IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-11 DOI: 10.1016/j.fuel.2025.137958

Shuo Wang , Yifeng Wang , Tuan A. Ho , Yuntian Teng , Meng Ji , Mohammad Goli , Cheng Chen

Depleted oil and gas reservoirs, characterized by impermeable clay-rich caprocks, are promising sites for large-scale underground hydrogen storage (UHS), which is a key strategy to support hydrogen-based energy systems. However, experimental data on hydrogen storage in clay-rich geomaterials remain scarce. In this work, we experimentally investigated hydrogen adsorption and migration in clay-rich geomaterials in the presence of nitrogen and water under controlled temperatures. Experimental observations showed that hydrogen was adsorbed in dry illite. A dual-porosity transport model was developed to interpret hydrogen transport between large-pore and small-pore domains in illite. The large-pore domain is the space between clay particles (i.e., inter-particle space), whereas the small-pore domain is the nanoscale pore space between clay mineral layers (i.e., inter-layer or intra-particle space). In contrast, nitrogen showed no evidence of adsorption in dry illite because it cannot move into the small-pore domain due to the relatively large kinetic diameter, referred to as the molecular sieving effect. We found that 0.7–1.3 nm is the length scale regulating this molecular sieving effect, matching the interlayer spacing in illite, suggesting that nitrogen is a promising cushion gas in UHS, which aims to maintain adequate pressure in the reservoir for economic operations. In wetted illite, hydrogen was not adsorbed into the interlayer space due to the occupation of adsorption sites by interlayer water, which highlights the critical role of the clay hydration state in controlling hydrogen-clay interactions. Additionally, hydrogen adsorption experiments on crushed shale indicated that the shale surface possessed adsorption sites more favorable for hydrogen than for nitrogen. Through these experiments, we provide new insights into hydrogen storage mechanisms in clay-rich geomaterials and offer valuable laboratory data for evaluating the performance of large-scale UHS systems.

枯竭的油气储层以不透水的富粘土盖层为特征，是大规模地下储氢（UHS）的理想场所，这是支持氢基能源系统的关键战略。然而，在富含粘土的地质材料中储氢的实验数据仍然很少。在这项工作中，我们实验研究了氢在氮和水存在下在控制温度下在富粘土岩土材料中的吸附和迁移。实验结果表明，干伊利石吸附了氢气。建立了一种双孔隙输运模型来解释伊利石中氢在大孔和小孔域之间的输运。大孔隙域是粘土颗粒之间的空间（即颗粒间空间），而小孔隙域是粘土矿物层之间的纳米级孔隙空间（即层间或颗粒内空间）。相比之下，氮在干伊利石中没有表现出吸附的迹象，因为相对较大的动力学直径使其无法进入小孔域，称为分子筛分效应。研究发现，调节这种分子筛分效果的长度尺度为0.7 ~ 1.3 nm，与伊利石的层间间距相匹配，表明氮气在UHS中是一种很有前景的缓冲气体，其目的是保持储层足够的压力，以实现经济运行。在湿润的伊利石中，由于层间水占据了吸附位置，氢没有被吸附到层间空间中，这凸显了粘土水化状态在控制氢-粘土相互作用中的关键作用。此外，在破碎的页岩上进行的氢吸附实验表明，页岩表面具有更有利于氢而不是氮的吸附位点。通过这些实验，我们为富粘土岩土材料中的储氢机制提供了新的见解，并为评估大型UHS系统的性能提供了有价值的实验室数据。

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引用次数: 0

Synergistic improvement of cold flow properties in diesel fuel via urea dewaxing and pour point depressant addition 尿素脱蜡与降凝剂协同改善柴油冷流动性能

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-11 DOI: 10.1016/j.fuel.2025.137905

Yiqi Zhou , Jinyu Guo , Sanyan Du , Feifei Shi , Ke Chen , Bowen Xu , Hanwen Zhang , Jiabin Yin , Yuan Xue , Sheng Han

