Blast furnace plant (1) and shutdown process for such a blast furnace plant (1). The blast furnace plant comprises a blast furnace (2) and a gas cleaning section (6) for cleaning gas from the blast furnace. Clean gas is released via a clean gas vent line (11) downstream of the gas cleaning section.

A soundproof fume discharge conduit adapted to be arranged between a ventilation system and an outlet chimney, the conduit defining a fume path therein, wherein at least one side surface of the conduit is provided with at least two protrusions, each protrusion internally defining a respective step-shaped recess, whereby the path is provided with at least two step-shaped recesses adapted to reflect sound waves propagating along the path, and wherein the step shape of each recess is defined by two first walls, which are incident at a first end thereof, and at least one wall of the two first walls is coated with a first sound absorbing material.

Recycling of low and medium radioactivity nuclear waste from VVER and RBMK reactors and other nuclear installations.

The invention uses a recycling plant consisting of a waste feed unit; a plasma shaft-type furnace with a melter in the hearth of the furnace and a slug discharge unit connected with a receiving tank for molten slug; an air supply unit delivering air to the furnace to a pyrolysis gas combustion chamber; an evaporative heat exchanger for sharp reduction of the flue gases temperature; a gas purification unit with a sock-type filter; a heat-exchanger and a scrubber; pumps and tanks for agents and recycled products; fittings; and at least, one control module which is electrically connected to the slug discharge control module, an interior environment control module, an equipment status control module and, at least, one gas analytical module.

Recycling of low and medium radioactivity nuclear waste from VVER and RBMK reactors and other nuclear installations.

The invention uses a recycling plant consisting of a waste feed unit; a plasma shaft-type furnace with a melter in the hearth of the furnace and a slug discharge unit connected with a receiving tank for molten slug; an air supply unit delivering air to the furnace to a pyrolysis gas combustion chamber; an evaporative heat exchanger for sharp reduction of the flue gases temperature; a gas purification unit with a sock-type filter; a heat-exchanger and a scrubber; pumps and tanks for agents and recycled products; fittings; and at least, one control module which is electrically connected to the slug discharge control module, an interior environment control module, an equipment status control module and, at least, one gas analytical module.

A soundproof fume discharge conduit adapted to be arranged between a ventilation system and an outlet chimney, the conduit defining a fume path therein, wherein at least one side surface of the conduit is provided with at least two protrusions, each protrusion internally defining a respective step-shaped recess, whereby the path is provided with at least two step-shaped recesses adapted to reflect sound waves propagating along the path, and wherein the step shape of each recess is defined by two first walls, which are incident at a first end thereof, and at least one wall of the two first walls is coated with a first sound absorbing material.

The present disclosure relates to a process for the decarbonation of limestone, dolomite or other carbonated materials. The process may include heating particles of carbonated materials in a reactor of a first circuit to obtain decarbonated particles. Particles of carbonated materials are conveyed by a first entraining gas in the first circuit for preheating. The gas includes the carbon dioxide, the gas composition being substantially free of nitrogen. The carbonated particles are separated from a first entraining gas flow. The decarbonated particles are transferred to a cooling section of a second circuit having a second entraining gas in which the conveyed decarbonated particles release a portion of their thermal energy. The decarbonated particles are separated from a second entraining gas flow. The second entraining gas is substantially free of carbon dioxide.

The present disclosure relates to a process for the decarbonation of limestone, dolomite or other carbonated materials. The process may include heating particles of carbonated materials in a reactor of a first circuit to obtain decarbonated particles. Particles of carbonated materials are conveyed by a first entraining gas in the first circuit for preheating. The gas includes the carbon dioxide, the gas composition being substantially free of nitrogen. The carbonated particles are separated from a first entraining gas flow. The decarbonated particles are transferred to a cooling section of a second circuit having a second entraining gas in which the conveyed decarbonated particles release a portion of their thermal energy. The decarbonated particles are separated from a second entraining gas flow. The second entraining gas is substantially free of carbon dioxide.

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).

An improved direct smelting system and process using a smelt reduction vessel (SRV), and optionally, a cyclone converter furnace (CCF). The improved system and process utilizes a fast quench system in which hot process offgas containing molten material is quench-cooled from greater than 1400? C. (2552? F.) to no more than 600? C. (1112? F.) in a time-of-flight of no greater than 1 second. The quenching occurs using water spray injection and vaporization to cool, stress and break solid slag into slag pieces small enough to remove from the quenching system. The improved system eliminates plant availability problems associated with (i) accretion formation in the offgas train as hot process offgas cools down in a conventional (slow) manner to allow for steam-raising for power generation or other heat recovery purposes, and (ii) trigger mechanisms causing slag foaming events in the SRV that propagate up the offgas train.