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

Unlocking value from waste: Which circular economy strategies for municipal solid waste management in North Africa? 从废物中释放价值：北非城市固体废物管理的哪种循环经济战略？

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-01-23 DOI: 10.1016/j.cscee.2026.101335

Sarah Ferehoun

The excessive use of resources and inappropriate waste management pose a serious environmental threat, highlighting the need to adopt the circular economy strategies and strengthen the commitment of cities. The main objective of the study is to understand and analyze how waste management practices and strategies implemented by African municipalities promote sustainable benefits and value, while remaining consistent with a circular economy approach. The commitment of municipalities to the circular economy has attracted considerable media and academic interest. However, there is still a lack of empirical studies that shed light on ways to achieve this goal and identify the constraints that lead to failure. To fill this gap, this article draws on a large amount of data collected through interviews, document and report analysis, field visits, and meetings with stakeholders in four Moroccan cities. The study analyzes governance and waste management and valorization practices, examining municipal strategies for the circular economy. It also identifies obstacles to value creation in this area. The research emphasizes that, in order to overcome the various barriers and create value from waste, commitment is needed from citizens, municipalities, and delegated companies. This is based on strategies focusing on culture, policies, resources, management, innovation, and technology. Areas for further research and implications for leaders, policymakers, and other stakeholders are also discussed.

资源的过度使用和不当的废物管理构成了严重的环境威胁，突出表明需要采用循环经济战略和加强城市的承诺。这项研究的主要目的是了解和分析非洲城市实施的废物管理做法和战略如何促进可持续的利益和价值，同时保持与循环经济方法的一致。市政当局对循环经济的承诺吸引了相当多的媒体和学术界的兴趣。然而，仍然缺乏实证研究来阐明实现这一目标的方法，并确定导致失败的制约因素。为了填补这一空白，本文利用了通过访谈、文件和报告分析、实地访问以及与四个摩洛哥城市的利益相关者会面收集的大量数据。该研究分析了治理、废物管理和价值增值实践，考察了循环经济的市政战略。它还指出了这一领域价值创造的障碍。该研究强调，为了克服各种障碍并从废物中创造价值，需要公民、市政当局和委托公司的承诺。这是基于以文化、政策、资源、管理、创新和技术为重点的战略。还讨论了进一步研究的领域以及对领导人、政策制定者和其他利益相关者的影响。

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引用次数: 0

From waste to resource: A system-dynamics analysis of biogas and water reuse synergies in coconut-processing wastewater treatment 从废物到资源：椰子加工废水处理中沼气和水回用协同效应的系统动力学分析

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-02-25 DOI: 10.1016/j.cscee.2026.101349

Feli Zulhendri , Antony Simon , Krishna Pagilla

Industrial expansion and increasing water scarcity in Southeast Asia are pushing agro-industrial facilities to adopt wastewater solutions that recover both energy and water at a reasonable cost. Unlike prior theoretical or static techno-economic studies, this study develops a system-dynamics economic model calibrated with five years of operational data from three full-scale coconut-processing membrane bioreactor (MBR) plants.

The model explicitly couples influent variability, aeration demand, and load-dependent capital and operating expenditure to monthly cost and revenue flows. Four operational configurations were evaluated: baseline treatment, biogas-to-electricity recovery, treated-water reuse, and a combined pathway, together with stress tests that doubled hydraulic and organic loads.

The central contribution is the introduction of deterministic economic threshold maps, which identify the exact load conditions at which decentralized wastewater systems transition from stable operation to financial stress.

Across all plants, the combined recovery configuration delivered the strongest performance, reducing net treatment cost by up to 70% while maintaining stability under fluctuating loads and utility tariffs. By integrating long-term industrial data with dynamic simulation and threshold mapping, this work provides a validated, decision-oriented framework for designing decentralized wastewater systems as resilient, resource-positive infrastructure rather than cost centres.

