Did you know that every time you bite into a cookie, pretzel, sandwich or other baked good, you are eating a rock?
While they may not look like a rock and hopefully don’t taste like a rock, a main ingredient in baked goods such as breads and cakes comes from the ground. You may not be eating an actual rock, but you are eating a mineral that is found in rock.
Most people know trona as the mineral used to make baking soda, but trona – which is the primary source of sodium carbonate – is used for so much more than leavening bread. Half of the world’s trona consumption comes in the form of glassmaking, with the chemical industry using a quarter of the remaining amount.
Trona has been used since the 1st century for making glass, bread, medicine and more. It is used in manufacturing, for water treatment and as an ingredient in toothpaste, textiles, paper, soap and laundry detergent. It can be used to control air pollution because it absorbs harmful gases like sulfur dioxide, as well as to suppress fires since it can smother the flames. Its ability to tabletize makes it an ideal fizzy ingredient in medicines and cleaning products.
But what is trona, and where does it come from?
Trona, from the Arabic word “natron” meaning native salt, is an water-soluble mineral found mainly in the United States. In fact, the world’s largest trona deposit is located in the Green River area of Wyoming, where a 15,000 square mile lake once covered the land more than 50 million years ago. When the water evaporated, it left behind a 100 billion ton trona deposit between layers of sandstone and shale that will supply the world’s trona needs for thousands of years.
Other notable deposits of trona can be found in California, Botswana, Egypt, Kenya, Namibia, Turkey and China.
Trona is mined underground through either the “room and pillar” method or longwall mining and brought to the surface for processing into soda ash. The ore is crushed using machines like DDC-Sizers and Roll Crushers and screened with Vibratory Screens. It is then heated to transform the trona into sodium carbonate. Water is added, then evaporated, and the remaining slurry is sent through a Hydrocyclone or centrifuge to remove any additional water from the soda ash crystals. The crystals are then dried, screened and stored for transport, where they will be put to use in various industries.