Nitrit kao akceptor elektrona u denitrifikaciji

master's thesis

• Title (english): Nitrite as an electron acceptor in denitrification
• Author: Mihaela Frketić
• Mentor: Dijana Grgas (mentor)
• Committee member: Tibela Landeka Dragičević (predsjednik povjerenstva)
• Committee member: Tonči Rezić (član povjerenstva)
• Committee member: Antonija Trontel (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for the Biological Waste Water Treatment); Zagreb
• Defense date and country: 2023-12-20, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Uklanjanje dušika iz otpadne vode preko nitrita (denitritacija) pruža prednosti u usporedbi s denitrifikacijom. U ovom radu istražena je denitritacija korištenjem visoke početne koncentracije nitrita, 70 ± 5 mg NO₂-N/L. Pokusi su vođeni u anoksičnim uvjetima pri 3 ± 0,2 g MLSS (engl. Mixed Liquor Suspended Solids, MLSS, hrv. Suspendirane čestice miješane tekućine)/L dok je kao izvor ugljika korišten acetat pri omjerima C/N (ugljik/dušik) 1, 2, 3 i 4. Praćene su promjene vrijednosti KPK (Kemijska potrošnja kisika), nitrita, slobodne nitritne kiseline, nitrata, pH vrijednosti, temperature, koncentracije otopljenog kisika. Izračunate su brzine uklanjanja nitrita i KPK te omjer utrošene količine KPK za redukciju nitrita. Omjeri C/N 1 i 2 rezultirali su nepotpunom denitritacijom, uklonjeno je 46,5 % i 83,6 % nitrita zbog limitacije elektron donorima (organskim sastojcima), dok je pri omjerima C/N 3 i 4 postignuta potpuna denitritacija. Raspon vrijednosti unutar kojeg se kretala brzina redukcije nitrita pri svim ispitanim omjerima C/N iznosi 26,4 – 27,6 mg NO₂-N/Lh.

Abstract (english)

The removal of nitrogen from wastewater via nitrite offers advantages compared to denitrification. In this work, denitritation was investigated using a high initial concentration of nitrite, 70 ± 5 mg NO₂-N/L. The experiments were conducted under anoxic conditions at 3 ± 0.2 g MLSS/L, while acetate was used as a carbon source at C/N ratios of 1, 2, 3 and 4. Changes in COD values, nitrite, free nitrous acid, nitrate, pH value, temperature, dissolved oxygen were monitored. Removal rates of nitrite and COD, and the ratio of the amount of COD used for nitrite reduction, were calculated. C/N ratios of 1 and 2 resulted in incomplete denitritation due to limitation of electron donor (organics), 46.5% and 83.6% of nitrite was removed, while complete denitritation was achieved at C/N ratios of 3 and 4. The achieved nitrite reduction rates at all C/N ratios were in the range 26.4 – 27.6 mg NO₂-N/Lh.

• Keywords: denitritacija; acetat; C/N omjer; nitrit
• Keywords (english): denitritation; acetate; C/N ratio; nitrit
• Language: croatian
• URN:NBN: urn:nbn:hr:159:340653
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-05-28 12:46:56