1
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Zhao H, Guo Y, Wang X, Sun H, Gao M, Wu C, Li S, Li YY, Wang Q. Exploring the maximum nitrite production rate through the granular sludge-type reactor to match the needs of anammox process realizing efficient nitrogen removal. ENVIRONMENTAL RESEARCH 2024; 255:119158. [PMID: 38763279 DOI: 10.1016/j.envres.2024.119158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 05/21/2024]
Abstract
The reliable and efficient nitrite production rate (NPR) through nitritation process is the prerequisite for the efficient running of subsequent processes, like the anammox process and the nitrite shunt. However, there has been scant research on stable and productive nitritation process in recent years. In this study, at a stable hydraulic retention time of 12.0 h and with precise and strict DO control, the upper limit of the NPR was initially investigated using a continuous-flow granular sludge reactor. The NPR of 1.69 kg/m3/d with a nitrite production efficiency of 81.97% was finally achieved, which set a record until now in similar research. The median sludge particle size of 270.0 μm confirmed the development of clearly defined granular sludge. The genus Nitrosomonas was the major ammonium oxidizing bacteria. In conclusion, this study provides valuable insights for the practical application of the effective nitritation process driving subsequent nitrogen removal processes.
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Affiliation(s)
- Hongjun Zhao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yan Guo
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, Beijing, 100083, China.
| | - Xiaona Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, Beijing, 100083, China
| | - Haishu Sun
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Shunde Innovation School, University of Science and Technology Beijing, Foshan, 528399, China
| | - Ming Gao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, Beijing, 100083, China
| | - Chuanfu Wu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, Beijing, 100083, China
| | - Shuang Li
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yu-You Li
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8579, Japan
| | - Qunhui Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, Beijing, 100083, China
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2
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Gao M, Guo B, Zou X, Guo H, Yao Y, Chen Y, Guo J, Liu Y. Mechanisms of anammox granular sludge reactor effluent as biostimulant: Shaping microenvironment for anammox metabolism. BIORESOURCE TECHNOLOGY 2024; 406:130962. [PMID: 38876278 DOI: 10.1016/j.biortech.2024.130962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 06/01/2024] [Accepted: 06/11/2024] [Indexed: 06/16/2024]
Abstract
Effluent from anammox granular sludge (AnGS) bioreactor contains microbes and microbial products. This study explored mechanisms of utilizing AnGS-effluent as biostimulant for anammox process enhancement. Compared with no AnGS-effluent supplemented control reactor, 5.0 and 1.3 times higher ammonium nitrogen and total inorganic nitrogen removal rates, respectively were obtained with continuous AnGS-effluent supplementation after 98 days' operation. Anammox bacteria from Candidatus Brocadia accounted for 0.1 % (DNA level) and 1.3 %-1.5 % (RNA level) in control reactor, and 2.9 % (DNA level) and 54.5 %-55.4 % (RNA level) in the AnGS-effluent-fed reactor. Influent microbial immigration evaluation showed that bacterial immigration via AnGS-effluent supplementation was not the main contributor to active anammox community development. Amino acids biosynthesis, B-vitamins and coenzymes metabolism related pathways were facilitated by AnGS-effluent supplementation. AnGS-effluent supplementation aided anammox metabolic activity by shaping microenvironment and microbial interactions. This study provides insights into enhancing anammox bacterial metabolism with AnGS-effluent microbial products as biostimulant.
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Affiliation(s)
- Mengjiao Gao
- College of Environment and Ecology, Chongqing University, Chongqing 400044, China; Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Bing Guo
- Centre for Environmental Health and Engineering (CEHE), School of Sustainability, Civil and Environmental Engineering, University of Surrey, Guildford GU2 7XH, UK
| | - Xin Zou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada; School of Civil & Environmental Engineering, Queensland University of Technology, Brisbane QLD 4001, Queensland, Australia
| | - Hengbo Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yiduo Yao
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Youpeng Chen
- College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Jinsong Guo
- College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada; School of Civil & Environmental Engineering, Queensland University of Technology, Brisbane QLD 4001, Queensland, Australia.
