Case Studies in Chemical and Environmental Engineering最新文献_第5页

Integration of chemical precipitation and nanofiltration for sodium sulfate control and brine loop closure in a Chlor Alkali plant 氯碱厂化学沉淀和纳滤一体化控制硫酸钠和盐水循环

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-02-23 DOI: 10.1016/j.cscee.2026.101351

Marco Gaibor-Pacheco , Suanny Mosquera-Romero

In membrane-based chlor-alkali processes, brine recirculation is essential for improving operational sustainability; however, sodium sulfate (Na₂SO₄) accumulation in the loop hinders chlorine production. This study evaluates an integrated treatment scheme combining chemical precipitation and nanofiltration (NF) to remove Na₂SO₄ and enhance effluent reuse in a chlor-alkali plant in Guayaquil, Ecuador. Laboratory precipitation tests using real industrial effluent examined the influence of calcium chloride (CaCl₂) dosage, temperature, and pH. The best removal (49.3 ± 4.2% w/w) was achieved with 45 mL L⁻¹ CaCl₂ at 70 °C, pH 9-11, and 20 min of mixing, while efficiencies fell below 30% at 40-55 °C even with higher dosages (≥50 mL L⁻¹). Full-scale NF trials showed 72.8% w/w Na₂SO₄ rejection at 25 bar with 67.9% w/w water recovery. Both treated effluents were suitable for reintegration into the brine circuit. Mass balance analysis indicated that the combined process recovers up to 81.3% of the effluent, equivalent to 8051 m³ year⁻¹ of water and 1393 t year⁻¹ of NaCl, while mitigating saline discharges. The estimated capital cost (11,7021 USD) is offset by annual raw material savings of 93,964 USD. Overall, integrating chemical precipitation with membrane separation enhances process circularity, reduces freshwater consumption, and mitigates environmental impacts, while ensuring economic viability.

在膜基氯碱工艺中，盐水再循环对于提高操作可持续性至关重要；然而，硫酸钠（Na2SO4）在循环中的积累阻碍了氯的产生。本研究评估了厄瓜多尔瓜亚基尔（Guayaquil）氯碱厂化学沉淀和纳滤（NF）相结合的综合处理方案，以去除Na2SO4并提高废水回用。使用实际工业废水进行的实验室沉淀试验检查了氯化钙（CaCl2）用量、温度和pH的影响。在70 °C、pH 9-11和混合20分钟时，45 mL L -1 CaCl2达到了最佳去除率（49.3 ± 4.2% w/w），而在40-55 °C时，即使使用更高的用量（≥50 mL L -1），效率也降至30%以下。全尺寸NF试验表明，在25 bar条件下Na2SO4的截除率为72.8%，水回收率为67.9%。两种处理过的废水都适合重新进入盐水循环。质量平衡分析表明，该组合工艺可回收高达81.3%的出水，相当于8051 m3 /年的水和1393 t /年的NaCl，同时减少了盐水排放。预计的资本成本（11,7021美元）被每年节省的93,964美元的原材料所抵消。总体而言，将化学沉淀与膜分离相结合可以增强工艺循环，减少淡水消耗，减轻环境影响，同时确保经济可行性。

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引用次数: 0

Electromembrane and pervaporation technologies for the production of highly concentrated formic acid from captured CO2 valorization 电膜和渗透汽化技术用于从捕获的CO2气化中生产高浓度甲酸

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-03-03 DOI: 10.1016/j.cscee.2026.101358

Ainhoa Unzurrunzaga , Leire Lorenzo , Ainhoa Aguirre , María Fernández , Yolanda Belaustegui

Electro-membrane technologies to salt splitting chemicals such as potassium formate generated during the electrochemical conversion of captured CO₂ to obtain formic acid and potassium hydroxide represents a crucial pathway toward carbon neutrality and circular economy. The study demonstrated that the most effective configuration employed two cation exchange membranes (Nafion 324) to separate the anodic, cathodic and central compartments, with the feed solution circulated through the central compartment. This setup enabled potassium ions to migrate to the catholyte, where KOH was concentrated, while protons generated in the anodic compartment moved into the central compartment, maintaining an acidic pH (≈1) and allowing the concentration of formic acid. Optimal performance was achieved at 1500 A m⁻² and a circulated charge of 0.6715 F, yielding up to 100 g L⁻¹ of formic acid and 140 g L⁻¹ of potassium hydroxide. Additionally, pervaporation using a PERVAP 4101 membrane successfully broke the formic acid–water azeotrope, reaching concentrations up to 90%. This is the first study that demonstrates the production of highly concentrated formic acid from captured CO₂ by combining electrodialysis with monopolar membranes and pervaporation technologies.

