A system and method of direct reduction of iron (DRI) is disclosed, having a reduction unit configured to reduce iron oxides to metallic iron; a process gas heater coupled to the reduction unit, the process gas heater configured to supply the reduction unit directly with a source of heated reducing gas, where the process gas heater is further configured to receive a synthetic combustion air stream for heating the reducing gas, the synthetic combustion air stream comprising a source of oxygen with essentially no nitrogen. A method of carbon dioxide emission reduction from a direct reduction of iron (DRI) process is also disclosed.

Provision of a gas production apparatus that can stably produce a product gas with carbon monoxide as its main component from a separated gas including carbon dioxide as a main component.

The gas production apparatus 1 consists of the following: a separation and capture section 5, which separates and captures separated gas containing mainly of carbon dioxide from the exhaust gas taken from the line of the exhaust gas equipment; a reaction section 4 including at least a reactor, which is connected to downstream of the separation and capture section 5, contains a reducing agent that generates carbon monoxide through a reduction reaction of carbon dioxide brought into contact with the separated gas, and is capable of separating at least some of oxygen atoms separated from carbon dioxide; a pressure regulating section 7 connected to downstream of the reactor 4 to regulate the pressure of the separated gas supplied to the reactor; and the flow regulating section 6 connected on the upstream of the separation and capture section 5 and regulates the flow rate of the separated gas supplied to the reactor.

A method and apparatus for producing direct reduced iron using a pre-treated make-up gas as a reducing agent in a direct reduced iron reactor are provided. The method involves pre-treating a stream of make-up gas containing heavy hydrocarbons by subjecting the stream to low temperature adiabatic reforming at a temperature between 300° C. and 600° C., prior to using the stream of make-up gas as a reducing agent for producing direct reduced iron. The method also involves adjusting the humidity content of the stream of make-up gas after the low temperature adiabatic reforming by bypassing the stream to selectively split it into a first part of the stream of make-up gas and a second part of the stream of make-up gas, subjecting the first part to water separation, and then mixing the first part with the second part to obtain a reducing stream to be sent to direct reduced iron production.

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.

A method and apparatus for producing direct reduced iron (DRI), including: generating a reducing gas in a coal gasifier using coal, oxygen, steam, and a first coke oven gas (COG) stream as inputs to the coal gasifier; and delivering the reducing gas to a shaft furnace and exposing iron ore agglomerates to the reducing gas to form metallic iron agglomerates. The method further includes delivering a second COG stream directly to the shaft furnace.

A method and apparatus for producing direct reduced iron using a pre-treated make-up gas as a reducing agent in a direct reduced iron reactor are provided. The method involves pre-treating a stream of make-up gas containing heavy hydrocarbons by subjecting the stream to low temperature adiabatic reforming at a temperature between 300 C. and 600 C., prior to using the stream of make-up gas as a reducing agent for producing direct reduced iron. The method also involves adjusting the humidity content of the stream of make-up gas after the low temperature adiabatic reforming by bypassing the stream to selectively split it into a first part of the stream of make-up gas and a second part of the stream of make-up gas, subjecting the first part to water separation, and then mixing the first part with the second part to obtain a reducing stream to be sent to direct reduced iron production.

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.

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).

Methods and systems for producing direct reduced iron having increased carbon content, comprising: providing a reformed gas stream from a reformer; delivering the reformed gas stream to a carbon monoxide recovery unit to form a carbon monoxide-rich gas stream and a hydrogen-rich gas stream; and delivering the carbon-monoxide-rich gas stream to a direct reduction furnace and exposing partially or completely reduced iron oxide to the carbon monoxide-rich gas stream to increase the carbon content of resulting direct reduced iron. The carbon monoxide-rich gas stream is delivered to one of a transition zone and a cooling zone of the direct reduction furnace. Optionally, the method further comprises mixing the carbon monoxide-rich gas stream with a hydrocarbon-rich gas stream.

A method for treating desulfurization slag involves conveying desulfurization slag from pig iron desulfurization to a unit where the desulfurization slag is melted at a temperature of at least 1,400 C. In the unit, a thorough mixing is achieved. The treatment takes place in the unit under oxidizing conditions. Sulfur dioxide is generated and collected from the roasting gas and supplied for further utilization.