东南亚的工业扩张和日益严重的水资源短缺促使农用工业设施采用以合理成本回收能源和水的废水解决方案。与先前的理论或静态技术经济研究不同，本研究开发了一个系统动力学经济模型，该模型使用了三个全规模椰子处理膜生物反应器（MBR）工厂5年的运行数据进行校准。该模型明确地将进水变异性、曝气需求和负荷相关的资本和运营支出与每月成本和收入流相结合。评估了四种操作配置：基线处理、沼气发电回收、处理后的水回用和组合路径，以及将水力和有机负荷增加一倍的压力测试。其主要贡献是引入了确定性经济阈值图，确定了分散的废水系统从稳定运行过渡到财务压力的确切负荷条件。在所有工厂中，联合回收配置提供了最强的性能，将净处理成本降低了70%，同时在波动负荷和公用事业费用下保持稳定。通过将长期工业数据与动态模拟和阈值映射相结合，这项工作提供了一个有效的、面向决策的框架，用于将分散的废水系统设计为具有弹性、资源积极的基础设施，而不是成本中心。

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引用次数: 0

Dual-mode Mn– and Sn–Silica composites from millet husk: Photoreduction of Cr(VI) and sulphanilamide, adsorptive capture of basic fuchsin 谷子壳双模Mn -和sn -二氧化硅复合材料：Cr（VI）和磺胺的光还原，碱性紫红的吸附捕获

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-02-12 DOI: 10.1016/j.cscee.2026.101337

G. Sivasubramanian , Nair J. Anagha , P. Devika , P. Archana , Athul Ravi , K.M. Sreedhar , K.M. Sreekanth , Parthasarathi Bera , Anjali Kaiprathu

Biogenic silica extracted from foxtail millet husk has been used as a sustainable matrix for preparing Mn–SiO₂ and Sn–SiO₂ composites with pollutant-specific functionality. Mn incorporation narrows the band gap to ∼3.1 eV and anchors Mn²⁺ within the amorphous network, enabling efficient UV-C-driven photoreduction of Cr(VI) and partial oxidative degradation of sulphanilamide. Sn remains surface-localised, generating Lewis-acidic sites that promote chemisorptive uptake of Basic Fuchsin, achieving 94.5% removal at near-neutral pH. Together, these materials address three pollutant classes, heavy metals, antibiotics and cationic dyes, through orthogonal pathways of redox catalysis (Mn–SiO₂) and adsorption (Sn–SiO₂), without relying on crystalline order or complex synthesis. Structural and spectroscopic analyses (BET, XRD, FTIR, XPS, and DRS) confirm distinct bonding environments and functional divergence between the two dopants. Kinetic modelling shows pseudo-first-order behaviour for Mn-assisted Cr(VI) reduction and pseudo-second-order adsorption for Sn-assisted dye removal. Although competitive-ion effects, reusability and intermediate toxicity were not evaluated, the results establish a proof-of-concept for designing multifunctional, low-cost composites from agricultural waste. This approach highlights the potential for scalable, application-specific remediation using rural biomass as a silica progenitor.

从谷子壳中提取生物源二氧化硅作为可持续基质，制备了具有污染物特异性功能的Mn-SiO2和Sn-SiO2复合材料。Mn的掺入将带隙缩小到~ 3.1 eV，并将Mn2+锚定在无定形网络中，从而实现了uv - c驱动的Cr（VI）的高效光还原和磺胺的部分氧化降解。锡保持表面定位，产生刘易斯酸性位点，促进碱性品红的化学吸附，在接近中性的ph值下达到94.5%的去除率。这些材料通过氧化还原催化（Mn-SiO2）和吸附（Sn - sio2）的正交途径，不依赖于晶体顺序或复杂的合成，可以处理三种污染物：重金属、抗生素和阳离子染料。结构和光谱分析（BET， XRD， FTIR， XPS和DRS）证实了两种掺杂剂之间不同的键合环境和功能差异。动力学模型显示mn辅助Cr（VI）还原的准一级行为和sn辅助染料去除的准二级吸附行为。虽然没有评估竞争效应、可重复使用性和中间毒性，但结果为设计多功能、低成本的农业废弃物复合材料建立了概念验证。这种方法强调了利用农村生物质作为二氧化硅祖物质进行可扩展的、特定应用的修复的潜力。

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引用次数: 0

Integrated mechanical, environmental, and cost assessment of recycled polypropylene–silica fume concrete under moderate thermal exposure 综合机械，环境和成本评估的回收聚丙烯硅粉混凝土在中等热暴露

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-02-21 DOI: 10.1016/j.cscee.2026.101353

Ade Okvianti Irlan , Riska Amalia Anggraini , Stefanny Arentika Panjaitan , Triastuti , Fahmy Hermawan , Amry Dasar , Dahlia Patah

