Microwave torrefaction of biomass

1. A processor for use in the microwave torrefaction of biomass material which comprises:

(i) a material densifier to compress the biomass and preheat the biomass material;

(ii) a microwave unit adapted to conduct microwave-assisted torrefaction of biomass material, the unit comprising a feed pipe for transfer of the biomass material comprising gas and/or liquid outlets to enable rapid removal of gas and/or liquid formed during torrefaction,

wherein the material densifier is integral with the microwave unit for preheating the biomass material entering the microwave unit.

2. A processor according to claim 1 wherein the material densifier is arranged and configured to produce continuous rods of material.

3. A processor according to claim 1 wherein the processor further comprises a carrier tube arranged and configured for feeding densified biomass material directly into and through the microwave chamber.

4. A processor according to claim 1 wherein the microwave unit further comprises a chamber which comprises:

a feed pipe; wherein the feed pipe is arranged and configured such that there is minimum void between the biomass material and an inner wall of the feed pipe and wherein the feed pipe is fitted with one or more gas and/or liquid outlets.

5. The processor of claim 1 , wherein the preheating of the biomass material by the densifier is a result of mechanical friction and compression.

6. A processor for use in the microwave torrefaction of biomass material which comprises:

a microwave unit adapted to conduct microwave-assisted torrefaction of biomass material, the unit comprising:

a feed pipe for transfer of the biomass material comprising gas and/or liquid outlets to enable rapid removal of gas and/or liquid formed during torrefaction; and

a material densifier integral with the microwave unit to compress the biomass and preheat the biomass material entering the microwave unit.