Investigation of High Speed Cone Crushing Using Laboratory Scale Experiments and DEM

Övrigt konferensbidrag, 2015

Cone crushers are commonly used in secondary and tertiary crushing stages in comminution circuits. A multitude of factors and variables influence the performance in terms of throughput capacity, size reduction, power draw and wear. Crushers are normally installed and operated at a fixed eccentric speed setting. By installing variable frequency drives and realtime optimization algorithms Hulthén and Evertsson have shown that the eccentric speed can be used as a variable to optimize the yield and improve the performance. However, the influence of eccentric speeds above the normal operational range has been scarcely reported on in the literature. This paper aims at reporting on the result from an exploratory study where experiments and simulations have been used to evaluate cone crusher operation at high eccentric speed levels ranging from 10-40 Hz. A laboratory Morgårdshammar cone crusher has been refurbished for the purpose of the study. A preliminary set of experiments have been performed where results showed that the chamber geometry has a vital importance. The same behaviour as observed in the experiments was also further understood by using DEM simulations leading to the design of a new chamber geometry. The new chamber design have been evaluated using DEM at four eccentric speeds and two different close side settings. The rock model has been calibrated by single particle breakage experiments and is based on the bonded particle model. The product particle size distribution has been estimated by image analysis of the bonded cluster discharge. The work addresses and shows results relevant to three areas in comminution and engineering research; Simulation driven design, DEM modelling, Cone crusher theory.