Concrete production contributes substantially to CO₂ emissions and depletion of natural aggregates. This study investigates concrete incorporating recycled polypropylene (PP) granules as a partial fine-aggregate replacement (0–50%) under moderate thermal exposure (25–200 °C). PP-modified mixtures contained 10% silica fume (SF) by mass of cement, while the control mixture contained no SF. Workability and performance were assessed via slump, density, compressive strength, and splitting tensile strength at 28 days, supported by analysis of variance (ANOVA) and scanning electron microscopy (SEM)-based interfacial transition zone (ITZ) observations. At 25 °C, slump decreased from 97 to 87.33 mm and density declined from 2266.88 to 2044.80 kg/m³ (−9.8%) as PP increased to 50%. Compressive and splitting tensile strengths reduced from 32.89 to 20.37 MPa and from 2.83 to 1.89 MPa, respectively. After 200 °C exposure, compressive strength retention was 63.87% for the control and 82.94% for the 25% PP–10% SF mixture. SEM indicated more pronounced interfacial discontinuities at higher PP contents. Screening-level life cycle assessment (LCA), unit-cost indicators, and multi-criteria scoring suggest that 10–25% PP (within the fixed 10% SF system) provides the most balanced trade-off among the PP-modified mixtures.

混凝土生产大大增加了二氧化碳的排放和天然骨料的消耗。本研究研究了在适度热暴露（25-200 °C）下，将再生聚丙烯（PP）颗粒作为部分细骨料替代（0-50%）的混凝土。pp改性混合料含水泥质量硅灰10%，而对照混合料不含硅灰。通过28天的坍落度、密度、抗压强度和劈裂抗拉强度来评估可加工性和性能，并通过方差分析（ANOVA）和基于扫描电子显微镜（SEM）的界面过渡区（ITZ）观察来支持。在25 ℃时，随着PP含量增加至50%，坍落度从97降至87.33 mm，密度从2266.88降至2044.80 kg/m3（- 9.8%）。抗压强度和劈裂抗拉强度分别从32.89降低到20.37 MPa和2.83降低到1.89 MPa。在200 °C暴露后，对照组的抗压强度保持率为63.87%，25% PP-10% SF混合物的抗压强度保持率为82.94%。扫描电镜显示，PP含量越高，界面不连续越明显。筛选级生命周期评估（LCA）、单位成本指标和多标准评分表明，10-25% PP（在固定的10% SF系统内）在PP改性混合物中提供了最平衡的权衡。

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引用次数: 0

Decarbonizing ethylene production via renewable energy electrification: A techno-economic and environmental assessment 通过可再生能源电气化脱碳乙烯生产：技术经济和环境评估

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-01-05 DOI: 10.1016/j.cscee.2026.101323

Rachid Klaimi , Sabla Y. Alnouri , Aleksa Miladinović , Mirko Stijepović

The transition to sustainable production in the chemical industry is essential for achieving global decarbonization targets. This study explores the electrification of an ethylene plant by replacing its conventional natural gas (NG) boilers with electric boilers powered by renewable energy sources. Unlike previous works that focus on single-technology substitution, this paper provides a comprehensive, system-level assessment of ethylene plant electrification by comparing integrated scenarios of concentrated solar power (CSP), photovoltaic (PV) solar energy, and wind power. The optimal configuration is evaluated based on economic feasibility, environmental impact, and land requirements, offering a methodology that can be adopted for other energy-intensive petrochemical processes. The analysis reveals that while wind energy presents the lowest cost among the available renewable sources, its significant land footprint poses a major challenge, particularly when direct power supply to electric boilers is required. Conversely, CSP, despite being the most expensive option, offers the advantage of simultaneously generating steam and power, enhancing system efficiency. PV-based electrification, positioned between wind and CSP in terms of cost and land use, presents a balanced alternative. The study also investigates the prospects of supplementing on-site renewable generation with imported clean electricity to overcome land constraints and improve operational resilience. The findings provide valuable insights into the trade-offs between cost, sustainability, and spatial constraints in electrifying ethylene production, and they outline potential pathways toward a low-carbon, robust and scalable future for the petrochemical sector.

