結合部分硝化、厭氧氨氧化及脫硝程序 於處理養豬場之厭氧出流廢水

Abstract

結合部分硝化與厭氧氨氧化及脫硝程序 (Simultaneous partial Nitrification, Anammox and Denitrification, 簡稱SNAD) 為一厭氧氨氧化 (Anammox) 相關程序。SNAD程序自2009年開始發展，做為處理廢水之用途。其特性為三種細菌共存於同一系統 (氨氧化菌、厭氧氨氧化菌以及脫硝菌)，使SNAD程序可同時去除廢水中氮化合物與有機碳。本篇的研究方向為應用SNAD程序於養豬場之厭氧出流廢水並探討其處理成效。實驗規劃為在15-30oC的環境溫度下，設置一實驗室規模的5公升序批次反應槽，發展SNAD程序以處理養豬場之厭氧出流廢水(Anaerobic Digester Liquor of Swine Wastewater, 簡稱ADLSW)。 由於ADLSW水質之變動(COD: 387±145 mg/L; TKN: 662±189 mg/L; NH4+-N: 519±134 mg/L; alkalinity: 3036±1036 mg/L as CaCO3)與環境溫度的影響，導致SNAD程序操作不穩定。在本篇研究裏，藉由氨轉換率Y(NO2-+ NO3-)/ NH4+的計算與討論，以期提高SBR-5處理成效，調整氣體流量可將Y(NO2-+ NO3-)/ NH4+移至較佳的數值。實驗中，採取饋料批次進流方式，使得SNAD朝向穩定操作發展，並克服有機氮所導致的負面影響。在饋料批次進流操作、氮負荷量155 g/m3 d和有機碳負荷量153 g/m3 d條件下，第472到553天SNAD達到穩定的操作狀況。此階段總氮與COD去除效率分別為74和73%。 研究結果顯示ADLSW裏所含的有機氮、進流方式、溶氧程度(DO)與反應槽溫度會影響SNAD程序之處理成效。

SNAD (Simultaneous partial Nitrification, Anammox and Denitrification) is an Anammox based process developed in 2009 to treat wastewater. SNAD is able to remove organic carbon along with nitrogen from wastewater as three microbial communities (Ammonium oxidizing bacteria, Anammox bacteria and denitrifiers) exist in this system. The aim of this research was to apply SNAD process on anaerobic digester liquor of swine wastewater (ADLSW) treatment, and investigate its performance. A lab scale 5 L sequencing batch reactor (SBR) was set up for the establishment of SNAD process to treat ADLSW under ambient temperature (15-30oC). The fluctuation of ADLSW quality (COD: 387±145 mg/L; TKN: 662±189 mg/L; NH4+-N: 519±134 mg/L; alkalinity: 3036±1036 mg/L as CaCO3) and ambient temperature led to unstable SNAD operation. The conversion ratio of Y(NO2-+ NO3-)/ NH4+ was calculated and discussed for improving performance in SBR-5. The adjustment of air flow rate would shift the favorable value of Y(NO2-+ NO3-)/ NH4+.. Fed batch feeding strategy was applied to have stable condition and overcome the negative effect of organic nitrogen. Under fed batch mode of feeding, steady state conditions were achieved in the SBR-5 at NLR and OLR of 155 g/m3 d and 153 g/m3 d, respectively between days 472 to 553. The total nitrogen and COD removal efficiencies were 74 and 73%, respectively in this phase. The results showed that presence of organic nitrogen in ADLSW, feeding strategy, dissolved oxygen (DO) and reactor temperature affected the SNAD process.