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3
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Trebuch LM, Timmer J, Graaf JVD, Janssen M, Fernandes TV. Making waves: How to clean surface water with photogranules. WATER RESEARCH 2024; 260:121875. [PMID: 38875855 DOI: 10.1016/j.watres.2024.121875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 05/11/2024] [Accepted: 06/02/2024] [Indexed: 06/16/2024]
Abstract
Global surface waters are in a bad ecological and chemical state, which has detrimental effects on entire ecosystems. To prevent further deterioration of ecosystems and ecosystem services, it is vital to minimize environmental pollution and come up with ways to keep surface water healthy and clean. Recently, photogranules have emerged as a promising platform for wastewater treatment to remove organic matter and nutrients with reduced or eliminated mechanical aeration, while also facilitating CO2 capture and production of various bioproducts. Photogranules are microbial aggregates of microalgae, cyanobacteria, and other non-phototrophic organisms that form dense spheroidic granules. Photogranules settle fast and can be easily retained in the treatment system, which allows increased amounts of water and wastewater to be treated. So far, photogranules have only been tested on various "high-strength" wastewaters but they might be an excellent choice for treatment of large volumes of polluted surface water as well. Here, we propose and tested for the first time photogranules on their effectiveness to remove nutrients from polluted surface water at unprecedented low concentrations (3.2 mg/L of nitrogen and 0.12 mg/L of phosphorous) and low hydraulic retention time (HRT = 1.5 h). Photogranules can successfully remove nitrogen (<0.6 mg/L, ∼80 % removal) and phosphorous (<0.01 mg/L, 90-95 % removal) to low levels in sequencing batch operation even without the need for pH control. Subjecting photogranules to surface water treatment conditions drastically changed their morphology. While, under "high-strength" conditions the photogranules were spherical, dense and defined, under polluted surface water conditions photogranules increased their surface area by forming fingers. However, this did not compromise their excellent settling properties. Finally, we discuss the future perspectives of photogranular technology for surface water treatment.
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Affiliation(s)
- Lukas M Trebuch
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10 PB, Wageningen 6708, the Netherlands.
| | - Jolieke Timmer
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10 PB, Wageningen 6708, the Netherlands
| | - Jan van de Graaf
- Waterboard De Dommel, Bosscheweg 56 WB, Boxtel 5283, the Netherlands
| | - Marcel Janssen
- Bioprocess Engineering, AlgaePARC Wageningen University, P.O. Box 16 AA, Wageningen 6700, the Netherlands
| | - Tânia V Fernandes
- Department Water Supply, Sanitation and Environmental Engineering, IHE Delft Institute for Water Education, Westvest 7, Delft 2611 AX, The Netherlands; Environmental Technology, Wageningen University, PO Box 8129, Wageningen 6700 EV, The Netherlands
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4
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Dong T, Zhang L, Hao S, Yang J, Peng Y. Interspecies cooperation-driven photogenerated electron transfer processes and efficient multi-pathway nitrogen removal in the g-C 3N 4-anammox consortia biohybrid system. WATER RESEARCH 2024; 255:121532. [PMID: 38564893 DOI: 10.1016/j.watres.2024.121532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 03/18/2024] [Accepted: 03/26/2024] [Indexed: 04/04/2024]
Abstract
Photocatalytic materials-microbial biohybrid systems pave the way for solar-driven wastewater nitrogen removal. In this study, interspecies cooperation in photogenerated electron transfer and efficient nitrogen removal mechanism in the g-C3N4-anammox consortia biohybrid system were first deciphered. The results indicated that the essential extracellular electron carriers (cytochrome c and flavin) for anammox genomes were provided by associated bacteria (BACT3 and CHLO2). This cooperation, regulated by the ArcAB system and electron transfer flavoprotein, made anammox bacteria the primary photogenerated electron sink. Furthermore, an efficient photogenerated electron harness was used to construct a reductive glycine pathway (rGlyP) in anammox bacteria inventively, which coexisted with the Wood-Ljungdahl pathway (WLP), constituting a dual-pathway carbon fixation model, rGlyP-WLP. Carbon fixation products efficiently contributed to the tricarboxylic acid cycle, while inhibiting electron diversion in anabolism. Photogenerated electrons were targeted channeled into nitrogen metabolism-available electron carriers, enhancing anammox and dissimilatory nitrate reduction to ammonium (DNRA) processes. Moreover, ammonia assimilation by the glycine cleavage system in rGlyP established an alternative ammonia removal route. Ultimately, multi-pathway nitrogen removal involving anammox, DNRA, and rGlyP achieved 100 % ammonia removal and 94.25 % total nitrogen removal efficiency. This study has expanded understanding of anammox metabolic diversity, enhancing its potential application in carbon-neutral wastewater treatment.
