Case Studies in Chemical and Environmental Engineering最新文献_第2页

Enhanced nitrogen removal in sponge membrane bioreactor coupled with iron scraps for municipal wastewater treatment: Performance and microbial community shifts 海绵膜生物反应器加铁渣处理城市污水的脱氮效果：性能和微生物群落变化

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-22 DOI: 10.1016/j.cscee.2025.101318

Ngo Hoang Long , Phan Nhu Nguyet , Ngo Thi Thuan , Tran Le Dang Khoa , Xuan-Thanh Bui , Huu-Viet Nguyen , Van-Tung Tra , Masashi Hatamoto , Takahiro Watari , Takashi Yamaguchi

This study investigates the performance of a sponge membrane bioreactor (SMBR) integrated with waste iron scraps as an innovative approach to enhance nitrogen removal from municipal wastewater. The incorporation of iron scraps substantially improved the total nitrogen (TN) removal efficiency, increasing from 35.3 ± 10.4 % to 62.4 ± 26.9 %, while maintaining stable chemical oxygen demand (COD) removal above 90 % and ammonium removal greater than 80 % at an iron dosage of 60 g/L. Iron supplementation promoted denitrification by creating localized anoxic microenvironments and stimulating the enrichment of iron-reducing and denitrifying bacteria such as Geothrix, Aquabacterium, and Roseiarcus, with relative abundances increasing from 0.2 % to 6.1 %, 1.4 %–4.8 %, and 0.8 %–1.5 %, respectively. Microbial community analysis further revealed significant shifts in dominant phyla, including Proteobacteria, Acidobacteriota, and Bacteroidota, with relative abundances increased from 68.3 % to 70.1 %, 2.0 %–9.1 %, and 1.0 %–7.8 %, respectively. These shifts indicate strengthened nitrogen transformation pathways within the system. These findings demonstrate that the reuse of waste iron scraps as bioactive carriers is an effective and environmentally sustainable strategy for enhancing nitrogen removal efficiency and microbial functional diversity in SMBR.

本研究研究了海绵膜生物反应器（SMBR）与废铁渣的结合，作为一种创新的方法来提高城市污水中氮的去除效果。铁屑的加入显著提高了总氮（TN）的去除率，从35.3±10.4%提高到62.4±26.9%，同时在铁投加量为60 g/L时，化学需氧量（COD）去除率稳定在90%以上，铵态氮去除率稳定在80%以上。补铁通过建立局部缺氧微环境和刺激土思菌、水藻菌和玫瑰菌等铁还原菌和反硝化菌的富集，促进了反硝化作用，相对丰度分别从0.2%增加到6.1%、1.4% - 4.8%和0.8% - 1.5%。微生物群落分析显示，优势门Proteobacteria、acidobacteria和Bacteroidota的相对丰度分别从68.3%增加到70.1%、2.0% - 9.1%和1.0% - 7.8%。这些变化表明系统内氮转化途径加强。上述研究结果表明，废铁渣作为生物活性载体的再利用是提高SMBR脱氮效率和微生物功能多样性的有效且环境可持续的策略。

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引用次数: 0

Environmental degradation of plastics containing pro-oxidant additives and their toxicological impact in desert ecosystems 含促氧化添加剂塑料的环境降解及其对沙漠生态系统的毒理学影响

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-19 DOI: 10.1016/j.cscee.2025.101311

Diya Alsafadi, Mohammad Abu Nuwar, Amani Abdelhadi, Tasnim Alqaruoti, Lama Siwwan, Ahmad Al Amaireh

The accumulation of single-use plastic materials poses significant environmental and waste management challenges. Pro-oxidant additive-containing (PAC) plastics have been introduced in many regions to mitigate these impacts. This study examined the abiotic degradation of PAC plastics under accelerated laboratory conditions and in an open-air environment with a hot, dry climate. Residual materials from abiotic degradation were then subjected to aerobic biodegradation in soil, and the final products were evaluated for plant toxicity. Fourier-transform infrared spectroscopy (FT-IR) analysis revealed the formation of acids, ketones, and aldehydes on the polymer surface due to oxidation under accelerated conditions. In open-air exposure, the reduction in weight average molecular weight (Mw) was used to assess degradation. A rapid Mw decrease occurred within the first three months, and after fifteen months, 50 % of the samples showed low Mw (<5.0 kDa). The abiotic residues were subsequently mineralized in soil, achieving 15–20 % biodegradation after 350 days. Samples not pre-exposed to open-air conditions showed only 5 % mineralization, confirming that prior thermal and photo-oxidation enhanced biodegradability. Eco-toxicity tests indicated that the biodegradation products did not affect the growth of the studied plant species.

