Development of thermo-mechanical treatment for recycling of used concrete

Compared to virgin aggregates concrete recyclates have some specific properties because of the attached hardened cement paste. By the method of thermo-mechanical treatment, the hardened cement paste can be removed. In this paper systematic experiments are described. The aim was to understand the liberation process better. The product quality, the parameters of the process and the interaction were experimentally investigated. The results of the study show that with a low treatment temperature of 250-300 A degrees C and a sufficient high duration of mechanical treatment recycled aggregates with properties similar to natural aggregates can be generated.