筛选条件 :
Xiang LI
Tong Wang; Han Wang; Zibin Li; Xiang Li; Gazhit Tsybekmitova; Yayi Wang
WAT. RES.,
2025
268
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EI
SCIE
摘要 : The granular anaerobic ammonium oxidation (anammox) system has attractive advantages in tolerance to environmental-stress and enhancement of nitrogen removal capacity. Sulfide addition can improve nitrogen removals in anammox systems via inducing sulfur denitrification, yet its function in the improvement of the property of anammox granular sludge remains unclear. Herein, we investigated the variations in the morphological and microbial properties of the anammox sludge response to different sulfide concentrations (Na 2 S: 10–100 mg/L) through a long-term experiment. By comparing the sludge diameter and heme c content, it comes that a relatively low sulfide (S/N [nitrate] molar ratio of 0.18–0.50) significantly promoted the average diameter and heme c concentration of sludge by 25–175 % and 75–95 %, respectively, compared to that of both without sulfide addition and a high sulfide addition (S/N > 0.85). This enhancement is primarily because a low amount of sulfide had stimulated the secretion of extracellular polymeric substance, induced slight biogenic sulfur accumulation as microbial nuclei, and facilitated the appropriate amount of filamentous bacteria proliferation. Microbial metabolism functions analyses revealed a robust granular anammox coupled with sulfur denitrification in the sulfide-mediated anammox reactor, and the assembled granules exhibited exceptional tolerance to environmental stress. Significantly, the anammox bacteria ( Candidatus_ Brocadia) dominating the granules displayed satisfactory anammox activity (21.8 ± 2.1 mg N/g VSS h), and their produced nitrate was efficiently removed by the sulfur-oxidizing bacteria ( Thiobacillus ) that predominantly occurred in the flocs. This collaboration ensured an efficient sulfide-mediated anammox granules system, achieving nitrogen removal efficiency exceeding 95 %. These results highlight the function of sulfide in improving the morphological property of anammox sludge as well as the creation of a favorable ecological niche for the functional microorganism, which is important to maintain the efficiency and robustness of the anammox process in treating wastewater.
Xi Cao; Tianqi Liu; Xiang Li; Yong Huang; Qin Nie; Ming Li
Water Research X,
2025
26
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EI
SCIE
摘要 : A full-scale simultaneous partial nitrification, anaerobic ammonia oxidation (anammox), and denitrification (SNAD) reactor was initiated to address the problem of high energy consumption for the treatment of low C/N wastewater. The SNAD system achieved a nitrogen removal rate of 0.9 kg/(m 3 ·d) at an influent NH4 + –N concentration of 500 mg/L after 450 days of stable operation. Partial nitrification was achieved by maintaining free ammonia levels at 0.8 ± 0.3 mg/L and dissolved oxygen concentrations between 0.3 mg/L and 1.2 mg/L, which resulted in synergistic nitrogen removal, with anammox contributing 61 % and denitrification contributing 39 %. Microbiological analyses indicated that the dominant microorganisms were Candidatus Brocadia, Thauera, Denitratisoma, and Nitrosomonas . In conclusion, study provides a solid foundation for the broader implementation of the SNAD process in wastewater treatment systems.
Jiahong Ye; Xiang Li; Yan Yuan; Yayi Wang; Yong Huang; Jun Ma
Journal of Environmental Sciences,
2025
152
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EI
SCIE
摘要 : Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported in successfully operating Anammox systems, and its color is associated with sludge activity. However, in long-term operating systems, AnGS exhibits different sensory colors, physical structures, community structures, and denitrification performance, but the relationship between them has not yet been elucidated. The AnGS of the Anammox system, which has been in operation for more than a decade, can be divided into two main categories: red and white. The specific Anammox activity (SAA) in conventional red AnGS increased continuously as the particle size increased from <0.51 mm to 6.02 ± 0.84 mm. The SAA of white AnGS were slightly lower than those of red AnGS with similarly-size granules but significantly higher than AnGS with smaller red granules. Compared with red AnGS, the extracellular polymeric substances of white AnGS were significantly reduced, mainly due to the higher intracellular iron content, resulting in lower heme c concentration. Thus, heme c may prove not to be an evaluative tool for measuring Anammox activity. Red and white AnGS, whether through self-aggregation or adsorption by hydroxyl apatite and other carriers, will face the fate of internal voids during particle size growth. White AnGS exhibited a more complex microbial community than red AnGS. Candidatus Brocadia was abundant in red AnGS and the abundance increased with increasing granule size. Candidatus Kuenenia and Candidatus Jettenia made significant contributions to denitrification in white AnGS. This study provides a new perspective on particle selection for anammox engineering applications.