电膜技术将捕获的二氧化碳在电化学转化过程中产生的甲酸钾等化学物质分解为甲酸和氢氧化钾，是实现碳中和和循环经济的重要途径。研究表明，最有效的配置是使用两个阳离子交换膜（Nafion 324）来分离阳极、阴极和中心隔间，进料溶液通过中心隔间循环。这种设置使钾离子迁移到阴极液中，在阴极液中KOH被浓缩，而在阳极室中产生的质子移动到中央室，保持酸性pH值（≈1），并允许甲酸的浓度。在1500 A m−2和0.6715 F的循环电荷条件下，甲酸的收率为100 g L−1，氢氧化钾的收率为140 g L−1。此外，使用perap 4101膜的渗透蒸发成功地打破了甲酸-水共沸物，达到了90%的浓度。这是第一个通过结合电渗析、单极膜和渗透蒸发技术，从捕获的二氧化碳中生产高浓度甲酸的研究。

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引用次数: 0

Modification of waste potato peels by combined acid-base treatment and its adsorption performance for the removal of phenol 酸碱复合处理对马铃薯废皮的改性及其对苯酚的吸附性能研究

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-02-16 DOI: 10.1016/j.cscee.2026.101348

Ntaote David Shooto, Patience Mapule Thabede

This study investigated the sorption capacity of potato peels for the removal of phenol from aqueous solution. The adsorption capacities of untreated potato peels (UPP) and acid-treated potato peels (APP) were compared with acid-base treated potato peels (ABPP). Characterisation of UPP, APP and ABPP by FTIR, SEM and XRD indicated that the surfaces of the adsorbents contain functional groups such as –OH, –C–O–C and –C–O. SEM images showed that the morphology of the adsorbents changed due to different chemical activations. The XRD patterns of APP and ABPP exhibited sharper peaks and higher intensities than those of UPP. The maximum sorption capacity of phenol on UPP, APP and ABPP was observed at pH 7. Adsorption isotherms showed that the Freundlich model best fitted the data, indicating multilayer sorption. The coefficient values for the PSO model were more appropriate for the uptake of phenol on all adsorbents. ABPP exhibited a higher sorption capacity for the removal of phenol, with an uptake capacity of 54.96 mg/g compared to UPP and APP.

研究了马铃薯皮对苯酚的吸附性能。对未经处理的马铃薯皮（UPP）、酸处理的马铃薯皮（APP）和酸碱处理的马铃薯皮（ABPP）的吸附性能进行了比较。利用FTIR、SEM和XRD对UPP、APP和ABPP进行了表征，结果表明吸附剂表面含有-OH、-C-O - c和-C-O等官能团。SEM图像显示，不同的化学活化方式改变了吸附剂的形貌。与UPP相比，APP和ABPP的XRD谱图表现出更强的峰和更高的强度。pH为7时，苯酚对UPP、APP和ABPP的最大吸附量。吸附等温线表明Freundlich模型最符合数据，表明吸附是多层的。PSO模型的系数值更适合于所有吸附剂对苯酚的吸收。与UPP和APP相比，ABPP对苯酚的吸附量为54.96 mg/g。

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引用次数: 0

Design constraints governing household-scale rice-straw biochar systems: The role of feedstock densification and particle-size selection 控制家庭规模稻秆生物炭系统的设计约束：原料致密化和粒度选择的作用

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-03-07 DOI: 10.1016/j.cscee.2026.101365

