| Abstract | U ovom radu istražen je učinak koncentracije otopljenog kisika (DO) na brzinu autotrofne nitrifikacije u ovisnosti o pH, koncentraciji mikrobne biomase i opterećenja s NH₄-N. Provedeni su diskontinuirani pokusi, pri DO 2 mg/L, DO<1 mg/L i DO>2 mg/L, pri pH 7,3-7,4 i pH 7,9-8,0, te uz 1 g MLSS/L, 2,8 g MLSS/L i 3,8 g MLSS/L. Provedena je autotrofna nitrifikacija 30 mg NH₄-N/L, 50 mg NH₄-N/L i 80 mg NH₄-N/L. U nitrifikaciji 50 mg NH₄-N/L najveća brzina autotrofne nitrifikacije od 19 mg NH₄-N/Lh je postignuta pri DO 2 mg/L i pri pH 7,9-8,0 i s 2,8 g MLSS/L i s 3,8 g MLSS/L. Brzina autotrofne nitrifikacije raste s porastom opterećenja s NH₄-N i pri pH 7,3-7,4 i pri pH 7,9-8,0 za istraženih 30-80 mg NH₄-N/L. Veće brzine autotrofne nitrifikacije se postižu pri pH 7,9-8,0 u usporedbi s pH 7,3-7,4 neovisno o DO. |
| Abstract (english) | In this paper, the effect of dissolved oxygen concentration (DO) on the autotrophic nitrification velocity, depending on the pH, the concentration of microbial biomass (MLSS) and the load with NH₄-N, was studied. Discontinuous experiments were performed at DO 2 mg/L, DO<1 mg/L and DO>2 mg/L at pH 7.3-7.4 and pH 7.9-8.0 and with 1 g MLSS /L, 2.8 g MLSS/L and 3.8 g MLSS/L. Autotrophic nitrification of 30 mg NH₄-N/L, 50 mg NH₄-N/L and 80 mg NH₄-N/L was performed. In the nitrification of 50 mg NH₄-N/L, the maximum autotrophic nitrification rate of 19 mg NH₄-N/Lh was reached at DO 2 mg/L and at pH 7.9-8.0 and 2.8 g MLSS/L and with 3.8 g MLSS/L. The rate of autotrophic nitrification increases with the increase in loading with NH₄-N and at pH 7.3-7.4 and at pH 7.9-8.0 for the investigated 30-80 mg NH₄-N/L. Greater autotrophic nitrification rates are achieved at pH 7.9-8.0 compared to the pH 7.3-7.4 irrespective of DO. |
