Modelling the effect of compaction pressure on the densification of agricultural waste briquettes

Abstract

An empirical model for predicting the required compaction pressure of heterogeneous briquettes was developed in this study. The study was based on low-pressure compaction, where the used of binders is paramount. Three agricultural wastes: sawdust, rice husk, and palm kernel shell were used in the study. The material type was a key factor of influence on the briquette samples produced. The optimum compaction pressures of the homogeneous briquettes were 686.5, 981, and 981 N/cm², for sawdust, rice husk, and palm kernel shell, respectively. The predicted required compaction pressures of the heterogeneous briquettes, as predicted from the model, ranged from 715 N/cm² to 950 N/cm² for sawdust/palm kernel shell briquettes, 710 N/cm² to 906 N/cm² for sawdust/rice husk briquettes, and 936 N/cm² to 975 N/cm² for palm kernel shell/rice husk briquettes. The heterogeneous briquette samples compacted at the predicted required compaction pressures offered better quality briquettes in terms of density and calorific value than those compacted at a fixed compaction pressure of 1177 N/cm². It was established that the developed model offered ease of compaction and effective utilization of materials and will be of great use in the design of variable pressure briquetting machines.

Keywords:

• briquettes
• compaction pressure
• densification
• homogeneous
• heterogeneous

Acknowledgement

I wish to acknowledge the contribution of my supervisor, Prof. P. K. Oke, to this work and this paper, and the support of my institution during the course of this research. The bulk of the text and data presented in this paper are from my Master's Thesis, which is the report of the original research work submitted to the Department of Mechanical Engineering, School of Engineering and Engineering Technology, Federal University of Technology, Akure, Nigeria. No funding or grant or sponsorship was received for this research work.

Disclosure statement

No potential conflict of interest was reported by the authors.