Nguyen Cong Manh , Nguyen Tri Quang Hung , Huynh Thi Ngoc Oanh , Yasushi Mori

Household-scale biochar systems are increasingly promoted for agricultural waste management and decentralized environmental applications; however, their design is often constrained by feedstock handling, material stability, and process simplicity rather than maximum functional performance. This study examines key design constraints in household-scale rice-straw biochar production, focusing on feedstock densification and particle-size selection under practical conditions. Rice straw was pyrolyzed in a household drum kiln with and without mechanical compression. Biochar yield, physicochemical properties, mechanical stability, and adsorption behavior were evaluated. Uncompressed rice-straw biochar showed poor structural integrity and fragmented during handling, preventing reproducible adsorption measurements. In contrast, compressed rice-straw biochar (BCRS) exhibited markedly improved yield and stability. At 400 °C for 2 h, BCRS achieved a mass yield of 66.7 ± 1.5%, compared with 31.6 ± 0.9% for uncompressed straw. Methylene blue adsorption showed clear particle-size dependence: finer particles enabled faster uptake, whereas coarser particles exhibited higher apparent capacity under batch conditions. These findings indicate that handling feasibility and material stability are primary design constraints, while adsorption performance serves as a secondary screening criterion in decentralized systems.

越来越多地推广家庭规模的生物炭系统用于农业废物管理和分散的环境应用；然而，它们的设计往往受到原料处理、材料稳定性和工艺简单性的限制，而不是最大的功能性能。本研究考察了家庭规模稻秆生物炭生产的关键设计约束，重点关注了实际条件下的原料致密化和粒度选择。采用机械压缩和不机械压缩两种方法，在家用滚筒窑中对稻草进行了热解。对生物炭产率、理化性质、机械稳定性和吸附行为进行了评价。未压缩的稻秆生物炭在处理过程中表现出较差的结构完整性和破碎性，妨碍了可重复性吸附测量。相比之下，压缩稻秆生物炭（BCRS）的产量和稳定性明显提高。在400 °C下发酵2 h， BCRS的产率为66.7 ± 1.5%，而未压缩秸秆的产率为31.6 ± 0.9%。亚甲基蓝吸附表现出明显的粒径依赖性：细颗粒能够更快地吸收，而粗颗粒在批量条件下表现出更高的表观容量。这些发现表明，处理可行性和材料稳定性是主要的设计约束条件，而吸附性能是分散系统的次要筛选标准。

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引用次数: 0

Groundwater hydrochemistry and identification of nitrate pollution sources in the Ouémé Delta (Southern-Benin) using dual isotopes (15N–NO3 and 18O–NO3) and a Bayesian isotope mixing model 基于双同位素（15N-NO3和18O-NO3）和贝叶斯同位素混合模型的南贝宁乌姆萨梅斯三角洲地下水水化学及硝酸盐污染源识别

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2025-11-28 DOI: 10.1016/j.cscee.2025.101303

Aoulatou Alassane Zakari , Kodjo Apelete Raoul Kpegli , Dadja-Toyou Masamaéya Gnazou , Abdoukarim Alassane , Bio Guidah Chabi , Fabrice Messan Amene Lawson , Nicaise Yalo , Daouda Mama , Moussa Boukari

The watershed of the Delta of Ouémé is part of the southern coastal sedimentary basin of Benin. Economic development in this region is essentially based on farming, fishing, and livestock breeding, which are activities that may lead to environmental pollution, including both surface and groundwater pollution. The major aim of the study is to examine the quality of groundwater and to find out the likely sources of pollution in this watershed, using an isotope mixing model (MixSIAR). The methodology applied calls on classical hydrochemical approaches, Self-Organizing Map (SOM), and stable nitrate isotopes (¹⁵N;¹⁸O) (allowing more accurate discrimination of contamination sources compared to hydrochemical methods). Results demonstrated that the origins of nitrate in groundwater are mainly from manure and sewage and soil nitrogen nitrification. The Bayesian model estimated the contribution of each source and the results have shown that manure and sewage represent the dominant contributors to groundwater nitrate (75.2 % and 87.3 % in the Mio-Pliocene and the Quaternary aquifers, respectively). Then, groundwater pollution during both the dry and rainy periods was mainly due to anthropogenic activities. These results highlight some major implications: (i) groundwater pollution is mainly of anthropogenic origin, calling for better control of agricultural and domestic practices; (ii) the isotopic approach coupled with advanced statistical methods is an effective tool for distinguishing and quantififing pollution sources; and (iii) the study provides a scientific basis for strengthening aquifer protection policies, limiting nitrate-related health risks and promoting sustainable management of water resources.