To address the reduced fluidity of diesel fuel caused by n-alkane precipitation at low temperatures, a collaborative multi-technology strategy was developed to enhance its cold flow properties (CFPs). In this study, urea dewaxing was combined with the addition of a nitrogen-containing pour point depressant (PPD) to achieve synergistic enhancement of CFPs. The effects of both treatments on key fuel characteristics were systematically investigated. These included physical properties such as density, surface tension, flash point, and kinematic viscosity, as well as combustion behavior represented by ignition delay and combustion duration. Polynomial fitting models were established to quantify the relationships between wax content and two indicators of CFPs: solid point (SP) and cold filter plugging point (CFPP). These models provided predictive insight into the compositional dependence of CFP performance. The synergistic mechanism of urea dewaxing and PPD addition was further examined through differential scanning calorimetry, low-temperature rheological analysis, and polarizing optical microscopy. Results showed that both SP and CFPP decreased markedly as wax content declined. When 2000 ppm of the nitrogen-containing PPD (NPPD) was added to dewaxed diesel with a wax content of 11.47 wt%, SP and CFPP reached optimal values of − 69 °C and − 49 °C, respectively. The ignition delay remained nearly constant, whereas the combustion duration was reduced by 2.55 %.

为了解决低温下正构烷烃沉淀导致柴油流动性降低的问题，研究人员开发了一种多技术协作策略，以提高柴油的冷流动性能（CFPs）。在本研究中，尿素脱蜡与添加含氮降凝剂（PPD）相结合，以实现CFPs的协同增强。系统地研究了两种处理对燃料关键特性的影响。这些参数包括密度、表面张力、闪点、运动粘度等物理特性，以及燃烧延迟和燃烧持续时间等燃烧行为。建立多项式拟合模型，量化蜡含量与CFPs固体点（SP）和冷滤堵塞点（CFPP）两项指标之间的关系。这些模型为CFP性能的成分依赖性提供了预测性见解。通过差示扫描量热法、低温流变学分析和偏光显微镜进一步研究了尿素脱蜡和PPD添加的协同作用机制。结果表明，SP和CFPP均随蜡含量的降低而显著降低。当含氮PPD （NPPD）在含蜡量为11.47 wt%的脱蜡柴油中添加2000 ppm时，SP和CFPP分别达到- 69°C和- 49°C的最佳值。点火延迟几乎保持不变，而燃烧持续时间减少了2.55%。

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引用次数: 0

Facet-dependent metal-support interactions of Ru/CeO2 dictate the activity for direct deoxygenation of m-cresol Ru/CeO2的面依赖性金属支持相互作用决定了间甲酚直接脱氧的活性

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-11 DOI: 10.1016/j.fuel.2025.137966

Yuxin Shang , Wenhui Yue , Zihao Liu , Ruoyu Zhang , Qingfeng Ge , Xinli Zhu

Catalytic hydrodeoxygenation (HDO) of lignin-derived phenolics selectively to aromatics represents an effective approach to utilize biomass for production of valuable chemicals. Oxophilic Ru is active for direct deoxygenation (DDO), but suffered from C-C hydrogenolysis to form undesirable CH₄. Herein, Ru supported on CeO₂ with varying morphologies (Octahedron, Cube and Rod dominantly exposing (111), (100) and (110) facets, respectively) was investigated for the facet dependent metal-support interactions and tested for HDO of m-cresol at 350 °C and atmospheric pressure. Compared to Ru/CeO₂-Octa and Ru/CeO₂-Cube, the stronger Ru-CeO₂ interactions of Ru/CeO₂-Rod lead to higher Ru dispersion and more Ru/CeO_x interfacial perimeter sites with the highest density of oxygen vacancies. The reduced Ru size on Ru/CeO₂-Rod inhibited C–C hydrogenolysis toward CH₄ on Ru terrace site, and the increased Ru/CeO_x interfacial perimeter sites with abundant oxygen vacancies significantly improved the DDO of m-cresol to aromatics (mainly toluene). Consequently, the Ru/CeO₂-Rod exhibited the highest intrinsic HDO reaction rate of 13.35 µmol g_cat⁻¹ min⁻¹, which is ∼1.7 and ∼2.3 times higher than that on Ru/CeO₂-Cube and Ru/CeO₂-Octa, respectively. This work indicates that the property of Ru/CeO_x interface can be tuned by the predominantly exposed facets via tailoring the morphology of CeO₂, which can be used to control the reactions during HDO and therefore to facilitate the DDO of phenolics to aromatics.

