Research


Goals

The Stagg-Williams’ group primary focus is on the production and characterization of alternative fuels. These fuels include bio-derived liquid hydrocarbons (gasoline, diesel, and jet fuel), biodiesel, and synthesis gas (hydrogen and carbon monoxide). In addition to studying new catalysts, reaction engineering and process intensification strategies for the production of these fuels, we are actively investigating new characterization techniques to improve the measurement and prediction of feedstock and fuel properties. We are ultimately interested in correlating feedstock composition to fuel properties in order to be able to predict thermochemical properties of biofuels as well as engine performance and emission profiles.

Projects

Wastewater Cultivated Algae

Algae is cultivated by collaborators using effluent from after the second clarifier from the Lawrence, KS Municipal Wastewater Treatment Plant (WWTP). We then determine the elemental content and energy density. Cultivating algae with wastewater serves dual benefit by polishing wasterwater to reduce nutrient concentrations that pose environmental hazards while producing biomass for fuel conversion. This wastewater algae is very different than typical controlled fertilized algae; comparatively having lower lipid and carbon content with higher inorganic and oxygen content. This combination may seem to be a counter measure to producing fuels, however after thermochemical conversion with subcritical water the high level of inorganics seem to play catalytic roles in producing a biocrude of superior quality to those produced from controlled fertilized cultivated algae.

Hydothermal Liquefaction (HTL)

We currently have the capacity to perform thermochemical conversion with variable reactor (batch) volumes from 10mL to 1.5gal and are working toward a continuous reactor design. HTL of WW-algae give three main products; biocrude oil, solid biochar, and an aqueous co-product (ACP). Our latest study calculates that the Lawrence WWTP can produce 6-9 barrells of crude oil and >1.5 metric tons of biochar perday. The biocrude has similar properties to that of petrolem crude in terms or elemental and molecular composition, H/C and O/C ratios, and energy density. The high level of biochar production is a direct result from the high level of inorganics present in the starting algae. Where the majority of the inorganic material resides in the solid biochar. The ACP contain some of the algal phosphorus and >50% of the algal nitrogen, therefore is suitable for studies for recycling to algal growth.

Biochar

Algal biochar has multiple uses. The biochar still contains >20% organic material and can be burned as a coal supplement; burning much cleaner than coal because the low levels of sulfur and soot formation. A more valuable use for biochar would be as either an absorbent material such as activated carbon or as a soil amendment/ solid fertilizer. We are currently pursuing the efficacy of biochar for such applications.

ACP

Current research is ongoing with collaborators to determine optimal recycle amounts of ACP that could be recycled for both heterotropic (bacteria) and autotrophic (algae) growth for more available biomass to be converted to crude oil.

Biodiesel is the most widely used biomass-based diesel fuel in the United States, with a current production capacity of approximately 2 billion gallons according to the Energy Information Agency. The use of biodiesel in place of or in blends with petroleum-based diesel fuel helps reduce net carbon dioxide and sulfur emissions. In small blend percentages, biodiesel can be used in most engines with no modifications.

Optimizing biodiesel’s affect on engine performance, in small and large blend percentages, will help maximize the fuel’s environmental benefit. Biodiesel’s use as a fuel can be improved with a significant increase in understanding of the physicochemical properties of the fuel prior to injection. Fuel at injection conditions is commonly one thousand times higher than at ambient.

The focus of our work, performed in collaboration with Professor Chris Depcik of Mechanical Engineering and Professor Aaron Scurto of Chemical and Petroleum Engineering, is to collect and model the important property data of biodiesel and biodiesel blends with diesel fuel. Past and current work has focused on viscosity at pressures up to 131 MPa for biodiesel feedstock (soy, canola, etc.) and blend percentage with petroleum diesel, pressure-induced freezing points, and other thermodynamic properties.

The KU Biodiesel Initiative is a grassroots, student-run operation to produce biodiesel from used cooking oil generated on campus. The Initiative focuses on research, sustainability, and outreach. It is our ultimate goal to meet the requirements of all KU's buses, landscaping and maintenance equipment, and power generators on campus with this renewable fuel.

Specific Goals of the Biodiesel Initiative

Fuel Production
  • Establish a facility to produce biodiesel from used vegetable oil at KU.
  • Create a closed-loop production process with regards to byproduct reuse, resource conservation, and energy management.
Biodiesel Quality Standards
  • Obtain the equipment and experience necessary to perform ASTM testing of biodiesel.
  • Develop a self sustaining ASTM testing facility for biodiesel to provide a testing service to the State of Kansas and broader community.
Research
  • Investigate the effect of feedstock characteristics on the biodiesel properties, engine performance, and emission quality at all stages from "Feedstock to Tailpipe".
  • Lessen the ecological footprint of the facility and focus efforts towards the benefit of economy, community, and environment.