Comparison of Thermochemical and Physical Properties of Some Indonesian Agricultural Wastes

Abstract

Indonesia is one of the largest agricultural countries in the world. Two main agricultural sub-sectors in Indonesia are food crops and estate crops. Agricultural waste is one of the biomass energy sources that has the potential to replace fossil energy sources. The weakness of energy sources from different types of agricultural waste is their heterogeneous thermochemical and physical properties. The objective of the experimental study is to compare the thermochemical and physical properties of fourteen selected agricultural wastes in Indonesia. The thermochemical properties that were compared are high heating value (HHV), percentage of lignocellulosic components, and ultimate analysis, while that of physical properties are the grindability, hydrophilicity, and proximate analysis. A material with high fixed carbon, low moisture, and low ash contents is preferred as a solid fuel source. Based on the experimental results of proximate analysis, coffee husk has the highest fixed carbon content (20.85%). Empty fruit bunch has the lowest moisture content (7.04%). Palm kernel shell has the lowest ash content (1.82%). Based on the results of the ultimate analysis, the palm kernel shell is the sample with the highest carbon content (49.42%), while the empty fruit bunch has the highest hydrogen content (6.69%). The coconut shell was identified as containing the lowest nitrogen (0.14%) and sulfur 0.052%). Peanut shell is the easiest to grind, while empty fruit bunch is the hardest to grind materials. The hydrophilicity of sugarcane trash is lower than other samples (9.34%). Coconut shell has the highest percentage of cellulose (47.21%). Several pairs of agricultural waste have similar properties that can be used as considerations for handling management and co-utilization.