木质素衍生酚类化合物选择性催化加氢脱氧生成芳烃是利用生物质生产有价值化学品的有效途径。亲氧Ru对直接脱氧（DDO）有活性，但会发生C-C氢解生成不需要的CH4。本文研究了钌在不同形貌的CeO2上（八面体、立方体和棒状分别主要暴露（111）、（100）和（110）面）的金属-载体相互作用，并测试了间甲酚在350℃和常压下的HDO。与Ru/CeO2-Octa和Ru/CeO2-Cube相比，Ru/CeO2-Rod的Ru- ceo2相互作用更强，导致Ru弥散度更高，Ru/CeOx界面周长位置更多，氧空位密度最高。Ru/ ceo2 -棒上Ru尺寸的减小抑制了Ru阶地上C-C向CH4的氢解，而Ru/CeOx界面周长空位的增加显著提高了间甲酚对芳烃（主要是甲苯）的DDO。结果表明，Ru/CeO2-Rod的HDO反应速率最高，为13.35µmol gcat−1 min−1，分别是Ru/CeO2-Cube和Ru/CeO2-Octa的1.7倍和2.3倍。这项工作表明，Ru/CeOx界面的性质可以通过调整CeO2的形态来调整主要暴露的面，这可以用来控制HDO过程中的反应，从而促进酚类化合物向芳烃的DDO。

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引用次数: 0

The effect of swirler structure on the combustion characteristics of ammonia-hydrogen flames in a miniature swirl combustor 旋流器结构对微型旋流燃烧室氨氢火焰燃烧特性的影响

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-11 DOI: 10.1016/j.fuel.2025.137962

Xiao Yang , Keqin Sheng , Mohan Li , Mengyu Wang , Dongtai Han , Xuanqi Liu , Li Yang , Fang Liu

Ammonia–hydrogen combustion has attracted significant attention as a clean energy strategy, where hydrogen addition effectively mitigates the poor combustion characteristics of ammonia. Swirl-stabilized flames, with enhanced mixing and robust flame anchoring, are well-suited for ammonia–hydrogen combustion systems. This study examines the influence of swirler blade angle (0°–60°) and bluff-body trailing-end diameter (5–9 mm) on ammonia–hydrogen flame structures, flammability limits, OH* chemiluminescence, and NO emissions in a miniature swirl combustor characterized by compact confinement and a high surface-to-volume ratio, which intensifies heat losses and flame–wall interactions. Experiments and CFD simulations reveal that moderate swirl intensities (30°–45°) broaden flammability limits, suppress flame lift-off, and enhance combustion stability, while excessively weak or strong swirl degrades performance. A 7 mm bluff-body trailing-end diameter provides optimal stability and the broadest flammability limits. NO emissions decrease by up to 45 % with optimized blade angles and 23 % with larger bluff-body diameters at an equivalence ratio of 0.7. OH* chemiluminescence reveals that swirl intensity and bluff body geometry strongly govern heat release distribution and localized high-temperature zones, affecting flame structure and NO formation. Numerical simulations further elucidate flame front evolution, temperature fields, and stabilization mechanisms. These findings provide design guidance for low-emission, carbon-free micro power systems utilizing ammonia-hydrogen fuel blends.

