Show simple item record

dc.contributor.authorWadhawan, Tanush
dc.description.abstractDissolved organic nitrogen (DON) in water and wastewater is a major public concern. In drinking water treatment plants (WTP), DON and biodegradable DON (BDON) may form carcinogenic by-products during disinfection and might also serve as a nutrient for microbiological growth in distribution systems. BDON in treated wastewater can promote algal growth in receiving water bodies. Understanding biodegradability of DON is important to develop strategies and processes capable of minimizing DON impact on the wastewater effluent receiving water bodies and drinking water. WTPs are nutrient-poor oligotrophic systems that receive source water with DON of about ≤2 mg N/L. Wastewater treatment plants (WWTPs) are nutrient-rich eutrophic systems which receive raw wastewater with DON of ≥8 mg N/L. At WWTPs, sidestream deammonification is a highly eutrophic system employed to treat highly concentrated streams of DON (≥100 mg N/L) and ammonia (≥1,500 mg N/L) generated from filtrate from anaerobically digested sludge dewatering. DON characteristics including biodegradability for different trophic levels could differ. The main goal of this dissertation is to investigate biodegradability of DON in these oligotrophic and eutrophic systems. Three research tasks were performed. In the first task, a method to measure BDON in oligotrophic systems was developed and applied to determine the fate of BDON along four treatment stages of a WTP with ozonation prior to filtration. Optimum dose of inocula and incubation time were identified for the BDON measurement. The Moorhead WTP, Moorhead, MN on average removed 30% of DON and 68% of BDON. The second task involved investigating the role of four biological wastewater treatment processes in removing DON from eutrophic systems. Nitrification process biodegraded 70, 54, and 57% of DON in influent, primary effluent, and secondary effluent, respectively. Heterotrophic DON removal was less (1.7 to 38%) while denitrification and deammonification did not remove DON. For the third task, BDON biodegradability in highly eutrophic system was investigated using nitrifying sludge. About 45 to 90% of DON in sidestream effluent was biodegradable. Information from this dissertation provides a better understanding on DON and BDON fate through water and wastewater treatment processes representing different trophic levels.en_US
dc.publisherNorth Dakota State Universityen_US
dc.rightsNDSU Policy 190.6.2
dc.titleInvestigating Biodegradability of Dissolved Organic Nitrogen in Oligotrophic and Eutrophic Systemsen_US
dc.typeDissertationen_US
dc.typeVideoen_US
dc.date.accessioned2018-01-26T22:15:29Z
dc.date.available2018-01-26T22:15:29Z
dc.date.issued2014
dc.identifier.urihttps://hdl.handle.net/10365/27344
dc.subject.lcshBiodegradation.en_US
dc.subject.lcshWater treatment plants.en_US
dc.description.sponsorshipDistrict of Columbia Water and Sewer Authority (DC WASA)en_US
dc.description.sponsorshipDepartment of Civil and Environmental Engineering, North Dakota State Universityen_US
dc.rights.urihttps://www.ndsu.edu/fileadmin/policy/190.pdf
ndsu.degreeDoctor of Philosophy (PhD)en_US
ndsu.collegeEngineeringen_US
ndsu.departmentCivil and Environmental Engineeringen_US
ndsu.programCivil Engineeringen_US
ndsu.advisorKhan, Eakalak


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record