WATER SCIENCE AND TECHNOLOGY
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2024
·Vol. 89
·期 4
·873-886
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IF 2.5
Tao Haiyan,Cao Xiaochang,Song Rujie,Zhou Zebin,Cheng Fang
A membrane-aerated biofilm reactor (MABR) combines membrane technology with biofilm processes and has unique advantages in the treatment of organic wastewater and volatile wastewater. The common membranes for MABR systems usually have relatively uneven pore structures and low bubble point pressure, resulting in unsatisfactory O 2 utilization and wastewater treatment efficiency. In this work, polydimethylsiloxane (PDMS) and UiO-66 (a Zr-based metal organic framework) were coated on the surface of a commercial polypropylene (PP) hollow fiber membrane to prepare oxygen-rich MABR membranes and modules, which showed an attractive O 2 utilization rate and wastewater treatment efficiency. The bubble points of the PDMS and PDMS-UiO-66 membranes were significantly higher than those of the PP membranes, and the PDMS-UiO-66 membranes had better oxygen enrichment capacity and biological affinity. The optimal PDMS-UiO-66 membrane modules had an O 2 permeance of 31.65 GPU (1 GPU = 3.35 × 10 −10 mol m −2 s −1 Pa −1 ), with O 2 /N 2 selectivity of 2.21. The membrane hanging effect and processing capacity for domestic sewage were greatly improved. This study may provide insights and guidelines to fabricate porous mixed matrix membranes and modules in the industry for MABR. The developed products are expected to be applied in the actual separation process. PDMS and PDMS-UiO-66 were coated on the PP support to prepare O 2 -rich MABR membranes and modules. With UiO-66 loading, the module has a higher O 2 /N 2 separation performance, a rougher and more hydrophilic membrane surface. The PDMS-UiO-66 membrane module exhibits a good biofilm hanging effect and high NH 4 + -N removal performance.
研究领域:
环境科学
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材料科学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jianguo Li,Wanli Yan,Shikan Zheng,Chengsong Ye,Yangying Zhao,Xin Yu
Membrane types are known to have a decisive effect on the operational efficiency of membrane-bound reactors. The gas-permeable membrane, serving as the biofilm growth and oxygen transfer medium, plays a vital role in the membrane-aerated biofilm reactor (MABR). However, few studies have thoroughly investigated how membrane types affect MABR performance. Four parallel MABRs were equipped with different membrane types: microporous PTFE (R1), dense silicone (R2), composite A (R3), and composite B (R4) membranes. Results showed that the R3 and R4 exhibited comparable and superior COD and nitrogen removal efficiency relative to R1, maintaining stable transmembrane pressure. XDLVO theory was used to assess the interfacial interaction energy between sludge flocs and membrane surfaces. Polar forces were crucial for sludge adhesion, affecting biofilm formation and growth. Composite B exhibited the lowest energy barrier (2529 KT), leading to the fastest biofilm formation and thicker biofilms, which enhance nitrogen removal. PTFE exhibited the highest energy barrier (9655 KT), resulting in the most extended biofilm cultivation period and the thinnest biofilm. Based on fluorescent in-situ hybridization (FISH), membrane types significantly affect the distribution of nitrogen-removing microbial communities. As the biofilm thickened, the stratification of the nitrifying bacterial population became increasingly pronounced, forming distinct layers within the biofilm. Nitrosomonas and Nitrobacter dominated the biofilm near the membrane, while Nitrospira was most abundant in the outer biofilm. The outermost biofilm layer was predominantly composed of heterotrophic denitrifying bacteria (HDB). The research has shown that different biofilm types exhibit heterogeneity stratification in nitrifying bacteria and HDB. 16S rRNA genes sequencing revealed that Nitrospira was the predominant nitrifying genus within the heterotrophic/autotrophic biofilm.
研究领域:
环境工程
·
微生物学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2013
·
IF 4.75
Feifei Hou,Baoan Li,Minghao Xing,Qin Wang,Liang Hu,Shichang Wang
A novel composite hollow fiber membrane for membrane aerated biofilm rector (MABR) was prepared by coating L-3,4-dihydroxyphenylalanine (DOPA) on the surface of PVDF membrane. MABR process study was conducted to test the performances of the original and modified membranes for 166 days. The results indicate that coated membrane showed 2 times higher gas flux, lower water contact angle (declined from 86.5° to 52°), and significantly improved surface roughness. The modified membrane displayed an excellent MABR performance. Its COD, NH 4 + –N and TN removal efficiencies were kept above 90%, 98.8% and 84.2% during the first 4-month experiment. By tracking experiment at 0.01 MPa, to achieve COD removal efficiency of 85.9%, half an hour is required with the modified membrane, instead of 6 h using the original one. Besides, faster NH 4 + –N and TN removal at 0.01 MPa were also achieved with DOPA composite membrane.
