Biomass-coal Fuels Show Promise

LEXINGTON, Ky. (Feb. 24, 2009) – University of Kentucky researchers have found that fuels engineered from biomass and coal fines can be burned to produce energy and fewer emissions without requiring modifications to conventional coal-fired stoker furnaces.

 

The researchers, led by Darrell Taulbee at UK’s Center for Applied Energy Research (CAER), developed briquettes of biomass and coal fines – small coal particles that often are discarded as waste.  The biomass consisted of sawdust, processed sorghum and weeds taken from reclaimed surface mines and fallow fields in Eastern Kentucky. 

 

They test-burned different types of biomass with coals of differing quality and found the engineered fuels reduced nitrogen oxide emissions by as much as 42 percent compared to regular stoker coal fuels, while emissions of sulfur dioxide were reduced by as much as 39 percent.  Even fuels made of lower quality coal fines showed emission reductions of 14 percent for nitrogen oxides and 11 percent for sulfur dioxide.

 

The tests were performed at the East Kentucky Correctional Complex (EKCC) in West Liberty. Taulbee worked with a startup company, KeLa Energy LLC of Orlando, Fla., a firm that has worked with CAER to develop a process that produces fuel pellets from biomass, coal fines and other waste material.  Kela Energy provided two of the four fuels that were tested. 

 

The combining of biomass and coal fines into briquettes and pellets may eliminate obstacles that had prevented the use of both materials to produce energy. Biomass, which accounts for less than 4 percent of total U.S. energy consumption, presented problems because of seasonal availability, low density and the capital investment required to use it.  Coal fines, meanwhile, traditionally have been discarded as waste because of handling, storage and transportation issues.

 

The CAER researchers found that biomass/coal briquettes are amenable to drying without dust problems and can be stored, transported and processed in existing infrastructure.  They also increase the distance that biomass can be economically transported.