Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Biological Engineering

Committee Chair(s)

Charles D. Miller


Charles D. Miller


Judith L. Sims


Ronald C. Sims


Roughly the same volume of water that rushes over the Niagara Falls is produced as wastewater in North America. This wastewater is treated through a variety of means to ensure that it can be safely returned to the natural ecosystem. This thesis examines two novel means for this treatment, one biological and one physical-chemical in nature, namely, Rotating Algae Biofilm Reactor treatment and expanded shale augmented coagulation-flocculation.

Rotating algae biofilm reactors (RABRs) support biofilm algae growth, and in turn, the algae take up harmful contaminants from the wastewater. This system was tested in wastewater from petroleum refining operations. The efficacy of the RABR system was compared with a traditional method of wastewater treatment, open pond lagoons, where wastewater is open to sunlight and algae growth occurs in suspension as compared to the biofilm formed by the RABR system. The RABR treatment demonstrated a statistically significant increase in removal of three constituents in wastewater that are harmful to the environment: nitrogen, phosphorus, and suspended solids. Additionally, the RABR treatment demonstrated increased biomass production. This biomass can be converted into a variety of bioproducts including biofuels, agricultural feed, and nutraceuticals. This study is the first demonstration of this system in petroleum refining wastewater.

Currently, many wastewater treatment facilities use coagulation-flocculation to remove suspended solids from the wastewater. To achieve this removal, coagulants are added to the wastewater, which removes surface charges of the suspended particles, allowing particles in solution to coalesce and settle by gravity out of solution. One common coagulant added to wastewater is ferric sulfate. This study demonstrated that the addition of a new compound, expanded shale, to ferric sulfate could greatly improve the efficacy of the existing ferric sulfate coagulation system.