氨氢燃烧作为一种清洁能源策略备受关注，其中加氢有效缓解了氨的不良燃烧特性。涡流稳定火焰，增强混合和强大的火焰锚定，非常适合氨氢燃烧系统。本研究考察了旋流器叶片角度（0°-60°）和翼体尾端直径（5-9 mm）对氨氢火焰结构、可燃性极限、OH*化学发光和NO排放的影响。该研究采用了一种小型旋流燃烧室，其结构紧凑，表面体积比高，从而加剧了热损失和火焰-壁面相互作用。实验和CFD模拟表明，中等涡流强度（30°-45°）可拓宽可燃性极限，抑制火焰上升，提高燃烧稳定性，而过弱或过强的涡流则会降低燃烧性能。7毫米的崖体尾端直径提供了最佳的稳定性和最广泛的可燃性限制。优化叶片角度时，NO排放量可减少45%，在等效比为0.7时，较大的崖体直径可减少23%。OH*化学发光表明，旋流强度和钝体几何形状强烈地控制着热释放分布和局部高温区，影响火焰结构和NO的形成。数值模拟进一步阐明了火焰锋面演化、温度场和稳定机制。这些发现为利用氨氢燃料混合物的低排放、无碳微动力系统的设计提供了指导。

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引用次数: 0

Micro-CT based observations of pore structure in tight sandstone and residual oil under CO2 and water flooding CO2和水驱作用下致密砂岩和剩余油孔隙结构的微ct观测

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-10 DOI: 10.1016/j.fuel.2025.137764

Sisi Chen , Hongyan Yu , Wangyikun Fan , Muhammad Arif

Oil recovery efficiency in tight sandstone reservoirs is closely linked to fluid flow behavior, which is influenced by the intricate pore-throat structures and varying displacement methods employed. The objective of this study is to investigate the pore-scale distribution and recovery behavior of residual oil in tight sandstone during brine and CO₂ flooding. Two tight sandstone samples (in the Longdong area of the Ordos Basin) were analyzed using high-resolution in-situ micro-computed tomography (micro-CT) with a voxel size of 3 µm. Three-dimensional reconstructions were employed to quantify the morphology of residual oil, pore-throat structure, and recovery efficiency at various stages of flooding. The oil primarily appears in cluster and porous forms during brine displacement, breaking into smaller droplets and film structures as brine saturation progresses. In contrast, CO₂ displacement more effectively reduced cluster oil, but led to a higher proportion of challenging film residual oil (19%). Quantitative analysis revealed that CO₂ displacement achieved a higher final recovery rate of 52.35%, compared to 48.29% for brine. This study provides the first direct, quantitative comparison of recovery efficiency between CO₂ and brine flooding in tight sandstone using real-time micro-CT imaging. The findings clarify the morphological “cost” of CO₂ displacement and offer new experimental insights for validating pore-scale numerical models and optimizing enhanced oil recovery in low-permeability reservoirs.

致密砂岩储层的采收率与流体流动特性密切相关，流体流动特性受复杂的孔喉结构和不同驱替方法的影响。研究了致密砂岩在盐水和CO2驱过程中的孔隙尺度分布及剩余油的采收率规律。采用高分辨率原位微计算机断层扫描（micro-CT）对鄂尔多斯盆地陇东地区2个致密砂岩样品进行了体素尺寸为3µm的分析。利用三维重建技术量化了不同驱替阶段剩余油形态、孔喉结构和采收率。在盐水驱替过程中，油主要以簇状和多孔形式出现，随着盐水饱和度的提高，油会分解成更小的液滴和膜状结构。相比之下，CO2驱替更有效地减少了簇油，但导致了更高比例的挑战膜残余油（19%）。定量分析表明，CO2驱替的最终采收率为52.35%，高于盐水驱替的48.29%。该研究首次利用实时微ct成像技术对致密砂岩中CO2驱和盐水驱的采收率进行了直接、定量的比较。该研究结果阐明了CO2驱替的形态“成本”，并为验证孔隙尺度数值模型和优化低渗透油藏的提高采收率提供了新的实验见解。

