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Item Selecting filter media for phosphorus removal at the Ennis National Fish Hatchery three-stage subsurface flow treatment wetland(Montana State University - Bozeman, College of Engineering, 2017) Wallis, Jack Enoch; Chairperson, Graduate Committee: Otto Stein; Otto R. Stein, Christopher R. Allen and Ellen G. Lauchnor were co-authors of the article, 'Selecting wetland media for phosphorus removal' submitted to the journal 'Water science and technology' which is contained within this thesis.In western Montana, phosphorus is one of the most common contaminants found in rivers and streams, threatening the health of aquatic ecosystems. In response to growing water quality concerns and new regulatory requirements, a three-stage treatment wetland was recently constructed at the Ennis National Fish Hatchery to treat wastewater generated by raceway cleaning operations. Currently only the first two stages of this system are complete and over the first two months of operation have removed over 98% of influent chemical oxygen demand, 99% of total suspended solids, 59% of total nitrogen, and 95% of total phosphorus. However, the effluent phosphorus concentration is expected to increase as organic matter accumulating in the wetland mineralizes and the phosphorus adsorption capacity of the wetland media is saturated. To maintain long-term phosphorus removal, the treatment wetland was designed with a filter unit to be filled with media capable of adsorbing large quantities of phosphorus. The purpose of this research is to choose the optimal media for this filter unit, comparing three manufactured materials (lightweight aggregate, juniper biochar, and lodgepole biochar) and four natural materials (limestone, dolomite, shale, and gravel). Batch adsorption experiments were conducted with coarse media in deionized water, coarse media in Blaine Spring Creek water, and fine media in deionized water. The difference between these batch experiments showed that water chemistry and particle size significantly affect phosphorus adsorption for a given material. Based on their high performance in batch experiments, lightweight aggregate and lodgepole biochar were tested in continuous flow columns, along with gravel to provide a baseline performance comparison. Gravel and lightweight aggregate removed more phosphorus in continuous flow columns than in batch experiments, likely due to ongoing precipitation with calcium ions in the influent. Lightweight aggregate was the top performing media in all experiments, and is recommended for use in the filter units at the Ennis National Fish Hatchery treatment wetland. Based on its phosphorus removal capacity in column experiments (1200 mg P kg -1 lightweight aggregate), the filter beds will be saturated in 14 months if the current effluent phosphorus concentration of 2.3 mg L -1 is maintained.Item Phosphorus uptake in an activated sludge pilot plant as a function of cell residence time(Montana State University - Bozeman, College of Engineering, 1972) Boe, Owen KennethItem Review and synthesis of engineered wetland treatment systems with application to phosphorus removal(Montana State University - Bozeman, College of Engineering, 2011) Ibarra, Diana Lynne; Chairperson, Graduate Committee: Alfred B. CunninghamNutrient contamination in point and non-point wastewater sources has led to an increased focus on the removal of phosphorus before reaching receiving waters. Phosphorus, typically a nutrient limiting contaminant is responsible for eutrophication and algae blooms in lakes and streams and the wastewater from agricultural, industrial and domestic sources is under continued scrutiny from the regulatory environment. Constructed wetlands mimic natural wetlands and are used worldwide for the removal of nutrients in wastewater streams but the research and applications for removal of phosphorus has lagged behind other nutrients and contaminants. This paper is an extensive literature review of construct wetlands and the ongoing applications for phosphorus removal. This review includes recent research on the mechanisms of removal, an evaluation of different plant species, a discussion of phosphorus partitioning in the wetland environment and a look at the use of chemical additives to improve the removal efficiency. Hybrid constructed wetland systems that closely mimic the biological nutrient removal systems for large scale WWTP facilities are being built around the world to improve effluent water quality and take advantage of the benefits of each type of constructed wetland. Maximizing the removal of phosphorus in wastewater will require a multi-pronged approach that includes biological, chemical and physical removal of the phosphorus in both the design phase and ongoing operation of the constructed wetlands system. Several trends in constructed wetlands phosphorus removal are emerging: the primary removal mechanism for phosphorus removal is accretion and new soil sediments, and the use of chemical additives for precipitate and final removal of phosphorus is required for the removal efficiencies required by regulation. The varied applications and results of constructed wetland systems with respect to phosphorus removal are discussed throughout the paper. Floating island technology, using a buoyant material that supports plants, is a newer unique application of constructed wetlands that can be used to remediate wastewater and remove contaminants. Based on the literature search, a series of experiments to further characterize floating islands and improve the removal of phosphorus from wastewater are recommended using this technology.