The iron and steel industry and the building materials industry are among the most energy-intensive industries in the world. By linking industries, closing material cycles and recycling, energy and resource efficiency can be increased. An established example is the granulation of blast furnace slag for use as an additive in the cement industry. This route is simulated in form of a pilot plant. The aim is on the one hand to gain insight into the optimization of blast furnace slag and on the other hand to investigate the suitability of alternative residual materials as hydraulically effective additives. In the course of the work, the basics of granulated blast furnace slag in the cement industry will be summarized. They form the basis for the design, planning and construction of the wet granulation plant. Wet granulate under varying test conditions and input materials will be produced. It is then tested for specific quality characteristics for use in the cement industry. From this, the relevant influencing variables on the slag sand quality are to be characterized and the suitability of alternative residual materials is to be proven. In addition, the pilot plant will be used to provide reference material for alternative treatment processes and to enable slag modification by the addition of aggregate.