| Summary: | 碩士 === 國立成功大學 === 環境工程學系碩博士班 === 98 === A pilot-scaled AO process treating TFT-LCD wastewater which contaminated with strong nitrogen was evaluated this study. The main point were focus on enhance strategies of anoxic denitrification and oxic nitrification, evaluation of operating parameters and functional indicators and microbial population dynamic with molecular analysis.
In this AO process pilot plan, the volume of anoxic denitrification reactor is 2.4 m3, and the volume of oxic nitrification reactor is 2.7 m3 which is one of the three series reactors. The influent is practical photonic wastewater which TKN/COD ratio is 0.15. In the AO process, nitrate and organic carbon provided anoxic denitrification reaction and organic nitrogen was degraded to ammonia. Ammonia oxidized to nitrate in the oxic nitrification reactors and nitrate was recirculated back to anoxic tank.
During the study, the anoxic denitrification was able to degrade COD efficienctly while adding nitrate in anoxic tank. The Fr/M ratio was 0.142 kg COD/kg-VSS-day after two month enchancement. In addition, the nitrification could convert ammonia to nitrate efficiently with carriers while COD volumetric loading rate was decreased in anoxic tank. The F(NH4+-N)r/M ratio was 0.051 kg NH4+-N/kg-VSS-day in run6.
In this study, the activity of denitrfication with different carbon source were assayed. In the photonic wastewater treatment, the acetic acid, the PI wastewater were better carbon sources The SDNR were 5.32 mg-N/gVSS-hr and 5.92 mg-N/gSS-hr in respectively. The acetone could be utilized as carbon source while incubation in months and the SDNR was 7.44 mg-N/gVSS-hr. In the study, MEA was the main organic carbon source in anoxic tank for denitrifing bacteria. However, TMAH and DMSO could not be degraded by denitrifier as carbon source.
The microbial diversity of ammonia oxidizingbacteria(AOB) was monitored using terminal restriction fragment length polymorphism(T-RFLP). Nitrosomonas europea was dominant AOB in oxic tank. Based on cloning-sequence analysis with the sample taken at day 192 in anoxic tank, Dechloromonas sp. and sulfur oxidation organism were 22% and 12%.
|
|---|