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引用次数: 0

Catalytic deoxygenation of oils derived from black soldier fly larvae and sardine and squid wastes for renewable and sustainable biojet fuel production 从黑虻幼虫和沙丁鱼和鱿鱼废物中提取的油的催化脱氧用于可再生和可持续的生物喷气燃料生产

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-10 DOI: 10.1016/j.fuel.2025.137960

A.S. Silitonga , A.H. Sebayang , Siti Maretia Benu , T.M.I. Riayatsyah , Bela Nurulita , Bidattul Syirat Zainal , R.S.R.M. Hafriz , Fazril Ideris , Nandy Putra , Deswita , Oki Muraza

The development of sustainable drop-in aviation fuels from non-edible, waste-based feedstocks is crucial for decarbonising the aviation industry. In this study, the catalytic deoxygenation of black soldier fly (BSF) larvae-, sardine waste-, and squid waste-derived oils was investigated using calcined dolomite–nickel oxide (DO–NiO) catalyst to produce renewable and sustainable biojet fuels. The fatty acid analysis revealed that lauric acid (28.06 %), palmitic acid (20.19 %), and myristic acid (16.00 %) were the predominant constituents of the BSF larvae oil, while high volumes of behenic acid (C22:0, 26.67 %) and arachidic acid (C20:0, 38.12 %) were present in the sardine waste oil. Crude oil analysis showed that the BSF larvae, sardine waste, and squid waste oils had a kinematic viscosity of 35.693, 28.889, and 27.768 mm²/s, respectively, and an acid value of 9.97, 32.58, and 16.32 mg KOH/g, respectively. The iodine values indicated that the oils were suitable as a feedstock for the production of biojet fuels. Upgrading of the oils with DO–NiO catalyst significantly enhanced the quality of the fuels, which led to the high-quality waste-derived biojet fuels with high flash points (up to 41 °C), and acidity below 0.1 mg KOH/g, which fulfilled the specifications defined by the ASTM D1655 standard. Upon blending with 10 % of Jet A-1 commercial aviation fuel, the density, kinematic viscosity, and calorific values of the resulting biojet fuel blends (BSFAV10, SAOAV10, SQAV10) were close to those specified for synthetic sustainable aviation fuels. These findings underscore the viability of waste oil valorisation via low-cost DO–NiO catalysis for the production of drop-in renewable biojet fuels, which aligned with circular economy principles and aviation sustainability goals.

从不可食用的、基于废物的原料中开发可持续的一次性航空燃料对航空业脱碳至关重要。本研究采用煅烧白云石-氧化镍（DO-NiO）催化剂，研究了黑虻（BSF）幼虫、沙丁鱼废物和鱿鱼废物衍生油的催化脱氧制备可再生和可持续的生物喷气燃料。脂肪酸分析表明，月桂酸（28.06%）、棕榈酸（20.19%）和肉豆酱酸（16.00%）是沙丁鱼幼虫油的主要成分，而沙丁鱼废油中含有大量的失净酸（C22:0, 26.67%）和花生酸（C20:0, 38.12%）。原油分析表明，BSF幼虫、沙丁鱼废油和鱿鱼废油的运动粘度分别为35.693、28.889和27.768 mm2/s，酸值分别为9.97、32.58和16.32 mg KOH/g。碘值表明，这些油适合作为生产生物喷气燃料的原料。采用DO-NiO催化剂对油进行升级处理，显著提高了燃料的质量，从而生产出高闪点（高达41°C）、酸度低于0.1 mg KOH/g的高质量废物衍生生物喷气燃料，符合ASTM D1655标准的规定。在与10%的Jet A-1商用航空燃料混合后，所得生物航空燃料混合物（BSFAV10, SAOAV10, SQAV10）的密度，运动粘度和热值接近合成可持续航空燃料的规定。这些发现强调了通过低成本DO-NiO催化生产可再生生物喷气燃料的废油增值的可行性，这符合循环经济原则和航空可持续发展目标。

