docRare earth oxide production: What are rare earths? Life Cycle Assessment methodology
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MSc in Environmental Systems Engineering Aländji BOUORAKIMA Supervisor: Julia STEGEMANN Rare earth oxide production: Assessment of the environmental impacts in two Chinese mines UCL Department of Civil, Environmental and Geomatic Engineering, Gower St, London ,WC1E 6BT What are rare earths? Rare earth elements are a group of 17 metals which, contrary to their name, are not all very rare Life Cycle Assessment methodology Modelling of Modelling of the the processes processes (beneficiation, (beneficiation, hydrometallurgy and and refining) refining) hydrometallurgy Inventory of Inventory of every every input input and and output output (energy, (energy, chemicals, wastes) wastes) chemicals, Assessment of Assessment of the the environmental environmentalimpacts impactsaccording based on to six different categories: six different categories: Relative abundance of rare earths elements in Earth’s crust (Haxel 2002) • Global warming • Radioactive waste generation • Acidification • Land use • Eutrophication • Toxicity in wastewater Why are rare earths important? They are used in several technological applications and particularly environmental friendly applications such as:Electric motors for hybrid Ni-MH batteries and electric vehicles Generators in wind turbine Computer hard disks Automotive catalysts (reduction of NOx and CO) Hydrogen storage devices Energy saving light bulbs LEDs and OLEDs Solid Oxide Fuel Cells Rare earth oxide production In 2010, 97% of the world production came from China Midpoint indicators Category Unit Bayan Obo Maoniuping CO2 emissions kg of CO2 6,450 5,940 Atmosphere acidification kg of SO2eq 124 779 Wastewater acidification kg of SO2eq 559 444 Wastewater eutrophication kg of H3PO4eq 428 n/a Radioactivity discharge Bq 5.3 10 7 3.7 10 7 Volume used m 95.4 n/a Oxalic acid C2H2O4 35 kg 35 kg Ammonium bicarbonate NH4HCO3 61 kg - Ammonium sulphates (NH4)2SO4 861 kg - - 327 kg Toxicity discharge in wastewater In China, only Bayan Obo and Maoniuping deposits produce light rare earth elements (La, Ce, Nd, Pr, Sm) They account for 70% of the world rare earth oxide production Question: What are the environmental impacts of producing rare earth oxides in Bayan Obo and Maoniuping? 3 Sodium sulphates Na2SO4 Conclusion The midpoint indicators show that considerable environmental impacts are related to the rare earth oxide production Rare earth production requires a strict waste management to avoid radioactive or toxic run-offs The processes of rare earth oxide production are very energy-intensive Reference: Haxel, G. B., Hedrick, J.B., Orris, G.J. (2002). "Rare earth elements: Critical resources for high technology", U.S. Geological Survey, available at: http://www.rareelementresources.com/i/pdf/fs087-02.pdf Last access: 31/08/2011.
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China Rare Earth Market - Industry Analysis and Forecast by Radiant Insights, Inc
The rare earth elements are naturally occurring non-toxic elements that have distinctive properties. These properties have made these elements essential to several rising technologies that contribute to energy efficiency, health, and environmental solutions.
There are numerous uses of these elements such as; Neodymium is utilized in radiation filtering & magnets, Yttrium is utilized in superconductors, microwave filters, & laser technology, Europium is utilized in laser technology, nuclear reactors, & televisions.
China is the leading rare earth elements supplier across the globe. In 2009, the global rare earth elements production was valued at 126,230 metric tons, with China producing about 95% of it.
China became the dominant market for rare earth elements when it started producing & supplying these elements at prices that no other western manufacturer could compete with. It is anticipated to be the dominant market for rare earth elements over the next few years, occupying over two-thirds of the overall demands in 2019.
Click For Report Details @ http://www.radiantinsights.com/research/rare-earth-markets-in-china
