PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2025
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IF 7.8
Yu Qin,Peng Wan,Heli Tang,Wenxin Shi,Bing Zhang
Aerobic granular sludge membrane bioreactor (AGMBR) is highly efficient in treating urban sewage but is susceptible to membrane fouling caused by extracellular polymeric substances. In this study, we have developed five novel coagulation systems by combining commercially available inorganic coagulants with a self-made modified microbial flocculant (MMF), focusing on evaluating the effects of these systems on normalized fluxes, fouling resistances, wastewater quality characteristics, and membrane surface morphology. The results indicated that the compound coagulation systems had a dual impact on controlling membrane fouling in AGMBRs. Specifically, ferric chloride, polyaluminum chloride, and polyaluminum ferric chloride combined with MMF exacerbated membrane fouling by forming dense cake layers. On the other hand, the composite systems of aluminum sulfate (AS) and MMF, as well as polyferric sulfate and MMF, positively influenced membrane fouling control. Among them, AS neutralized the negative charges of colloidal particles via the positive charges of aluminum ions, thereby destabilizing and aggregating the particles. Meanwhile, the long carbon chains and numerous functional groups in MMF endow it with excellent adsorption bridging capabilities. AS/MMF was found to be the most effective in reducing both reversible and irreversible resistances through electrostatic neutralization and adsorption bridging. The superior performance of the AS/MMF system, characterized by membrane fouling mechanism as standard blocking and an increase in membrane flux associated with reduced turbidity and elevated zeta potential, was further confirmed through extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory analysis. The findings validate the efficacy of AS/MMF composite coagulation pretreatment in mitigating AGMBR membrane fouling, offering a novel solution for sustainable wastewater management.
研究领域:
环境工程
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污水处理
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Bing Zhang,Bo Wang,Heli Tang,Qingjie Li,Wenxin Shi
In this study, an innovative ferric tetrasulfide/peroxymonosulfate (Fe 3 S 4 /PMS) pre-oxidation system was integrated into an aerobic granular membrane bioreactor (AGMBR) to alleviate membrane fouling. The role and underlying mechanisms associated with solution pH was also investigated. The results demonstrated that under optimal conditions (pH 6.0, 0.2 g/L Fe 3 S 4 , and 2.0 mM PMS), pre-oxidation treatment significantly reduced the total membrane fouling resistance by 98 % and shifted the fouling mechanism from cake layer fouling to pore blocking fouling. Moreover, pre-oxidation treatment at pH 6.0 enhanced the energy barrier between foulants-membrane and foulants-foulants, thereby alleviating membrane fouling. The key reactive oxygen species were identified as •OH, SO 4 • – , and 1 O 2 with contributions of 7.03 %, 46.62 %, and 22.38 %, respectively. Furthermore, phosphates significantly inhibited the performance of Fe 3 S 4 /PMS oxidation system for mitigating membrane fouling; however, decreasing solution pH alleviated this inhibition effect. Additionally, an inhibiting effect on coating metal oxide or hydroxide on catalyst surface was observed along with variation in surface charge properties of Fe 3 S 4 when pH was decreased to 6.0, which further promoted activation of PMS for mitigating membrane fouling. This study provides a robust theoretical foundation for employing Fe 3 S 4 /PMS pre-oxidation in AGMBR to alleviate membrane fouling issues which represents an important engineering advancement.
研究领域:
环境工程
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水处理技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2023
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IF 7
Bing Zhang,Kangping Li,Xin Mao,Tengfei Ma,Mingliang Wang,Bing Zhang,Yu Shen,Wenxin Shi
Aerobic granular sludge membrane bioreactors (AGMBRs) are a viable option for municipal sewage reuse; however, the issue of membrane fouling remains a significant obstacle to overcome to achieve large-scale implementation. Therefore, a novel thermal/Fe 2+ /persulfate (PDS) system was proposed to investigate its alleviation effect on membrane fouling in AGMBR. The findings indicated that the thermal/Fe 2+ /PDS system demonstrated superior efficacy in eliminating pollutants from raw sewage. Radical scavenging experiments demonstrated that sulfate radicals and coagulation were the primary contributors to mitigating membrane fouling in the thermal/Fe 2+ /PDS system, effectively reducing fouling resistance and retarding the decline in membrane flux. Analysis of interfacial interaction energy indicated that increasing the electrostatic double-layer repulsion between foulant–membrane and foulant–foulant could mitigate membrane fouling. Additionally, the interfacial characteristics (membrane surface morphology and foulant content) of the fouled membranes were characterized to further validate the efficacy of this system in alleviating membrane fouling. The correlation analysis revealed a positive association between the mitigation of membrane fouling and the substantial elimination of various pollutants, such as chemical oxygen demand , polysaccharides , and suspended solids. This study highlights the exceptional performance of the thermal/Fe 2+ /PDS system and provides novel insights into alleviating AGMBR membrane fouling.
研究领域:
环境工程
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废水处理
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生物技术
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2024
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IF 8.2
Bing Zhang,Xin Mao,Yu Shen,Tengfei Ma,Bing Zhang,Bin Liu,Wenxin Shi
The structural variances of adsorbents play a crucial role in determining the number of effective adsorption sites and pretreatment performance. However, there is still a gap in comprehending the impact of different carbon structural adsorbents on membrane fouling . Therefore, this study aimed to compare the efficacy of granular activated carbon (GAC), powdered activated carbon (PAC), and activated carbon fiber (ACF) in mitigating membrane fouling during municipal sewage reclamation using an aerobic granular sludge membrane bioreactor (AGMBR). The results demonstrated that the utilization of PAC significantly enhanced the normalized flux and reduced fouling resistance in comparison to GAC and ACF systems. PAC effectively adsorbed low and medium-molecular-weight pollutants present in raw sewage, resulting in an increase in average particle size and a decrease in foulant content on the membrane surface. The Hermia model indicated that adsorption pretreatment minimized standard blocking while promoting the formation of a sparse and porous cake layer. Moreover, according to the extended Derjaguin–Landau–Verwey–Overbeek theory, PAC has been demonstrated as the optimal antifouling system owing to its enhanced repulsion between membrane-foulant and foulant-foulant interactions. Correlation analysis revealed that the exceptional antifouling performance of the PAC system was due to its high removal rates of chemical oxygen demand (~78 %) and suspended solids (~97 %). This research offers valuable insights into the mitigation of membrane fouling through the utilization of adsorbents featuring diverse carbon structures .
研究领域:
环境科学
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污水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）