Date of Graduation
12-2022
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Engineering (PhD)
Degree Level
Graduate
Department
Chemical Engineering
Advisor/Mentor
Thoma, Gregory J.
Committee Member
Greenlee, Lauren F.
Second Committee Member
Popp, Jennie S.
Third Committee Member
Matlock, Marty D.
Fourth Committee Member
Hestekin, Jamie A.
Keywords
eutrophication; life cycle assessment; nutrient recovery; struvite; wastewater treatment
Abstract
As the supply of phosphorus decreases, nutrient recovery in municipal wastewater treatment has become an important area of research. Recovery methods for phosphorus-containing fertilizers, such as struvite, and other products are currently being developed and assessed for their efficiency and economic feasibility. Potential environmental impacts from nutrient recovery are also being assessed as design for the environment is important, especially with regards to the eutrophying potential of phosphorus in phosphorus-limited freshwater aquatic systems. Life cycle assessment (LCA) is a tool that can be used to estimate potential environmental impacts of a product or service focusing on its entire life cycle. This research applies LCA to determine potential environmental benefits, as well as unforeseen burdens, that could be realized from implementation of nutrient recovery at the treatment facility scale and national scale. First, this dissertation provides an LCA of a novel electrochemical struvite precipitation method using a sacrificial Mg anode at the facility scale, the first analysis to do so (Chapter 2). Second, spatially explicit eutrophication potential from wastewater treatment discharge in the U.S. including potential changes from nutrient recovery are modeled (Chapter 3). Additionally, the work presents a new model in which eutrophication potential is disaggregated to determine whether phosphorus loading is local or resulting from upstream phosphorus emissions. In addition to expanding the body of knowledge in the realm of phosphorus recovery, these two studies also employ LCA methods that are growing areas of research: prospective and spatially explicit LCA. As emerging nutrient recovery technologies evolve, employing these developing fields of LCA can help guide decisionmakers in developing strategies to not only conserve phosphorus through nutrient recovery, but also to effectively mitigate eutrophication potential where point-sources of phosphorus are significant.
Citation
Morrissey, K. (2022). Life cycle assessment of novel electrochemical struvite recovery in municipal wastewater treatment at the plant and U.S. watershed scales. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/4710
Included in
Biochemical and Biomolecular Engineering Commons, Fresh Water Studies Commons, Water Resource Management Commons
