This paper contributes to the discussion of how different kinds of industrial scale dryers for biomass influence the
quality properties of wood pellets. It also discusses how the drying technique can affect the environment. The most
common biomass drying processes in use, i.e., convection dryers are discussed. The discussion of drying techniques is
based on advantages and disadvantages with a focus on the drying medium, temperature and residence time. The choice
of drying technique is particularly important if the end-user’s choice of pellets is made due to the specific requirements
for the heating system used. Some specific parameters were tested in order to investigate how the choice of drying
technique affects the pellet quality. The parameters tested were moisture content and the emissions of volatile
hydrocarbons. Pellets available on the market were chosen for the tests. The amount of volatile hydrocarbons left in
sawdust after drying vary with drying technique, as emissions of terpenes are larger in dryers with long residence times.
Low emissions of volatile hydrocarbons would improve the energy content of the sawdust, and by decreasing air
pollution improve the work environment and the environment in the surroundings of the dryers.