Provided is a concrete composition, including: blast furnace slag; at least any one of expansive additive and cement; and water, wherein a unit water content of the water is 130 kg/m.sup.3 or less; wherein a content of the cement is 22% by mass or less relative to the blast furnace slag, and wherein a slump flow value of the concrete composition is 40 cm or greater.

Provided is a concrete composition, including: blast furnace slag; at least any one of expansive additive and cement; and water, wherein a unit water content of the water is 130 kg/m.sup.3 or less; wherein a content of the cement is 22% by mass or less relative to the blast furnace slag, and wherein a slump flow value of the concrete composition is 40 cm or greater.

Provided is a concrete composition, including: blast furnace slag; at least any one of expansive additive and cement; and water, wherein a unit water content of the water is 130 kg/m.sup.3 or less; wherein a content of the cement is 22% by mass or less relative to the blast furnace slag, and wherein a slump flow value of the concrete composition is 40 cm or greater.

A method for preparing Portland cement includes: respectively weighing iron slag, copper slag, vanadium slag, and nickel slag and grinding, to yield prefabricated iron slag, prefabricated copper slag, prefabricated vanadium slag, and prefabricated nickel slag; weighing mica and kaolinite, mixing, and grinding to obtain aluminous raw materials; evenly mixing the prefabricated iron slag and the aluminous raw materials, and calcining, to yield an iron-aluminum eutectic mineral; weighing the marble, fluorite, dolomite, and quartz, evenly mixing the marble, fluorite, dolomite, and quartz with the prefabricated copper slag, prefabricated vanadium slag, and prefabricated nickel slag to yield a first mixture; grinding the iron-aluminum eutectic mineral to yield powders, and calcining a second mixture of the first mixture and the powders, to yield the cement clinker; and cooling the cement clinker, and grinding a third mixture of the cooled cement clinker and the gypsum, to yield the Portland cement.

Provided is a blocking material and a method for manufacturing alloy steel using the same. In maintaining a molten ferro alloy, used when manufacturing a manganese-containing alloy steel, at a temperature of at least a melting point of the ferro alloy, a blocking material layer is formed on the melt surface of the molten ferro alloy by using a blocking material which includes, with respect to the total of 100 wt %, 37-66 wt % of CaO and SiO.sub.2, 8-15 wt % of Al.sub.2O.sub.3, 6-18 wt % of MgO, and 20-30 wt % of MnO, wherein the ratio of CaO to SiO.sub.2 (CaO/SiO.sub.2) is in a range of 0.95-1.2. Thus, nitrogen in the air may be prevented from being mixed into the molten ferro alloy.

A cementitious nano-engineered method and resultant composite includes a modified aggregate material configured from a plurality of fine aggregate particles (FAg) particles pretreated with a graphene oxide (GO), wherein the graphene oxide (GO) is further arranged as a plurality of crosslinked structures that arranges for a refined interfacial zone (ITZ) with a thickness of 3 ?m to 10 ?m; and a water/cement (w/c) ratio content configured with the modified aggregate material. The interface of modified aggregate and a cementitious phase largely determines the mechanical properties and durability performances of cement mortar and concrete. Moreover, the methods and composites also provide for a targeted and more efficient approach to develop smart cement composites through nanoengineering of the interfacial transition zone.

A cementitious nano-engineered method and resultant composite includes a modified aggregate material configured from a plurality of fine aggregate particles (FAg) particles pretreated with a graphene oxide (GO), wherein the graphene oxide (GO) is further arranged as a plurality of crosslinked structures that arranges for a refined interfacial zone (ITZ) with a thickness of 3 ?m to 10 ?m; and a water/cement (w/c) ratio content configured with the modified aggregate material. The interface of modified aggregate and a cementitious phase largely determines the mechanical properties and durability performances of cement mortar and concrete. Moreover, the methods and composites also provide for a targeted and more efficient approach to develop smart cement composites through nanoengineering of the interfacial transition zone.

The present invention is proposed to disclose a method for preparing an all-solid waste-based carbonated unburned lightweight aggregate. The method includes the following steps: (1) subjecting an active component type solid waste, a lightweight filling type solid waste, and an alkali activation type solid waste to grinding and mixing to obtain a mixed solid waste powder; and (2) subjecting the mixed solid waste powder and water to granulation to obtain particles, and subjecting the particles to precuring and mineralization curing with CO.sub.2 to obtain the all-solid waste-based carbonated unburned lightweight aggregate. The active component type solid waste includes blast furnace slag, steel slag, or furnace slag. The lightweight filling type solid waste includes fly ash, river silt, or red mud. The alkali activation type solid waste includes carbide slag. In the present invention, all raw materials are selected from solid wastes, the alkali activation type solid waste is used as an alkali activator to replace traditional quicklime, sodium hydroxide, and sodium silicate, and a CO.sub.2 mineralization strengthening technology is used, so that the carbon fixation potential of the solid wastes is fully exerted, natural resources are saved, and the all-solid waste-based carbonated unburned lightweight aggregate prepared has excellent compressive strength.

A method for preparing Portland cement includes: respectively weighing iron slag, copper slag, vanadium slag, and nickel slag and grinding, to yield prefabricated iron slag, prefabricated copper slag, prefabricated vanadium slag, and prefabricated nickel slag; weighing mica and kaolinite, mixing, and grinding to obtain aluminous raw materials; evenly mixing the prefabricated iron slag and the aluminous raw materials, and calcining, to yield an iron-aluminum eutectic mineral; weighing the marble, fluorite, dolomite, and quartz, evenly mixing the marble, fluorite, dolomite, and quartz with the prefabricated copper slag, prefabricated vanadium slag, and prefabricated nickel slag to yield a first mixture; grinding the iron-aluminum eutectic mineral to yield powders, and calcining a second mixture of the first mixture and the powders, to yield the cement clinker; and cooling the cement clinker, and grinding a third mixture of the cooled cement clinker and the gypsum, to yield the Portland cement.

The present invention provides an apparatus and a method for producing cement through flue gas desulfurization, and specifically provides an apparatus and a method for simultaneously producing magnesium sulfate cement during a magnesium oxide based flue gas desulfurization process. The apparatus of the present invention includes a flue gas desulfurization equipment, a concentration equipment, a crystallization equipment, a centrifugation equipment, a drying equipment, a waste ash supplying equipment, a slag material supplying equipment, a mixing equipment, etc. By adopting the apparatus and method of the present invention, the problems in the present conventional cement production such as high energy cost, severe damage to the environment and so on can be solved, and the problems like high production cost of ordinary magnesium sulfate cement and high transportation cost of supplies thereby causing incapability in a large scale market spreading and application can also be solved.