研究领域:
环境工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2025
·
IF 8.4
Shumin Qin,Lin Deng,Yan Lin,Lang Jiang,Xilong Liu,Qian Zhang
To enhance the stability of membrane aerated biofilm reactor (MABR) and accelerate the formation of biofilm, this study introduced a symbiotic system composed of heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria and Chlorella into the MABR, and compared it with a control system inoculated with HN-AD bacteria and activated sludge. The effects of adding 0.8 μM exogenous C8-HSL on biofilm formation and the efficiency of nitrogen and phosphorus removal were investigated by comparing systems with and without the signaling molecule. Results showed that 0.8 μM C8-HSL enhanced the removal efficiencies of ammonia nitrogen, total nitrogen (TN), and total phosphorus (TP) by 25.17 %, 36.22 %, and 38.74 %, respectively, and increased extracellular polymeric substances (EPS) production by 68.62 %. High-throughput sequencing identified Desulfomicrobium and Aliidiomarina as the dominant microorganisms involved in nitrogen and phosphorus removal. The nirB gene played a key role in the denitrification process, and phoBR gene was essential for phosphorus removal. This study provides theoretical support for the application of quorum sensing in MABR systems, offering a novel strategy to improve the efficiency and stability of high ammonia wastewater treatment.
研究领域:
环境工程
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微生物学
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生物技术
·
废水处理
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL ENGINEERING
·
2022
·
IF 1.352
Guolong Li,Mengyao Li,Yulin Zuo,Xinlei Suo,Hang Su,Yunzheng Wang,Longsheng Hu,Weidi Shi,Liwen Hu
Serious nonradiative recombination and decomposition of perovskite film exist in MAPbBr3-based perovskite light-emitting diodes (PeLED) due to the residue of lead atoms from an incomplete reaction, thereby limiting the efficiency of PeLEDs. Excessive Methylammonium bromide (MABr) added into the precursor of methylammonium lead bromide (MAPbBr3) can solve this problem. However, how the excessive MABr self-passivates perovskite films improves the performance of PeLEDs requires further examination. The self-passivated perovskite film by overdoping MABr was investigated by varying stoichiometric ratios of perovskite precursors. It was found that, as the content of MABr increased, the interaction between free charge and longitudinal optical phonons was enhanced, thus reducing the exciton binding energy, resulting in emission broadening and blue shift of the PL spectra. With the molar ratio of PbBr2 and MABr of 1:1.315, the PeLED achieved a good trade-off between the brightness and the stability, thus demonstrating a maximum brightness of 9981 cd m − 2 and a lifetime of 14 min, with a maximum current efficiency of 6.59 cd A − 1.
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Xiang Mei,Yihan Wang,Yang Yang,Lijie Xu,Yong Wang,Zhongwei Guo,Wentian Shen,Zimiao Zhang,Mengyuan Ma,Yang Ding,Yanyan Xiao,Xu Yang,Chengqi Yin,Wei Guo,Kang Xu,Chaofan Wang
Nitroaniline (NA) is an aniline derivative with high toxicity, potential carcinogenicity and mutagenic effects. At present, the physical, chemical and biological methods used in NA-containing wastewater treatment usually suffer from problems such as low removal efficiency, high energy consumption and secondary pollution generation. In this study, a membrane-aerated biofilm reactor (MABR) was constructed to enhance the treatment of wastewater containing o -nitroaniline (2-NA) and p -nitroaniline (4-NA). The stratified biofilm and counterdiffusion of oxygen in the MABR were conducive to NA degradation. At a lower concentration, NA was primarily removed through direct oxidative degradation in the absence of the cometabolic substrate acetic acid, while at a higher concentration, NA was predominantly removed through oxidative degradation after reduction of NA in the presence of acetic acid. With an influent NA loading of 0.120 kg/(m 3 ·d), an aeration pressure of 40 kPa and an acetic acid dosing ratio of 2.0, the 2-NA and 4-NA removal loadings reached 0.058 and 0.060 kg/(m 3 ·d), respectively. Additionally, the chemical oxygen demand (COD) and total nitrogen (TN) removal rates were 82.40 and 88.52%, respectively. The MABR technology promoted simultaneous NA degradation and nitrogen removal from NA-containing wastewater treatment, illustrating its prospects for industrial application.
研究领域:
环境工程
·
水处理
·
生物技术
·
废水管理
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）