Abstract: The device has an opening provided through a side wall of the fluidization enclosure and a tube extends outside a enclosure and substantially perpendicular thereto. A duct is connected substantially perpendicularly to the tube and extends downwards. A piston is slidably mounted in sealed manner inside the tube to slide between a first position in which it constitutes a panel closing the opening and a second position in which it at least partially uncovers the opening of the duct into the tube, and control means for controlling displacement of the piston inside the tube.

Abstract: In a fluidized bed there is immersed an internal heat-exchanger connected to a heat-transfer fluid discharge line which feeds an external heat-exchanger fitted in a fluidizing gas delivery line with a by-pass line connected to a flow-control valve so that the heat withdrawn from the fluidized bed and not used is reintroduced therein by means of the fluidizing gas.

Abstract: A fluidized bed heat generator with improved collector for ash removal and heat recovery comprises a central hearth having a fluidization grid at its lower end. The side wall of the hearth is enclosed by a hollow peripheral enclosure to define an intermediate volume therebetween which is connected both to the upper part of the hearth and to fume tubes. These fume tubes extend through the peripheral enclosure and open into a fume exit conduit such that fumes and entrained ash from the hearth can be directed via the intermediate volume and the fume tubes to the fume exit conduit. Water is arranged to circulate within the peripheral enclosure around the hearth and fume tubes.