一次性塑料材料的积累对环境和废物管理构成重大挑战。含有促氧化添加剂（PAC）的塑料已在许多地区引入以减轻这些影响。本研究考察了加速实验室条件下PAC塑料的非生物降解和炎热干燥气候下的露天环境。然后，非生物降解的残余物质在土壤中进行好氧生物降解，并评估最终产物的植物毒性。傅里叶变换红外光谱（FT-IR）分析显示，在加速氧化条件下，聚合物表面形成酸、酮和醛。在露天暴露中，用重量平均分子量（Mw）的减少来评估降解。在前三个月内，Mw迅速下降，15个月后，50%的样品显示低Mw （<5.0 kDa）。非生物残留物随后在土壤中矿化，350天后达到15 - 20%的生物降解。未预先暴露在露天条件下的样品显示只有5%的矿化，证实了事先的热氧化和光氧化增强了生物降解性。生态毒性试验表明，生物降解产物不影响所研究植物的生长。

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引用次数: 0

Long-term full-scale evaluation of three membrane bioreactor plants for coconut-processing wastewater treatment: Energy, cost, and pretreatment impacts 三个膜生物反应器厂对椰子加工废水处理的长期全面评估：能源、成本和预处理影响

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-17 DOI: 10.1016/j.cscee.2025.101310

Feli Zulhendri , David Stuckler , Antony Simon , Felix Zulhendri , Krishna Pagilla

Data from three full-scale membrane bioreactor (MBR) plants treating coconut-processing wastewater in North Sumatra, Indonesia, were collected over five years and analyzed using a mass-balance, load-based framework. Energy and cost were reported as intensities (kWh/kg and USD/kg COD removed) and as volumetric indicators (kWh/m³ and USD/m³ of wastewater treated). All plants achieved >99.5 % removal of COD, BOD, and TSS. The electricity demand ranged from 0.37 to 0.82 kWh/m³, and the treatment cost ranged from 37.7 to 69.5 USD/m³ among the three plants. On a load basis, COD removal required 0.015 to 0.182 kWh/kg and 3.19 to 11.7 USD/kg; BOD removal required 0.148 to 0.518 kWh/kg and 9.95 to 33.5 USD/kg; and TSS removal required 0.339 to 1.99 kWh/kg and 27.7 to 43.9 USD/kg. Plants with better pretreatment, including filter presses and fermentation tanks, consistently achieved lower energy use and cost. Regression analysis confirmed that each additional kilogram per day of residual TSS in wastewater increased downstream aeration and MBR electricity demand by 0.41 kWh/day (p < 0.001). This study provides the first multi-year, full-scale benchmarks for MBR treatment of high-strength coconut wastewater and demonstrates how practical solids-oil pretreatment can halve energy demand and double cost-effectiveness. The findings offer actionable guidance for engineers, operators, and regulators designing sustainable agro-industrial wastewater systems.

来自印度尼西亚北苏门答腊岛三个处理椰子加工废水的全规模膜生物反应器（MBR）厂的数据收集了五年多的时间，并使用质量平衡、基于负载的框架进行了分析。能源和成本以强度（kWh/kg和USD/kg去除COD）和体积指标（kWh/m3和USD/m3处理的废水）报告。所有工厂的COD、BOD和TSS去除率均达到99.5%。三个电厂的用电量在0.37 ~ 0.82 kWh/m3之间，处理成本在37.7 ~ 69.5 USD/m3之间。按负荷计算，COD去除率为0.015 ~ 0.182 kWh/kg, 3.19 ~ 11.7 USD/kg；BOD去除率为0.148 ~ 0.518 kWh/kg, 9.95 ~ 33.5 USD/kg；TSS去除率为0.339 ~ 1.99 kWh/kg, 27.7 ~ 43.9 USD/kg。具有较好预处理的工厂，包括压滤机和发酵罐，始终实现较低的能源使用和成本。回归分析证实，废水中残留TSS每天每增加一公斤，下游曝气和MBR电力需求就会增加0.41千瓦时/天（p < 0.001）。这项研究为MBR处理高强度椰子废水提供了第一个多年的全面基准，并展示了实用的固体油预处理如何将能源需求减半，成本效益翻倍。研究结果为设计可持续农业工业废水系统的工程师、运营商和监管机构提供了可操作的指导。