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引用次数: 0

Damkohler number effect on nanoparticle seeded blended hydrogen flames 纳米粒子混合氢火焰的Damkohler数效应

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-10 DOI: 10.1016/j.fuel.2025.137963

Rahat Mollick , Chenrui Ma , Jingwen Fu , Yun Huang , Jianan Zhang , Hongtao Ding , Albert Ratner

This study investigates the effects of nanoparticle seeding on flame stabilization and flame front structure in premixed Methane and Methane-Hydrogen flames using a low-swirl burner. Acetylene black nanoparticles are introduced at 0.01 mg/s across 36 test conditions, spanning three fuel blends and five equivalence ratios (Φ = 0.6–1.1). High-speed color imaging and Hydroxyl Radical Planar Laser-Induced Fluorescence (OH-PLIF) diagnostics capture flame dynamics, while custom MATLAB processing quantifies curvature and flame surface density. Seeding consistently narrows the curvature probability density function (PDF), reduces curvature variance (up to 31 %), and increases PDF peaks (up to 34.6 %), consistent with reduced geometric wrinkling and a more coherent flame surface. While Hydrogen addition extends lean flammability, its combination with seeding provides additional but diminishing stabilization. Flame brush comparisons confirm that seeding promotes smoother, spatially uniform flame structures without altering global geometry. These findings support nanoparticle seeding as a passive strategy for improving flame stability in lean-premixed combustion systems.

采用低旋流燃烧器研究了纳米颗粒播种对甲烷和甲烷-氢预混火焰火焰稳定性和火焰前缘结构的影响。在36个测试条件下，以0.01 mg/s的速度引入乙炔黑色纳米颗粒，包括三种燃料混合物和五种等效比（Φ = 0.6-1.1）。高速彩色成像和羟基自由基平面激光诱导荧光（OH-PLIF）诊断捕捉火焰动力学，而定制的MATLAB处理量化曲率和火焰表面密度。播种持续缩小曲率概率密度函数（PDF），减少曲率方差（高达31%），增加PDF峰（高达34.6%），与减少几何起皱和更连贯的火焰表面一致。虽然加氢延长了低可燃性，但与种子的结合提供了额外的稳定性，但稳定性会降低。火焰刷比较证实播种促进平滑，空间均匀的火焰结构，而不改变全局几何形状。这些发现支持纳米颗粒播种作为一种被动策略，以改善稀预混燃烧系统的火焰稳定性。

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引用次数: 0

Comparative study of water-cooled wall supercritical and subcritical operation characteristics during deep peaking of 350 MW supercritical boiler 350mw超临界锅炉深度调峰时水冷壁超临界与亚临界运行特性对比研究

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-10 DOI: 10.1016/j.fuel.2025.137950

Shao Huaishuang , Wang Yibo , Shen Tao , Wei Guohua , Shi Chengfan , Deng Shifeng , Zhao Qinxin

