Chemical Engineering Science最新文献

Selective depression of calcite through aluminum-assisted phosphonate interfacial regulation for enhanced cassiterite flotation 铝辅助膦酸盐界面调控对方解石的选择性抑制促进锡石浮选

IF 5.1 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-10-15 DOI: 10.1016/j.ces.2026.125384

Yongchao Miao, Yanyu Tang, Panjin Hu, Wenping Chen, Qicheng Feng, Qinghuang Bao, Qian Zhang, Ye Wang, Wenhang Yang

Selective flotation separation of cassiterite from calcite remains challenging because both minerals exhibit similar flotation responses toward conventional fatty acid collectors. In this study, a novel Al³⁺/ATMP combined depressant system was developed for the selective flotation separation of cassiterite from calcite using sodium oleate (NaOL) as the collector. Under the selected optimum conditions within the investigated range (pH 9.0, NaOL concentration of 1.75 × 10⁻⁴ mol/L, total Al³⁺/ATMP dosage of 10 mg/L, and Al³⁺:ATMP mass ratio of 1:3), the recovery of calcite decreased to approximately 8%, whereas cassiterite recovery remained around 90%. Surface characterization revealed distinct interfacial responses of calcite and cassiterite to the combined Al³⁺/ATMP treatment. Calcite exhibited a pronounced increase in hydrophilicity, whereas the NaOL-induced hydrophobicity of cassiterite was largely preserved. Residual TOC measurements showed differences in the organic carbon remaining in the supernatants after reagent treatment, providing complementary information on the overall behavior of the reagent systems without distinguishing the individual contributions of NaOL and ATMP. Solution chemistry analysis indicated that the Al³⁺ introduced through aluminum sulfate underwent extensive hydrolysis at pH 9.0, with Al(OH)₃ representing a predominant Al-containing species under the investigated conditions. XPS results revealed the presence of Al- and P-containing species on the treated calcite surface, supporting their involvement in the interfacial modification of calcite and the association of ATMP with the modified surface. Furthermore, under identical simulation conditions, molecular dynamics simulations suggested a greater tendency for the modeled Al(OH)₃ and neutral ATMP species to accumulate near the calcite interface than near cassiterite, accompanied by differences in the relative distribution and mobility of interfacial water molecules. Together with the experimental observations, these qualitative and comparative simulation results support the proposed preferential interfacial association of hydrolyzed Al-containing species and ATMP with calcite, contributing to its selective depression. This work provides an effective strategy for the selective flotation separation of cassiterite from calcite and offers insights into the design of metal ion–organic phosphonate depressant systems for complex oxide mineral flotation.

锡石和方解石的选择性浮选分离仍然具有挑战性，因为这两种矿物对传统的脂肪酸捕收剂表现出相似的浮选反应。以油酸钠（NaOL）为捕收剂，研制了一种新型Al3+/ATMP复合抑制剂体系，用于锡石和方解石的选择性浮选分离。在pH为9.0、NaOL浓度为1.75 × 10−4 mol/L、Al3+/ATMP总投加量为10 mg/L、Al3+:ATMP质量比为1:3的条件下，方解石的回收率降至8%左右，锡石的回收率保持在90%左右。表面表征表明方解石和锡石对Al3+/ATMP联合处理有明显的界面反应。方解石的亲水性明显增强，而naol诱导的锡石的疏水性基本保留。剩余TOC测量显示了试剂处理后上清中剩余有机碳的差异，提供了试剂系统总体行为的补充信息，而没有区分NaOL和ATMP的单独贡献。溶液化学分析表明，通过硫酸铝引入的Al3+在pH为9.0时发生了广泛的水解，其中Al(OH)3为主要的含Al物质。XPS结果显示，处理后的方解石表面存在含Al和含p物质，支持它们参与方解石的界面修饰以及ATMP与修饰表面的关联。此外，在相同的模拟条件下，分子动力学模拟表明，与锡石相比，模拟的Al(OH)3和中性ATMP更倾向于在方解石界面附近积聚，同时界面水分子的相对分布和迁移率也存在差异。结合实验观察，这些定性和比较模拟结果支持了解方解石与ATMP的优先界面关联，有助于其选择性抑制。本研究为锡石与方解石的选择性浮选分离提供了一种有效的策略，并为复杂氧化物矿物浮选金属离子-有机膦酸盐抑制剂体系的设计提供了见解。

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引用次数: 0

Synergistic hydrocarbon surfactant system for enhancing CO2-oil miscibility: Insights from vanishing interfacial tension experiments 增效碳氢表面活性剂体系增强CO2-oil混相：来自消失界面张力实验的见解

IF 5.1 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-10-14 DOI: 10.1016/j.ces.2026.125371