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引用次数: 0

Organizational life cycle assessment: A case study in the fashion industry small and medium enterprises 组织生命周期评估：时尚行业中小企业的案例研究

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-17 DOI: 10.1016/j.cscee.2025.101313

Salik Ahmed , Marco Ciro Liscio , Paolo Sospiro , Irene Voukkali , Antonis A. Zorpas

Organizations are increasingly committed to reducing their environmental footprints, a process fraught with the complex challenge of identifying and mitigating unique environmental impacts and hotspots without merely shifting burdens elsewhere. This study applies Organizational Life Cycle Assessment (OLCA) methodology using ISO 14040/14044 and ISO/TS 14072 guidance, mapped gate-to-gate flows for the firm's entire 2023 output. Inputs and emissions were compiled on-site and modelled in SimaPro 9.1.1 with the Ecoinvent 3.3 “allocation, cut-off” database, applying ReCiPe 2016 Midpoint (H) across 18 impact categories. The results show that electricity use is the main environmental hotspot, contributing 43.5 % to total climate impacts, while cotton fibre accounts for 87.3 % of freshwater eutrophication and 37.8 % of water consumption; combined measures on renewable electricity and recycled fibres could reduce the organisation's overall climate footprint by up to 34.6 %. To address these impacts, the adoption of renewable energy sources like solar energy systems to reduce electricity consumption is recommended. This analysis pinpoints concise improvements: transition to renewable electricity, favour green suppliers of water-efficient cotton and recycled polyester and replace brass with different materials. The analysis conducted aims to be transferable to peer fashion companies in Italy and beyond, favouring the spread of Life Cycle based methodologies.

组织越来越致力于减少其环境足迹，这一过程充满了复杂的挑战，即识别和减轻独特的环境影响和热点，而不仅仅是将负担转移到其他地方。本研究采用组织生命周期评估（OLCA）方法，采用ISO 14040/14044和ISO/TS 14072指南，为公司整个2023年的产出绘制了门到门的流程。输入值和排放量在现场进行编译，并在SimaPro 9.1.1中使用Ecoinvent 3.3“分配，截止”数据库进行建模，并在18个影响类别中应用ReCiPe 2016 Midpoint (H)。结果表明，电力使用是主要的环境热点，占总气候影响的43.5%，而棉纤维占淡水富营养化的87.3%，占用水量的37.8%；可再生电力和回收纤维的综合措施可以将该组织的总体气候足迹减少34.6%。为了解决这些影响，建议采用可再生能源，如太阳能系统，以减少电力消耗。这一分析指出了一些简明的改进措施：向可再生电力过渡，支持节水棉和再生聚酯的绿色供应商，用不同的材料代替黄铜。所进行的分析旨在转移到意大利及其他地区的同行时尚公司，有利于基于生命周期的方法的传播。

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引用次数: 0

Data-driven investigation of the solvent effect in Diels-Alder reaction Diels-Alder反应溶剂效应的数据驱动研究

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-17 DOI: 10.1016/j.cscee.2025.101314

Benny Wahyudianto , Takashi Saito , Haruki Nagae , Yoshihiro Takebayashi , Sho Kataoka

The Diels-Alder (DA) reaction on 25 solvents was evaluated using in situ UV–Visible spectrophotometer. The solvent effect was investigated by using machine learning based on experimental data to identify key factors in the reaction. The data analysis unveiled Catalán acidity, basicity, and dipolarity as three important solvent parameters. These parameters accounted for the exceptional behavior of fluorinated solvents, such as 1,1,1,3,3,3-hexafluoroisopropanol, which exhibited a significantly higher rate constant (k₂ = 3.821 M⁻¹ s⁻¹) compared to other organic solvents. Furthermore, we also compare our results with preliminary density functional theory calculations to better understand the solvent effect, especially fluorinated solvent.

