Biomass Briquettes - Cofiring

Cofiring

Cofiring relates to the combustion of two different types of materials. The process is primarily used to decrease CO₂ emissions despite the resulting lower energy efficiency and higher variable cost. The combination of materials usually contains a high carbon emitting substance such as coal and a lesser CO₂ emitting material such as biomass. Even though CO₂ will still be emitted through the combustion of biomass, the net carbon emitted is nearly negligible. This is due to the fact that the material gathered for the composition of the briquettes are still contained in the carbon cycle whereas fossil fuel combustion releases CO₂ that has been sequestered for millennia. Boilers in power plants are traditionally heated by the combustion of coal, but if cofiring were to be implemented, then the CO₂ emissions would decrease while still maintaining the heat inputted to the boiler. Implementing cofiring would require few modifications to the current characteristics to power plants, as only the fuel for the boiler would be altered. A moderate investment would be required for implementing biomass briquettes into the combustion process.

Cofiring is considered the most cost-efficient means of biomass. A higher combustion rate will occur when cofiring is implemented in a boiler when compared to burning only biomass. The compressed biomass is also much easier to transport since it is more dense, therefore allowing more biomass to be transported per shipment when compared to loose biomass. Some sources agree that a near-term solution for the greenhouse gas emission problem may lie in cofiring.