Jiawei Zhao, Shaopeng Li, Songyan Li

As carbon capture, utilization, and storage (CCUS) technologies advance, CO₂ flooding has gained significant attention due to its dual benefits of enhanced oil recovery (EOR) and geological CO₂ sequestration. However, for high-temperature reservoirs and crude oils enriched in heavy components, the MMP of the CO₂-crude oil system is often high, which makes miscible flooding difficult to achieve under reservoir conditions. In this study, tri-isobutyl citrate (TIBC) was synthesized via acid-catalyzed esterification and characterized by FTIR and ¹H NMR to confirm its structure. TIBC was then blended with Span 80 to construct a miscibility-enhancing system dominated by hydrocarbon chains and oxygen-containing functional groups, referred to as the system (TS), aimed at reducing the MMP of the CO₂-crude oil system. The results indicate that when the mass ratio of TIBC to Span 80 is 3:7 and the total concentration is 1.0 wt%, the system exhibits the optimal performance, reducing the MMP by 18.91%. Analysis of oil droplet interfacial behavior reveals synergistically improved CO₂ dissolution and extraction in crude oil, leading to continuous IFT reduction. The system ultimately reaches near-miscible or miscible conditions. The findings provide important guidance for EOR through CO₂ miscible flooding and for promoting CO₂ utilization and geological sequestration

随着碳捕集、利用和封存（CCUS）技术的进步，二氧化碳驱油因其提高石油采收率（EOR）和地质封存二氧化碳的双重优势而备受关注。然而，对于高温油藏和富含重质组分的原油，co2 -原油体系的MMP往往很高，这使得在油藏条件下难以实现混相驱。本研究采用酸催化酯化法合成了柠檬酸三异丁酯（TIBC），并用FTIR和1H NMR对其结构进行了表征。然后将TIBC与Span 80混合，构建以烃链和含氧官能团为主的混相增强体系（TS），旨在降低co2 -原油体系的MMP。结果表明，当TIBC与Span 80的质量比为3:7，总浓度为1.0 wt%时，体系性能最佳，MMP降低18.91%。对油滴界面行为的分析表明，协同作用改善了原油中CO2的溶解和萃取，导致IFT持续降低。该体系最终达到近混相或混相条件。研究结果对CO2混相驱提高采收率、促进CO2的利用和地质封存具有重要的指导意义

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引用次数: 0

3D molecular representation learning for organic mixtures: Viscosity and density prediction 三维分子表示学习有机混合物：粘度和密度预测

IF 4.7 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-10-14 DOI: 10.1016/j.ces.2026.125375

Haicheng Qu, Yanyi Su, Ning Wang, Shangqian Chen, Zhifeng Gao, Jun Cheng, Qi Ou

The viscosity and density of organic mixtures are essential properties for designing lubricants, solvents, and heat transfer fluids. In engineering practice, formulating a functional fluid requires understanding how these properties change with composition and temperature. However, exhaustive experimental characterization across the full parameter space is impractical due to the vast number of possible species and combinations. Here we introduce a mixture-aware 3D molecular representation learning strategy, built upon a pre-trained molecular encoder, that jointly encodes component structures, mole fractions, and temperature to achieve accurate predictions for organic mixtures. Fine-tuning on publicly available datasets covering a wide range of binary organic mixtures yields test-set R2 values of 0.973 for dynamic viscosity and 0.996 for density, significantly outperforming traditional machine learning baselines. Beyond overall accuracy, the model reproduces non-monotonic viscosity changes upon mixing that are not represented by simple linear or logarithmic mixing rules. The model is further used to examine how branching and cyclic or aromatic structures affect predicted viscosity–temperature behavior in the evaluated hydrocarbon systems. These results establish a practical framework for predicting viscosity and density within the represented chemical domain and illustrate its potential for screening organic-mixture formulations.

有机混合物的粘度和密度是设计润滑剂、溶剂和传热流体的基本特性。在工程实践中，要配制一种功能性流体，就需要了解这些性质是如何随成分和温度变化的。然而，由于大量可能的物种和组合，在整个参数空间中进行详尽的实验表征是不切实际的。在这里，我们介绍了一种混合物感知的3D分子表示学习策略，该策略建立在一个预训练的分子编码器上，该编码器联合编码组分结构、摩尔分数和温度，以实现对有机混合物的准确预测。对公开可用的数据集进行微调，涵盖范围广泛的二元有机混合物，测试集的动态粘度R2值为0.973，密度R2值为0.996，显著优于传统的机器学习基线。除了整体精度之外，该模型再现了混合后的非单调粘度变化，这些变化不是由简单的线性或对数混合规则表示的。该模型进一步用于研究分支结构、环结构或芳香族结构如何影响所评价烃体系的预测粘温行为。这些结果建立了一个实用的框架，用于预测所代表的化学领域内的粘度和密度，并说明了其筛选有机混合物配方的潜力。