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Affiliation(s)
- Tingjun Dong
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing, 100124, China
| | - Li Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing, 100124, China.
| | - Shiwei Hao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing, 100124, China
| | - Jiachun Yang
- China Coal Technology & Engineering Group Co. Ltd., Tokyo, 100-0011, Japan
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing, 100124, China
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5
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Zheng R, Feng Y, Kong L, Wu X, Zhou J, Zhang L, Liu S. Blue-light irradiation induced partial nitrification. WATER RESEARCH 2024; 254:121381. [PMID: 38442606 DOI: 10.1016/j.watres.2024.121381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 12/08/2023] [Accepted: 02/24/2024] [Indexed: 03/07/2024]
Abstract
The role of ray radiation from the sunlight acting on organisms has long-term been investigated. However, how the light with different wavelengths affects nitrification and the involved nitrifiers are still elusive. Here, we found more than 60 % of differentially expressed genes (DEGs) in nitrifiers were observed under irradiation of blue light with wavelengths of 440-480 nm, which were 13.4 % and 20.3 % under red light and white light irradiation respectively. Blue light was more helpful to achieve partial nitrification rather than white light or red light, where ammonium oxidization by ammonia-oxidizing archaea (AOA) with the increased relative abundance from 8.6 % to 14.2 % played a vital role. This was further evidenced by the enhanced TCA cycle, reactive oxygen species (ROS) scavenge and DNA repair capacity in AOA under blue-light irradiation. In contrast, nitrite-oxidizing bacteria (NOB) was inhibited severely to achieve partial nitrification, and the newly discovered encoded blue light photoreceptor proteins made them more sensitive to blue light and hindered cell activity. Ammonia-oxidizing bacteria (AOB) expressed genes for DNA repair capacity under blue-light irradiation, which ensured their tiny impact by light irradiation. This study provided valuable insights into the photosensitivity mechanism of nitrifiers and shed light on the diverse regulatory by light with different radiation wavelengths in artificial systems, broadening our comprehension of the nitrogen cycle on earth.
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Affiliation(s)
- Ru Zheng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Yiming Feng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Lingrui Kong
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Xiaogang Wu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Jianhang Zhou
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Liguo Zhang
- School of Environmental and Resource Sciences, Shanxi University, Taiyuan, 030006, China.
| | - Sitong Liu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China.
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6
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Yang Z, Wang X, Yu D, Chen G, Ma K, Zhang P, Xu Y. Granulation characteristics of anammox sludge in response to different signal-molecule-stimulants; mediated through programmed cell death. CHEMOSPHERE 2024; 354:141497. [PMID: 38452981 DOI: 10.1016/j.chemosphere.2024.141497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 01/23/2024] [Accepted: 02/16/2024] [Indexed: 03/09/2024]
Abstract
During the anammox process, mitigation of biomass washout to increase sludge retention is an important parameter of process efficiency. Signal molecular stimulants (SMS) initiate the sludge granulations controlled by programmed cell death (PCD) of microorganisms. In this study, the aerobic granular sludge (AGS), cell fragments, extracellular polymeric substances (EPS), and AGS process effluent were tested as SMS to identify their effect on anammox granulation. The results showed that the addition of SMS increased the nitrogen removal efficiency to varying degrees, whereas the addition of AGS process supernatant, as SMS, increased the ammonia removal efficiency up to 96%. The addition of SMS was also found to increase EPS production and contributed to sludge granulation. In this process, the proportion of PCD increased and both Gaiella and Denitratisoma abundance increased from 3.54% to 5.59%, and from 1.8% to 3.42%, respectively. In conclusion, PCD was found important to increase anaerobic ammonia oxidation performance through the granulation mechanism.
