Fried. Krupp Gesellschaft MIT Beschrankter Haftung

Mannesmann Aktiengesellschaft

Fried Krupp

Fried.krupp Gesellschaft

Klaus H Ulrich

Wilhelm Janssen

Dietrich Radke

Thomas Hoster

Hermann Doerr

Dieter Neuschuetz

Lutz Rose

Horst Kappes

Reinhard Herbrig

Wilhem Janssen

Hartmut Vorwerk

A process for producing stainless steels, particularly special steels containing chromium and chromium-nickel, in a smelting arrangement having at least two vessels, for supplying a steel foundry. A charge having mostly iron-containing raw scrap materials and partially carbon-containing alloy carriers is melted in a first vessel. At a temperature of 1460&deg; C., the melt is decarburized by the injection of oxygen so as to reduce the carbon content to less than 0.3%. The melt is heated to a tapping temperature of between 1620&deg; C. to 1720&deg; C. and the carbon content is subsequently reduced to 0.1%. A second charge is melted in a second vessel simultaneously with the decarburizing of the first charge in the first vessel.

Producing stainless steels in parallel operated vessels

A process and device for removing heavy metals and compounds containing heavy metals from waste gas of a metallurgical vessel which is charged with materials posing disposal problems. The flue gas collecting in the metallurgical vessel is sucked out of the vessel as a main gas flow and cleaned in a gas cleaning system. The flow of cleaned gas is guided to an after-burning device. A portion of the clean flue gas is diverted frown the main gas flow leading to the after-burning device. The diverted flow portion is cooled and guided back to the main flow of flue gas where it is mixed with the flue gas before the main flow of flue gas enters the gas cleaning system.

Process and device for removing heavy metals and compounds containing

A process and apparatus for producing ferrochromium having a carbon content ranging from about 0.02 to about 10 weight percent includes providing a mixture comprised of iron-containing chromium ore, coal, and at least one slag former selected from each of a slag former of group (a) and a slag former of group (b), wherein the slag former of group (a) is selected from the group consisting of CaO and MgO, wherein the slag former of group (b) is selected from the group consisting of Al.sub.2 O.sub.3 and SiO.sub.2, and wherein the mixture has an ore or coal ratio ranging from 1:0.4 to 1:2. The mixture is heated in a rotary furnace for a period ranging from 20 to 240 minutes in a CO-containing atmosphere and at a temperature ranging from 1480.degree. to 1580.degree. C. to provide a reaction product. The reaction product is discharged from the rotary furnace in a doughy state and is cooled, either during or after discharging the reaction product from the rotary furnace, by mixing the reaction product with at least one additive effective for heating and decarbonation for a subsequent melting step, which at least one additive is at ambient temperature prior to being admixed, so that the mixture has a reduced temperature and is in a solid state as it is conveyed to a melting furnace. Finally, the mixture is melted in the melting furnace as a temperature ranging from 1600.degree. to 1700.degree. C. to obtain ferrochromium.

Process and apparatus for the production of ferrochromium

Process for the reduction of iron containing chrome ores in which a mixture of chrome ore, coal and slag producers with an ore-coal ratio of 1:0.4 to 1:2 is heated in a rotating furnace in a CO containing atmosphere to temperatures of between 1100.degree. and 1580.degree. C. and in which the rotating furnace is heated in counter flow by a burner through the central nozzle of which oxygen and/or air is supplied. The burner is located at the reaction product discharge end of the furnace and 10 to 90% of the coal for the raw material mixture is introduced into the rotating furnace through the reaction product discharge end, with at least part of this coal being introduced through an outer nozzle of the burner.

Process for the reduction of iron-containing chrome ores

A process for the production of ferrochromium from iron-containing chromium ores, in which the reduction of the ore, which is mixed with coal and slag-forming constituents, is conducted in a rotary kiln at 1480.degree. to 1580.degree. C. in the presence of a CO-containing atmosphere from 20 to 240 minutes, and in which melting follows in a melting furnace at 1600.degree. to 1700.degree. C. By this process, the greatest part of the gangue of the ore can be separated off before melting the reduced ore.

Process for the production of ferrochromium

An apparatus for preheating granular ore includes a shaft defined by vertical walls, an inlet chute disposed above the shaft for introducing the ore thereinto by gravity, an ore discharge collector situated underneath the shaft for receiving preheated ore therefrom, and an arrangement for passing heating gases upwardly in the shaft. The discharge collector has vertical side walls and further, there is provided an insert situated in the discharge collector and extending generally horizontally thereacross. The insert has a downwardly widening configuration. A discharge device is disposed at a lower end of the discharge collector.

Apparatus for preheating granular ore

In a reduction process carried out in a rotary kiln in which oxygen-containing gases are introduced by way of nozzles and at least a part of the highly volatile solid reductants are introduced from the discharge end so as to be distributed over a substantial region of the kiln bed, and any remaining balance of the reductants is fed jointly with the ore and the additives at the feed end, the formation of fusion deposits is prevented by the introduction of at least 60% of the reductants via the discharge end, and that at least a 60% portion of the reductants includes no more than 20% of the total reductant particulates having less than a 3 mm particle size.

Method for reducing oxidic iron ores in a rotary kiln

A process for the production of ferromanganese from iron-containing manganese ores, in which the reduction of the ore, which is mixed with coal and slag-forming constituents, is conducted in a rotary kiln at 1200.degree. to 1350.degree. C. in the presence of a CO-containing atmosphere for 20 to 240 minutes, and in which melting follows in a melting furnace at 1400.degree. to 1600.degree. C. By this process, the greatest part of the gangue of manganese ore can be separated off before melting the reduced ore.

Process for the production of ferromanganese

An apparatus for separating sponge iron products from the hot discharge material of a rotary furnace. A discharge chamber is connected to the rotary furnace for receiving the hot discharge material from the rotary furnace. A screen is provided at the lower end of the discharge chamber for separating the sponge iron products from the hot discharge material. The screen is attached to a support which is removably sealed to the lower end of the discharge chamber and is provided with a mechanism for displacing the support and attached screen. The support includes a discharge chute connected beneath the screen for carrying away the material which passes through the screen and is provided with cooling means.

Growing community of inventors

Heiligenhaus, Germany

Klaus H Ulrich