Table of Contents
ISRN Chemical Engineering
Volume 2014, Article ID 196103, 6 pages
Research Article

Analysis of Energy Characteristics of Rice and Coffee Husks Blends

College of Engineering and Technology (CoET), University of Dar es Salaam, P.O. Box 35131, Dar es Salaam, Tanzania

Received 6 December 2013; Accepted 3 February 2014; Published 13 March 2014

Academic Editors: J. A. González and A. Ragauskas

Copyright © 2014 Cuthbert F. Mhilu. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Production of first generation biofuels using food crops is under criticism over sustainability issues on food security. Tanzania is showing active interest in developing second generation biofuels to deal with some of such issues, especially from the feedstock point of view. This paper reports work done to determine energy characteristics of rice and coffee husks. The results show that coffee husks have better energy quality than rice husks, while heating values of coffee are 18.34 MJ/kg and 13.24 MJ/kg for rice husk. Thermogravimetric analysis made for coffee husks blended rice husks at a ratio of 75 : 25% vol. show better material degradation characteristics yielding low residual mass of 23.65%, compared to 26.50% of char and ash remaining in pure rice husks. Derivative thermogravimetric analysis shows comparable hemicellulose degradation peak values of −11.5 and −11.2 and cellulose −3.20 and −2.90 in pure coffee and rice husks, respectively. In coffee and rice husks blends, substantial reductions of hemicellulose and cellulose peaks were observed. Use of coffee and rice husks blends applying high temperature gasification would reduce the latter’s flammability, while increasing its flame retention characteristics, hence offering opportunities for production of clean syngas in a sustainable manner.