Welcome to ClearStack!

ClearStack Combustion Corporation was formed and incorporated in the State of Illinois in June of 1998. The company mission statement is:

“To develop and implement pollution control technologies for the continued use of fossil fuels, especially coal, at the lowest cost in the marketplace.”

The ClearStack technologies are low cost pollutant reduction systems and the technologies have all been patented. ClearStack currently has three technologies that are ready or near ready for commericalization:

The Ashworth Gasification-Combustion System™ (AG-CS™) is a low cost, but very effective, multi-pollutant reduction technology that ClearStack has targeted for its first marketing efforts. The system will reduce NOx emissions down to < 0.10 lb/million Btu of coal fired, particulate entering the boiler by 65%, SO2 by 70+%, Hg by 90+% and other air metal toxics by 80-90+%. Limestone is added to capture sulfur, mercury, and other heavy metal air toxics in the slag produced. The limestone also captures some chlorine and fluorine. Further, up to 20% biomass can be fired with coal to reduce carbon dioxide emissions.

The Stage3Cyclone™ is a three-stage gasification-combustion technique for cyclone boilers. It uses three stages of oxidation, the third of which is overfire air (OFA). Limestone is added with the coal to maintain good slag fluidity. This staged combustion technique will effectively reduce NOX emissions from cyclone units at very low capital and operating costs, offering the performance of Selective Catalytic Reduction (SCR) at a substantially reduced cost. This simple three-stage oxidation technique, like the AG-CS will reduce NOX emissions to less than 0.15 lb /106 Btu.

The ClearGas™ dry scrubber technique uses potassium hydroxide (KOH) to remove sulfur oxides and nitrogen oxides from flue gases. It removes sulfur trioxide (SO3) that will reduce flue gas opacity. The presence of potassium salts on a downstream electrostatic precipitator (ESP) increases the “spark over” voltage and improves ESP performance even though SO3, a fly ash conditioning agent, is removed in the process.