Changying Pei; Bolin Li; Xiang Li; Jing Wang; Han Zhang; Xiaoguo Chen
Journal of environmental management,
2024
371
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SCIE
摘要 : Sulfur autotrophic denitrification (SAD) occurs without organic carbon sources, offering advantages in removing nitrogen pollutants from water with low carbon to nitrogen ratio. However, ensuring nitrate–reducing sulfide–oxidizing bacteria ability to access the necessary sulfur and inorganic carbon sources is a challenge. Therefore, this study investigated the feasibility of utilizing a SAD composite filler to mitigate nitrogen and phosphorus pollutants concentrations in secondary effluent of wastewater treatment plants (WWTPs) and reduce eutrophication risk in the receiving water. The use of paraffin optimized composite filler with a satisfying 3.70 % break rate and wear rate without dramatically deteriorating contaminant removal performance. The process achieved 94.26 % total nitrogen (TN) and 90.91 % PO 4 3- -P removal rates in treating synthetic wastewater; and 2.72 ± 1.92 mg/L and 0.29 ± 0.06 mg/L of TN and PO 4 3- -P discharge in treating WWTPs secondary effluent, respectively. The results indicated that denitrification performance of the filler was primarily influenced by variations in NH 4 + -N resulting from SAD and dissimilatory nitrate reduction to ammonia caused by differences in filler composition and preparation factors. Based on the performance difference in SAD, Fe x + leached by H + in the filler changed, affecting phosphorus removal performance. The change in mechanical properties of the filler was primarily dependent on the surface characteristics of the filler and the content/type of the binder. This study demonstrates the feasibility of using SAD for advanced nitrogen and phosphorus removal from wastewater and applying sulfur/siderite integrated composite filler as a pilot, thereby offering insights for the preparation of SAD fillers.
LI Wei; LI Xiang; YUAN Yan; HUANG Yong; FENG Zhen; LI Peng-fei
Zhongguo Huanjing Kexue/China Environmental Science,
2024
44
(11)
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EI
摘要 : In order to solve the problems of low energy recovery rate and high energy consumption of traditional nitrification and denitrification in the treatment of high organic carbon and high ammonia wastewater by the anaerobic internal circulation reactor (IC)-anaerobic aerobic process (AO). Based on partial nitrification/anaerobic ammonia oxidation (PN/A), and IC high-efficiency methanation, complete autotrophic nitrogen removal process (CANON) to treat this kind of wastewater was designed, and the operating characteristics of IC-CANON in the energy recovery and nitrogen removal process were discussed, and the differences between IC-CANON and traditional IC-AO energy recovery, nitrogen removal stability and energy consumption level were evaluated. The results showed that when the C/N of IC effluent was 0.5~1, the nitrogen removal rate (NRR) of the CANON process reached the highest of 0.24kg/(m3·d), the nitrogen removal efficiency (NRE) was (76.2±5)%, and the minimum nitrogen removal contribution rate of Anammox was more than 70%. When influent C/N was 1.9~4, the NRR of first AO reached the highest of 0.14kg/(m3·d), and the NRE was (89.6±0.9)%. When the nitrogen load rate (NLR) of influent fluctuated at 0.22~0.32kg/(m3·d), the minimum contribution rates of CANON process NRE and Anammox remained above 70% and 65%, respectively. When the influent C/N increased to 2.2, the activity of Anammox in CANON was inhibited, and the NRE decreased from 76% to 45.4%. CANON had a strong resistance to NLR impact, but a poor resistance to organic load impact. Under the fluctuations of C/N and NLR of 0.6~6.6kg/(m3·d) and 0.06~0.16kg/(m3·d), the NRE of the first AO remained at about 90%, compared with Canon, the AO process had well resistance to NLR and organic load impact at the same time. When the NRR of the CANON process reached more than 0.21kg/(m3·d), the energy consumption of nitrogen removal is 3.5~3.6kWh/kgN, which can save (77.8±1.8)% compared with the AO process under the same influent and effluent, and the IC energy recovery rate increased from 62.1% to 89.2%.
