Electrostatic enrichment of trona and nahcolite ores

A process for beneficiating an ore containing sodium carbonate values in combination with insoluble impurities said ore being selected from the group consisting of trona bearing ore and nahcolite bearing ore to give a product containing a greater percentage of sodium carbonate and a lesser percentage of insoluble impurities than were present in said ore which comprises:

• calcining the ore to provide at least a surface coating of sodium carbonate, separating fines from the calciner off-gases and collecting said fines in a container;
• crushing said calcined ore to a particle size smaller than about 6.7 mm, returning ore particles larger than about 6.7 mm to the crusher, separating the calcined ore particles smaller than about 6.7 mm into a plurality of fractions containing particles of relatively uniform particle size, collecting that sized fraction having a particle size less than about 0.212 mm in a container, passing the other sized fractions through a high voltage gradient thereby effecting a separation of said other sized fractions into an ore concentrate containing a greater percentage of sodium carbonate and a lesser percentage of insoluble impurities than were present in said other sized fractions, and ore tailings containing a lesser percentage of sodium carbonate and a greater percentage of insoluble impurities than were present in said other sized fractions, collecting said ore fraction from each of said other sized fractions in a container, and combining said fines with that sized fraction having a particle size less than about 0.212 mm and said ore concentrate from each of said other sized fractions to produce technical grade of soda ash.