化学工业向可持续生产过渡对于实现全球脱碳目标至关重要。本研究探讨了乙烯工厂的电气化，用可再生能源驱动的电锅炉取代其传统的天然气锅炉。与以往专注于单一技术替代的研究不同，本文通过比较聚光太阳能（CSP）、光伏太阳能（PV）和风能的综合方案，对乙烯装置电气化进行了全面的系统级评估。根据经济可行性、环境影响和土地需求对最佳配置进行评估，提供一种可用于其他能源密集型石化工艺的方法。分析显示，虽然风能是现有可再生能源中成本最低的，但其巨大的土地足迹构成了重大挑战，特别是在需要直接向电锅炉供电时。相反，尽管CSP是最昂贵的选择，但它提供了同时产生蒸汽和电力的优势，提高了系统效率。基于pv的电气化在成本和土地使用方面介于风能和CSP之间，提供了一种平衡的替代方案。该研究还调查了用进口清洁电力补充现场可再生能源发电的前景，以克服土地限制并提高运营弹性。研究结果为乙烯电气化生产的成本、可持续性和空间限制之间的权衡提供了有价值的见解，并概述了石化行业迈向低碳、稳健和可扩展未来的潜在途径。

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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 : 2026-06-01 Epub 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 : 2026-06-01 Epub 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

Performance of Chlorella vulgaris in iron removal from mildly neutralized acid mine drainage 普通小球藻在轻度中和酸性矿井废水中的除铁性能

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2025-12-23 DOI: 10.1016/j.cscee.2025.101316

Lina Patricia Vega Garzon , Paula Moreno , Gloria Lucia Camargo Millán

This research evaluated the performance of Chlorella vulgaris to remove Fe in acid coal mine drainage (AMD) as a resource-efficient treatment strategy. With nutrients and CO₂, the microalgae tolerated up to 100 % of AMD, showing growth rates similar to the control. In iron biosorption, after neutralization at pH 4, efficiencies of 79.8–90.8 % in 1 h and up to 92.4 % in 72 h were achieved. The Sips model best described adsorption (R² = 0.995; 223 mg Fe/g). These results show that minimum neutralization combined with living biomass enhances treatment efficiency and reduces chemical inputs, providing the basis for the scale-up of sustainable phytoremediation systems.

本研究评价了普通小球藻（Chlorella vulgaris）作为一种资源高效处理策略对酸性煤矿废水中铁的去除效果。在营养和二氧化碳的作用下，微藻对AMD的耐受性高达100%，其生长速度与对照组相似。在铁的生物吸附中，在pH 4中和后，1 h的效率为79.8 - 90.8%，72 h的效率高达92.4%。Sips模型最能描述吸附（R2 = 0.995; 223 mg Fe/g）。这些结果表明，最小中和与活生物量的结合提高了处理效率，减少了化学物质的投入，为可持续植物修复系统的规模化提供了基础。

引用次数: 0

Microfluidic-assisted green synthesis of Calotropis procera-derived ZnO quantum dots and evaluation of their antibacterial and antifungal properties against plant pathogens 微流体辅助绿色合成牛角豆衍生氧化锌量子点及其对植物病原体的抗菌和抗真菌性能评价

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-01-19 DOI: 10.1016/j.cscee.2026.101330

Behnam Zanjani Nejad Fard , Fateme Aghamir , Ghasem Eghlima , Tayebeh Moradi Alvand , Zinab Moradi Alvand

This study compared ultrasonic- and microfluidic-assisted green synthesis of zinc oxide quantum dots (ZnO QDs) using Calotropis procera leaf extract as a bio-reducing and stabilizing agent. Both routes generated phase-pure wurtzite ZnO confirmed by XRD; the microfluidic route yielded sharper reflections and narrower size distribution, indicating higher crystallinity and monodispersity. TEM showed aggregated ultrasonic QDs (5–15 nm) versus uniform spherical ones under continuous flow. Optical analyses displayed size-dependent absorption near 398 nm (ultrasonic) and 392 nm (microfluidic) with luminescence peaks at 552–557 nm. EDX verified Zn–O bonding and minimal impurities. Antimicrobial tests revealed stronger activity for QDs than the plant extract, with MIC = 0.10 mg/mL for Ralstonia solanacearum and 0.40–0.80 mg/mL for Pseudomonas syringae. Incorporation into a microfluidic bio-platform enhanced efficacy by improving nanoparticle–cell contact and mixing, resulting in 1.4-fold higher nucleic-acid leakage and 25 % greater K⁺ efflux within 15 min. The QDs also inhibited Botrytis cinerea and Fusarium spp. and showed biosafety (LC₅₀ = 850 ± 21 μg/mL). Overall, the microfluidic method produced structurally uniform, pure, and bio-efficient ZnO QDs, establishing C. procera-derived QDs as sustainable, high-performance antimicrobial nanomaterials.

