During the last decades, biomass-based materials derived from different types of natural resources have attracted great attention because of their availability and renewable nature. Biomass wastes from agricultural and forestry activities are renewable, sustainable and available in abundance at low cost but are still underutilized. The use of fibers, obtained from residues of lignocellulosic plants and organic biomass, respectively as reinforcement and matrix, in combustible composite materials, is a very interesting alternative to manufacture briquettes for use in heating boilers instead of conventional fuels. In this context, this work proposes a sustainable strategy that transforms waste into energy by developing composite materials (briquettes), fully biodegradable and compatible with environmental policies. Its composition is based on lignocellulosic fibers of leaves, stems and branches of Hedychium gardnerianum (Kahili ginger), an invasive plant in the archipelago of the Azores that causes serious environmental problems; and animal manure, easily available on farms and agricultural land. The results showed that the obtained briquettes have a heating value (HHV) of 18.79 MJ/kg, higher than that of wood (~ 15 MJ/kg) and other solid fuels such as herbaceous biomass (17,209 MJ/kg), corn stover (16,370 MJ/kg) and forest residue (15,402 MJ/kg). On the other hand, preliminary tests were performed in the laboratory to monitor the combustion of 100 g of briquettes in terms of CO released into the environment. A portable CO sensor, detecting CO concentrations up to 350 ppm was used and the results have shown a CO concentration in air of 52 ppm. The briquettes physical and morphological characterization was performed by Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TG/DTG, mass change versus temperature), Differential Thermal Analysis (DTA, heat flow versus temperature) and Nitrogen Adsorption (BET) at 77 K. The development of composite materials (briquettes) obtained from Kahili ginger fragments (dispersed and reinforced phase) in animal waste (matrix-binder phase) is presently a very promising alternative to firewood, wood pellets and charcoal since they prevent deforestation as well. Besides, the proposed briquettes are light weight, low cost and renewable in nature. They can be made in shape of uniform size, making it easy for the transport and store.
Keywords:
Composites, Briquettes, Kahili ginger, Lignocellulosic Fiber, Organic Biomass.
Acknowledgments
The authors gratefully acknowledge the financial support from: (1) FEDER, through Programa Operacional Factores de Competitividade − COMPETE and Fundação para a Ciência e a Tecnologia − FCT, by the project UID/FIS/00068/2013; (2) Regional Government of the Azores-Fundo Regional da Ciência e Tecnologia (Fellowship M3.1.a/F/040/2015).
4b. Affordable and clean energy