采用原位紫外可见分光光度计对25种溶剂上的Diels-Alder （DA）反应进行了评价。在实验数据的基础上，利用机器学习方法研究溶剂效应，识别反应中的关键因素。数据分析表明Catalán酸度、碱度和双极性是溶剂的三个重要参数。这些参数解释了氟化溶剂的异常行为，例如1,1,1,3,3,3-六氟异丙醇，与其他有机溶剂相比，其速率常数（k2 = 3.821 M−1 s−1）显着更高。此外，我们还将我们的结果与密度泛函理论的初步计算结果进行了比较，以更好地理解溶剂效应，特别是氟化溶剂效应。

引用次数: 0

Hydrogen peroxide-based oxidation and pH-controlled precipitation for the recovery of non-cerium rare earth elements from permanent magnet waste 以过氧化氢为基础的氧化- ph控制沉淀法从永磁体废料中回收非铈稀土元素

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-13 DOI: 10.1016/j.cscee.2025.101307

Jose Luis Aldana, Jokin Hidalgo, Carmen del Rio, Javier Antoñanzas

This case study presents a sustainable and scalable process for the recovery of non-cerium rare earth elements (non-Ce REE) from end-of-life neodymium–iron–boron (NdFeB) permanent magnets. The method involves the selective precipitation of cerium using hydrogen peroxide at pH 5.5 and a NaOH/REE weight ratio between 0.41 and 0.45. Under these conditions, cerium was effectively removed from the leachate with a precipitation yield exceeding 99 wt%. The resulting cerium-based precipitate was calcined at 900 °C, and subsequent leaching in 1 M HCl enabled the recovery of non-Ce REE, including neodymium, praseodymium, gadolinium and dysprosium, with a maximum recovery rate of 97.9 wt%. The cerium content in the final product was controlled between 0.07 wt% and 2.1 wt% by adjusting the precipitation temperature, allowing for the production of two distinct rare earth oxide streams. The process was validated using real leachates obtained from the recycling of industrial magnet waste, demonstrating its applicability in real-world scenarios. The use of environmentally benign reagents and well-established unit operations supports the industrial feasibility and environmental sustainability of the proposed method. The results highlight the potential of this approach for the recovery of critical raw materials in line with circular economy and decarbonisation goals, offering a viable solution for the sustainable management of rare earth resources in industrial recycling contexts.

本案例研究提出了一种从报废的钕铁硼永磁体中回收非铈稀土元素（non-Ce REE）的可持续和可扩展的工艺。该方法使用过氧化氢在pH 5.5， NaOH/REE重量比在0.41 ~ 0.45之间选择性沉淀铈。在此条件下，铈能有效地从渗滤液中去除，沉淀率超过99%。得到的铈基沉淀物在900℃下煅烧，随后在1 M HCl中浸出，可以回收非ce REE，包括钕、镨、钆和镝，最大回收率为97.9%。通过调节沉淀温度，最终产品中的铈含量控制在0.07 wt% ~ 2.1 wt%之间，从而产生两种不同的稀土氧化物流。利用回收工业磁铁废弃物获得的真实渗滤液对该工艺进行了验证，证明了其在现实场景中的适用性。使用环境友好的试剂和完善的单元操作支持工业可行性和环境可持续性提出的方法。研究结果突出了这种方法在回收关键原材料方面的潜力，符合循环经济和脱碳目标，为工业回收环境下稀土资源的可持续管理提供了可行的解决方案。

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引用次数: 0

Continuous gasification-pyrolysis of fresh palm fruit bunches for biochar production and carbon sequestration 新鲜棕榈果束的连续气化热解生产生物炭和固碳

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-09 DOI: 10.1016/j.cscee.2025.101309

Nathawat Unsomsri , Pachara Koedthong , Sittinun Tawkaew , Songkran Wiriyasart , Sommas Kaewluan

The growing need for sustainable alternatives to fossil-derived heating motivates the development of biomass-based thermal systems for waste valorization. This study designed and operated a continuous pyrolysis system integrated with an updraft gasifier-syngas burner, using wood pellets as a renewable heat source to convert fresh palm fruit bunches (FFB) into valuable bio-products. The system replaced LPG heating, enabled direct utilization of undried FFB, and enhanced operational scalability. Stable operation was achieved at 1078 °C with low CO (280 mg Nm⁻³) and particulate emissions (56 mg Nm⁻³). Pyrolysis at 500 °C yielded biochar (9.5 wt%, HHV 28.1 MJ kg⁻¹, with 23 % carbon retention equivalent to 44.7 tCO₂eq yr⁻¹), pyrolysis oil (21.9 wt%), wood vinegar (40.0 wt%), and gases (28.6 wt%). Techno-economic analysis indicated a net profit of 4.08 EUR h⁻¹ and a short payback period of 1.5–1.9 years. These findings demonstrate that the integrated biomass gasification-pyrolysis system offers a technically feasible and economically attractive solution for low-carbon conversion of palm residues into energy and carbon-rich materials.

