Tuesday, May 1, 2012
Napoleon Ballroom C-D, 3rd fl (Sheraton New Orleans)
Elisabeth Joelsson, Ola Wallberg, Mats Galbe and Guido Zacchi, Department of Chemical Engineering, Lund University, Lund, Sweden
To meet the increasing demand for renewable and sustainable energy sources, more efficient ways to utilize agricultural sources has to be investigated. Wheat is one of the most abundant crops in Europe and yields an abundance of residual straw material. The combination of wheat kernels and straw could be used to produce ethanol in a more energy-efficient way, by utilizing the energy surplus from a second-generation production plant, based on straw, to supply the first-generation plant with energy. Straw is a lignocellulosic material where the cellulose and hemicellulose can be utilized to produce ethanol and biogas, while the lignin residue can be burnt to supply energy to the processes.
Integration of 1st and 2nd generation plants will lead to higher crop utilization and could be beneficial from an energy point of view. Integration can be done in a variety of different process configurations, depending on the ingoing material and desired co-products. The process can be modeled as two stand-alone plants supplied with energy from the 2nd generation process, or by full integration of the two processes. Depending on configuration, different energy-demanding steps will occur and thus possibilities to integrate different heat sources or sinks in the processes.
These factors are considered in this study, based on laboratory trials, to identify and improve the energy utilization in combined 1st and 2nd generation processes by flowsheet simulations in Aspen Plus.