The purpose of this research was to characterize a flushed dairy manure wastewater and to develop the kinetic and stoichiometric parameters associated with nitrogen removal from the wastewater, as well as to demonstrate experimental and simulated nitrogen removal from the wastewater. The characterization showed that all the wastewaters had carbon to nitrogen ratios large enough for biological nitrogen removal. Analysis of carbon to phosphorus ratios showed that enough carbon is available for phosphorus removal but enough may not be available for both nitrogen and phosphorous removal in anaerobically pretreated wastewater. In addition, kinetic and stoichiometric parameters were determined for the biological nitrogen removal in sequencing batch reactors for the dairy manure wastewater. Results showed that many parameters are similar to those of municipal wastewater treatment systems. This characterization and the derived kinetic and stoichiometric parameters provided some of the information necessary for development of a nitrogen removal process in a sequencing batch reactor. Lab scale treatment of a 1:2 dilution of the anaerobically pretreated wastewater was demonstrated. Treatment was able to achieve between 89 and 93% removal of soluble inorganic nitrogen as well as up to 98% removal of biodegradable soluble and colloidal COD. In addition, a solids removal efficiency of between 79 and 94% was achieved. The lab scale treatment study demonstrated that sequencing batch reactors are capable of achieving high nitrogen removal on wastewaters with the carbon to nitrogen ratios of the dairy manure wastewater. Model simulations of the treatment process were used to develop a sensitivity analysis of the reactor feed configuration as well as the kinetic and stoichiometric parameters. The analysis of the feed configuration demonstrated the advantage of decreasing the amount of feed that is fed in the last feed period so that the effluent nitrate will be minimized. The analysis indicated that the autotrophic growth rate is one of the most important parameters to measure while error in the heterotrophic decay or yield values can lead to miscalculations of oxygen required for treatment. / Master of Science

Over the last two decades, livestock operations have become highly concentrated due to growing trends towards larger, more confined facilities and a decrease in cropland on smaller farms. This has led to greater amounts of excess manure nutrients on farms, increasing the potential for nutrient pollution of water bodies from runoff. The purpose of this study was to determine if enhanced biological phosphorus removal (EBPR) is a viable alternative for managing excess manure nutrients on dairy farms. Assessment of EBPR involved the investigation of various aspects of wastewater treatment modeling and design and farm nutrient management. The fermentation potential (volatile fatty acid (VFA) production) of dairy manure was determined through laboratory analysis to be 15.3% of the total COD. Total VFA production was composed of 57, 23, and 20% acetic, propionic, and butyric acids, respectively. The EBPR component of the BioWin wastewater treatment model was evaluated through a sensitivity analysis. The parameters to which effluent phosphate (PO4) concentration was most sensitive were maximum specific growth rate, growth yield, aerobic PO4 uptake rate per unit poly-b-hydroxybutyrate (PHB) utilized, PHB yield from VFA, PO4 release per unit VFA uptake, and fraction of releasable PO4. An EBPR sequencing batch reactor (SBR) was designed for a dairy farm with 700 lactating cows and 325 ha of corn silage. An economic analysis of EBPR for dairy farms employing P-based manure applications was completed. The cost of hauling excess manure to nutrient deficient farms was the most significant expense in comparing costs of manure management with and without EBPR. For a herd of 700 lactating cows, utilizing EBPR was more economical for farms with 270 ha or less cropland, while EBPR did not offer an economic advantage for farms over 270 ha. / Master of Science