Physical and Chemical Properties of Thai Biomass Fuels from Agricultural Residues

Abstract

In Thailand, well-recognized as one of the first rank exporters of agricultural and food products, biomass has been the traditional energy source, especially in rural areas for decades. Various types of biomass are available in mostly in the form of non- plantation resources. A recent study showed that agricultural residues are the most potential considering their quantitative availability. In order to characterize the physical and chemical properties of Thai agricultural residues to be used as feedstock for energy conversion process, we developed an analytical protocole. Agricultural residues from major Thai economic crops, including paddy, maize, sugarcane and oil palm, were analyzed. In this paper, details of the analytical protocol are first described, then preliminary results are presented and discussed in comparison with data referenced in the literature. Proximate, ultimate and elemental analyses showed that Thai biomass of interest possess similar physical and chemical properties as agricultural residues biomass documented in China. Rice husk, rice straw, maize stalk and sugarcane are of moisture content, and so they are appropriate to meet requirements of thermochemical process, while residues from oil palm would be more suited for biological process. Comparatively to coal, agricultural residues biomass has a lower energy density and lower ash content. Contents in nirogen and sulfur are very low underlying potential environmental benefits of using agricultural residues as fuel for thermal power generation units. On the other hand, the content in ash-forming elements, especially in potassium is quite high, and hence it is necessary to well-quantify their concentration to prevent technical problems in operating thermochemical power plant using this type of biomass as feedstock. Preliminary results of this study could serve to establish a database of Thai biomass fuels or feedstock that would support decision making in terms of energy conversion technology selection and operating conditions setting.