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Affiliation(s)
- Zifeng Yang
- School of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, PR China
| | - Xueping Wang
- Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 311121, PR China
| | - Deshuang Yu
- School of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, PR China
| | - Guanghui Chen
- School of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, PR China; Carbon Neutrality and Eco-Environmental Technology Innovation Center of Qingdao, Qingdao, 266071, PR China.
| | - Kang Ma
- Qingdao Licun River Sewage Treatment Plant, Qingdao, 266000, PR China
| | - Peiyu Zhang
- School of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, PR China
| | - Yanmin Xu
- School of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, PR China
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7
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Tang L, Gao M, Liang S, Wang S, Wang X. Enhanced biological phosphorus removal sustained by aeration-free filamentous microalgal-bacterial granular sludge. WATER RESEARCH 2024; 253:121315. [PMID: 38382289 DOI: 10.1016/j.watres.2024.121315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 01/30/2024] [Accepted: 02/13/2024] [Indexed: 02/23/2024]
Abstract
The microalgal-bacterial granular sludge (MBGS) based enhanced biological phosphorus removal (EBPR) (MBGS-EBPR) was recently proposed as a sustainable wastewater treatment process. Previous work showed the possibility of obtaining an MBGS-EBPR process starting from mature MBGS and phosphate-accumulating organisms (PAOs) enriched aerobic granular sludge (AGS) and validated the effectiveness of removing carbon/nitrogen/phosphorus with mechanical aeration. The present work evaluated whether the same could be achieved starting from conventional activated sludge and operating under aeration-free conditions in an alternating dark/light photo-sequencing batch reactor (PSBR). We successfully cultivated filamentous MBGS with a high settling rate (34.5 m/h) and fast solid-liquid separation performance, which could be attributed to the proliferation of filamentous cyanobacteria and stimulation of extracellular polymeric substances (EPS) production. The process achieved near-complete steady-state removal of carbon (97.2 ± 1.9 %), nitrogen (93.9 ± 0.7 %), and phosphorus (97.7 ± 1.7 %). Moreover, improved phosphorus release/uptake driven by photosynthetic oxygenation under dark/light cycles suggests the enrichment of PAOs and the establishment of MBGS-EBPR. Batch tests showed similar phosphorus release rates in the dark but significantly lower phosphorus uptake rates in the presence of light when the filamentous granules were disrupted. This indicates that the filamentous structure of MBGS has minor limitations on substrate mass transfer while exerting protective effects on PAOs, thus playing an important role in sustaining the function of aeration-free EBPR. Microbial assays further indicated that the enrichment of filamentous cyanobacteria (Synechocystis, Leptoolybya, and Nodosilinea), putative PAOs and EPS producers (Hydrogenophaga, Thauera, Flavobacterium, and Bdellovibrio) promoted the development of filamentous MBGS and enabled the high-efficient pollutant removal. This work provides a feasible and cost-effective strategy for the startup and operation of this innovative process.
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Affiliation(s)
- Liaofan Tang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Mingming Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Shuang Liang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Shuguang Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China; Weihai Research Institute of Industrial Technology of Shandong University, Weihai, 264209, China
| | - Xinhua Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China.
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8
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Chen J, Liu X, Lu T, Liu W, Zheng Z, Chen W, Yang C, Qin Y. The coupling of anammox with microalgae-bacteria symbiosis: Nitrogen removal performance and microbial community. WATER RESEARCH 2024; 252:121214. [PMID: 38301528 DOI: 10.1016/j.watres.2024.121214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 01/21/2024] [Accepted: 01/26/2024] [Indexed: 02/03/2024]
Abstract
The partial nitrification-anammox process for ammonia nitrogen wastewater treatment requires mechanical aeration to provide oxygen, which is not conducive to energy saving. The microalgae-bacteria symbiotic system (MaBS) has the advantages of low carbon and energy saving in wastewater biological nitrogen removal. Therefore, this study combined the MaBS with an anammox process to provide oxygen, through the photosynthesis of microalgae instead of mechanical aeration. We investigated the nitrogen removal efficiency and long-term operation of a co-culture system comprising microalgae, nitrifying bacteria (NB), denitrifying bacteria (DnB), and anaerobic ammonium-oxidation bacteria (AnAOB) in a sequencing batch reactor without mechanical aeration. The experiment was divided into three steps: firstly, cultivating NB; then, adding three kinds of microalgae which were Chlorella sp., Anabaena sp., and Navicula sp. to the bioreactor to construct a microalgae-bacteria symbiotic system; finally, adding anammox sludge to construct the anammox and microalgae-bacteria symbiosis (Anammox-MaBS) system. The results demonstrated that nitrification, denitrification, and anammox processes were coupled successfully, and the maximum TN removal efficiency of the stable Anammox-MaBS system was 99.51 % when the concentration of the influent NH4+-N was 100 mg/L. The addition of microalgae in ammonia wastewater promoted the enrichment of DnB and AnAOB, which were Denitratisoma, Haliangium, unclassified_Rhodocyclaceae, and Candidatus_Brocadia. Furthermore, the unique biofilm structure could effectively alleviate the photoinhibition of light-sensitive bacteria, which may be the reason for the long-term adaptation of Candidatus_Brocadia to light conditions. This research can provide a low-cost solution to bacterial photoinhibition in the coexistence system of microalgae and bacteria without mechanical aeration, offering theoretical support for low-carbon and energy-efficient treatment of wastewater.
