GBFS/GBS Granulated Blast Furnace Slag/Granulated Blastfurnace Slag is the result of a blast furnace combustion residues is a non-metal products which is a granular material/granular. GBFS element consists mostly of lime, silica and alumina contained with iron when feeded into the furnace.




Splitting reaction between iron/steel with other elements of this occurred after heated with 1.600C temperature inside the furnace (blast furnace) that will turn it into a liquid. When this fluid is cooled by dipping it into the water, there will be crystal called as GBFS. The crystal grains can be used as an aggregate substitute.

GBFS has a chemical composition not unlike the natural bahanmineral materials include materials such as PortlandSemen hydration. GBFS when finely ground will have a highly reactive properties that can be used as a substitute for cement. Therefore seringjuga used as a mixture of Portland cement in pembuatanbeton, mortar, grouts and others. A mixture of cement products is called sebaga isemen blended.

GBFS finely milled referred to as GGBFS / GGBS Ground granulated Blast Furnace Slag / Ground granulated Slag Blastfurnace.

Usage GBFS or GGBFS has been long known in the field of buildings along with the development of science, especially in the field of concrete. History records the development of its use as follows:


1824 John Aspdin patented the Portland Cement
1862 In Germany, Emil Langin discovered GGBFS Cement
1880 GGBFS are used together with Portland cement as activator in Germany
1996 The USA has begun produce and use GGBFS cement
1914 GGBFS plant establishment in Scotland
 1990 China has been using GGBFS in concrete admixtures
1955–1995 During this period, Germany has produced more than 1.1 billion tons of cement in which there was mixed 150 million tons of GGBFS.

During that time several countries in the world have been using GGBFS as material for cement mix / blended like China, Ireland, Australia, South Korea and others.


Total production of GGBFS in China has reached 100 million tons per year.


UK has been used for more than 2 million tons of GGBFS a year, while the total usage in Europe reached 17.7 million tons annually.


Current usage of GGBFS as Portland cement substitute material with many advantages it has been very well known in the world even GBFS or GGBFS freely traded. In Indonesia, the use of this material has not been well communicated. Especially GBFS / GBS is still categorized as hazardous and toxic wastes which the producer, container, carrier, and user / processing is limited by regulatory and permits are very strict.