Mine Planning and Equipment Selection Supply Chain of Rare Earth Elements (REEs)

Abstract

Abstract. Thousands of electronics, aerospace, military, automotive, cleantech and renewable energy technologies rely on a range of rare earth elements (REEs) because of their unique physicochemical properties. Given their relative abundance in the earth's crust, however, they seldom occur in concentrated forms in economically exploitable ore deposits. The production can be technically challenging and require substantial and dedicated mineralogical, chemical and processing expertise. Furthermore, the chemical extraction processes have generated several environmental problems.This paper provides an overview of the supply chain for REEs, which generally consists of mining, processing, separation, application and recycling. The supply chain for rare earths can provide a useful context to analyze geological, technical, economic, environmental and social impact factors, and, moreover, it reflects the potential of recycling and reusing materials from finished applications. Subsequently, a more in-depth analysis of opportunities and uncertainties across the supply chain serving as a basis for procurement strategies of REEs will be highlighted.

Urban mining as a contribution to the resource strategy of the Canton of Zurich

“…It is believed that about 15% of the LREE and 50% of the HREE produced in China in 2012 came from unregulated production (Moores and Elliott, 2012). Some well documented environmental effects of REE mining include surface and groundwater contamination, erosion, heavy metal contamination, acidification of soils, reduction of vegetation, a reduction of agricultural yield as well as an increase of natural hazards like landslides and flooding (The People's Republic of China, 2012; U.S. EPA, 2012; Liu and Bongaerts, 2014). Chinese attempts to reduce environmental impacts include the introduction of target-and threshold values for the chemical oxygen demand, CO 2 , NH 3 , NO x , SO x , phosphorous, fluorine and thorium as well as heavy metal and particulate matter (The People's Republic of China, 2012; Liu and Bongaerts, 2014).…”

A Review of Rare Earth Mineral Processing Technology

“…Liu and Bongaerts had posited that most RE is mined by three conventional mining techniques, namely surface mining (i.e., open pit mining), underground mining and in-situ leaching. 26 Open pit technique is commonly employed in RE separation such as Bayan Obo mine (China), Mountain Pass mine (United States) and Mount Weld mine (Australia). This method involves removing the ores from the walls of the tunnels by blasting, excavating, which is followed by the ores being transported to the surface for the following process.…”

“…The main unit operation in beneficiation process consists of sizing unit (i.e., crushing and grinding) and the separation of REO from other minerals either by means of froth floatation (i.e., mixer, froth flotation cell, concentrator), magnetic separation, and gravity separation, followed by dewatering the minerals (i.e., thickening and drying). 26 The RE ores are usually found to be combined with barite, fluorite, calcite, silicates and iron minerals which can be quite challenging to separate between RE minerals from other associations. 26,33,34 Each of the processes has increased the concentration of REEs.…”

“…26 The RE ores are usually found to be combined with barite, fluorite, calcite, silicates and iron minerals which can be quite challenging to separate between RE minerals from other associations. 26,33,34 Each of the processes has increased the concentration of REEs. Firstly, the REO ores may go through the jaw crusher and ball mill to reduce the ores' sizes.…”

“…[24][25] Besides, ion-adsorption clays (i.e., weather crust elution deposit rare earths) are also considered as one of the major types of REE ores. 5,26 These deposits have indicated relatively higher weathered REE-rich rocks which are developed from chemical weathering under particular climatic changes. 5 In contrast, the other two sources are loparite and apatite which are also considered as RE sources.…”