The Treatment of Nitrogenous Wastewater from the Solar-Cell- Manufacturing Process Using a Membrane Bioreactor System
| Autor: | kuo,Yen-chih, 郭彥志 |
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| Rok vydání: | 2016 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 105 In recent years, the rocketing development of industrial manufacturing such as semiconductor or optoelectronic industries in Taiwan has caused a large amount of wastewater being discharged into the environment. Ammonia is one of the main pollutants released from these kinds of wastewater. According to a survey from the Environmental Protection Administration, ammonia containing wastewater from optoelectronic industry and Science Park was 34% of total amount of wastewater produced. Because of its negative impacts on environment such as causing the oxygen depletion and eutrophication phenomenon, ammonia is regulated by Taiwan government and needed to be removed from the wastewater. In 2012, new standard for the ammonia concentration in the effluent from optoelectronic industry and Science Park was released, thus needing an improvement in treating ammonia containing wastewater. The wastewater from optoelectronic industry contains high concentration of ammonia but low concentration of carbon to nitrogen ratio; thus, carbon source is external added during the nitrification and denitrification processes. Among ammonia treatment technologies, membrane bioreactor becomes a candidate for the treatment of ammonia because of its high sludge retention time (SRT), low sludge production and low footprint. This study aims to use O/A/O+MBR process to treat the ammonia containing wastewater from the optoelectronic industry. Herein, the effect of internal carbon source on ammonia removal by O/A/O+MBR system was investigated. In addition, long-term operation of the O/A/O+MBR was observed. During 61 days operation, the average pH of the influent of the nitrification reactor was 9.4, while it was maintained around 6.8 at the effluent after pH adjustment. Oxidation Reduction Potential (ORP) of the reactor was in range of -400 mV - -500mV. Under these conditions, ammonia and nitrate were almost reduced. After denitrification process, the average pH of the reactor was 7.7; therefore, it was appropriate to discharge into the water receiving bodies. The flux of the cross flow MBR remained at 34-38 L/m2-h. The results from this study also found that the ammonia removal was 83% - 98% under low C/N ratio. Under appropriate carbon source addition, the ammonia concentration at the effluent of the bioreactor was lower than 30 mg/L of effluent standard. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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