Ggbs

GGBSGround granulated blast furnace slag (GGBS) is a by-product from the blast-furnaces used to make iron. Blast-furnaces are fed with controlled mixture of iron-ore, coke and limestone, and operated at a temperature of about 1,500C. When iron-ore, coke and limestone melt in the blast-furnace, two products are produced molten iron, and molten slag. The molten slag is lighter and floats on the top of the molten iron. The molten slag comprises mostly silicates and alumina from the original iron ore, combined with some oxides from the limestone. The process of granulating the slag involves cooling of molten slag through high-pressure water jets. This rapidly quenches the slag and forms granular particles generally not bigger than 5mm. The rapid cooling prevents the formation of larger crystals, and the resulting granular material comprises around 95% non-crystalline calcium-aluminosilicates aluminosilicates. The granulated slag is further processed by drying and then grinding in a rotating Ball Mill to a very fine powder, which is GGBS. GGBS can be used as a direct replacement for ordinary cement on one-to-one basis by weight. Replacement rate for GGBS vary from 30% to up to 85%. Generally 50% is used in most applications. Higher replacement rates up to 85% are used in specialist applications such as in aggressive environments and to reduce heat of hydration. GGBS can be used at replacement levels of 70% in lean mix concrete.Elements Guaranteed Specs Typical analysis CaO 34% Max 36.30% SiO2 35% Max 31.25% MgO 9% Max 7.60% Al2O3 24% Max 21.60% MnO 1% Max 0.2% FeO 1.25% Max 0.69% S 1.2% max 0.76% TiO2 1% Max 0.83% Na2O 0.3% Max 0.17% K2O 0.8% Max 0.60% Chloride 0.05% Max 0.025% Glass SiO2 89% Min 90.20% Basicity(CaO+MgO+Al2O3)/SiO2) 2% Max 1.17% Moisture 2-3% Max 10% Finesse 3700 97% (- 5 mm)