Properties and bulk drying of biomass

Abstract

<p>A converted trailer-based peanut dryer was tested to determine its suitability and performance for drying biomass materials. These small-scale drying devices are capable of transporting, storing and dry biomass after harvest. Corn stover was dried from a range of initial moisture content of 14 to 31% down to 6%. Corn cobs were dried from 22% to 9% moisture content. Based on the test results, the energy requirement of the trailer is very high. Among the tests, test 12/2/2009 (Half load stover) was found to be the test with the highest energy requirement and Test 11/17/2009 (Full load cobs) required the least amount of energy. Air leaks and environmental conditions greatly influenced the energy requirements of the system. In the trailers present state, it was able to dry biomass adequately; however design modifications are needed to solve handling and logistical issues. Recommended modifications were listed based on the results and observations from the experiment. These modifications apply to the three main operational categories of the drying process: loading, drying and unloading. With these modifications in place, it is projected that drying efficiency and handling issues can be improved. Based on the experiment, bulk handling of biomass is a pertinent issue for its overall acceptance. Material properties of biomass such as friction coefficient are essential for designing machines and equipments that can improve processing efficiency. A method to determine the friction coefficient of corn residue was developed based on procedures used for grain. The method was capable of determining static and dynamic friction coefficient of corn harvest residues on different types of surfaces. HDPE and oak was found to be the material with the smallest and highest static friction coefficient respectively. This result was also true for the dynamic friction coefficient.</p>