乌萨梅斯三角洲的分水岭是贝宁南部沿海沉积盆地的一部分。该地区的经济发展主要以农业、渔业和畜牧业为基础，这些活动可能导致环境污染，包括地表水和地下水污染。该研究的主要目的是使用同位素混合模型（MixSIAR）检查地下水的质量，并找出该流域可能的污染源。该方法采用了经典的水化学方法、自组织图（SOM）和稳定的硝酸盐同位素（15N;18O）（与水化学方法相比，可以更准确地识别污染源）。结果表明，地下水中硝酸盐的来源主要是粪肥、污水和土壤氮硝化作用。贝叶斯模型估算了各来源的贡献，结果表明，粪便和污水是地下水硝酸盐的主要来源（在中新-上新世和第四纪含水层分别占75.2%和87.3%）。干雨期地下水污染主要由人为活动引起。这些结果突出了一些主要影响：(i)地下水污染主要是人为造成的，要求更好地控制农业和家庭做法；（ii）同位素方法结合先进的统计方法是区分和量化污染源的有效工具；（三）该研究为加强含水层保护政策、限制与硝酸盐有关的健康风险和促进水资源的可持续管理提供了科学依据。

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引用次数: 0

Chlorine transport and decay analysis in water distribution systems using hydraulic simulation and physics- and chemistry-informed graph neural networks 利用水力模拟和物理化学信息图神经网络分析配水系统中的氯输运和衰变

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2025-12-26 DOI: 10.1016/j.cscee.2025.101321

Mostafa Khodakarami, Víctor R. Vásquez

Maintaining compliant chlorine residuals across water distribution networks is challenging because concentrations evolve under time-varying hydraulics, advective transport, and bulk and wall decay kinetics, while field monitoring is sparse. Physics-based simulators such as EPANET can represent these processes but require careful calibration and can be difficult to use for rapid, network-wide decision support, while purely data-driven models may violate basic transport and reaction constraints and often need dense measurements. This study develops a physics- and chemistry-informed graph neural network (GNN) that learns network-wide chlorine dynamics from hydraulic simulations while embedding domain features that represent connectivity, flow behavior, water age, and decay parameters. Two GNN architectures—a Graph Convolutional Network (GCN) and a Gated Graph Neural Network (GGNN)—are trained on features including pressure, demand, chlorine concentration, flow velocity, headloss, and decay coefficient that capture the system's hydraulic and chemical behavior. The approach is demonstrated on a subsection of Ward 4 in Reno, Nevada using a 240-h EPANET extended-period simulation dataset. Compared with a graph convolutional network baseline, the proposed GGNN improves predictive accuracy, reducing the mean absolute error from about 0.38 to 0.22 mg/L and the root mean square error from about 0.57 to 0.35 mg/L, while increasing coefficient of determination (R²) from about 0.93 to about 0.97. At a representative snapshot, results show that the GGNN significantly outperforms the GCN, achieving lower error and higher R² (>0.99), due to its iterative message-passing mechanism that captures long-range dependencies. Both models generalize well across hydraulic conditions, enabling accurate virtual sensing for real-time chlorine monitoring in sparsely instrumented networks.

