Abstract

Finding solutions to treat water that contains phosphorus is an important effort due to the harmful impacts it presents to both human health and the environment. Phosphorus is considered a limiting factor in water oftentimes and therefore controls the growth of algal bloom in a water body. The increase of algal populations due to wastewater effluent, stormwater runoff, and agricultural discharge in Florida waters has a direct link to the event of harmful algal blooms such as red tide in coastal regions, eutrophication of waterbodies, and fish kills. Finding low cost, energy efficient, and low maintenance green sorption media (GSM) solutions to treat this nutrient laden water is the main focus of this study. Phosphorus removal efficiencies were studied in the lab using two new recipes of GSM with a unique passive energy cascade upflow hydraulic pattern. The study goal involves comparing the two new GSM in terms of their removal rates of phosphate, removal mechanisms, and their differential effects via a lab-scale cascade upflow filtration system. The two new GSM include Zero-valent Iron and Perlite Green Environmental Media (ZIPGEM) composed of 85% sand, 5% clay, 5% zero valent iron, 5% perlite by volume, and Biochar zero-valent Iron and Perlite Green Environmental Media (BIPGEM) containing 80% sand, 5% biochar, 5% clay, 5% perlite, 5% zero valent iron by volume. To explore the differential effects, the addition of biochar in BIPGEM is of special interest in this study and expected to perform better than its counterpart ZIPGEM. However, results indicated that ZIPGEM, when treated as a system, experienced an average percent removal of 97.9% to 78.9% from the initial 60 minute to 300 minute range, whereas BIPGEM experienced an average 86.9% to 67.1% removal during this same time interval. At the time of shutdown for the BIPGEM runs (5,480 minutes), BIPGEM as a system possessed an average 52.8%, and ZIPGEM a 69.1% removal. Upon shutdown for ZIPGEM at the 11,180 minutes mark, ZIPGEM was still at an average 69.1% removal. Further comparison of the material structures and compositions of two GSM involve chemical composition analysis of both raw and spent media samples using X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), and scanning electron microscope (SEM) in the Advanced Materials Processing and Analysis Center (AMPAC) at the University of Central Florida (UCF). Two experimental runs with slightly different flow rates were conducted for each type of sorption medium to explore the process reliability of such a cascade upflow filtration system. Statistical analysis via the Kolmogorov-Smirnov Test was calculated to compare goodness of fit between the two sets of performance curves associated with each sorption media and experimental run in the lab. The results of this study show that the inclusion of biochar did not support the hypothesis that BIPGEM would perform better than ZIPGEM in phosphorus removal and the two experimental runs are statistically similar. This may be due to the quantity of biochar not being enough to provide significant adsorption of phosphorus or the possibility of synergistic effects between the other ingredients within the recipe altering the physical or chemical adsorption properties expected from the medium. It is recommended that further studies in a downflow filtration system (i.e., a column study) take place to continue the understanding of the impact associated with changing hydraulic pattern and higher content of biochar in the recipe based on this study.

Thesis Completion

2023

Semester

Spring

Thesis Chair/Advisor

Chang, Ni-Bin

Degree

Bachelor of Science in Environmental Engineering (B.S.Env.E.)

College

College of Engineering and Computer Science

Department

Civil, Environmental, and Construction Engineering

Degree Program

Environmental Engineering

Language

English

Access Status

Open Access

Release Date

5-15-2023

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