US 2024/0279759 A1 · HYDROGEN GAS RECYCLING IN A DIRECT REDUCTION PROCESS

Abstract

A system for the production of sponge iron, the system including a direct reduction shaft including a first inlet for introduction of iron ore into the shaft, a first outlet for removing sponge iron from the shaft, a reduction gas source, connected through a gas line with the shaft, a first compressor in said gas line, and a primary circuit for conducting at least a part of the top gas therethrough. The primary circuit is connected in one end with shaft and in another end with said gas line downstream said first compressor. The system also includes a secondary circuit for conducting at least a portion of gas removed from gas conducted through the primary circuit, said secondary circuit being connected in one end to the primary circuit and in another end to said gas line upstream said first compressor. The system further includes means therein for reducing the pressure of said portion of gas conducted through the secondary circuit, and a first valve for controlling a flow of said portion of gas into the secondary circuit.

Claims23

Dependent claims

A process for the production of sponge iron from iron ore, the process comprising the steps of:

charging iron ore into a direct reduction shaft;
introducing a hydrogen-rich reduction gas from a reduction gas source into the direct reduction shaft in order to reduce the iron ore and produce sponge iron;
removing a top gas from the direct reduction shaft, said top gas comprising unreacted hydrogen gas;
conducting in a primary circuit at least a part of the removed top gas and mixing said part with reduction gas from the reduction gas source at a point downstream of a first compressor provided in a gas line leading from the reduction gas source to the direct reduction shaft, and introducing the mixture into the direct reduction shaft;
and
removing from said primary circuit a portion of the gas conducted therein, and conducting said portion of gas through a secondary circuit while reducing the pressure of said portion of gas, and mixing said portion of gas with reduction gas from the reduction gas source at a point in said gas line upstream of said first compressor.

3 more elements

A system for the production of sponge iron, the system comprising:

a direct reduction shaft comprising
a first inlet for introduction of iron ore into the shaft;
a first outlet for removing sponge iron from the shaft;
a second inlet for introduction of a reduction gas into the shaft, and
a second outlet for removal of top gas from the shaft;
a reduction gas source connected through a gas line with the reduction gas inlet;
a first compressor provided in said gas line;
a primary circuit for conducting at least a part of the top gas therethrough, said primary circuit being connected in one end with the second outlet and in another end with said gas line downstream of said first compressor,
a secondary circuit for conducting at least a portion of gas removed from gas conducted through the primary circuit, said secondary circuit being connected in one end to the primary circuit and in another end to said gas line upstream of said first compressor, and comprising means therein for reducing the pressure of said portion of gas conducted through the secondary circuit, and
a first valve for controlling a flow of said portion of gas into the secondary circuit.

7 more elements

Dependencies are inferred from the claim text.

Hydrogen gas recycling in a direct reduction process

Life of this patent

Hydrogen gas recycling in a direct reduction process

Life of this patent

Abstract

Claims23