Potential direct use of solid biomass in internal combustion engines

The direct use of dry biomass dust as a fuel in reciprocating engines could be of great interest because of the large availability of plant matter and the versatility of Internal Combustion Engines (ICE). Coal dust was used in the past and mostly in slurries because of large production during industrial era in Europe but led to many problems caused by fuel handling and wear in ICE. In comparison, biomass has a CO2 neutral impact, and is almost ash and sulphur free. Biomass pulverization technologies are now mature and the raw material can be reduced to micronic size or even smaller. Among the various new and renewable fuels under research and development, solid raw biomass is certainly the most promising advanced biofuel. It requires no or little thermochemical or biological processing or upgrading and potentially does not generate waste, detrimental to the environment. After a general overview of the past attempts to run reciprocating engines with coal dust, this paper will assess the so far unconsidered use of dry biomass dust as a fuel in engines instead of abrasive, less volatile and more polluting coal dust.