Ultra-rapid hardening hydraulic binder using reduced slag powder, and method of preparing the same

摘要

Provided are an ultra-rapid hardening hydraulic binder including reduced slag powder and a method of preparing the same. The reduced slag powder is prepared by rapidly cooling molten electric arc furnace reduced slag, among by-products generated during an iron refinement process in a steel mill, to room temperature not to have free-calcium oxide by scattering the molten electric arc furnace reduced slag into the air using high-pressure gas by dropping the molten electric arc furnace reduced slag through a tundish.

主权项

1. An ultra-rapid hardening hydraulic binder comprising:
reduced slag powder prepared by rapidly cooling molten electric arc furnace reduced slag, said reduced slag powder having a fineness of 3,000 to 12,000 cm2/g; wherein said reduced slag powder comprises 40 to 60% by weight of CaO, 5 to 15% by weight of SiO2, 15 to 25% by weight of Al2O3, and magnesia (MgO, Periclase) of an amount twice to three times greater than that of ordinary Portland cement or ultra-rapid hardening cement, the reduced slag powder not having free calcium oxide (free CaO) therein, wherein said reduced slag powder further comprises mayenite (C12A7, 12CaO.Al203), as a rapid hardening hydrate, and β-C2S (Belite, β-2CaO.SiO2), as a main constituent compound of cement to improve an hydraulicity; gypsum selected from the group consisting of anhydrous gypsum, natural gypsum, and hemi-hydrated gypsum to control reaction rate of rapid hardening; wherein the amount of Al2O3 in the reduced slag powder is twice to seven times greater than that of ordinary Portland cement or ultra-rapid hardening cement to substantially improve rapid hardening, early strengthening, corrosion resistance, and fire resistance properties.