Trona can be mined primarily through two methods: mechanically and through Solution mining. Mechanical mining uses a bore miner that removes the trona ore from the ground and sends it to the surface using conveyor belts and bucket elevators. Solution mining is achieved by pumping water into the trona ore, dissolving it to create a solution, and pumping it again to the surface.
Once on the surface, the raw trona is converted into usable soda ash via a multi-step purification process:
- The trona ore is precision crushed and screened.
- The sized trona ore is heated in calciners to eliminate unwanted gases and transform it into crude sodium carbonate.
- Water is added, to dissolve the crude sodium carbonate, and the resulting solution is filtered for purification.
- The water is evaporated out, leaving a soda ash crystal slurry.
- The slurry is centrifuged to separate any remaining water from the soda ash crystals.
- These soda ash crystals are dried in rotary driers before being sent to storage bins, ready for shipment.
- Solution mining surface process starts in the fourth step outlined above.