本研究比较了超声波和微流体辅助氧化锌量子点（ZnO QDs）的绿色合成，并以原花椒叶提取物为生物还原和稳定剂。经XRD证实，两种途径均能生成相纯纤锌矿ZnO；微流控路径反射更清晰，尺寸分布更窄，显示出更高的结晶度和单分散性。透射电镜显示，在连续流动条件下，超声量子点呈聚集状（5 ~ 15 nm），而非均匀球形。光学分析显示在398 nm（超声波）和392 nm（微流体）附近的吸收与尺寸有关，发光峰在552-557 nm。EDX验证了Zn-O键合和最小杂质。抑菌试验结果表明，该QDs的抑菌活性高于植物提取物，其MIC值分别为0.10 mg/mL和0.40 ~ 0.80 mg/mL。将纳米颗粒掺入微流控生物平台中，通过改善纳米颗粒与细胞的接触和混合，提高了功效，15分钟内核酸泄漏量增加了1.4倍，K+流出量增加了25%。QDs对灰霉菌和镰刀菌均有抑制作用，且具有一定的生物安全性（LC50 = 850±21 μg/mL）。总体而言，微流控方法制备了结构均匀、纯净、生物高效的ZnO量子点，建立了C. procera衍生的量子点作为可持续、高性能的抗菌纳米材料。

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引用次数: 0

Effects of feed wastewater characteristics and recovery rate on industrial wastewater reuse by reverse osmosis process 饲料废水特性及回收率对反渗透工艺回用工业废水的影响

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-01-06 DOI: 10.1016/j.cscee.2026.101324

Cong-Sac Tran , Quang-Huy Hoang , Van-Truc Nguyen , Phuong-Thao Nguyen , Mai-Nhu Hoang , Huu-Viet Nguyen , Thi-Kim-Quyen Vo , Xuan-Thanh Bui

The rapid growth of industrial zones has increased wastewater generation and placed pressure on industrial water supplies. This study evaluated the performance, membrane fouling, and energy consumption of a lab-scale RO system at different wastewater sources and recovery rates for potential reuse. The results showed that the quality of effluent after membrane bioreactor (MBR) treatment was higher permeate quality than that after physicochemical 2 (PC2), with overall removals of about 90–96 % for EC, TDS, Ca²⁺, and total hardness, except for total Fe and color. As the recovery increased from 40 to 80 %, removal efficiencies decreased slightly (≤5 %), with the highest overall removal at 60 %. The specific energy consumption (SEC) of the RO system when operating with MBR effluent was 0.96 kWh/m³, about 8 % higher than that after PC2 effluent, and decreased from 0.68 to 0.58 kWh/m³ when the recovery rate increased from 40 % to 80 %. Furthermore, the membrane fouling index when operating with after MBR effluent was 1.1 times lower than that after PC2 effluent and increased with increasing recovery. Therefore, the quality of feed wastewater and recovery rate should be considered when RO systems are applied for wastewater reuse purposes.

工业区的迅速发展增加了废水的产生，给工业用水供应带来了压力。本研究评估了实验室规模的反渗透系统在不同废水来源和潜在再利用回收率下的性能、膜污染和能耗。结果表明，膜生物反应器（MBR）处理后出水的渗透质量优于物理化学2 （PC2）处理后出水，除总铁和总颜色外，EC、TDS、Ca2+和总硬度的去除率约为90 - 96%。当回收率从40%增加到80%时，去除率略有下降（≤5%），最高总去除率为60%。MBR出水运行时，反渗透系统的比能耗（SEC）为0.96 kWh/m3，比PC2出水运行时的比能耗提高约8%；当回收率从40%提高到80%时，反渗透系统的比能耗从0.68 kWh/m3降低到0.58 kWh/m3。MBR处理后的膜污染指数比PC2处理后的低1.1倍，并随着回收率的提高而升高。因此，在将反渗透系统用于废水回用时，应考虑饲料废水的质量和回收率。

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引用次数: 0