One of the major issues regarding the commercialization of biomass feedstocks as a bioenergy source is the fact that there is only limited information available regarding their storability. One of the ways to determine if a biomass feedstock will maintain its quality under different storage conditions is to develop its moisture sorption isotherms. There are three major issues associated with the traditional method of using saturated salt solutions in desiccators to conduct moisture sorption studies: 1) lengthy period of time required to achieve equilibrium (four weeks for a single temperature), 2) difficulty of obtaining accurate measurements due to the protocol of continuously removing the biomass sample and exposing it to lab environment which often has a different relative humidity and temperature, and 3) the time-consuming, cumbersome steps required of the researcher to obtain weight measurements for the duration of the equilibration period. By acquiring an AquaLab Vapor Sorption Analyzer (Model No. 40430, Decagon Devices, Inc., Pullman, WA), both static and dynamic vapor sorption analysis can be performed with ease.
Development of biomass feedstock moisture sorption isotherms at different temperatures and relative humidities will provide critical information in determining how a biomass feedstock will react in different climates, and thus aid in establishing the optimal storage, transportation, and drying conditions. The proposed instrument will be used to study the equilibrium moisture characteristics of several biomass feedstocks. More specifically, the AquaLab Vapor Sorption Analyzer (VSA) would provide the PI the opportunity for conducting the following research activities: (1) determination of moisture sorption characteristics of sweet sorghum, energycane, napiergrass, and Paulownia; and (2) evaluation of isotherm models for describing isotherm sorption data for sweet sorghum, energycane, napiergrass, and Paulownia.
