Abstract

• This research is aimed to convert the vegetable waste into valuable products as an alternative and sustainable fuel source. This study investigated the potential use of fuel pellets that are produced from the wastes such as radish leaf, rice husk and rice husk char. Some physicochemical properties such as moisture content, ash content, bulk density, and chemical composition (N and S %) of different solid waste samples were carried out using appropriate analytical methods. Furthermore, pellets were produced from radish leaf, rice husk and rice husk char using cassava stem and local algae (Spirogyra sp.) as a binder. The properties of fuel pellets (compact and relax densities, heating value, energy densities, pellet moisture content) were determined as a function of types and sample composition (60 to 80 % w/w) by applied pressure (1.7 MPa). Also comparative studies of the different samples such as radish leaf (R) with rice husk (H) and rice husk char (C) and their toasted samples (TR, TH and TC) were conducted. The results showed that energy densities ranged from 6.183 to 7.613 kJcm-3 , 0.366 to 4.387 kJcm-3 and 0.909 to 1.648 kJcm-3 for the samples R, H and C whereas energy densities ranged from 9.003 to 11.072 kJcm-3 , 0.369 to 4.760 kJcm-3 and 1.116 to 1.876 kJcm-3 for the samples TR, TH and TC, respectively. The heating value was also found in the range of 13.188 - 14.336 kJg-1 , 13.375 kJg-1 and 2.425 - 5.214 kJg-1 for samples R, H and C, and 13.737 - 14.010 kJg-1 , 12.656 - 13.333 kJg-1 and 2.891 - 5.567 kJg-1 for samples TR, TH and TC, respectively. From the findings, the radish leaf waste was found to have good pelletizing and combustion characteristics under the conditions considered because of their high density, high heating value and low pellet moisture content. Properties of the densified products (pellets) appeared to be comparable to US PFI requirements.