DANG Peng-ze; TAN Xin-wei; LI Xiang; YUAN Yan; HUANG Yong; LI Peng-fei
Zhongguo Huanjing Kexue/China Environmental Science,
2024
44
(10)
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EI
摘要 : Using actual membrane wastewater as an example, this study explored the dynamic responses of methanogenesis and microbial communities in high-concentration organic nitrogen wastewater under ammonia stress, clarifying the ammonia inhibition threshold, inhibition form, inhibition mechanisms, and response strategies. The results indicate that the primary form of ammonia inhibition in anaerobic digestion (AD) treatment of high-concentration organic nitrogen wastewater is free ammonia (FA), with an inhibition threshold of (145±10) mg/L and a half-maximal inhibitory concentration of (244±10) mg/L. During AD treatment of high-concentration organic nitrogen wastewater, the key methanogenic microorganisms include Methanosaeta (acetotrophic methanogens), Methanomassiliicoccus and Methanomethylovorans (methylotrophic methanogens). The activities of Methanosaeta and Methanomethylovorans decline at ammonia nitrogen levels above 300mg/L and 900mg/L, respectively. Simultaneously, the functional microbes related to hydrogen and carbon dioxide production are inhibited when FA exceeds 140mg/L. This leads to the accumulation of small organic molecules with more than one carbon atom in the system, ultimately resulting in reduced chemical oxygen demand removal efficiency and incomplete release of ammonia nitrogen under high free ammonia (FA) conditions. After severe ammonia inhibition, recovery of the system can be achieved by adjusting the pH, but not through microbial acclimatization.
Miao Shi; Xiang Li; Pengze Dang; Qian Xu; Tianyu Huang; Yan Yuan
Bioresource Technology,
2024
409
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EI
SCIE
摘要 : Understanding the effect of O 2 on the accumulation characteristics of NO 2 − -N and S 0 in the sulfur autotrophic denitrification (DSSADN) system is crucial for enhancing the denitrification efficiency of partial nitrification-anammox using DSSADN. The results revealed that in an environment without O 2 entry, the NO 2 − -N accumulation efficiency (NiAE) and S 0 accumulation efficiency (S 0 AE) of the DSSADN system reached 89.40 % and 93.41 %, respectively. Once system entered O 2, ORP value kept increasing. When ORP increased to −59.9 mV (DO = 0.1 mg/L), soxB and nirK gene expression rose and as well NiAE and S 0 AE continuously decreased to 48.13 % and 29.35 %. When ORP was above 30.9 mV (DO >0.2 mg/L) but below 81.0 mV (DO<0.4 mg/L), narG gene expression reduced and the relatively high sqr gene expression allowed NiAE and S 0 AE remained at 45.08 % and 33.31 %. O 2 promoted the synergistic effect of Thiobacillus and Azoarcus without the proliferation of nitrite oxidizing bacteria.
