation time, and the rate of heating is 1.81oC/s while that of the Thermex is 1.49oC/s. For an amalgam of mass 20 g, 900 s was required to carry out complete distillation in the Lantern retort as against 2100 s in the Thermex. The height of the distillation column of the Lantern retort required to reduce mercury loss to below 1%, as it is with the Thermex retort, is 2.5 cm. Other advantages of the Lantern retort are that, it is less expensive and can withstand the harsh terrain of small-scale gold mining.

Published in	International Journal of Environmental Protection and Policy (Volume 2, Issue 5)
DOI	10.11648/j.ijepp.20140205.13
Page(s)	161-167
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), 2024. Published by Science Publishing Group

Keywords

Small-scale Mining, Gold, Mercury, Amalgamation, Retorting, Lantern Retort

References

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APA Style

Richard Kwasi Amankwah, Grace Ofori-Sarpong. (2014). A Lantern Retort for Small-Scale Gold Extraction. International Journal of Environmental Protection and Policy, 2(5), 161-167. https://doi.org/10.11648/j.ijepp.20140205.13

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ACS Style

Richard Kwasi Amankwah; Grace Ofori-Sarpong. A Lantern Retort for Small-Scale Gold Extraction. Int. J. Environ. Prot. Policy 2014, 2(5), 161-167. doi: 10.11648/j.ijepp.20140205.13

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AMA Style

Richard Kwasi Amankwah, Grace Ofori-Sarpong. A Lantern Retort for Small-Scale Gold Extraction. Int J Environ Prot Policy. 2014;2(5):161-167. doi: 10.11648/j.ijepp.20140205.13

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@article{10.11648/j.ijepp.20140205.13,
  author = {Richard Kwasi Amankwah and Grace Ofori-Sarpong},
  title = {A Lantern Retort for Small-Scale Gold Extraction},
  journal = {International Journal of Environmental Protection and Policy},
  volume = {2},
  number = {5},
  pages = {161-167},
  doi = {10.11648/j.ijepp.20140205.13},
  url = {https://doi.org/10.11648/j.ijepp.20140205.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijepp.20140205.13},
  abstract = {Two major retorts used in small-scale gold mining operations to reduce mercury emissions, during amalgam distillation are the steel and thermex retorts. Steel retorts are not very popular due to the reported darkening of gold after retorting. In addition, its opaque nature prevents miners from observing the process directly. The Thermex glass retort introduced by the United Nations Industrial Development Organisation (UNIDO) is also not patronised due to the extended heating periods resulting from the low thermal conductivity of glass. This paper describes a new retort, the Lantern retort, a combination of highly conductive steel with transparent glass, and therefore, a potential solution to the above concerns. The Lantern retort has a shorter warm-up and amalgam distillation time, and the rate of heating is 1.81oC/s while that of the Thermex is 1.49oC/s. For an amalgam of mass 20 g, 900 s was required to carry out complete distillation in the Lantern retort as against 2100 s in the Thermex. The height of the distillation column of the Lantern retort required to reduce mercury loss to below 1%, as it is with the Thermex retort, is 2.5 cm. Other advantages of the Lantern retort are that, it is less expensive and can withstand the harsh terrain of small-scale gold mining.},
 year = {2014}
}

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TY  - JOUR
T1  - A Lantern Retort for Small-Scale Gold Extraction
AU  - Richard Kwasi Amankwah
AU  - Grace Ofori-Sarpong
Y1  - 2014/09/20
PY  - 2014
N1  - https://doi.org/10.11648/j.ijepp.20140205.13
DO  - 10.11648/j.ijepp.20140205.13
T2  - International Journal of Environmental Protection and Policy
JF  - International Journal of Environmental Protection and Policy
JO  - International Journal of Environmental Protection and Policy
SP  - 161
EP  - 167
PB  - Science Publishing Group
SN  - 2330-7536
UR  - https://doi.org/10.11648/j.ijepp.20140205.13
AB  - Two major retorts used in small-scale gold mining operations to reduce mercury emissions, during amalgam distillation are the steel and thermex retorts. Steel retorts are not very popular due to the reported darkening of gold after retorting. In addition, its opaque nature prevents miners from observing the process directly. The Thermex glass retort introduced by the United Nations Industrial Development Organisation (UNIDO) is also not patronised due to the extended heating periods resulting from the low thermal conductivity of glass. This paper describes a new retort, the Lantern retort, a combination of highly conductive steel with transparent glass, and therefore, a potential solution to the above concerns. The Lantern retort has a shorter warm-up and amalgam distillation time, and the rate of heating is 1.81oC/s while that of the Thermex is 1.49oC/s. For an amalgam of mass 20 g, 900 s was required to carry out complete distillation in the Lantern retort as against 2100 s in the Thermex. The height of the distillation column of the Lantern retort required to reduce mercury loss to below 1%, as it is with the Thermex retort, is 2.5 cm. Other advantages of the Lantern retort are that, it is less expensive and can withstand the harsh terrain of small-scale gold mining.
VL  - 2
IS  - 5
ER  -