The rapid growth of renewable energy power generation makes coal-fired power plants operate in a long-term deep peaking state. Furthermore, frequent load fluctuations increase the risk of local over-temperature tube bursts in the water-cooled wall. In this paper, a set of water-cooled wall hydrodynamic and combustion-side heat load distribution coupling calculation models is developed using MATLAB. This model is used to comparatively analyze the flow distribution and heat transfer characteristics of a 350 MW boiler operating at 75 % supercritical condition peaking to 50 % subcritical condition. By comparing the water-cooled wall’s outlet temperature, the prediction results of the developed combustion-hydrodynamic coupling model show great agreement with the measured boiler operation data. The relative errors of the water-cooled wall outlet temperature under supercritical and subcritical operating conditions are all within 10 %. The flow deviation of the spiral panels increases after changing from supercritical to subcritical pressure operation. However, while the percentage of pressure drop in the vertical panels changes, the total pressure drop remains basically unchanged, preventing an increase in flow deviation. The high-temperature zone on the wall occurs at the left wall of the upper furnace under both supercritical and subcritical conditions. The maximum metal outer-wall temperatures are 736.1 K and 779.7 K at 75 % and 50 % Turbine Heat Acceptance (THA) loads, respectively. The overall furnace wall temperature is higher under supercritical load operation than under subcritical load operation, but the maximum outer-wall temperature is higher under subcritical load. Dry out occurs in the vertical panels under 50 % THA load, indicating that the water-cooled wall is at high risk of over-temperature in subcritical peaking conditions.

可再生能源发电的快速增长使得燃煤电厂长期处于深调峰状态。此外，频繁的负荷波动增加了水冷壁局部过热爆管的风险。本文利用MATLAB建立了一套水冷壁流动力与燃烧侧热负荷分布耦合计算模型。利用该模型对比分析了350mw锅炉在75%超临界工况、调峰至50%亚临界工况下的流动分布和换热特性。通过对水冷壁出口温度的比较，所建立的燃烧-水动力耦合模型的预测结果与锅炉实际运行数据吻合较好。超临界和亚临界工况下的水冷壁出口温度相对误差均在10%以内。螺旋板由超临界转亚临界后，其流动偏差增大。然而，当垂直板压降百分比发生变化时，总压降基本保持不变，阻止了流动偏差的增加。在超临界和亚临界条件下，炉膛壁上的高温区都出现在炉膛上部的左壁上。在75%和50%涡轮热接受（THA）负荷下，金属外墙最高温度分别为736.1 K和779.7 K。超临界负荷运行时炉壁整体温度高于亚临界负荷运行时炉壁最高温度，但亚临界负荷运行时炉壁最高温度更高。在50% THA荷载下，垂直板出现干干现象，说明在亚临界峰值工况下，水冷壁存在过温风险。

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引用次数: 0

Optimization of the oxidation reactivity of pyrolytic residual char from end-of-life photovoltaic backsheet based on Front-End pyrolysis regulation 基于前端热解调控的光伏背板热解残焦氧化反应性优化

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-10 DOI: 10.1016/j.fuel.2025.137833

Qingyu Liu, Renjie Zou, Guangqian Luo, Haoyu Zhang, Shukai Pan, Xian Li, Hong Yao

Pyrolysis is a promising technology for separating and recycling the end-of-life (EOL) photovoltaic (PV) modules, but the residual char generated from the pyrolysis of backsheet reduces the quality of recovered materials. Oxidation is expected to achieve deep removal of residual char. However, previous studies have found that pyrolytic residual char has poor reactivity, resulting in a time- and energy-intensive removal process. Therefore, this study proposes a front-end pyrolysis-based regulation method to enhance the oxidative reactivity of residual char. A microfluidized bed coupled with mass spectrometry (MFB-MS) system was used to explore the oxidation characteristics and kinetic parameters of the residual char, which was obtained from Tedlar-Polyethylene terephthalate-Tedlar (TPT) backsheet under varying pyrolysis temperatures and times. Results showed that the oxidative reactivity of TPT char initially decreased and subsequently increased with rising pyrolysis temperature, and shortened pyrolysis time consistently enhanced reactivity. Key physical and chemical properties of TPT char were systematically analyzed to reveal the mechanisms governing char reactivity. It was found that the reactivity was jointly governed by the decomposition of oxygen-containing functional groups and the development of active sites. Kinetic analysis indicated that the oxidative activation energy of backsheet char reduced from 139.7 kJ/mol to 119.9 kJ/mol through pyrolysis regulation.