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引用次数: 0

Asymptotic models for photochemical reactions in a simple integrating cylinder 简单积分圆柱体中光化学反应的渐近模型

IF 4.7 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-10-13 DOI: 10.1016/j.ces.2026.125344

AbdelAziz Hamza, Necip B. Üner

Photochemical reactions and reactors are often difficult to characterize due to a rich interplay of chemical kinetics with radiation and species transport. Because of this complexity, extracting intrinsic kinetic information, especially with non-collimated lamps, is notoriously difficult, and it is very common to rely on methods of comparative calibration, e.g., actinometry, local measurements of the emissive power of the lamps used, or rigorous computational ray tracing methods. Here, we describe the construction and use of a simple and low-cost cylindrical photochemical chamber that can accommodate various, industrially relevant light sources and spatially integrates radiant flux thanks to a reflective coating applied on its interior walls. By modelling radiation transport at two asymptotic limits, specifically for strongly- and weakly absorbing reaction media, we show that the proposed integrating cylinder can be used with absolute calibration with the help of a macroscopic photon balance. For stagnant reagents and products, one asymptotic case reduces into shrinking core-like reaction when the solutions are opaque, while the other represents a gradientless reaction for dilute solutions. Models reduce to simple mathematical expressions at both limits, whose practical uses are illustrated by two example reactions with different irradiation windows, pyridine photolysis and methylene blue photobleaching. We show that when lamps are well-characterized in terms of their total emissive power, the integrating nature of the chamber allows quantum yield and/or kinetic parameters to be deduced without any additional fitting parameters. The approach presented here provides a flexible platform for studying photochemical conversion in homogeneous liquid-phase reactions

由于化学动力学与辐射和物质传输的丰富相互作用，光化学反应和反应器通常难以表征。由于这种复杂性，提取固有的动力学信息，特别是对于非准直灯，是出了名的困难，并且非常普遍地依赖于比较校准的方法，例如，光光度测定法，使用的灯的发射功率的局部测量，或严格的计算光线追踪方法。在这里，我们描述了一个简单和低成本的圆柱形光化学室的建造和使用，它可以容纳各种工业相关的光源，并且由于在其内壁上应用了反射涂层，在空间上集成了辐射通量。通过模拟两个渐近极限下的辐射输运，特别是强吸收和弱吸收反应介质，我们表明所提出的积分柱可以在宏观光子平衡的帮助下进行绝对校准。对于停滞的试剂和产物，当溶液不透明时，一种渐近情况减少为收缩核样反应，而另一种情况则代表稀释溶液的无梯度反应。在这两个极限下，模型简化为简单的数学表达式，并通过两个不同辐照窗口的反应例子，吡啶光解和亚甲基蓝光漂白来说明其实际应用。我们表明，当灯在其总发射功率方面具有良好的特征时，腔室的积分性质允许在没有任何额外拟合参数的情况下推导出量子产率和/或动力学参数。本文提出的方法为研究均相液相反应中的光化学转化提供了一个灵活的平台

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引用次数: 0

Analytical and numerical study of mean porosity variations in annular packed beds of spherical pellets 球形球团环形充填床平均孔隙度变化的分析与数值研究

IF 5.1 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-10-13 DOI: 10.1016/j.ces.2026.125334

Pablo Díaz-Ulloa, Rodrigo Unzueta, Iván Cornejo

Annular packed beds are used in pebble-bed nuclear reactors, annular membrane reactors for hydrogen production and annular chromatography columns, yet, unlike the cylindrical geometry, no validated model predicts their mean porosity across a wide range of confinement ratios, and the only available correlation was calibrated from a single experimental point. This study uses rigid-body simulation (RBS) to generate annular packed beds of spherical pellets at 52 confinement ratios between 2.25 and 15, with three independent realizations each and a fixed inner radius-to-particle diameter ratio of 2. The generation procedure is validated against annular experimental data comprising an unadjusted radial porosity profile and an independent mean porosity measurement. The mean porosity oscillates non-monotonically with a decaying amplitude, and the first extremum interval is markedly shorter than the subsequent ones. A layer-stacking analytical framework, previously developed for cylindrical beds, is extended to the annular geometry through circular monolayer, zig-zag monolayer and two-coupled-rows regimes, with the first transition located analytically at a confinement ratio of approximately 2.74. The model reproduces the simulated mean porosity within its domain and explains its largest deviation through a nesting threshold at

2 + \sqrt{3} \approx 3.73

, the annular counterpart of the cylindrical threshold. Beyond this domain, an empirical correlation combining a damped oscillation with a quadratic decay envelope describes the full range with a coefficient of determination of 0.970, against 0.690 for the existing annular correlation. These models provide the mean porosity required by pressure drop and transport models for annular reactors and columns.

