結合污泥粒徑控制及多重抑制法促進亞硝化反應之研究

The study of promoting nitritation by the combination of controlling particle size of sludge and multiple inhibition methods

倪浩偉(Hao-Wei Ni)

指導教授 ： 簡義杰

淡江大學/工學院/水資源及環境工程學系碩士班/碩士(2022年)

https://doi.org/10.6846/TKU.2022.00226

摘要

穩定抑制亞硝酸鹽氧化菌(nitrite oxidizing bacteria, NOB)是目前達到部分硝化主要的瓶頸之一，有許多研究指出NOB在長期抑制下會產生抗性，導致部分硝化失效。抑制NOB的技術已有許多研究學者做出了實驗結果，目前主流的控制方法有，利用游離氨(Free Ammonia, FA)、游離亞硝酸 (Free Nitrous Acid, FNA)的濃度抑制，或利用低溶氧環境抑制NOB。另外(Kent, et al. 2019)等人對於污泥粒徑影響抑制NOB的效果進行探討，發現 FA/FNA的抑制效果會隨著顆粒變小而增加，其原因為 FA抑制能力受到污泥內部相對擴散阻力的影響，不過目前關於污泥粒 徑影響抑制NOB效果的研究尚鮮少，因此本研究為了進一步探究粒徑和抑制成效的關聯，藉由破碎降低實驗組污泥粒徑(51 μm)與控制組大粒徑污泥(137 μm)進行FA/FNA抑制，並由連續流、硝化活性批次實驗、qPCR驗證抑制效果。
從FA抑制前後硝化活性批次實驗數據顯示，控制組硝酸產生速率(S.NPR)從1.409 mg-N/g VSS-hr下降至0.057 mg-N/g VSS-hr；實驗組從1.386 mg-N/g VSS-hr下降至0.069 mg-N/g VSS-hr，但在後續三週內的平均亞硝酸鹽累積率(NAR)在實驗組為1.54%；控制組為10.72%。由上述抑制實驗結果推測FA確實能短暫抑制NOB活性，但無法使NOB數量下降，在後續三週的觀察中FA對於大粒徑(137 μm)的抑制效果要高於小粒徑(51 μm)。FNA抑制前後硝化活性批次實驗數據顯示，控制組硝酸產生速率(S.NPR)從1.409 mg-N/g VSS-hr下降至0.982 mg-N/g VSS-hr；實驗組從1.386 mg-N/g VSS-hr下降至0.823 mg-N/g VSS-hr，並且在三週內的平均亞硝酸鹽累積率(NAR)在實驗組為87.38%；控制組為78.45%，均非常接近實驗設定之目標值(100%)。綜合上述實驗結果推測，FNA對大粒徑(130 μm)與小粒徑(77 μm)污泥均能有效抑制NOB活性。從FNA抑制後第21天的結果得知，污泥粒徑較小的實驗組亞硝酸鹽累積率(NAR)為94.14%，污泥粒徑較大的控制組硝酸鹽累積率(NAR)為66.62%。在FNA抑制78天後氮系分析結果的知，低粒徑(實驗組)的抑制效果優於不控制粒徑(控制組)，實驗組在FNA抑制後亞硝酸鹽累積率(NAR)在高於80%的狀態下維持了46天，控制組則只維持了14天，從抑制效果的維持時間來看，粒徑確實影響FNA對NOB的抑制成效，且以小粒徑污泥(77 μm)效果優於大粒徑的污泥(130 μm)。本研究成果希望對目前部分硝化瓶頸提供新的解決策略。

關鍵字

部分硝化 ； 污泥粒徑 ； 亞硝酸氧化菌 ； 游離氨 ； 游離亞硝酸

並列摘要

Stable inhibition of nitrite oxidizing bacteria (NOB) is one of the main bottlenecks in achieving partial nitrification. Many studies have pointed out that NOB will develop resistance under long-term inhibition, resulting in partial nitrification failure. Many researchers have made experimental results on NOB inhibition technology. At present, the mainstream control methods are: using Free Ammonia (FA), Free Nitrous Acid (FNA) to inhibit, or using low-soluble Oxygen environment inhibits NOB. In addition (Kent, et al. 2019) et al. discussed the effect of sludge particle size on the NOB inhibition effect, and found that the inhibition effect of FA/FNA increased as the particle became smaller. However, there are few studies on the effect of sludge particle size on NOB inhibition. Therefore, in this study, in order to further explore the relationship between particle size and inhibition effect, the sludge particle size of the experimental group (51 μm) was reduced by crushing. and the control group with large particle size sludge (137 μm) for FA/FNA inhibition, and the inhibition effect was verified by continuous flow, nitrification activity batch experiments, and qPCR.
The batch experimental data of nitrification activity before and after FA inhibition showed that the nitric acid production rate (S.NPR) in the control group decreased from 1.409 mg-N/g VSS-hr to 0.057 mg-N/g VSS-hr; the experimental group decreased from 1.386 mg-N/g VSS-hr decreased to 0.069 mg-N/g VSS-hr, but the mean nitrite accumulation rate (NAR) in the following three weeks was 1.54% in the experimental group and 10.72% in the control group. From the above inhibition experiment results, it is speculated that FA can indeed temporarily inhibit the activity of NOB, but it cannot reduce the bacterial count of NOB. In the following three weeks of observation, the inhibitory effect of FA on the large particle size (137 μm) is higher than that of the small particle size (51 μm). The batch experimental data of nitrification activity before and after FNA inhibition showed that the nitric acid production rate (S.NPR) in the control group decreased from 1.409 mg-N/g VSS-hr to 0.982 mg-N/g VSS-hr; the experimental group decreased from 1.386 mg-N /g VSS-hr to 0.823 mg-N/g VSS-hr, and the mean nitrite accumulation rate (NAR) within three weeks was 87.38% in the experimental group and 78.45% in the control group, both very close to the experimental setting target value (100%). Based on the above experimental results, it is speculated that FNA can effectively inhibit NOB activity on both large particle size (130 μm) and small particle size (77 μm) sludge. From the results on the 21st day after FNA inhibition, the nitrite accumulation rate (NAR) of the experimental group with smaller sludge particle size was 94.14%, and the nitrate accumulation rate (NAR) of the control group with larger sludge particle size was 66.62%. After 78 days of FNA inhibition, nitrogen system analysis results showed that the inhibition effect of low particle size (experimental group) was better than that of uncontrolled particle size (control group), and the nitrite accumulation rate (NAR) of experimental group after FNA inhibition was higher It lasted for 46 days in the state of 80%, and the control group only lasted for 14 days. From the perspective of the maintenance time of the inhibitory effect, the particle size did affect the inhibitory effect of FNA on NOB, and the small particle size sludge (77 μm) is better than the sludge with large particle size (130 μm). The results of this study hope to provide new solutions to some of the current nitrification bottlenecks.

並列關鍵字

Partial Nitrification ； Particle Size ； NOB ； FA ； FNA

參考文獻

參考文獻

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