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 invention relates to a method for producing an expanded granulate (29) made of a sand grain-shaped mineral material (1) using a propellant; wherein the material (1) is fed to a substantially upright furnace (2); wherein the material (1) is conveyed along a conveying path (4) through a plurality of vertically separated healing zones (5) in a furnace shaft (3) of the furnace (2), wherein each heating zone (5) can be heated by at least one independently controllable heating element (6); wherein the material (1) is heated to a critical temperature at which the surfaces (7) of the sand grains (1) become plastic and the sand grains (1) are expanded through the propellant. It is provided according to the invention that the material (1) is fed together with an amount of air from below, wherein the material (1) is conveyed from bottom to top along the conveying path (4) by means of the amount of air which flows from bottom to top within the furnace shaft (3) and forms an air flow (14), and wherein the expanding of the sand grains (1) occurs in the upper half, preferably in the uppermost third, of the conveying path (4).

The invention relates to a method for producing an expanded granulate (29) made of a sand grain-shaped mineral material (1) using a propellant; wherein the material (1) is fed to a substantially upright furnace (2); wherein the material (1) is conveyed along a conveying path (4) through a plurality of vertically separated healing zones (5) in a furnace shaft (3) of the furnace (2), wherein each heating zone (5) can be heated by at least one independently controllable heating element (6); wherein the material (1) is heated to a critical temperature at which the surfaces (7) of the sand grains (1) become plastic and the sand grains (1) are expanded through the propellant. It is provided according to the invention that the material (1) is fed together with an amount of air from below, wherein the material (1) is conveyed from bottom to top along the conveying path (4) by means of the amount of air which flows from bottom to top within the furnace shaft (3) and forms an air flow (14), and wherein the expanding of the sand grains (1) occurs in the upper half, preferably in the uppermost third, of the conveying path (4).

An abrasion-resistant material for the working face of a metallurgical furnace cooling element such as a stave cooler or a tuyere cooler having a body comprised of a first metal. The abrasion-resistant material comprises a macro-composite material including abrasion-resistant particles which are arranged in a substantially repeating, engineered configuration infiltrated with a matrix of a second metal, the particles having a hardness greater than that of the second metal. A cooling element for a metallurgical furnace has a body comprised of the first metal, the body having a facing layer comprising the abrasion-resistant material. A method comprises: positioning the engineered configuration of abrasion-resistant particles in a mold cavity, the engineered configuration located in an area of the mold cavity to define the facing layer; and introducing molten metal into the cavity, the molten metal comprising the first metal of the cooling element body.

An apparatus for production of burnt lime or dolomite has: a shaft furnace having a preheating zone, a reaction zone, a separation zone and a cooling zone; a first feed apparatus for CO.sub.2 at the boundary of the separation zone to the reaction zone; a first removal apparatus at the boundary of the cooling zone to the separation zone; a second removal apparatus for CO.sub.2 at the start of the preheating zone; and at least one heating apparatus, wherein the heating apparatus has a regenerator system.

The regenerator system has at least two regenerators, a preheater, a feed for fuel and a feed for fresh air; the second removal apparatus opens into the at least one heating apparatus; and the first feed apparatus is formed by the at least one heating apparatus for the shaft furnace.

An apparatus for production of burnt lime or dolomite has: a shaft furnace having a preheating zone, a reaction zone, a separation zone and a cooling zone; a first feed apparatus for CO.sub.2 at the boundary of the separation zone to the reaction zone; a first removal apparatus at the boundary of the cooling zone to the separation zone; a second removal apparatus for CO.sub.2 at the start of the preheating zone; and at least one heating apparatus, wherein the heating apparatus has a regenerator system.

The regenerator system has at least two regenerators, a preheater, a feed for fuel and a feed for fresh air; the second removal apparatus opens into the at least one heating apparatus; and the first feed apparatus is formed by the at least one heating apparatus for the shaft furnace.

A sintering furnace can have a housing, one or more heating elements, and a conveying assembly. Each heating element can be disposed within the housing and can subject a heating zone to a thermal shock temperature profile. A substrate with one or more precursors thereon can be moved by the conveying assembly through an inlet of the housing to the heating zone, where it is subjected to a first temperature of at least 500? C. for a first time period. The conveying assembly can then move the substrate with one or more sintered materials thereon from the heating zone and through an outlet of the housing.

A method for producing lime or dolime, which includes a calcination step for the calcination of calcareous or dolomitic material which is brought into contact with the first fumes which are obtained by combustion of fuel with an oxidizing gas, a cooling of calcined lime or dolime with discharge and collection thereof and a release of a gaseous effluent containing CO.sub.2. Subsequent processing steps result in the formation of a CaO-based sorbent material with separation between the CaO-based sorbent material and a CO.sub.2-concentrated gas stream which is collected. The recycling of said separated CaO-based sorbent material is recycled into a CO.sub.2 depletion step resulting in the extraction of a valorizable fraction of the CaCO.sub.3CaO based charge with a compensatory introduction of fresh CaCO.sub.3 in the calcination step.

A method for producing lime or dolime, which includes a calcination step for the calcination of calcareous or dolomitic material which is brought into contact with the first fumes which are obtained by combustion of fuel with an oxidizing gas, a cooling of calcined lime or dolime with discharge and collection thereof and a release of a gaseous effluent containing CO.sub.2. Subsequent processing steps result in the formation of a CaO-based sorbent material with separation between the CaO-based sorbent material and a CO.sub.2-concentrated gas stream which is collected. The recycling of said separated CaO-based sorbent material is recycled into a CO.sub.2 depletion step resulting in the extraction of a valorizable fraction of the CaCO.sub.3CaO based charge with a compensatory introduction of fresh CaCO.sub.3 in the calcination step.

The present disclosure relates to a decarbonation process of carbonated materials, in particular limestone and dolomitic limestone, with CO.sub.2 recovery in a multi-shaft vertical kiln (MSVK) comprising a first and a second shaft with preheating, heating and cooling zones and a cross-over channel between each shaft. The method includes alternately heating carbonated materials by a combustion of at least one fuel with at least one comburent, up to a temperature range in which carbon dioxide of the carbonated materials is released, the combustion of the fuel and the decarbonation generating an exhaust gas. Decarbonated materials are cooled in the cooling zones with one or more cooling streams. The process further includes extracting the exhaust gas from the multi-shaft vertical kiln and feeding a buffer with the extracted exhaust gas.