Energy Optimisation of a Single Toggle Jaw Crusher using Discrete Element Method

Authors

  • Peter Mwangi Department of Mechanical Engineering, JKUAT P.O. Box 62000-00100 Nairobi.
  • Onesmus Muvengei Department of Mechanical Engineering, JKUAT P.O. Box 62000-00100 Nairobi.
  • Thomas Mbuya Department of Mechanical and Manufacturing Engineering, University of Nairobi.
  • Mathew Ndeto Department of Mechanical Engineering, JKUAT P.O. Box 62000-00100 Nairobi.

Keywords:

Comminution, Discrete Element Method, Energy Optimisation, Single toggle jaw crusher

Abstract

Comminution process has always been associated with very low energy efficiencies. Most of the energy during
comminution is lost through noise, heat and vibrations. Therefore, it is necessary to obtain the optimal operating parameters
of a comminution machine. In this research, the efficiency of a jaw crusher has been optimised using Genetic Algorithms
(GA) and Discrete Element Method (DEM) techniques. DEM, even though a powerful tool, demands high computational
capabilities hence a scaled down jaw crusher was used for simulation purposes. The GA codes were used in determining the
critical velocity and also in developing the equation for up-scaling the jaw crusher. Critical parameters which affect the power
consumption of a jaw crusher are toggle speed, throw and reduction ratio. These parameters were varied during the simulation
as guided by the design of experiment technique. In addition, a Bonded Particle Model (BPM), was used in modelling the
rock used in the simulation. A BPM model gives more realistic results than Particle Replacement Model (PRM) and Fast
Breakage Model (FBM). To create the BPM of an irregularly shaped rock, custom API factory was coded in C++ and loaded
to EDEM software. At the end of this research, the optimal energy efficiency was obtained as 59.7758% at a toggle speed
of 157.7965 rpm, a throw of 33.445 mm and a reduction ratio of 4. A mathematical model showing the relationship between
energy efficiency and process parameters was also developed.

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Published

2020-09-16

How to Cite

Mwangi, P., Muvengei, O., Mbuya, T., & Ndeto, M. (2020). Energy Optimisation of a Single Toggle Jaw Crusher using Discrete Element Method. JOURNAL OF SUSTAINABLE RESEARCH IN ENGINEERING, 5(4), 180-193. Retrieved from https://jsre.jkuat.ac.ke/index.php/jsre/article/view/98