結合部分硝化與厭氧氨氧化程序應用於半導體產業廢水

Abstract

本研究的目的主要是利用部分硝化與厭氧氨氧化程序(CANON程序)於單一反應槽來觀察處理半導體廢水的可行性，以及處理含半導體產業主要氮污染物質TMAH (Tetramethylammonium hydroxide)之合成廢水對CANON程序的影響。在進行長期TMAH對CANON程序的影響之試驗前，會先利用批次試驗來觀察TMAH對於anammox即時的影響，最後發現其半抑制濃度為307 mg/L。半導體廢水及含半導體產業主要含氮污染物質之合成廢水分別利用總體積1000 L模廠規模以及實驗室規模18 L的反應槽(SBR-18)進行處理。為了啟動CANON程序，SBR-18前246天利用不含TMAH的合成廢水來進行實驗，等啟動完畢，接下來的147天再慢慢添加不同濃度的TMAH(33-1000 mg/L)來觀察TMAH對CANON程序長期的影響，最後發現整個系統的總氮去除率、有機氮去除率和TMAH去除率分別為95、77以及100%，此外本實驗發現添加TMAH後在系統當中有明顯的脫硝反應。處理半導體廢水的模廠試驗總共進行了550天，實驗結果發現含高氨氮濃度的半導體廢水(氨氮濃度高於2500 mg/L)是可以利用CANON程序來處理，在總氮負荷率為665 g/m3-d的條件下其氨氮去除率以及總氮去除率分別為85和75%。

The real semiconductor industrial wastewater and the synthetic wastewater containing major solvent, TMAH (Tetramethylammonium hydroxide, a major solvent used in semiconductor industry), were treated by single-staged partial nitrification and Anammox process i.e CANON (Completely Autotrophic Nitrogen Removal over Nitrite). A pilot scale sequencing batch reactor (SBR) with total volume of 1 m3 was used to study the treatment of real semiconductor wastewater by CANON process. An 18 L lab scale SBR (SBR-18) was set-up to develop CANON process using synthetic wastewater to study the long-term effect of TMAH (33 to 1000 mg/L) on reactor performance. Besides, the short-term effect of TMAH on anammox was evaluated by batch tests before studying the long-term effect of TMAH on CANON process in lab scale SBR. The pilot scale SBR and SBR-18 were operated for 550 and 392 days, respectively. The results of batch tests suggest that TMAH had an inhibitory effect on anammox activity. The IC50 of TMAH was found to be 307 mg/L in batch tests. To study the long-term effect of TMAH on CANON process, SBR-18 was initially fed with synthetic wastewater (day 1 to 246), where influent ammoniuim nitrogen increased gradually from 400 to 850 mg/L. Later, the sysnthtic wastewater was spiked with TMAH and fed to SBR-18. The concentraion of TMAH in wastewater was gradually increased from 33 to 1000 mg/L. At 1000 mg/L of TMAH in influent, the SBR-18 could remove 95, 77, and 100% of TN, org-N and TMAH, respectively . The results of SBR-18 suggested that denitrification reaction also occurred in the CANON system. In the pilot scale CANON reactor, the raw wastewater has been able to treat semiconductor wastewater with high ammonia concentration (above 2500 mg/L). The NH4+-N and TN efficiency at NLR of 665 g/m3-d were 85 and 75%, respectively.