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Affiliation(s)
- Jiannv Chen
- School of Environment and Energy, South China University of Technology, Guangzhou, China
| | - Xiangyin Liu
- School of Environment and Energy, South China University of Technology, Guangzhou, China
| | - Tiansheng Lu
- School of Environment and Energy, South China University of Technology, Guangzhou, China
| | - Wenxuan Liu
- School of Environment and Energy, South China University of Technology, Guangzhou, China
| | - Zhiwen Zheng
- School of Environment and Energy, South China University of Technology, Guangzhou, China
| | - Wenxi Chen
- School of Environment and Energy, South China University of Technology, Guangzhou, China
| | - Chu Yang
- School of Environment and Energy, South China University of Technology, Guangzhou, China
| | - Yujie Qin
- School of Environment and Energy, South China University of Technology, Guangzhou, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, PR China.
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9
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Wu X, Kong L, Feng Y, Zheng R, Zhou J, Sun J, Liu S. Communication mediated interaction between bacteria and microalgae advances photogranulation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 914:169975. [PMID: 38218496 DOI: 10.1016/j.scitotenv.2024.169975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/16/2023] [Accepted: 01/04/2024] [Indexed: 01/15/2024]
Abstract
Recently, photogranules composed of bacteria and microalgae for carbon-negative nitrogen removal receive extensive attention worldwide, yet which type of bacteria is helpful for rapid formation of photogranules and whether they depend on signaling communication remain elusive. Varied signaling communication was analyzed using metagenomic method among bacteria and microalgae in via of two types of experimentally verified signaling molecule from bacteria to microalgae, which include indole-3-acetic acid (IAA) and N-acyl homoserine lactones (AHLs) during the operation of photo-bioreactors. Signaling communication is helpful for the adaptability of bacteria to survive with algae. Compared with non-signaling bacteria, signaling bacteria more easily adapt to the varied conditions, evidenced by the increased abundance in the operated reactors. Signaling bacteria are easier to enter the phycosphere, and they dominate the interactions between bacteria and algae rather than non-signaling bacteria. The co-abundance groups (CAGs) with signaling bacteria possess higher abundance than that without signaling bacteria (22.27 % and 6.67 %). Importantly, signaling bacteria accessibly interact with microalgae, which possess higher degree centralities and 32.50 % of them are keystone nodes in the network, in contrast to only 18.66 % of non-signaling bacteria. Thauera carrying both IAA and AHLs synthase genes are highly enriched and positively correlated with nitrogen removal rate. Our work not only highlights the essential roles of signaling communication between microalgae and bacteria in the development of photogranules, but also enriches our understanding of microbial sociobiology.
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Affiliation(s)
- Xiaogang Wu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Lingrui Kong
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Yiming Feng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Ru Zheng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Jianhang Zhou
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Jingqi Sun
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Sitong Liu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, China.