在配水网络中维持符合要求的氯残留量是一项挑战，因为浓度会随着水力学、平流输送、体积和壁面衰变动力学的变化而变化，而现场监测很少。基于物理的模拟器（如EPANET）可以表示这些过程，但需要仔细校准，并且难以用于快速、全网范围的决策支持，而纯粹的数据驱动模型可能违反基本的传输和反应约束，通常需要密集的测量。本研究开发了一种基于物理和化学的图形神经网络（GNN），该网络可以从水力模拟中学习全网络范围的氯动力学，同时嵌入表示连通性、流动行为、水龄和衰变参数的域特征。两种GNN架构——图卷积网络（GCN）和门控图神经网络（GGNN）——根据压力、需求、氯浓度、流速、水头损失和衰减系数等特征进行训练，这些特征可以捕捉系统的水力和化学行为。使用240小时EPANET长周期模拟数据集，在内华达州里诺的Ward 4分区演示了该方法。与图卷积网络基线相比，所提出的GGNN提高了预测精度，平均绝对误差从约0.38降低到0.22 mg/L，均方根误差从约0.57降低到0.35 mg/L，而决定系数（R2）从约0.93提高到约0.97。在一个有代表性的快照中，结果表明GGNN明显优于GCN，实现了更低的误差和更高的R2 (>0.99)，这是由于其捕获远程依赖关系的迭代消息传递机制。这两种模型都可以很好地推广各种水力条件，从而在稀疏的仪器网络中实现精确的实时氯监测虚拟传感。

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引用次数: 0

Synthesis of MIL-100(Fe) derived α-Fe2O3 for fabrication of α-Fe2O3/ZIF-8 as photocatalyst of malachite green degradation MIL-100（Fe）衍生α-Fe2O3的合成制备α-Fe2O3/ZIF-8作为孔雀石绿降解光催化剂

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.2025.101320

Karelius Karelius , Ratna Ediati , Eko Santoso , Uripto Trisno Santoso , Nuhaa Faaizatunnisa , Rifdah Adya Salsabila , Marvin Horale Pasaribu , Retno Agnestisia

Development of highly efficient photocatalysts for the degradation of persistent and recalcitrant malachite green (MG) dye remains a significant challenge. In this study, mesoporous α-Fe₂O₃ was synthesized by calcining MIL-100(Fe) and subsequently encapsulated within ZIF-8 to form α-Fe₂O₃/ZIF-8 (FZF) composites. The resulting heterostructures exhibited a high surface area (566 m²/g), a narrow band gap (∼2.0 eV), improved charge separation, and strong adsorption capacity. Among the samples, FZF-25 achieved 99.35 % removal of 150 ppm MG within 80 min under UV irradiation and maintained excellent stability over four cycles. These findings highlight a promising MOF-derived α-Fe₂O₃/ZIF-8 approach that enables synergistic adsorption–photocatalysis process.

开发用于降解持久性和难降解性孔雀石绿染料的高效光催化剂仍然是一个重大挑战。在本研究中，通过煅烧MIL-100（Fe）合成介孔α-Fe2O3，并将其包裹在ZIF-8中形成α-Fe2O3/ZIF-8 （FZF）复合材料。所得异质结构具有高比表面积（566 m2/g）、窄带隙（~ 2.0 eV）、电荷分离改善和强吸附能力。其中，FZF-25在紫外照射下，在80 min内对150 ppm MG的去除率达到99.35%，并在4个循环内保持了良好的稳定性。这些发现突出了mof衍生的α-Fe2O3/ZIF-8方法的前景，该方法可以实现协同吸附-光催化过程。

引用次数: 0

Plastic waste-derived fuel in diesel engine for 4 kW power generation supporting smart grid stabilization 用于支持智能电网稳定的4千瓦发电的柴油发动机中的塑料废物衍生燃料

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-02-19 DOI: 10.1016/j.cscee.2026.101350

Paitoon Laodee , Preecha Sriprapakhan , Sakda Somkun , Nuwong Chollacoop , Pisit Maneechot

This research demonstrates the conversion of plastic waste, specifically LDPE and PE, into fuel oil using a pyrolysis process. The fuel produced was tested in a diesel engine connected to a 4-kW generator for smart grid power supply. Using a fixed-bed pyrolysis reactor, the process reduced the required operating temperature by 250–300 °C and achieved a plastic-to-oil conversion yield of 66.67%–75.52%. The produced pyrolysis oil showed physical properties close to standard diesel, with a density of 0.74941 g/cm³ and viscosity of 1.007 mm²/s, following ASTM standards. Its chemical composition included 80.98% carbon, 12.88% hydrogen, 0.21% nitrogen, and 5.93% oxygen, with a heating value of 36.46 kJ/kg. Economically, pyrolysis oil costs 20 baht/liter (0.57 USD), which is significantly cheaper than commercial diesel at 32.94 baht/liter (0.94 USD). While diesel oil showed higher engine efficiency (60.64%) compared to pyrolysis oil (49.41%), the study suggests that pyrolysis offers a promising solution for plastic waste management by producing a cost-effective, diesel-like alternative fuel suitable for energy applications.

