Nitrous oxide production pathway and its regulation strategy in Anammox system

doi:10.16085/j.issn.1000-6613.2024-0638

Abstract

Abstract:

Anaerobic ammonium oxidation (Anammox) system is considered one of the most promising low C/N wastewater treatment technologies due to its high efficiency and low energy consumption in the nitrogen removal process. However, with the exacerbation of global warming and the proposal of the national "two-carbon" strategy, the problem of a large number of strong greenhouse gases (N₂O) released by Anammox system during the nitrogen removal process has gradually become a bottleneck restricting the application of the system in the field of depth nitrogen removal for wastewater. Based on existing research findings, this article first sorted out the N₂O production pathway of the Anammox system and comprehensively discussed the impact factors and regulation strategies on potential N₂O producing enzymes, strains, and their yields. The results showed that although N₂O production in Anammox system could be controlled by these methods, they might lead to instability of nitrogen removal function and even secondary pollution. Considering that the characteristics of the colony structure distribution within the Anammox system is an internal factor directly affecting N₂O yield and nitrogen removal effectiveness, this article proposed combining immobilization method of embedding simultaneously AnAOB bacteria and "hybrid bacteria" inhibitor within the Anammox system, and suggested using the simulation functions of activated sludge mathematical model and modern molecular biological methods to deeply understand the changes of N₂O generation kinetics in the coupling technology as well as the potential succession rules of N₂O generating bacteria, in order to provide a scientific foundation for developing an efficient nitrogen removal of the Anammox system suitable for carbon emission reduction.

Key words: Anammox system, nitrous oxide, biological nitrogen removal, partial nitritation, bacterial succession

摘要：

厌氧氨氧化系统（Anammox system）凭借其高效低耗的脱氮功能，被认为是较具应用潜力的低C/N污水处理技术之一。随着全球气候变暖趋势的加重和国家“双碳”战略的提出，Anammox系统在脱氮过程中释放的大量强温室气体（N₂O）问题，逐渐成为限制该系统在污水深度脱氮领域应用的瓶颈。基于现有的研究成果，首先对Anammox系统的N₂O产生途径进行梳理，并综合论述了影响因素和调控策略对潜在产生N₂O的酶、菌种及其产量的影响，发现虽然现有的方法能够控制Anammox系统的N₂O产量，但是容易导致脱氮功能失稳，甚至引发二次污染问题。考虑到Anammox系统的菌落结构分布特征是直接影响N₂O产量和脱氮效果的内因，提出采用同时包埋了AnAOB菌和“杂菌”抑制剂的固定化技术与Anammox系统耦合的工艺，并建议借助活性污泥数学模型的仿真功能和现代分子生物学手段以深入认识耦合技术的N₂O生成过程的动力学变化和潜在产生N₂O的菌种演替的规律，为构建适用于碳减排的高效型Anammox脱氮工艺提供科学的指导依据。

关键词: 厌氧氨氧化系统, 氧化亚氮, 生物脱氮, 亚硝化, 菌群演替

CLC Number:

X703.5

GAO Feng, WANG Chongyang, GAO Sheng, ZHANG Yahong, CHEN Tao, NIAN Zheng. Nitrous oxide production pathway and its regulation strategy in Anammox system[J]. Chemical Industry and Engineering Progress, 2025, 44(6): 3579-3591.

高峰, 王重阳, 高升, 张雅泓, 陈涛, 年正. Anammox系统的氧化亚氮产生途径及调控[J]. 化工进展, 2025, 44(6): 3579-3591.

Figures/Tables 6

温度/℃	进水TN浓度/mg·L^-1	N₂O浓度/mg·L^-1	N₂O积累速率/mg·L^-1·min^-1	（N₂O/ΔTN）/%
20	80	0.380	0.002	0.46
	120	0.811	0.003	0.68
	240	1.086	0.003	0.95
25	80	0.444	0.003	0.59
	120	0.854	0.004	0.91
	240	1.584	0.005	1.11
35	80	0.500	0.012	0.85
	120	1.563	0.019	1.43
	240	2.424	0.026	1.42

工艺类型	曝气速率/mL·min^-1	N₂O产量控制策略	N₂O产生速率	（N₂O/TN）/%	参考文献
PN-A-UASB	—	以出水水质为约束条件，采用连续曝气法，曝气时间不大于60min	0.050g/(L·d) （在高曝气强度下）	2.5	[37]
PN-A-UASB	—	以出水水质为约束条件，采用连续曝气法，曝气时间不大于60min	0.029g/(L·d) （在低曝气强度下）	1.0	[37]
PN-A-SBR	—	缩短每周期工艺运行时间，将时间由480min减少至160min，并调节曝气装置启停为每周期2次	0.23mg/(g·h)	1.1	[57]
	从1250降低至417	在不影响氨氧化反应的同时，将短程硝化的DO浓度控制在1.2mg/L以下，以抑制NOB活性	—	0.016~0.44	[39]
	从1500降低至300	为处理厌氧消化液，将曝气时间控制在10~30min	—	0.95	[5]
	从50降低至30	采用高效的曝气装置，以增大曝气扩散系数，使其系数值不低于11.4h^-1	0.003g/(L·d)	0.39~0.59	[9]
	150	联用低曝气速率（150mL/min）和间歇式投加NO₂^-，以提高AnAOB活性		0.98	[4]
段式PN-A	从650降低至100	联用低曝气速率和低进水氮负荷	—	4.0（PN段），0.1（A段）	[14]

反应过程动力学	反应速率方程
包含NH₂OH的自养菌好氧生长	$η A O B q A O B, O S O K A O B, O + S O ⋅ S N H 2 O H K A O B, N H 2 O H + S N H 2 O H X A O B$
自养反硝化型AOB生长	$η A O B, N O q A O B, O K A O B, O K A O B, O + S O ⋅ S N H 2 O H K A O B, N H 2 O H + S N H 2 O H ⋅ S N O 2 K A O B, N O 2 + S N O 2 X A O B$
内源性反硝化型异养菌生长	$μ H, E P S, N O K H, O K H, O + S O ⋅ S N O 2 K H, N O 2 + S N O 2 ⋅ X E P S / X H K E P S + X E P S / X H ⋅ K S T O K S T O + X S T O ⋅ K S K S + S S X H$
反硝化中N₂O还原为N₂过程	$μ H, S T O, N O K H, O K H, O + S O ⋅ S N 2 O K H, N 2 O + S N 2 O ⋅ X S T O / X H K S T O + X S T O / X H ⋅ K S K S + S S X H$

反应过程动力学	反应速率方程
包含NH₂OH的自养菌好氧生长	$η A O B q A O B, O S O K A O B, O + S O ⋅ S N H 2 O H K A O B, N H 2 O H + S N H 2 O H X A O B$
自养反硝化型AOB生长	$η A O B, N O q A O B, O K A O B, O K A O B, O + S O ⋅ S N H 2 O H K A O B, N H 2 O H + S N H 2 O H ⋅ S N O 2 K A O B, N O 2 + S N O 2 X A O B$
内源性反硝化型异养菌生长	$μ H, E P S, N O K H, O K H, O + S O ⋅ S N O 2 K H, N O 2 + S N O 2 ⋅ X E P S / X H K E P S + X E P S / X H ⋅ K S T O K S T O + X S T O ⋅ K S K S + S S X H$
反硝化中N₂O还原为N₂过程	$μ H, S T O, N O K H, O K H, O + S O ⋅ S N 2 O K H, N 2 O + S N 2 O ⋅ X S T O / X H K S T O + X S T O / X H ⋅ K S K S + S S X H$

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