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Author Information

Richard Kwasi Amankwah

Mineral Engineering Department, University of Mines and Technology, Tarkwa, P. O. Box 237, Ghana
Grace Ofori-Sarpong

Mineral Engineering Department, University of Mines and Technology, Tarkwa, P. O. Box 237, Ghana

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Plain Text BibTeX RIS

APA Style

Richard Kwasi Amankwah, Grace Ofori-Sarpong. (2014). A Lantern Retort for Small-Scale Gold Extraction. International Journal of Environmental Protection and Policy, 2(5), 161-167. https://doi.org/10.11648/j.ijepp.20140205.13

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ACS Style

Richard Kwasi Amankwah; Grace Ofori-Sarpong. A Lantern Retort for Small-Scale Gold Extraction. Int. J. Environ. Prot. Policy 2014, 2(5), 161-167. doi: 10.11648/j.ijepp.20140205.13

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AMA Style

Richard Kwasi Amankwah, Grace Ofori-Sarpong. A Lantern Retort for Small-Scale Gold Extraction. Int J Environ Prot Policy. 2014;2(5):161-167. doi: 10.11648/j.ijepp.20140205.13

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@article{10.11648/j.ijepp.20140205.13,
  author = {Richard Kwasi Amankwah and Grace Ofori-Sarpong},
  title = {A Lantern Retort for Small-Scale Gold Extraction},
  journal = {International Journal of Environmental Protection and Policy},
  volume = {2},
  number = {5},
  pages = {161-167},
  doi = {10.11648/j.ijepp.20140205.13},
  url = {https://doi.org/10.11648/j.ijepp.20140205.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijepp.20140205.13},
  abstract = {Two major retorts used in small-scale gold mining operations to reduce mercury emissions, during amalgam distillation are the steel and thermex retorts. Steel retorts are not very popular due to the reported darkening of gold after retorting. In addition, its opaque nature prevents miners from observing the process directly. The Thermex glass retort introduced by the United Nations Industrial Development Organisation (UNIDO) is also not patronised due to the extended heating periods resulting from the low thermal conductivity of glass. This paper describes a new retort, the Lantern retort, a combination of highly conductive steel with transparent glass, and therefore, a potential solution to the above concerns. The Lantern retort has a shorter warm-up and amalgam distillation time, and the rate of heating is 1.81oC/s while that of the Thermex is 1.49oC/s. For an amalgam of mass 20 g, 900 s was required to carry out complete distillation in the Lantern retort as against 2100 s in the Thermex. The height of the distillation column of the Lantern retort required to reduce mercury loss to below 1%, as it is with the Thermex retort, is 2.5 cm. Other advantages of the Lantern retort are that, it is less expensive and can withstand the harsh terrain of small-scale gold mining.},
 year = {2014}
}

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TY  - JOUR
T1  - A Lantern Retort for Small-Scale Gold Extraction
AU  - Richard Kwasi Amankwah
AU  - Grace Ofori-Sarpong
Y1  - 2014/09/20
PY  - 2014
N1  - https://doi.org/10.11648/j.ijepp.20140205.13
DO  - 10.11648/j.ijepp.20140205.13
T2  - International Journal of Environmental Protection and Policy
JF  - International Journal of Environmental Protection and Policy
JO  - International Journal of Environmental Protection and Policy
SP  - 161
EP  - 167
PB  - Science Publishing Group
SN  - 2330-7536
UR  - https://doi.org/10.11648/j.ijepp.20140205.13
AB  - Two major retorts used in small-scale gold mining operations to reduce mercury emissions, during amalgam distillation are the steel and thermex retorts. Steel retorts are not very popular due to the reported darkening of gold after retorting. In addition, its opaque nature prevents miners from observing the process directly. The Thermex glass retort introduced by the United Nations Industrial Development Organisation (UNIDO) is also not patronised due to the extended heating periods resulting from the low thermal conductivity of glass. This paper describes a new retort, the Lantern retort, a combination of highly conductive steel with transparent glass, and therefore, a potential solution to the above concerns. The Lantern retort has a shorter warm-up and amalgam distillation time, and the rate of heating is 1.81oC/s while that of the Thermex is 1.49oC/s. For an amalgam of mass 20 g, 900 s was required to carry out complete distillation in the Lantern retort as against 2100 s in the Thermex. The height of the distillation column of the Lantern retort required to reduce mercury loss to below 1%, as it is with the Thermex retort, is 2.5 cm. Other advantages of the Lantern retort are that, it is less expensive and can withstand the harsh terrain of small-scale gold mining.
VL  - 2
IS  - 5
ER  -

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