The invention relates to a control method for a secondary dust removal system in which a pipe network connects an induced draft fan to at least two suction points. The pipe network comprises a controllable exhaust air flap for each suction point, the position of said flap influencing the volumetric flow rate at the suction point. A mathematical model of the pipe network allows the method to energy-efficiently control the exhaust air flaps and the induced draft fan.

The invention relates to a method for reducing metal oxides to metallized material by means of contact with reduction gas, wherein an accumulated top gas is dry dedusted and reformed in a raw gas mixture together with gaseous hydrocarbons. The water vapor content of the dry dedusted top gas designated for the preparation of the raw gas mixture is adjusted in a saturator in the countercurrent by means of saturation water, wherein the temperature of the saturation water is adjusted, by mixing cold water with a hot water having a higher temperature than the cold water, in order to produce the saturation water at a target value. The invention further relates to a device for carrying out such a method, having corresponding conduits.

Disclosed are methods useful in applications relating to blast furnace processes. The methods of the present invention provide enhanced deposition inhibition of particulate matter in top-pressure recovery turbines. The methods of the present invention comprise adding nitrogen-containing compounds to a top-pressure recovery turbine, inhibiting deposition of solids formed from blast furnace gas on top-pressure recovery turbine components.

The invention relates to the use of off-gas from furnaces (2) for the process of reduction of iron oxide. The bypass duct leads off-gas with reduction atmosphere directly into the reactor, passing through and back to join the main duct of dedusting system using negative pressure of the primary dedusting system. The off-gas directly heats up the iron oxide pellet and maintain the reduction atmosphere in the reactor and allow the reaction to proceed and prevent re-oxidation.

A process for operating an oxidizable combustion gas cleaning unit in a metallurgical plant, including the steps of: (a) passing an oxidizable combustion gas from a metallurgical reactor, in particular a blast furnace gas from a blast furnace, in a packed bed scrubber arrangement through a packed bed in countercurrent with a washing water or in a spray scrubber arrangement to remove cyanide compounds, in particular hydrogen cyanide, and to increase the removal of chloride compounds, in particular hydrogen chloride, from the combustion gas by solubilizing the cyanide and chloride compounds in the washing water, (b) collecting the washing water containing solubilized cyanide and chloride compounds at a bottom end of the packed bed or spray scrubber arrangement, and (c) collecting a cleaned oxidizable combustion gas at a top of the packed bed or spray scrubber arrangement, wherein a base is added to the washing water before step (a).

A cooler (1) for cooling hot bulk goods (17) preferably iron ore sinter: The cooler has a grate surface (16) for holding the hot bulk goods (17) to be treated to reduce the dust emissions and at the same time to also enable maintenance measures on the cooler (1). Covers are located in the region of the feed point (2) and the removal point (3). The device herein provides an additional boundary, which prevents the removal of dust particles of size over 150 m. The boundary is a stationary first wall (12) and a stationary second wall (11) and the boundary extends over a partial segment, and preferably over the entire region, of the uncovered grate surface (16). A supporting structure (18) is provided, to which the first wall (11) and the second wall (12) are fastened.

A process and a device for treating a flow of furnace gas with a pressure of more than 1 bar flowing through a channel. A powder agent, such as a powder comprising alkali reagents, such as lime, and/or absorbents, such as activated coal, is injected under an overpressure into the furnace gas flow via an injector which is positioned centrally within the channel. The powder agent may be fluidized. The pressure for injecting the powder may be adjusted by controlling the volume of fluidization gas vented via a venting outlet.

A process for the production of carburized sponge iron, including charging iron ore into a direct reduction shaft, and/or discharging carburized sponge iron from the direct reduction shaft, whereby a seal gas is introduced into the direct reduction shaft; removing a top gas from the direct reduction shaft; recycling a proportion of the top gas and mixing with a make-up gas to form a reducing gas; and introducing the reducing gas into the direct reduction shaft in countercurrent flow to the iron ore in order to reduce the iron ore and produce carburized sponge iron. The seal gas consists essentially of carbon dioxide, and the make-up gas comprises greater than 80 vol % hydrogen gas. Also provided is a system for the production of carburized sponge iron, as well as a carburized sponge iron produced by the aforementioned process.

The invention relates to the production of direct reduced iron, DRI, where a hydrogen direct reduction is synergistically operated in the context of an industrial plant. The hydrogen reduction operates with reducing gas comprising at least 85 vol. % hydrogen, and receives a make-up hydrogen stream. At least part of the make-up hydrogen stream is produced on site. by at least one of (i) electrolysis means configured to produce hydrogen from steam recovered from one or more components of the industrial plant and/or from steam generated using waste heat and/or hot gases emitted by the one or more components; and (ii) gas shift reactor means configured to convert CO-bearing gas emitted by at least one component of the industrial plant into hydrogen and to remove CO.sub.2.

A process for producing solid carbon and gaseous oxygen from CO.sub.2 via electrolysis using an electrolysis apparatus is disclosed. The apparatus includes a chamber with an electrolyte inlet, an electrolyte outlet, a liquid electrolyte containing CO.sub.2 in the chamber, at least one cathode-anode pair, with the cathode including a liquid metal capable of catalysing reduction of CO.sub.2 to solid carbon at a selected operating temperature of the process. The process includes causing the electrolyte to flow from the inlet to the outlet in fluid communication with the cathode-anode pair, applying a voltage between the cathode-anode pair and causing solid carbon to form on the cathode from CO.sub.2 in the electrolyte and gaseous oxygen to be evolved at the anode from CO.sub.2 in the electrolyte.