Experimental study of energy and exergy analysis of the effect of dryer temperature and particle size on biomass drying process

In this research the exergy analysis of a biomass drying system were investigated experimentally by varying some drying parameters and exergy loss, exergy efficiency as the two principal factors in analyzing systems were calculated for this dryer. Exergy is defined as useful work potential of a system in a specified state. Exergy analysis is a powerful tool in design and optimization of energy systems. Biomass, one of the most available renewable energies is defined as organic materials, such as wood, agricultural wastes, and municipal biowastes, especially when used as a source of fuel or energy. The moisture content of fresh woody biomass is typically high and it is beneficial to dry woody biomass before the process of energy yield for better performance and efficiency. In this research Drying experiments were performed in a domestic dryer. In these experiments three different inlet air temperatures, 60, 80 and 100oC and two different particle sizes of fine and coarse were considered. The results showed that the higher inlet air temperatures caused higher values of exergy loss and lower values of exergy efficiency. Also the fine particle size decreased the exergy loss and increased the exergy efficiency. Variation of parameters has changed exergy efficiency from 22 to 47 percent.