The uses of SS in various application in Europe 2016 is presented in Fig.1 [10]. As can be seen from Fig.1, about 46% of SS is used in road construction as a part of aggregate, whilst about 4.4% is used in cement production. About 8.6% is used in internal storage, whilst 11% and 6.6% is used for metallurgical and others, respectively. Finally about 14.1% is disposed in landfill.