Wednesday, March 16, 2011

Trona


What is trona?

·         Trona is a naturally occurring mineral that is known chemically as sodium sesquicarbonate.
·         Trona is used primarily to make soda ash (which in turn is used in glass manufacturing, paper, food additives, laundry products, and medicine, to name only a few.)
·         Trona's other uses are air pollution control and animal feed. It is fed to dairy cows as a rumen buffer.
·         Trona is found at Owens Lake and Searless lake, California; Utah and even the Nile valley delta regions in Egypt. The Trona near Green river Wyoming is the chief known deposit in the earth and lies in encrusted evaporate leaves from 800 to 1600 feet below ground, where the Trona was placed in a lake during the paleogene period. Trona has also been excavated at Lake Magadi in the famous rift valley in Kenya for virtually 100 years, and emerges in 'salt' pans in the Etosha National Park in Namibia.
·         Trona (trisodium hydrogendicarbonate dihydrate); Na3H(CO3)2·2H2O is an evaporite mineral. It is mined as the primary source of sodium carbonate in the United States, where it has replaced the Solvay process used in most of the rest of the world for sodium carbonate production.
·         The word "trona" comes to English by way of either Swedish (trona) or Spanish (trona), with both possible sources having the same meaning as in English. Both of these derive from the Arabic trōn which in turn derives from the Arabic natron, and Hebrew נטרן pronounced natruna, which comes from ancient Greek νιτρον, derived ultimately fromancient Egyptian ntry (or nitry).


What are the major markets for trona?
·         Air pollution control: Trona is used by industries as varied as glass, cement, waste incineration, gold and other precious metal refining, petroleum refining, pulp & paper, and electric power generation for air pollution control.
·         Trona effectively removes sulfur oxides (SOx), hydrogen sulfide (H2S), hydrochloric acid (HCl), and hydrofluoric acid (HF) from flue gas emissions.
·         Animal feed: Trona is also used in animal feed, with the largest market being a rumen buffer for dairy cows. A proper feed program that includes trona actually increases milk production.

 Is trona widely used?
·         Trona is used for air pollution control from Alaska to Maryland, from Washington State to Florida.
·         Trona is used throughout North America in animal feed

How does trona work in air pollution control? What air pollutants does trona target?
·         Trona is used in dry sorbent injection systems (DSI) where it reacts with acid gases to form a safe, non-corrosive waste product that will not damage equipment.
·         It removes hydrochloric acid and sodium dioxide and trioxide (SOx)
·         Field-testing has shown removal rates of SOx greater than 90%.
·         It has routinely achieved HCl removal of 95-99%.

When was it determined that trona could be used for air pollution control?
Solvay discovered trona's value as an air pollution control product about 20 years ago in Colorado, where it has been used effectively by a public utility power station in Denver for control of SO2 emissions ever since.

Is it approved by the EPA?
·         The EPA or the appropriate State Regulatory Agencies have approved trona's use as an air pollution control product.

As it is a fine powder, can the use of trona to control air pollutants by itself CAUSE air pollution?
·         When used correctly in DSI systems, trona does not result in further air pollution.
·         It is an effective product with safe, non-corrosive by-products.
·         In many cases, the use of trona improves the discharges from a source because it enhances the performance of an ESP (electrostatic precipitator - used for particulate control)

What is dry sorbent injection (DSI)?
·         Dry sorbent injection is a process where a powdered substance is blown into an air duct containing acid gases. The gases react with the powder to form safe byproducts. The byproducts and any excess powder are removed from the air stream using one of several techniques. The clean air is then discharged into the atmosphere through the exhaust stack.

How else is trona used to combat air pollution besides DSI?
·         Trona is also added in other processes to control pollutants. For example, in production of gold ore, trona is added to the roaster (U.S. Patent #6,270,555) to control sulfur dioxide emissions.
·         Trona is added in cement kilns to control sulfur emissions.

Is trona a harmful mineral?
·         Trona is a non-hazardous, non-flammable mineral.
·         Trona has been used to clean acid gas air streams in power plants and industry for over 20 years.
·         For specific information regarding the safety and environmental properties of trona, 

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