Abstract: Cement clinker is produced in that raw cement powder is preheated in a suspension-type heat exchanger and is de-acidified in a fluidized bed and clinkered in a rotary kiln, and the clinker is subsequently cooled. A de-acidification of at least 95% is effected at a temperature above 850.degree. C. in a circulation system comprising a fluidized bed reactor, a cyclone separator and a recycling duct. The carbonaceous fuel required for the calcining and clinkering processes is fed in an amount of at least 65% (related to the total heat requirement) to the de-acidifying fluidized bed reactor and in an amount of at least 10% (related to the total heat requirement) to the clinkering rotary kiln.The fuel supplied to the de-acidifying fluidizing bed reactor is burnt near stoichiometrically in two stages with fluidizing gas and secondary gas. The ratios of the rates and volumes of fluidizing gas to secondary gas are so selected that a mean suspension density of 100 to 300 kg/m.sup.

Abstract: Cement clinker is produced in that raw cement powder is preheated in a suspension-type heat exchanger and is de-acidified in a precalcining apparatus and clinkered in a fluidized bed and the clinker is subsequently cooled. An de-acidification of at least 95% is effected at a temperature above 85.degree. C. in a circulation system comprising a fluidized bed reactor, a cyclone separator and a recycling duct. The carbonaceous fuel required for the calcining and clinkering processes is fed in an amount of at least 65% (related to the total heat requirement) to the de-acidifying fluidized bed reactor and in an amount of at least 10% (related to the total heat requirement) to the clinkering fluidized bed reactor. The fuel supplied to the fluidizing bed reactor is burnt near stoichiometrically in two stages with fluidizing gas and secondary gas. The ratios of the rates and volumes of fluidizing gas to secondary gas are so selected that a means suspension density of 100 to 300 kg/m.sup.

Abstract: The measurement of temperature and the sampling of a steel bath in a converter are effected using a remotely controlled device comprising a composite probe or two probes for temperature measurement and sampling, the probe being mounted on the end of a measurement rod fixed to the end telescopic element of a telescopic jack which is pivotally mounted on a carriage mounted for movement on a support suspended above the working platform of the converter. The carriage is horizontally movable between a storage position and a position opposite the mouth of the converter and the jack is pivotal in a vertical plane between a vertical storage position and an inclined operative position with the converter. All movements of the jack and carriage are remotely controlled.

Abstract: A suction device for the wet extraction of dust from dust laden gas comprises a centrifugal rotor housed in a casing and rotatable about an axis, and means for projecting a wetting liquid into the rotor adjacent the gas inlet thereto, the rotor being provided with at least two sets of blades, the blades of each set being uniformly arranged in a crown and forming channels with at least one of the sidechecks of the rotor in which gas flows from the center towards the periphery, the leading and trailing edges respectively of the blades of the first set being located closer to the axis of the runner than the leading and trailing edges respectively of the blades of the second set, the leading edges of the blades of the first set being located near to but angularly spaced from the trailing edges of the blades of the second set.

Abstract: A converter for refining a liquid metal bath using simultaneous heating and blowing in comprises a metal vessel internally lined with refractory material, having an upwardly open mouth and having a generally cylindrofrustoconical shape which is a body of revolution about an axis, the vessel being mounted on, and rotatable about, its axis of revolution relative to a pivotable cradle, the vessel having a pouring spout and a set of tuyeres extending through a wall thereof, and a separate frustoconical cap connected to a gas collection hood for surmounting the vessel and provided with an opening through which a heating device can extend into the vessel, the arrangement being such that in the `normal` position of the vessel, for simultaneous blowing in and heating, the axis of revolution of the vessel is at an angle between 35.degree. and 55.degree. to the vertical, the pouring spout is upwardly directed, the tuyeres extend upwardly from the bottom of the vessel and the vessel is surmounted by the cap.

Abstract: A converter for the refinement of liquid metal comprising a generally cylindrical body having closed ends and an opening in the circumference thereof, the body being arranged with its axis horizontal and being rotatable thereabout, a refractory arch with a heating unit movable into one part of the opening in the "normal" position of the body in which the opening is in an upper part thereof, a gas collection system aligned with the other part of the opening in the "normal" position of the body, and blast pipes extending into the body through a lower part of the body in the "normal" position thereof.