Quality of Agricultural Residues as Solid Fuel for Energy Resources

Finitude of fossil fuels and its environmental damage is a major challenge to the use of renewable energy sources such as biomass. The world's largest source of biomass is agricultural residues in this study, the possibility of using agricultural waste as fuel in the combustion chambers in the Ardabil province has been investigated. The agricultural residues of Ardabil province are studied and finally the wheat and barley straws are selected due to extra production, low nutritious for animals and excess wastes. The samples are used for elemental and ash analysis then compared with allowed limits of the technical and environmental problems. Also the TGA and combustion behavior of sample are analyzed then combustion and kinetics characteristics are calculated. Chlorine and sulfur in both samples are above the allowable level (0.1 %) leading to corrosion and pollutant emissions, nitrogen content is above the allowable level (0.7%) and this leads to the nitrogen oxides emission. So it is predicted that both the straws are not acceptable for direct usage as fuel and they need to do some complement processes. Samples of wheat straw in comparison with barley straw has higher comprehensive index of combustion and flammability index and as a result, the peak temperature and the time of maximum combustion rate and the final temperature of combustion is lower but the maximum rate of combustion is more. The activation energy and frequency factor of barley straw has higher than the wheat straw samples at the second combustion stage. Two samples are unsuitable for direct use at combustion process and the preparation procedure is required.