SOLVAir® Select 200 trona For Removal Of HCl, SO₂ and SO₃

SOLVAir Select 200 trona (a natural form of sodium sesquicarbonate) offers a high-assay, low-cost alternative to acid neutralization. When Select 200 trona is used as a dry sorbent injected into an exhaust duct, the trona readily reacts with acid gases to form a safe, non-corrosive waste product that will not damage equipment. Select 200 trona removes HCl, SO2 and SO3 at higher rates than lime and costs less than sodium bicarbonate. Field-testing has shown removal rates of SO2 and SO3 greater than 90%. It has routinely achieved HCl removal of 95-99%.

Why is SOLVAir Select 200 trona so effective? It is a very fine powder and when injected into ducts at temperatures above 250oF (121oC), Select 200 trona rapidly converts to sodium carbonate in a process called “The Popcorn Effect”. The rapid conversion causes a tremendous increase in surface area, similar to the change a kernel of corn undergoes when it is popped. The high surface area and small particle size make the Select 200 trona very reactive and these activated particles rapidly react with acid gases.

Its advantages include:

• Simple systems to design and operate
• Low capital and operating costs
• Meets most emission limit values for acids
• Safe reagent and byproducts
• Can improve ESP removal efficiency
• Non-corrosive to equipment
• No liquid effluent

In recent years, federal and state regulatory agencies have tightened air emission standards. Two of the acid gases, hydrochloric acid (HCl) and sulfur oxides (SO2 and SO3 or SOx), are under heavy scrutiny for reduction. Most traditional scrubbing systems, i.e., wet scrubbers and spray dryers, meet the standards, but they typically are high in capital cost, have significant space requirements for equipment, and are difficult to maintain. Dry sorbent injection (DSI) is an alternative technology that has been shown to be effective in HCl, SO2 and SO3 removal, without the drawbacks of traditional systems.

Dry sorbent injection (DSI) using sodium sorbent is a low-cost alternative to a spray dry or wet scrubbing system for the removal of hydrochloric acid (HCl) and sulfur dioxide (SO2). The process requires no slurry equipment or reactor vessel because the sorbent is stored and injected dry into the flue duct where it reacts with the acid gas. The spent sorbent is collected dry, either through a baghouse or electrostatic precipitator (ESP). It also can be collected through an existing wet scrubber vessel should DSI be used for trim scrubbing of acid mist, as is often the case when scrubbing SO3.

Industries that are already using SOLVAir Select 200 trona for acid gas abatement include pulp & paper mills, utilities, cement, mining, glass furnaces, battery reclamation, municipal and medical waste incinerators, chemical plants, and secondary metal smelters.

SOLVAir Select 200 trona is classified as non-hazardous, and the neutral salt byproducts of the reaction are generally non-hazardous and easily disposed. It is available in bulk railcars, bulk trucks from terminals and our plant in Green River, Wyoming. It is also available in super sacks from our Green River site.