日益增长的需求可持续替代化石来源的加热激励了基于生物质的热系统的发展，用于废物增值。本研究设计并运行了一个集成了上升气流气化炉-合成气燃烧器的连续热解系统，利用木屑颗粒作为可再生热源，将新鲜棕榈果束（FFB）转化为有价值的生物产品。该系统取代了LPG加热，可以直接利用未干燥的FFB，并提高了操作的可扩展性。在1078°C下稳定运行，低CO （280 mg Nm - 3）和颗粒排放（56 mg Nm - 3）。500°C热解产生生物炭（9.5 wt%, HHV 28.1 MJ kg - 1, 23%的碳保留率相当于44.7 tCO2eq yr - 1）、热解油（21.9 wt%）、木醋（40.0 wt%）和气体（28.6 wt%）。技术经济分析表明，净利润为4.08欧元/小时，投资回收期较短，为1.5-1.9年。这些发现表明，生物质气化-热解一体化系统为棕榈渣低碳转化为能源和富含碳的材料提供了技术上可行和经济上有吸引力的解决方案。

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引用次数: 0

Synthesis of industrial waste-based geopolymer catalyst and its application in removing imidacloprid insecticide from water 工业废渣基地聚合物催化剂的合成及其在水中吡虫啉脱除中的应用

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-07 DOI: 10.1016/j.cscee.2025.101308

Samunya Sanguanpak , Premmanus Chittachumnonk , Chart Chiemchaisri , Ming Chun Lu

Geopolymer granules containing fly ash as aluminosilicate materials and mill scale as a catalyst were applied for photocatalytic degradation of imidacloprid insecticide. The surface properties of the geopolymer catalyst were optimized by providing an optimum ratio of waste materials and pore-forming agents. The geopolymer catalyst yielded complete imidacloprid removals during batch experiments, with more than 80 % of its removals taking place after only 1 h of UV exposure. High photocatalytic activities were maintained over 10 repetitive cycles, exhibiting its longevity during which a gradual release of sediment with higher photocatalytic activities was observed, thus increasing its overall photocatalytic degradation rate of the geopolymer catalyst.

以粉煤灰为硅酸铝材料，磨渣为催化剂的地聚合物颗粒进行了吡虫啉杀虫剂光催化降解研究。通过提供最佳配比的废料和成孔剂，优化了地聚合物催化剂的表面性能。在批量实验中，地聚合物催化剂产生了完全去除吡虫啉的效果，在紫外线照射1小时后，80%以上的吡虫啉被去除。在10个重复循环中保持较高的光催化活性，表现出较长的寿命，在此期间观察到具有较高光催化活性的沉积物逐渐释放，从而提高了其对地聚合物催化剂的总体光催化降解率。

引用次数: 0

Synthesis of Fe-, Co-doped TiO2/vermiculite for enhanced antibiotic adsorption and photocatalytic degradation 铁、共掺杂TiO2/蛭石的合成及其增强抗生素吸附和光催化降解

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-04 DOI: 10.1016/j.cscee.2025.101305

Vu Van Tu , Nguyen Thi Hue , Hoang Minh Thang , Nguyen Duc Van , Tran Van An , Dinh-Trinh Tran , Nguyen Thi Thanh Hai

Herein, Fe-, Co-doped TiO₂ semiconductors dispersed on acid-modified vermiculite were successfully synthesized using sol-gel method. The photocatalytic activity and adsorption capacity of Fe-, Co-doped TiO₂ catalysts were evaluated through the removal of ciprofloxacin antibiotic in water. Fe-, Co-doped TiO₂/Vermiculite (Ver) were mesoporous materials with specific surface areas of 162.7 m²/g (Fe-doped TiO₂), and 172.7 m²/g (Co-doped TiO₂/Ver). The combination between Fe-, Co-doped TiO₂ and Ver resulted in an improved visible light absorption, with band gap energy decreasing from 3.31 eV (TiO₂), to 2.02 eV (Fe-doped TiO₂), and 1.79 eV (Co-doped TiO₂), enhancing the photocatalytic performance and absorption capacity. The Fe-, Co-doped TiO₂/Ver achieved 96.1 % of ciprofloxacin (50 mg/L) removal by photocatalytic process. Anions inhibited photocatalytic activity with the following order Cl⁻ > H₂PO₄⁻ > I⁻, while HO^• and h⁺ were primary reactive species generated. Adsorption process followed the Freundlich isotherm (R² > 0.99) and pseudo-second-order kinetics (R² > 0.98), suggesting the involvement of physico-chemical adsorption processes. The photodegradation process adhered to pseudo-first-order kinetics, with a maximum rate constant of 0.43 min⁻¹. Co-, Fe-doped TiO₂/Ver maintained good ciprofloxacin removal efficiencies after three reused cycles, demonstrating its high stability. This study presents a promising approach for removing antibiotic residues from water.

