Fluidized bed compact boiler

Compact fluidized bed boiler having at its lower part a combustion chamber (1) which communicates with an enclosure (2) forming, in succession, an exchange chamber (3) containing water tubes (6, 7), an exchange and dust removal chamber (4), and a terminal exchange chamber (5), said exchange and dust removal chamber being divided into first and second half chambers (43, 44) communicating at their lower parts by a vertical internal partition (42), said first half chamber (43) communicating with said exchange chamber (3) through an inlet orifice (46) located laterally relative to said internal partition (42) and facing a wall (41) so that fumes enter substantially parallel to said partition (42) and are stopped by said wall (41) so as to change direction and to be de-dusted, said second half chamber (44) communicating with said terminal exchange chamber (5) through an outlet orifice (47) located laterally relative to said internal partition (42) and opposite said inlet orifice (46) so as to cause a further change of direction of said fumes as well as supplementary de-dusting.