Inorganic chemicals

Solvay Chemicals also produces sodium metabisulfite by reacting sodium carbonate with sulfur dioxide. The plant in Green River, Wyoming began production in April 1997 and has a capacity of 12,000 tons per year. Production of sodium metabisulfite begins with the burning of sulfur to produce sulfur dioxide gas, SO2. Excess SO2 gas is reacted with sodium carbonate liquor in the absorber-contactor, and the resulting metabisulfite solution is sent to a crystallizer. Sodium metabisulfite crystals are formed in the crystallizer, and then dried with heated air. The resulting sodium metabisulfite product is pneumatically transported to one of four storage silos for bagging. The product is bagged in 25-kilogram, 50-pound, 100-pound, and 2000-pound super sacks in a state-of-the-art bagging facility.

Solvay Chemicals produces three grades of sodium metabisulfite: Technical, Food and Photographic. Its product is certified kosher.