The CoalSwitch fuel was produced from the waste wood residuals at AEG’s facility in Ashland, Maine, and was delivered to Utah to undergo the first phase of the extensive testing programme in the second quarter of 2021. CoalSwitch was produced using AEG’s proprietary steam beneficiation process.
The main focus of this phase of testing was to evaluate the burning and material handling properties of CoalSwitch. The fuel was tested through a bowl mill, which operates at approximately 1 ton per hour, and subsequently tested in a pulverised coal research furnace, operating at 1.3 MW of thermal output. The furnace has a firing system and operational representation of full-scale utility boilers.
It was tested over one week both on its own as well as blended with Utah bituminous coal at various ratios. CoalSwitch and coal were milled, with the milled fuel blends subsequently used for combustion testing.
Key findings from the report on the testing showed:
- The use of CoalSwitch reduced ash by up to 77% compared to coal;
- CoalSwitch reduced nitrogen oxide emissions by 20% compared to coal (when used on its own);
- CoalSwitch reduced sulphur dioxide emissions by 60% compared to coal;
- CoalSwitch has 12.9% higher heating value than white pellets – observed heating value of 9,313 BTU/lb during testing (12.9% premium compared to white pellets currently produced for the market by AEG’s competitors);
- CoalSwitch can be milled using existing equipment while reducing energy use;
- CoalSwitch does not significantly decrease the heating value of coal when blended – with a mix of 75% coal and 25% CoalSwitch, the heating value was 11,807 BTU/lb, representing a 7% drop from normal coal-burning values.
“The testing confirms that CoalSwitch continues to show its superior qualities over coal and white pellets, including its hydrophobic properties, burning at higher heating values than pellets and reducing ash, nitrogen oxide and sulphur dioxide emissions compared to coal,” said Michael Rowan, CEO of AEG.
“Our clean energy pellet offers a new pathway for heavy, hard-to-decarbonise industries which are increasingly pressured to reduce emissions and pollution. CoalSwitch provides a unique ability to achieve these goals without requiring costly, complex and yet-to-be-proven mitigation technologies like carbon capture.
“Customers can ‘drop-in’ our CoalSwitch fuel and see immediate and meaningful reductions in emissions and air pollution.”
Testing was conducted in Utah by Brigham Young University, Rocky Mountain Power (a subsidiary of PacifiCorp), the University of Utah, Chalmers University of Technology and Reaction Engineering International.
The programme was funded independently through Rocky Mountain Power’s Sustainable Transportation and Energy Plan (STEP). The STEP plan decided to test the fuel through the coal-fired research furnace and the programme was completed in Q4 2021.