Harvesting Nitrogen, Phosphate, and Potassium from Game Day

Wastewater for Use as Fertilizer for Florida Field at Ben Hill

Griffin Stadium

Bryce Zinckgraf

(B.S., 2014)

Camille Liebnitzky

(B.S., 2012)

Dr. Treavor H. Boyer

Overview and Objectives

Every game day, approximately 90,000 Gator fans fill Ben Hill Griffin Stadium. This creates a unique

situation in which a key symbol of UF can be used to make UF a national leader in sustainability. During a Gator

football game, wastewater is expected to be almost entirely composed of diluted urine. Using source-separation

techniques, it is expected that valuable nutrients such as nitrogen, phosphate, and potassium could be harvested from

the wastewater. These nutrients are the principle components of fertilizer and could in turn be used as fertilizer for

Florida Field. This process would offer many benefits including conserving drinking water, cutting fertilizer

expenses, and offering UF the opportunity to be a leader in sustainability.

The current approach to wastewater treatment wastes valuable resources such as water, nutrients, and

energy. Clean drinking water is used to flush toilets and urinals, and all sources of wastewater are combined prior to

treatment. Although urine accounts for ~1% of wastewater by volume, it contributes > 80% nitrogen, 50%

phosphorus , and 50% potassium. Source separation of urine wastewater presents the opportunity to conserve water

and energy and recover nutrients for beneficial use. In addition, phosphate rock mining in Florida accounts for

approximately 75% of U.S. phosphate supply and 25% of the global phosphate supply. Phosphate mining accounts

for thousands of acres of strip-mining per year, damaging the environment, and nearly all the phosphate is used to

produce fertilizer.

The goal of this research project is to harvest nitrogen, phosphate, and potassium from game day

wastewater for use as fertilizer. This goal will be approached by identifying the volume and composition of

wastewater produced at Ben Hill Griffin Stadium during a Gator football game. The amount of fertilizer used on

Florida Field and its composition will also be determined. A simple mathematical model will be created to

determine the amount of fertilizer that could be produced from nutrients in urine wastewater produced during a

football game. Technologies available for harvesting nutrients from urine will also be explored at the laboratory

scale including precipitation and adsorption. Information will be acquired by talking to faculty experts on campus,

reading peer-reviewed literature, and conducting laboratory experiments.

It is expected that through source separation of urine wastewater at Ben Hill Griffin Stadium, enough

nitrogen, phosphate, and potassium could be harvested to produce fertilizer to supplement the fertilizer used on

Florida Field or other areas on campus. This would benefit the university by conserving water, reducing fertilizer

expenses, and promoting sustainability. This research project has long-term applications related to water and

wastewater sustainability, resource recovery, and reducing the environmental impact of phosphate mining in Florida.

Treavor H. Boyer, Ph.D. ~ Assistant Professor ~ Department of Environmental Engineering Sciences ~ University of Florida

thboyer@ufl.edu ~ 352.846.3351 ~ www.ees.ufl.edu/homepp/boyer ~ www.twitter.com/WaterWeUpTo