Metallgesellschaft Aktiengesellschaft

Aluminum Pechiney

Other

Vereinigte Aluminium-werke Aktiengesellschaft

Deutsche Babcock Aktiengesellschaft

Lafarge Coppee

Creusot-loire Enterprises

Stora Kopparbergs Bergslags Aktiebolag

St. Joe Minerals Corporation

Lothar Reh

Martin Hirsch

Ludolf Plass

Karel Vydra

Philippe Marchessaux

Hans-Werner Schmidt

Bernd Thone

Martin Rahn

Rolf Graf

Hugo Grimm

Karl-Heinz Dorr

Hans Beisswenger

Hans Werner Schmidt

Sune N Flink

Albert Folliot

Wolfram Schnabel

Harry Serbent

Roland Thome

Carl Hafke

Per H Collin

Bjorn Widell

Per Harald Collin

Gerhard Baron

Harald Sauer

Gunter Winkhaus

Georg Daradimos

Volker Sparwald

Dieter Moritz

Eberhard Blaum

Raman Sood

Carl-August Maelzer

David Rice

Ernst Weckesser

Jorg Thomas

Eberhard Bohm

Maurice P Iard

Kurt Meyer

Maurice Paliard

Michael Schroter

Harry Edward Cross

Wolfgang Krieger

Eberhard Anschutz

Gunter Schoene

Disclosed is a process of carrying out a combined gas turbine and steam turbine process of increased efficiency. A fuel gas is produced at a temperature of from 900.degree. to 1100.degree. C. in a circulating fluidized bed by a gasification of 70 to 95 wt. % of the carbon contained in the carbonaceous material and is treated at a temperature of from 850.degree. to 950.degree. C. with suspended solids consisting of calcium hydroxide, calcium oxide and/or calcium carbonate-containing solids to remove pollutants. The main portion of the fuel gas is burnt to produce a gas which is used to operate the gas turbine and which contains at least 5% by volume oxygen and is at a temperature of at least 1000.degree. C. Combustion of the carbonaceous gasification residue to produce process steam is performed in a second circulating fluidized bed at a temperature of from 800.degree. to 950.degree. C. under near-stoichiometric conditions by a treatment with oxygen-containing gases, which are supplied on different levels in at least two partial streams and mainly consist of exhaust gas from the gas turbine. The desulfurized fuel gas is preferably cooled to a temperature in the range from 350.degree. to 600.degree. C. and is freed from halides.

Combined gas and steam turbine process

In a process of removing pollutants consisting substantially of sulfur oxides from exhaust gases at temperatures below 150.degree. C. by means of a sorbent which contains calcium carbonate, calcium oxide and/or calcium hydroxide and which is included in a circulating fluidized bed system consisting of a fluidized bed reactor, a separator and a return line, a complete utilization of the sorbent is achieved in that a partial stream of laden sorbent is withdrawn from the circulating fluidized bed and is subjected at a temperature of 600.degree. to 1200.degree. C. to an oxidizing treatment, a major part of the sorbent that has been subjected to an oxidizing treatment is recycled to the circulating fluidized bed, and a partial stream which contains the sorbent mainly in the form of calcium sulfate is removed from the process. Fresh sorbent is supplied to the circulating fluidized bed and/or to the stage for the oxidizing treatment at the rate at which said partial stream is removed from the process.

Process of removing pollutants from exhaust gases

Fine-grained material which contains iron oxide is prereduced in a fluidized bed and is subsequently completely reduced in a rotary kiln. In order to avoid agglomeration and incrustation in the rotary kiln, the prereduction is carried out to effect a metallization of 50 to 80%.

Process of producing sponge iron by a direct reduction of iron

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.3 is maintained in the zone between the inlet for fluidizing gas and the inlet for secondary gas, and a mean suspension density of 5 to 30 kg/m.sup.3 is maintained above the inlet for secondary gas.

Method of producing cement clinker

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.3 is maintained in the zone between the inlet for fluidizing gas and the inlet for fluidizing gas, and a mean suspension density of 5 to 30 kg/m.sup.3 is maintained above the inlet for secondary gas.

Process of producing cement clinker

A process of gasifying fine-grained solid fuels for the production of a product gas that contains hydrogen, carbon oxides and methane comprises a treatment with steam, oxygen and/or carbon dioxide in two interconnected gasifying stages under a pressure in the range from 2 to 150 bars and at temperatures of 500.degree. to 1500.degree. C. In the first gasifying stage, the fuel is gasified in a circulating fluidized bed by a treatment with gasifying stage. The residual solids which become available in the first gasifying stage are fed to the second gasifying stage and are virtually completely gasified therein, except for residual ash, by a treatment with a gasifying agent which includes oxygen. At least one-half of the product gas from the second gasifying stage is fed to the first gasifying stage and used as fluidizing fluid therein.

Process of gasifying fine-grained solid fuels

A method of recovering fluorine, e.g. as hydrogen fluoride, from wastes of aluminum electrolysis furnaces, chemisorbents, adsorbents or absorbents, etc. in which the fluorine-containing material is subjected to pyrohydrolysis in an expanded fluid bed and the HF-containing gas is subjected to condensation or scrubbing for the removal of the HF therefrom. According to the invention, the exhaust gases from the fluidized bed are cooled by direct contact with solids which can be circulated in a separate cycle and are themselves cooled in a cooler, e.g. by contact with gas which is to be fed to the expanded fluidized bed. The circulated solids thus allow recovery of the sensible heat of the gas without diluting it.

