Abstract: A combined heating and conveyor apparatus for use in heating a bulk solid product, such as a food product, comprises a hollow channel member having a base that forms a conveying surface along which product is to be moved, the channel member having at least one entrance region and one discharge region, an actuator which in use causes the channel member to vibrate in a manner which tends to cause product introduced to the channel at the entrance region to move towards the discharge region; and characterised in that the channel member functions as a microwave frequency closed waveguide, and a source of microwave radiation is connected to the channel member in such a way that the microwave radiation propagates along the channel member and is substantially retained within the channel member whereby, in use, the energy in the microwaves can be at least partially absorbed by the product that passes along the channel.