Date of Graduation


Document Type


Degree Name

Bachelor of Science in Biological Engineering

Degree Level



Biological and Agricultural Engineering


Zhang, Wen

Committee Member/Reader

Osborn, Scott

Committee Member/Second Reader

Costello, Thomas


Algae are increasingly being recognized as useful organisms for many applications in today’s world. Their ability to remove nitrogen, phosphorus, and trace metals from water while adding oxygen to water makes them an attractive tertiary treatment technology in municipal wastewater treatment facilities. At the same time, algae produce lipids and carbohydrates that are useful for biofuel production, and they are not a human food crop unlike many biofuel feedstocks. In this study the effect of increased chloride concentrations in wastewater was assessed on the ability of two species of algae, Chlorella vulgaris and Scenedesmus dimorphus, to function as a biofuel feedstock. In the first phase of the experiment, algae was cultivated in synthetic wastewater with varying chloride concentration; in the second phase secondary effluent samples from the Westside Wastewater Treatment Plant in Fayetteville, AR, were used to cultivate algae, and the chloride concentration was measured. The capacity of C. vulgaris to produce biomass and lipids was not heavily affected by increased chloride concentrations in the synthetic wastewater, but that of S. dimorphus was diminished at increased chloride concentrations. The secondary effluent had a chloride concentration ranging from six to nine times that of the synthetic wastewater recipe. S. dimorphus produced more biomass and chlorophyll than C. vulgaris in these trials, but neither species was effective in in producing lipids. Overall, the results from both phases of the experiment require replication for validation, and there are many opportunities to further this work.


biofuel feedstock, algae, chloride salt, wastewater treatment