Process for producing hydrogen fluoride

The invention provides a process for thermally decomposing salts, containing mainly ferrous sulfate wherein said feed material is contacted in a single suspension-type exchanger with exhaust gases formed by reaction of the oxygen-containing gases in the fluidized bed reactor, the fluidizing gas and at least a partial stream of the secondary gas stream are heated by an indirect heat exchange in a fuel-heated heat exchanger, and the quantity of oxygen introduced via which consists of the fluidizing gas and the secondary gas, is controlled in dependence on the quantity of fuel in order to receive an exhaust gas from the suspension-type exchanger with a free oxygen content of 1-6% by volume and a temperature of 300.degree.-450.degree. C.

Process for obtaining metal oxide and SO.sub.2 -containing gases

Thermally splitting hydrate of aluminum chloride to produce aluminum oxide wherein the hydrate is at least partially split by contact with hot gases and hot calcined product in a turbulent zone, transmitting the material from the turbulent zone into a residence zone, recycling a portion of the solids from the residence zone to the turbulent zone in an amount to maintain a desired suspension density while the remainder is passed to a turbulent cooling zone in heat exchange with the fluidizing gas introduced into the turbulent zone.

Method of thermally splitting hydrate of aluminum chloride

Zinc and, if desired, lead are volatilized from a metallurgical material such as a finely divided oxidic ore, ore concentrate or another metallurgical intermediate. The volatilization of the zinc is carried out at a temperature above 1300.degree. C. in a cyclone chamber which has an axis that is substantially horizontal, i.e. is inclined to the horizontal at an angle of 0.degree. to 15.degree.. Carbon dioxide is removed from the gas leaving the zinc condensing stage and the high carbon monoxide gas thus obtained is recycled to the cyclone chamber or at another point ahead of the condensation stage.

Process for the volatilization of zinc and/or lead from metallurgical

Carbonaceous material, preferably coal or like finely divided solids with a mean particle diameter of 30 to 250 microns, is burned to produce steam in a fluid-bed furnace having a lower free space without internal fixtures and provided above this free space with internal cooling surfaces. A secondary-gas inlet introduces the secondary gas so that the volume ratio of fluidizing gas to secondary gas ranges from 1:20 to 2:1 at a location above the fluidizing-gas and fuel inlets but below the internal cooling surfaces, the gas velocity of the several gases being adjusted so that the mean suspension density of the solids above the secondary-gas inlet is 15 to 100 kg/m.sup.3. Approximately stoidiometric conditions are maintained with respect to the oxygen in the gases introduced and the carbonaceous material and solids are recycled to the bed after being separated from the gases emanating therefrom.

Process for burning carbonaceous materials

A process for thermally treating fine-grained solids with high-oxygen gases at temperatures at which the solids can form molten and gaseous reaction products comprises carrying out the thermal treatment in a cyclone chamber and thereafter conducting the gases from the cyclone chamber into a horizontal or vertical cooling chamber. The process can be used for the roasting of sulfide ores, ore concentrates and other metallurgical intermediate products. The outlet of the cyclone chamber through which the gases are removed lies approximately along the axis and cooling is carried out in the cooling chamber such that the molten droplets contained in the gas stream entering the latter are cooled in free flight below their solidification point in the gas, i.e., do not contact the walls of the cooling chamber until they are solidified at least along their surfaces.

Process for thermally treating solids with high-oxygen gases, especially

A method of and apparatus for carrying out an exothermic process in which a combustible-containing solid (e.g. coal shale, pyrite or limestone in combination with fuel oil) are burned in a fluidized-bed reactor with primary and secondary streams of oxygen-containing combustion-sustaining gas (in a volume ratio of 1:20 to 2:1) supplied at different levels so that the primary gas acts as the fluidizing gas. The gas velocities and rate of gas feeds are controlled to provide a mean suspension density above the secondary gas inlet of 10 to 40 kg/m.sup.3. The major portion of solid feed is introduced into the space below the secondary gas inlet which is maintained substantially free of internal fixtures and the effluent gases are separated from the entrained solids which are recycled to the bed. Solids withdrawn from the bed are cooled in a fluidized-bed cooler and the temperature of the bed is maintained constant by the controlled recirculation of cooled solids thereto from the cooler. The gas heated in the cooler is fed to the bed as the secondary gas.

Method of and apparatus for carrying out an exothermic process

A process for thermally treating fine-grained solids with high-oxygen gases at temperatures at which the solids can form molten and gaseous reaction products comprises carrying out the thermal treatment at least in part in a cyclone chamber. The solids, high-oxygen gases and, if desired, an energy carrier (usually a carbon-containing solid, liquid or gas) are mixed to form a suspension at a temperature below the reaction temperature. The suspension is fed to a vertical combustion path (tube) and reacts therein to form another suspension of primarily molten particles which is admitted to the cyclone chamber. Reactants are added to the gas phase within a core-flow region of the cyclone chamber and/or immediately after the discharge of gas therefrom to a cooling chamber.

Process for thermally treating fine-grained solids

The thermal decomposition of aluminum chloride hydrate in which the preponderant portion of the hydrate is thermally decomposed in an indirectly heated reaction chamber while in a fluidized state with any remainder thermally decomposed in a directly heated rotary furnace and passing the formed aluminum oxide in heat exchange with combustion gases to cool the aluminum oxide and to preheat the combustion gases.

Process for the thermal decomposition of aluminum chloride hexahydrate

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Frankfurt am Main, Germany

Lothar Reh