Coal can be fed into the bed and as it burns it resembles molten lava. If the gas velocity becomes too high, then the particles are entrained in the gas stream and are lost. A fluidized bed behaves like a liquid, so both the bed level and temperature can be easily controlled.
Ang coal ay pwedeng ilagay sa palaparan. Habang ito'y nasusunog, ito ay nagmumukhang “molten lava” o kumukulong bato. Kung ang takbo ng gas ay masyadong mabilis, ang alikabok ay nasasama sa daloy ng gas at nawawala.