Graduate Program

Biological Sciences and Sustainable Energy (dual degree)

Degree Name

Master of Science (MS)

Semester of Degree Completion

Spring 2018

Thesis Director

Thomas Canam

Thesis Committee Member

Barbara S. Carlsward

Thesis Committee Member

Peter Ping Liu


Society needs to find replacements for fossil fuels, which are finite resources that may be fully depleted within a few generations. While solar and wind have great potential as alternative energy sources, they are unlikely to completely replace all of the current fuel sources, particularly liquid fuels. Plant biomass has great potential for this market, and is already used in many forms for heat energy (e.g. direct combustion). However, the bulk density of important bioenergy crops, particularly grasses, is often low, which necessitates the use of binders in densification strategies. In the present study, waste algae biocake from a proprietary food-oil process was examined as a potential binding agent for the woody grass Miscanthus. Acid hydrolysis was used to determine the non-soluble material and the carbohydrate content of pure algae, Miscanthus, and blended pellets. The algae biomass had lower insoluble material (P<0.0001) and glucose content (P<0.0001) than Miscanthus, and all blends with 30% or greater algae had significantly less of both parameters. The energy content was not significantly different between algae and Miscanthus with or without blending, while algae had significantly higher ash content compared to Miscanthus. The compressive strength of the pure algae and pure Miscanthus was not significantly different; however, all algae blends of 30% or more showed significantly greater pellet strength compared to either biomass alone. Overall, the results of this study indicate that pressed algae biocake has the potential to act as a binding agent to improve pellet strength of Miscanthus in blends at 30% or higher, without sacrificing overall energy density, which suggests that the algae biocake could be a valuable co-product for biofuel industries.