Heat treatment of material

A method for the heat treatment of a material in discrete form, the method including the steps of burning a fuel in a fluidised combustion bed contained within a combustor having at least one thermally conductive imperforate wall, arranging a heat treatment bed of the material so as to receive heat through said wall, forming combustion gases from the combustion bed directly into a plurality of spaced streams in which each stream in turn is formed into a plurality of smaller streams released at diverse points across the plan of the heat treatment bed, introducing said smaller streams into the base region of the heat treatment bed downwardly thereby distributing the gases throughout the base region of the heat treatment bed which is fluidised at least partly by said gases, and passing the combustion gases from the combustion bed in heat exchange relation with the heat treatment bed prior to the introduction of the gases into the heat treatment bed.

A method for calcination of gypsum in discrete form, the method including the steps of burning a fuel in a fluidised combustion bed contained with a combustor having at least one thermally conductive imperforate wall, arranging a heat treatment bed of gypsum so as to receive heat through said wall, continuously introducing gypsum to the heat treatment bed, continuously withdrawing calcined gypsum from the heat treatment bed, forming combustion gases from the combustion bed directly into a plurality of spaced streams in which each stream in turn is formed into a plurality of smaller streams released at diverse points across the plan of the heat treatment bed, introducing said smaller streams downwardly into the base region of the heat treatment bed thereby distributing the gases throughout the base region of the heat treatment bed which is fluidised at least partly by said gases, and passing the combustion gases from the combustion bed in heat exchange relation with the heat treatment bed prior to the introduction of the gases into the heat treatment bed.

A method for the calcination of gypsum in discrete form, the method including the steps of burning a solid fuel in a fluidised combustion bed contained within a combustor having at least one thermally conductive imperforate wall providing an extended heat exchange area, arranging a heat treatment bed of gypsum so as to receive heat through said wall, heating the heat treatment bed indirectly through the wall and extended heat exchange area, continuously introducing gypsum to the heat treatment bed, continuously withdrawing calcined gypsum from the heat treatment bed, forming combustion gases from the combustion bed directly into a plurality of spaced streams in which each stream in turn is formed into a plurality of smaller streams released at diverse points across the plan of the heat treatment bed and introducing said smaller streams downwardly into the base of the heat treatment bed thereby distributing the gases throughout the base region of the heat treatment bed which is fluidised at least partly by said gases.

A method for the heat treatment of a material in discrete form, the method including the steps of burning a solid fuel in a fluidised combustion bed contained within a combustor having at least one thermally conductive imperforate wall providing an extended heat exchange area, arranging a heat treatment bed of the material so as to receive heat through the wall and extended heat exchange area, forming combustion gases from the combustion bed directly into a plurality of spaced streams in which each stream in turn is formed into a plurality of smaller streams released at diverse points across the plan of the heat treatment bed, introducing said smaller streams downwardly into the base of the heat treatment bed thereby distributing the gases throughout the base region of the heat treatment bed which is fluidised at least partly by said gases, and passing the combustion gases from the combustion bed in heat exchange relation with the heat treatment bed prior to the introduction of the gases into the heat treatment bed.

A method for the heat treatment of a material in discrete form, a method including the steps of burning a solid fuel in a fluidised combustion bed contained within a combustor having at least one thermally conductive imperforate wall providing an extended heat exchange area, arranging a heat treatment bed of the material so as to receive heat through the wall and extended heat exchange area, forming combustion gases from the combustion bed directly into a plurality of spaced streams in which each stream in turn is formed of a plurality of smaller streams released at diverse points across the plan of the heat treatment bed and introducing said smaller streams downwardly into the base of the heat treatment bed thereby distributing the gases throughout the base region of the heat treatment bed which is fluidised at least partly by said gases.

Apparatus for the heat treatment of a material in a discrete form including a combustor adapted to contain a fluidised combustion bed of particulate material and having at least one imperforate thermally conductive wall for indirect heat exchange therethrough, said wall having protuberances to provide an extended area, a fuel inlet for the combustor, an exhaust gas outlet for the combustor, a heat treatment vessel enclosing at least the said wall to receive heat of combustion transmitted through the extended area thereof, the vessel being adapted to contain a bed of material in discrete form, a material inlet and a material outlet in the vessel, and a plurality of gas distribution means located in and end in the vessel and connected to the exhaust gas outlet, each gas distribution means spaced from another extending into the base region and releasing at diverse points across the plan of the vessel at a horizontal location and having perforations directed downwardly therein near its end.

Apparatus for the heat treatment of a material in discrete form including a horizontally elongate combustor adapted to contain a fluidised combustion bed of particulate material and having at least one horizontally elongate imperforate thermally conductive wall for indirect heat exchange therethrough, a fuel inlet for the combustor, an exhaust gas outlet for the combustor, a heat treatment vessel enclosing at least the said wall to receive heat transmitted therethrough from the combustion, the vessel being adapted to contain a bed of material in discrete form, a material inlet and a material outlet in the vessel, a horizontally extending exhaust gas manifold adjacent the heat treatment vessel and in heat exchange contact therewith, and a plurality of gas distribution means located in and ending in the vessel and connected to the manifold, the gas distribution means extending into and releasing at diverse points across the base region of the vessel at a plurality of horizontally spaced locations and having perforations directed downwardly therein near their ends.

Apparatus for the heat treatment of a material in discrete form including a combustor adapted to contain a fluidised combustion bed of particulate material and having at least one imperforate corrugated thermally conductive wall for indirect heat exchange therethrough, a fuel inlet for the combustor, an exhaust gas outlet for the combustor, a heat treatment vessel enclosing at least the said corrugated wall to receive heat transmitted therethrough from the combustion, the vessel being adapted to contain a bed of material in discrete form, a material inlet and a material outlet in the vessel, and a plurality of downwardly directed perforated gas distribution means extending into the base region releasing at diverse points across the plan of the vessel at a plurality of horizontally spaced locations.