Suspension-firing of biomass for heat and power generation: Development of biomass preparation for resolving the critical firing issues

Biomass is the largest renewable energy source. Currently, direct burning of biomass for heat and power generation is the most common and cost-effective routine to turn biomass into energy, in which suspension-firing is most widely used. Biomass requires much more care in handling than coal, particularly for suspension-firing which has the highest requirement on fuel quality and fuel particle size among all combustion technologies. This paper reviews the development of biomass preparation for suspension-firing, which directly affects fuel particle sizes and thus particle flow, particle burnout and ash usability. Another critical issue in biomass suspension-firing, i.e., deposition and corrosion, is also presented. All the discussion is combined with concrete examples of biomass dust-firing in power plants and their pros and cons, facilitating the understanding of the key issues and also providing good models or references for other biomass dust-fired power plants.