In entrained-flow reactors, free-falling particles are entrained downwards by a gas flow. For gasification, entrained-flow reactors are a promising technology as demon­strated in 2002-2003 by Shell and BTG with woody biomass as feedstock [58]. Preliminary tests for biomass pyrolysis applications have shown very high non­condensable yields [59]. It is believed that the geometry of this type of reactor technology promotes important bio-oil thermal cracking. Since the purpose ofpyroly — sis for biorefineries is to produce higher molecular-weight chemicals, this technology will not be covered.