热解是一种很有前途的分离和回收废旧光伏组件的技术，但背板热解产生的残余炭降低了回收材料的质量。氧化有望达到深度去除残余炭的目的。然而，以往的研究发现，热解残炭的反应性较差，导致其去除过程耗时耗力。因此，本研究提出了一种基于前端热解的调控方法来提高残炭的氧化反应性。采用微流化床-质谱联用（MFB-MS）系统对泰德拉-聚对苯二甲酸乙二醇酯-泰德拉（TPT）背片在不同热解温度和时间下的残余炭氧化特性和动力学参数进行了研究。结果表明：随着热解温度的升高，TPT焦的氧化反应活性先降低后升高，热解时间的缩短使反应活性持续增强。系统分析了TPT炭的主要理化性质，揭示了控制炭反应性的机理。结果表明，反应活性受含氧官能团的分解和活性位点的发育共同控制。动力学分析表明，通过热解调节后，炭的氧化活化能从139.7 kJ/mol降低到119.9 kJ/mol。

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引用次数: 0

One-pot synthesis of porphyrin-imidazole-based ionic hypercrosslinked polymers as heterogeneous catalyst for efficient cycloaddition of CO2 with epoxides 一锅法合成卟啉-咪唑基离子高交联聚合物，作为CO2与环氧化物高效环加成的异相催化剂

IF 7.5 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-12-10 DOI: 10.1016/j.fuel.2025.137935

Huibing Shan , Jianjun Wang , Zhichun Shi , Jiao Liu , Yu Zang , Toshiki Aoki

Background

With the escalation of the global climate warming crisis, achieving the integration of CO₂ capture and utilization remains a substantial challenge. The purpose of this research is to develop a stable and highly efficient heterogeneous POP catalyst which can achieve the fixation of CO₂ under mild and metal-free conditions.

Methods

In this work, a series of novel ionic hypercrosslinked polymers (IHCP-Cls) were prepared by the one-pot quaternization and Friedel-Crafts alkylation for catalyzing CO₂ cycloaddition. The obtained IHCP-Cls contains not only contain hydrogen bond donors and cationic centers that can well interact with the epoxides and CO₂ molecules, but also possesses the nucleophilic Cl^- anions that can effectively facilitate the opening of the substrate and achieve the cycloaddition reaction.

Significant findings

The obtained IHCPs can achieve a catalytic yield of up to 99.7 % for pure CO₂ and 75.1 % for diluted CO₂ (simulating flue gas). Moreover, it also demonstrates a remarkable reusability that can retain 93 % of its catalytic yield and 98 % of its selectivity even after seven cycles. DFT theoretical calculations reveal that the porphyrin units along with the cations and anions in imidazole moiety plays a crucial role in substrate ring-opening and CO₂ activation during the catalytic process.

随着全球气候变暖危机的升级，实现二氧化碳捕集与利用一体化仍然是一项重大挑战。本研究的目的是开发一种稳定、高效的多相POP催化剂，在温和、无金属的条件下实现CO2的固定。方法采用一锅季铵化和Friedel-Crafts烷基化法制备了一系列新型离子超交联聚合物（IHCP-Cls），用于催化CO2环加成反应。得到的IHCP-Cls不仅含有氢键供体和阳离子中心，可以很好地与环氧化物和CO2分子相互作用，而且还具有亲核的Cl-阴离子，可以有效地促进底物的打开，实现环加成反应。所获得的IHCPs对纯二氧化碳的催化收率可达99.7%，对稀释二氧化碳（模拟烟气）的催化收率可达75.1%。此外，它还具有显著的可重复使用性，即使经过7次循环也能保持93%的催化收率和98%的选择性。DFT理论计算表明，卟啉单元与咪唑部分的阳离子和阴离子在催化过程中对底物开环和CO2活化起着至关重要的作用。

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引用次数: 0

Fuel最新文献

Background

Methods

Significant findings