Energy consumption of a laboratory jaw crusher during normal and high strength concrete recycling

Abstract

This paper presents the measurement and analysis of energy consumption of a laboratory jaw crusher during concrete recycling. A method was developed to estimate the power requirements of a lab-scale jaw crusher. The impact of material properties on the crusher performance is studied. Eight concrete strength classes (C20/25–C80/95) were considered in the approach. Concrete specimens were cured for 28 days; at which time, concrete properties were obtained through tests such as bulk density, compressive strength, tensile strength, rebound number and ultrasonic pulse velocity. The impact of different aperture size (5 mm and 25 mm) on the energy consumption was also studied. From the experimental results, it is demonstrated that there is a strong dependance of energy consumption on the compressive strength of concrete. Energy of crushing for specimens with a 90 MPa compressive strength was four times higher than the energy needed to crush specimens with a 28 MPa compressive strength. Furthermore, the crushing requires three times more energy when the smaller aperture size is used to process concrete specimens. The results of this study can form a basis for a future large-scale field analysis and a detailed determination of the energy and economic efficiency of concrete recycling.