本文采用溶胶-凝胶法制备了分散在酸修饰蛭石上的Fe- co掺杂TiO2半导体。通过对水中环丙沙星抗生素的去除，评价了Fe-、共掺杂TiO2催化剂的光催化活性和吸附能力。Fe-、co掺杂TiO2/Vermiculite （Ver）为介孔材料，比表面积分别为162.7 m2/g （Fe掺杂TiO2）和172.7 m2/g （co掺杂TiO2/Ver）。Fe-、共掺杂TiO2和Ver的结合改善了可见光吸收，带隙能量从3.31 eV （TiO2）降低到2.02 eV （Fe-掺杂TiO2）和1.79 eV (co -掺杂TiO2)，增强了光催化性能和吸收能力。Fe- co掺杂TiO2/Ver光催化对环丙沙星（50 mg/L）的去除率达到96.1%。阴离子抑制光催化活性的顺序为Cl−>； H2PO4−> I−，而HO•和h+是主要的活性物质。吸附过程遵循Freundlich等温线（R2 > 0.99）和拟二级动力学（R2 > 0.98），表明参与了物理化学吸附过程。光降解过程符合准一级动力学，最大速率常数为0.43 min−1。Co-， fe掺杂的TiO2/Ver经过三次重复使用后仍保持良好的环丙沙星去除率，表现出较高的稳定性。本研究提出了一种有前途的去除水中抗生素残留的方法。

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引用次数: 0

Reverse osmosis treatment of blow-down water for beneficial reuse and sustainable power generation 对排污水进行反渗透处理，有利于回用和可持续发电

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2025-12-03 DOI: 10.1016/j.cscee.2025.101306

Claudio Kohn , Hung Cong Duong , Viet Quang Ly , Long Duc Nghiem

Reverse osmosis (RO) has been widely adopted for the treatment of blow-down water to facilitate sustainable water management in thermal power plants. This study investigates membrane fouling in a packaged RO system treating blow-down water to identify the causes of permeate flux decline and develop mitigation strategies. Results from blow-down water analysis, autopsy of the used membrane, and filtration experiments indicate that the RO system was likely under-designed with water recovery exceeding the design limit, creating conditions favourable for flux deterioration. Silica, present in blow-down water at high concentrations (∼50 mg/L), was identified as the dominant and most challenging membrane fouling culprit. Given the sulphate concentrations of 55–88 mg/L, barium sulphate scaling might also occur; however, the evidence was inconclusive. Unlike silica scaling, barium sulphate could be mitigated through appropriate anti-scalant dosing. The filtration experiments indicate that besides fouling, membrane compaction partially contributed to flux decline. Finally, WAVE simulation results suggest key strategies (e.g. lower water recovery, using larger membrane surface area or membrane with improved flux stability, increasing feed water temperature (up to 35 °C), blending with silica-free water sources, and optimising anti-scalant dosing) to enhance RO system water recovery while effectively avert membrane fouling.

反渗透（RO）技术已被广泛应用于火电厂排污水的处理，以促进火电厂水的可持续管理。本研究调查了袋装反渗透系统处理排污水中的膜污染，以确定渗透通量下降的原因并制定缓解策略。排污水分析、废膜解剖和过滤实验的结果表明，反渗透系统可能设计不足，水回收率超过了设计极限，为通量恶化创造了有利条件。二氧化硅，以高浓度（~ 50 mg/L）存在于排污水中，被确定为主要和最具挑战性的膜污染罪魁祸首。当硫酸盐浓度为55 ~ 88 mg/L时，也可能发生硫酸钡结垢；然而，证据是不确定的。不像二氧化硅结垢，硫酸钡可以通过适当的抗结垢剂剂量减轻。过滤实验表明，除污染外，膜压实也是导致通量下降的部分原因。最后，WAVE模拟结果提出了提高反渗透系统水回收率的关键策略（例如，降低水回收率，使用更大的膜表面积或提高通量稳定性的膜，提高给水温度（高达35°C），与无硅水源混合，以及优化抗垢剂剂量），同时有效避免膜污染。

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引用次数: 0