Lime plays two important roles in the production of soda ash and sodium hydroxide.
One of the major sources of soda ash (NA2 CO3) and caustic soda (NaOH) in North America is the refining of naturally occurring trona ores. These naturally occurring ores are mixtures of carbonates, bicarbonates and impurities that have to be refined to produce marketable products. In the production of soda ash from trona, reacting the bicarbonate containing liquid with lime is one of the processes used to convert the bicarbonates in the trona to the carbonate form.
By increasing the lime dosage either the trona or soda ash can be converted to caustic soda, a higher value product. In this process, lime is first slaked and converted to calcium hydroxide (Ca(OH)2). Next the lime slurry is combined with soda ash (Ca(OH)2) + Na2CO3). This yields caustic soda and limestone (2NaOH + CaCO3). The limestone from this reaction can be recycled to make lime.
Soda and caustic soda solution are essential ingredients in an array of industrial operations, including pulp and paper, glass manufacture, water treatment, flue glass tratment, soap and detergents, bleach, petroleum products and alumina, along with many other uses in the chemical processing industry.
Graymont has a number of customers in Wyoming who produce sodium products from trona, and supports them with remote terminals which optimize the cost and reliability of product transportation in remote areas.