A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

A cement dispersant comprises component i) and at least one of components ii) and iii). Component i) is a naphthalenesulfonic acid polycondensate being obtainable by a condensation reaction of i-1) a naphthalenesulfonic acid, i-2) an alkoxylated hydroxyaryl compound having a polyoxyalkylene chain with 3 to 130 oxyalkylene units, and i-3) formaldehyde, in a weight ratio of i-1):i-2) of 95:5 to 60:40. Component ii) is a phosphorylated polycondensate being obtainable by a condensation reaction of ii-1) an aromatic compound having a phosphate moiety, ii-2) an alkoxylated hydroxyaryl compound having a polyoxyalkylene chain with 3 to 130 oxyalkylene units, and ii-3) formaldehyde, in a weight ratio of ii-1):ii-2) of 2:98 to 40:60. Component iii) is a polycarboxylate ether having a carbon-chain backbone with anionic and/or anionogenic groups and polyoxyalkylene side chains having an average of 3 to 130 oxyalkylene units. The cement dispersant has a good dosage efficiency and a good balance between effectiveness and cost without compromising compressive strength, while avoiding compatibility issues and viscosity increase of the dispersant.

A cement dispersant comprises component i) and at least one of components ii) and iii). Component i) is a naphthalenesulfonic acid polycondensate being obtainable by a condensation reaction of i-1) a naphthalenesulfonic acid, i-2) an alkoxylated hydroxyaryl compound having a polyoxyalkylene chain with 3 to 130 oxyalkylene units, and i-3) formaldehyde, in a weight ratio of i-1):i-2) of 95:5 to 60:40. Component ii) is a phosphorylated polycondensate being obtainable by a condensation reaction of ii-1) an aromatic compound having a phosphate moiety, ii-2) an alkoxylated hydroxyaryl compound having a polyoxyalkylene chain with 3 to 130 oxyalkylene units, and ii-3) formaldehyde, in a weight ratio of ii-1):ii-2) of 2:98 to 40:60. Component iii) is a polycarboxylate ether having a carbon-chain backbone with anionic and/or anionogenic groups and polyoxyalkylene side chains having an average of 3 to 130 oxyalkylene units. The cement dispersant has a good dosage efficiency and a good balance between effectiveness and cost without compromising compressive strength, while avoiding compatibility issues and viscosity increase of the dispersant.

A process is disclosed for the combined manufacture of steel and cement clinker. Steel scrap is loaded in an electric arc furnace for forming molten steel. Cement paste derived from construction and demolition waste is loaded in the electric arc furnace to act as a flux for the steel to assist in the removal of impurities from the molten steel and forming an electric are furnace slag. The heat of the molten steel promotes clinkering of the electric are furnace slag to form clinkered electric arc furnace slag. The clinkered electric arc furnace slag is removed from the electric arc furnace.

A process is disclosed for the combined manufacture of steel and cement clinker. Steel scrap is loaded in an electric arc furnace for forming molten steel. Cement paste derived from construction and demolition waste is loaded in the electric arc furnace to act as a flux for the steel to assist in the removal of impurities from the molten steel and forming an electric are furnace slag. The heat of the molten steel promotes clinkering of the electric are furnace slag to form clinkered electric arc furnace slag. The clinkered electric arc furnace slag is removed from the electric arc furnace.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

A dry cement mixture comprises Portland cement and an ultra-fine component consisting of at least one ultra-fine additive, said ultra-fine component being a hydraulic binder, wherein Portland cement is present in an amount of at least 70 wt % of the mixture and the ultra-fine component is present in an amount of at least 5 wt % of the mixture, wherein the ultra-fine component has a particle size distribution characterized by a particle diameter D.sub.10 of between 0.5 m and 2 m and a particle diameter D.sub.90 of between 2 m and 8 m.

A dry cement mixture comprises Portland cement and an ultra-fine component consisting of at least one ultra-fine additive, said ultra-fine component being a hydraulic binder, wherein Portland cement is present in an amount of at least 70 wt % of the mixture and the ultra-fine component is present in an amount of at least 5 wt % of the mixture, wherein the ultra-fine component has a particle size distribution characterized by a particle diameter D.sub.10 of between 0.5 m and 2 m and a particle diameter D.sub.90 of between 2 m and 8 m.