aboveground processing
Quick Summary
Aboveground processing, in the context of mineral extraction, refers to the treatment of ore after it has been mined to separate valuable minerals from waste rock (gangue). This typically involves crushing the ore into fine particles and then using concentration processes.12
One common method is flotation separation, particularly for sulfide ores. In this process, the crushed ore is mixed with water and chemicals, then agitated with air. The mineral particles attach to the chemicals and float to the surface in a froth, while the waste rock sinks. Other concentration methods exploit differences in mineral properties such as color (optical sorting), density (gravity separation), magnetic properties (magnetic separation), or electrical charges (electrostatic separation).12
After concentration, the material is often dewatered through filtration or thickening before further processing or transport. Aboveground processing is a crucial step in preparing ores for extractive metallurgy.2
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oil shalePyrolysisā¦been designed for use in aboveground retorts as well as in situ. Three technologies that use this approach are the Kiviter process, employed in Estonia; the Fushun process of China; and the Paraho Direct process, designed in the United States. Hot-recycled-solids methods circulate either burned shale or an inert materialā¦
Read Moreā¦been designed for use in aboveground retorts as well as in situ. Three technologies that use this approach are the Kiviter process, employed in Estonia; the Fushun process of China; and the Paraho Direct process, designed in the United States. Hot-recycled-solids methods circulate either burned shale or an inert materialā¦
Read More- oil shalePyrolysis
ā¦Indirect process, both employed in aboveground retorts. Reactive fluids work in much the same manner as externally heated gas, but with a chemically reactive fluid such as high-pressure hydrogen. Hydrogen also partly upgrades the oil by removing sulfur and stabilizing reactive hydrocarbons. Reactive fluid technologies have been designed for abovegroundā¦
Read Moreā¦Indirect process, both employed in aboveground retorts. Reactive fluids work in much the same manner as externally heated gas, but with a chemically reactive fluid such as high-pressure hydrogen. Hydrogen also partly upgrades the oil by removing sulfur and stabilizing reactive hydrocarbons. Reactive fluid technologies have been designed for abovegroundā¦
Read More - oil shaleSurface processing
ā¦steps are involved in the aboveground processing of oil shale: mining the ore (either through underground or surface mining), crushing the ore to a size that can be handled by the retort, retorting (heating) the crushed shale to pyrolysis temperatures, and upgrading the oil obtained by pyrolysis of the organicā¦
Read Moreā¦steps are involved in the aboveground processing of oil shale: mining the ore (either through underground or surface mining), crushing the ore to a size that can be handled by the retort, retorting (heating) the crushed shale to pyrolysis temperatures, and upgrading the oil obtained by pyrolysis of the organicā¦
Read More - oil shaleUpgrading
ā¦upgrading than oil produced in aboveground retorting. Nevertheless, various upgrading steps are required, including hydrotreating, in part using the higher hydrogen content of the wellhead product. In addition, gas produced from in situ retorting is likely to be āsourāāthat is, containing hydrogen sulfide and carbon dioxide, and those impurities tooā¦
Read Moreā¦upgrading than oil produced in aboveground retorting. Nevertheless, various upgrading steps are required, including hydrotreating, in part using the higher hydrogen content of the wellhead product. In addition, gas produced from in situ retorting is likely to be āsourāāthat is, containing hydrogen sulfide and carbon dioxide, and those impurities tooā¦
Read More