Analysing material flows and final fate distribution of spent refractories from steel casting ladles and cement rotary kilns in Europe

Refractories are used in high-temperature applications, consuming 35 to 40 Mt globally each year and generating 28 Mt of spent refractories (SR), primarily from steel and cement production. This paper addresses knowledge gaps in SR material flows from steel casting ladles (SCL) and cement rotary kilns (CRK) by collecting data from respective industry interviews, reports and trade balance sheets, to estimate Europe's annual refractory demand. Additionally, an approach is presented to easily estimate the amount of SR generated. In 2022, Europe consumed 2.7 Mt of refractories, with 1.36 Mt for steel and 0.14 Mt for cement production, resulting in 326 kt of SR from SCL and 74 kt from CRK. Compared to dated literature, recycling of CRK breakout material increased to 42 %, whereas no data was provided in 2003. Contrary, 52 % of SCL material is being landfilled nowadays compared to no landfilling reported in 2003. Spent refractories recovered by recyclers is utilised in novel refractory production at rates of 64 % for SCL and 81 % for CRK. This study provides the first in-depth analysis of SR handling from cement production, including an average process loss of 45 %. The findings improve the overall knowledge about the final fate of SR.