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10
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Zhang JT, Wang JX, Liu Y, Zhang Y, Wang JH, Chi ZY, Kong FT. Microalgal-bacterial biofilms for wastewater treatment: Operations, performances, mechanisms, and uncertainties. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167974. [PMID: 37884155 DOI: 10.1016/j.scitotenv.2023.167974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 09/28/2023] [Accepted: 10/18/2023] [Indexed: 10/28/2023]
Abstract
Microalgal-bacterial biofilms have been increasingly considered of great potential in wastewater treatment due to the advantages of microalgal-bacterial synergistic pollutants removal/recovery, CO2 sequestration, and cost-effective biomass-water separation. However, such advantages may vary widely among different types of microalgal-bacterial biofilms, as the biofilms could be formed on different shapes and structures of attachment substratum, generating "false hope" for certain systems in large-scale wastewater treatment if the operating conditions and pollutants removal properties are evaluated based on the general term "microalgal-bacterial biofilm". This study, therefore, classified microalgal-bacterial biofilms into biofilms formed on 2D substratum, biofilms formed on 3D substratum, and biofilms formed without substratum (i.e. microalgal-bacterial granular sludge, MBGS). Biofilms formed on 2D substratum display higher microalgae fractions and nutrients removal efficiencies, while the adopted long hydraulic retention times were unacceptable for large-scale wastewater treatment. MBGS are featured with much lower microalgae fractions, most efficient pollutants removal, and acceptable retention times for realistic application, yet the feasibility of using natural sunlight should be further explored. 3D substratum systems display wide variations in operating conditions and pollutants removal properties because of diversified substratum shapes and structures. 2D and 3D substratum biofilms share more common in eukaryotic and prokaryotic microbial community structures, while MGBS biofilms are more enriched with microorganisms favoring EPS production, biofilm formation, and denitrification. The specific roles of stratified extracellular polymeric substances (EPS) in nutrients adsorption and condensation still require in-depth exploration. Nutrients removal uncertainties caused by microalgal-bacterial synergy decoupling under insufficient illumination, limited microbial community control, and possible greenhouse gas emission exacerbation arising from microalgal N2O generation were also indicated. This review is helpful for revealing the true potential of applying various microalgal-bacterial biofilms in large-scale wastewater treatment, and will provoke some insights on the challenges to the ideal state of synergistic pollutants reclamation and carbon neutrality via microalgal-bacterial interactions.
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Affiliation(s)
- Jing-Tian Zhang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Jian-Xia Wang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Yang Liu
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Ying Zhang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Jing-Han Wang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China; Key Laboratory of Environment Controlled Aquaculture, Dalian Ocean University, Dalian 116023, PR China.
| | - Zhan-You Chi
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Fan-Tao Kong
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
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Kong L, Feng Y, Du W, Zheng R, Sun J, Rong K, Sun W, Liu S. Cross-Feeding between Filamentous Cyanobacteria and Symbiotic Bacteria Favors Rapid Photogranulation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:16953-16963. [PMID: 37886803 DOI: 10.1021/acs.est.3c04867] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Photogranules are dense algal-bacterial aggregates used in aeration-free and carbon-negative wastewater treatment, wherein filamentous cyanobacteria (FC) are essential components. However, little is known about the functional role of symbiotic bacteria in photogranulation. Herein, we combined cyanobacterial isolation, reactor operation, and multiomics analysis to investigate the cyanobacterial-bacterial interaction during photogranulation. The addition of FC to the inoculated sludge achieved a 1.4-fold higher granule size than the control, and the aggregation capacity of FC-dominant photogranules was closely related to the extracellular polysaccharide (PS) concentration (R = 0.86). Importantly, we found that cross-feeding between FC and symbiotic bacteria for macromolecular PS synthesis is at the heart of photogranulation and substantially enhanced the granular stability. Chloroflexi-affiliated bacteria intertwined with FC throughout the photogranules and promoted PS biosynthesis using the partial nucleotide sugars produced by FC. Proteobacteria-affiliated bacteria were spatially close to FC, and highly expressed genes for vitamin B1 and B12 synthesis, contributing the necessary cofactors to promote FC proliferation. In addition, Bacteroidetes-affiliated bacteria degraded FC-derived carbohydrates and influenced granules development. Our metabolic characterization identified the functional role of symbiotic bacteria of FC during photogranulation and shed light on the critical cyanobacterial-bacterial interactions in photogranules from the viewpoint of cross-feeding.
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Affiliation(s)
- Lingrui Kong
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yiming Feng
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Wenran Du
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ru Zheng
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Jingqi Sun
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Kaiyu Rong
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Weiling Sun
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Sitong Liu
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
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