Master of Science in Engineering, University of Akron, 2020, Civil Engineering

Excess phosphorous in water ways is known to be a cause of harmful algal blooms. These blooms have caused problems with water aesthetics and recreational use. Water Treatment Residual (WTR) has been shown to have an affinity for phosphorous. Since WTR is a bi-product of the drinking water treatment process it has the potential of being a low-cost alternative to remove excess phosphorous from water ways, potentially preventing harmful algal blooms. A previous study proved there was a beneficial reuse for WTR produced at the Akron Water Treatment plant for binding excess phosphorous. This research thesis looked further into Akron Water Treatment Plants WTR, to see if baking could increase its phosphorous adsorption capacity. Initial 24-hour sorption studies determined optimal baking temperatures of 175°C for Al-WTR (ce = 0.31 mg/L, qe = 117.21) and 150°C for PAC-WTR (ce = 0.20 mg/L, qe = 120.00). Isotherm studies for baked Al-WTR (175°C) and PAC-WTR (150°C) found that there was a net desorption of phosphorous when in distilled background solution. A statistical analysis across all experimental conditions determined that baked PAC-WTR (mean qe 11.00 mg/kg) performed significantly (ρ < 0.05) better than baked Al-WTR (mean qe 8.18 mg/kg). When the specific condition of the isotherm experiments were considered, baked PAC-WTR sorbed more PO4 (mean qe 36.64 mg/kg) (ρ < 0.05) when subjected to raw water at 20°C and static in conditions. Baked Al-WTR was the next best (mean qe 21.42 mg/kg) significantly (ρ < 0.05) in 5°C Static in raw water. Continuous flow column tests were also conducted to find the sorption maximum of the baked WTR, and to compare the adsorption capacity of As-Is WTR versus baked WTR conducted. Baked WTR was found to have an affinity for phosphorous with a sorption capacity of 7.91 mg-P/g-WTR for baked Al-WTR and 16.21 mg-P/kg-WTR. When compared to As-Is WTR, baked PAC WTR was the only material found to have a higher adsorption capacity by (open full item for complete abstract)

Committee: Teresa Cutright PhD (Advisor); Donald Ott PhD (Committee Member); Stephen Duirk PhD (Committee Member) Subjects: Civil Engineering; Engineering; Environmental Engineering; Environmental Science

Master of Science, The Ohio State University, 2012, Environment and Natural Resources

The reduction in the quality of soils is a major issue worldwide. The remediation of these lands is needed to restore ecosystem services as well to protect human health. Urban areas, already devoid of excess land, can especially benefit from soil remediation. Additions of organic amendments are an approach to remediate soil naturally. Urban by-products such a composted sewage sludge (biosolids), composted vegetative waste, water treatment residues (inorganic iron oxides removed from drinking water) (WTR), and biofuel combustion residuals (biochar) could be recycled and potentially be useful for bioremediation of degraded soils. Since there is very little information on comparing the microbial response to these amendments when added to soils, the objective of the research was to monitor enzyme activities and microbial community structure (phospholipid profiling) in soils amended with biosolids, vegetative compost, and designer amendment mix ( biosolids, biochar and WTRs) over a three year period in the field. Chapter 1 reviews common remediation methods and measurements to determine soil quality. Industrial by-products, are attractive for soil remediation because they are generally abundant, inexpensive, and promote recycling. Other materials, such as biochar and wastewater treatment residual (WTR), may enhance the effects of biosolid on the microbial biomass within soil. Therefore, an objective of Chapter 2 was to compare the effects of biosolids and vegetative composts on soil enzyme activities. Another objective was to analyze the effects of adding residual material, such as biochar and WTR, to biosolids. The objectives of Chapter 3 were to determine the effects of these amendments on the microbial community composition three years after initial application. A field study began in August 2009, with a randomized design of control soil, vegetative yard waste compost, biosolids (at 202 or 403 Mg ha-1), and a designer mix (biosolids at 202 Mg ha-1, biochar, and WTR). (open full item for complete abstract)

Committee: Richard Dick PhD (Advisor); Nicholas Basta PhD (Committee Member); Warren Dick PhD (Committee Member) Subjects: Soil Sciences