Tianqi Liu; Jiaweng Guo; Xiang Li; Yan Yuan; Yong Huang; Xiaocheng Zhu
Bioresource Technology,
2024
399
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EI
SCIE
摘要 : The pilot-scale simultaneous denitrification and methanation (SDM)-partial nitrification (PN)-anaerobic ammonia oxidation (Anammox) system was designed to treat anaerobic digestion effluent of kitchen waste (ADE-KW). The SDM-PN was first started to avoid the inhibition of high-concentration pollutants. Subsequently, Anammox was coupled to realize autotrophic nitrogen removal. Shortcut nitrification–denitrification achieved by the SDM-PN. The NO 2 – -N accumulation (92 %) and NH 4 + -N conversion (60 %) were achieved by PN, and the removal of TN and COD from the SDM-PN was 70 % and 73 %, respectively. After coupling Anammox, the TN (95 %) was removed with a TN removal rate of 0.51 kg·m −3 ·d -1 . Microbiological analyses showed a shift from dominance by Methanothermobacter to co-dominance by Methanothermobacter, Thermomonas, and Flavobacterium in SDM during the SDM-PN. While after coupling Anammox, Candidatus kuenenia was enriched in the Anammox zone, the SDM zone shifted back to being dominated by Methanothermobacter . Overall, this study provides new ideas for the treatment of ADE-KW.
Miao Shi; Chen Lv; Peng Wu; Dachao Zhang; Xiang Li; Yong Huang
Journal of Water Process Engineering,
2024
59
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SCIE
摘要 : Exploring the effects of different S/N ratios on the simultaneous accumulation of S 0 and NO 2 − -N in the autotrophic denitrification process is of great significance for the enhanced Anammox denitrification and S 0 resource recovery. The results showed that the low S/N ratio avoided the S 2− accumulated toxicity, and the reactor could be quickly started within 9 days. When S/N ratio was 1, the highest S 0 accumulation efficiency (S 0 AE) and NO 2 − -N accumulation efficiency (NiAE) could be obtained synchronously, which were 77.41 % and 87.83 %, respectively. The production of S 0 and NO 2 − -N was up to 0.57 kg/(m 3 ·d) and 0.18 kg/(m 3 ·d), respectively. Too high or low S/N ratio would affect the S 0 AE and NiAE, respectively. With the increasing S/N ratio, sqr and narG genes expressions were enhanced and soxB and nirK genes expressions were weakened. Thiobacillus, Azoarcus and Pseudaminobacter were the dominant genera performing denitrification and desulphurization in double short-cut sulfur autotrophic denitrification.
GUO Jia-wen; LIN Xin; LI Xiang; HUANG Yong; LIU Tian-qi; ZHAO Wei-dong
Zhongguo Huanjing Kexue/China Environmental Science,
2024
44
(3)
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EI
摘要 : The effects of Fe(III) concentration on nitrogen removal efficiency in Anammox sludge were studied in short-term and long-term. The proper amount of Fe(III) could enhance the nitrogen removal efficiency of Anammox bacteria, 0.09mol/L was the most suitable concentration, the nitrogen removal rate was 0.238kg/(L·d), compared with the control group increased by 14.2%. The nitrogen removal rate was decreased gradually with the influent Fe(III) concentration increased constantly. When the Fe(III) concentration increased to 0.18mol/L, the nitrogen removal rate dropped to 0.215kg/(L·d)decreased by 10.75% compare with 0.09mol/L. The half-saturation constant (KFe) was 0.012mol/L, the inhibiting kinetic constant (KI) was 0.449mol/L obtained by Haldane inhibition kinetic model fitting. The long-term experiment results showed that at 0.09mol/L Fe(III) concentration, the nitrogen removal rate of Anammox increased the fastest, and gradually decreased with the increase of Fe(III) concentration. the conversion ratio of NO2--N and NH4+-N was significantly lower than the theoretical value of 1.32, fluctuate between 1.108 and 1.227, and decreased with the increase of concentration of Fe(III), presumably due to the addition of Fe(III) instead of NO2--N as electron acceptor. Scanning electron microscope results showed that the addition of Fe(III) could make the Anammox bacteria cell structure more stable.