本研究展示了利用热解过程将塑料废物，特别是LDPE和PE转化为燃料油。生产的燃料在一台柴油发动机中进行了测试，该柴油发动机与一台用于智能电网供电的4千瓦发电机相连。该工艺采用固定床热解反应器，操作温度降低250 ~ 300 ℃，塑料制油收率达到66.67% ~ 75.52%。所得热解油的物理性质接近标准柴油，密度为0.74941 g/cm3，粘度为1.007 mm2/s，符合ASTM标准。其化学成分为碳80.98%，氢12.88%，氮0.21%，氧5.93%，热值为36.46 kJ/kg。经济上，裂解油的成本为20泰铢/升（0.57美元），比商业柴油的32.94泰铢/升（0.94美元）便宜得多。尽管柴油的发动机效率（60.64%）高于热解油（49.41%），但该研究表明，热解为塑料废物管理提供了一个有希望的解决方案，它可以生产出一种具有成本效益的、类似柴油的替代燃料，适用于能源应用。

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引用次数: 0

Influence of plume rise parameterization on odor impact assessment: A case study of open biofilters 烟羽上升参数化对气味影响评价的影响：以开放式生物过滤器为例

Q1 Environmental Science

Case Studies in Chemical and Environmental Engineering

Pub Date : 2026-06-01 Epub Date: 2026-02-23 DOI: 10.1016/j.cscee.2026.101352

Francesca Tagliaferri , Laura Gianola , Laize Nalli de Freitas , Ademir Prata , Marzio Invernizzi

Advances in odor impact assessment increasingly rely on accurate atmospheric dispersion modelling. In this context, odor emissions from open biofilters are commonly modelled as non-buoyant area sources, implicitly neglecting plume rise effects. However, the biological activity within biofilters generates heat, producing emissions warmer than ambient air and potentially inducing buoyancy-driven plume rise. This study investigates the influence of plume rise parameterization on odor dispersion modelling from open biofilters using the CALPUFF model. A series of simulations is performed considering different source configurations (point, area, and buoyant area), and plume rise algorithms (Briggs and numerical). Results show that neglecting plume rise, as typically done in the literature, leads to substantial overestimations of odor concentrations compared to the other investigated scenarios. Including buoyancy effects produces outcomes that appear more physically consistent and representative of real emission behaviour, with comparable results between point and buoyant area sources. Within the spectrum of available algorithms, the semi-empirical formulation is inherently limited by simplifying assumptions, while numerical approaches exhibit enhanced physical robustness as they are subject to fewer constraints. Overall, the findings emphasize the importance of accounting for buoyancy in modelling open biofilters and suggest that common simplifications may lead to overly conservative outcomes.

气味影响评估的进展越来越依赖于准确的大气扩散模型。在这种情况下，开放式生物过滤器的气味排放通常被建模为非浮力区域源，隐含地忽略了羽流上升效应。然而，生物过滤器内的生物活动会产生热量，产生比周围空气更热的排放物，并可能导致浮力驱动的羽流上升。本研究利用CALPUFF模型研究了烟羽上升参数化对开放式生物过滤器气味分散建模的影响。考虑不同的源配置（点、面积和浮力面积）和羽流上升算法（Briggs和数值算法），进行了一系列模拟。结果表明，忽略烟羽上升，通常在文献中所做的，导致大量高估气味浓度相比，其他调查情景。包括浮力效应产生的结果在物理上似乎更一致，更能代表真实的排放行为，在点源和浮力区源之间具有可比较的结果。在可用算法的范围内，半经验公式本质上受到简化假设的限制，而数值方法表现出增强的物理稳健性，因为它们受到较少的约束。总的来说，研究结果强调了在模拟开放式生物过滤器时考虑浮力的重要性，并表明通常的简化可能导致过于保守的结果。

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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 : 2026-06-01 Epub 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