7. Energy

An assessment of the energy content for the production of Ta/Nb integrates all the stages of their production [36] :

• mining ;

• concentration (grinding, magnetic and gravimetric sorting, flotation);

• chemistry (etching and separation) ;

• reduction (aluminothermic or sodiothermic) ;

• refining (electron bombardment furnace).

Energy content calculations are based on pyrochlore for ferroniobium, and niobium and tantalum metal from ore, excluding pyrochlore (table 7...