环形填充床用于球床核反应堆、用于制氢的环形膜反应器和环形色谱柱，然而，与圆柱形结构不同，没有经过验证的模型可以预测其在大范围约束比下的平均孔隙度，并且唯一可用的相关性是从单个实验点校准的。本研究使用刚体模拟（RBS）生成球形球团的环形填充床，约束比为2.25 ~ 15之间的52个，每个有三个独立的实现，固定的内半径与颗粒直径比为2。生成过程通过环空实验数据进行验证，实验数据包括未经调整的径向孔隙度剖面和独立的平均孔隙度测量值。平均孔隙度呈非单调衰减振荡，且第一个极值区间明显短于其后几个极值区间。先前为圆柱形层开发的层-层分析框架，通过圆形单层、之字形单层和双耦合行结构扩展到环形几何结构，第一次过渡的解析位置约为2.74。该模型在其域内再现了模拟的平均孔隙度，并通过2+3≈3.73的嵌套阈值（圆柱形阈值的环形对应）解释了其最大偏差。在此域之外，结合阻尼振荡和二次衰减包络的经验相关描述了整个范围，其决定系数为0.970，而现有的环形相关为0.690。这些模型提供了压力降和输送模型对环形反应器和塔的平均孔隙度要求。

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引用次数: 0

Shear-driven dynamics of surfactant-laden droplets on rough substrates 粗糙基底上表面活性剂液滴的剪切驱动动力学

IF 4.7 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-09-26 DOI: 10.1016/j.ces.2026.125229

Ninad V. Mhatre, Satish Kumar

The depinning of liquid droplets due to flow of a surrounding immiscible fluid plays a crucial role in applications such as enhanced oil recovery, surface cleaning, and crossflow emulsification. Although surfactants are often present in these systems, the role of Marangoni stresses on droplet depinning by an external flow remains unclear. To address this, we develop a lubrication-theory-based model for a thin Newtonian droplet laden with insoluble surfactant on a substrate with Gaussian-shaped defects which are used to account for the effects of surface roughness. The droplet is surrounded by a surfactant-free immiscible Newtonian fluid in a long, narrow rectangular channel, with flow driven by an applied pressure gradient. Using a precursor-film/disjoining-pressure approach for contact-line motion, we derive nonlinear evolution equations for the droplet thickness and interfacial surfactant concentration, which are solved numerically. The pressure gradient transports surfactant from the receding to the advancing contact line, generating a Marangoni flow opposing the pressure-driven flow. This reduces the net shear force on the droplet, leading to depinning at a higher critical pressure gradient. These findings reveal a previously unexamined regime in which interfacial Marangoni stresses, rather than uniform interfacial-tension reduction, govern the critical flow rate. The results provide a mechanistic basis for using surfactant-concentration gradients as a tunable handle to control droplet motion on rough substrates.

由于周围不混相流体的流动，液滴的脱屑在提高采收率、表面清洁和交叉流乳化等应用中起着至关重要的作用。虽然表面活性剂经常存在于这些体系中，但马兰戈尼应力在液滴由外部流动脱落过程中的作用尚不清楚。为了解决这个问题，我们开发了一个基于润滑理论的模型，用于在具有高斯形状缺陷的基底上装载不溶性表面活性剂的薄牛顿液滴，该缺陷用于解释表面粗糙度的影响。液滴被不含表面活性剂的不混溶牛顿流体包围在狭长的矩形通道中，流动由施加的压力梯度驱动。采用前驱体-膜/分离-压力的接触线运动方法，推导了液滴厚度和界面表面活性剂浓度的非线性演化方程，并进行了数值求解。压力梯度将表面活性剂从后退输送到前进接触线上，产生与压力驱动流动相反的马兰戈尼流动。这减少了液滴的净剪切力，导致在更高的临界压力梯度下脱漆。这些发现揭示了一个以前未被研究过的机制，在这个机制中，控制临界流速的是界面马兰戈尼应力，而不是均匀的界面张力降低。结果为利用表面活性剂浓度梯度作为可调手柄来控制粗糙基底上的液滴运动提供了机理基础。

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引用次数: 0

Silica-based amphiphilic nanofluid for enhanced heavy oil recovery: performance and mechanistic insights 用于提高稠油采收率的硅基两亲性纳米流体：性能和机理见解

IF 4.7 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-06-28 DOI: 10.1016/j.ces.2026.124549

Yu He, Wanfen Pu, Rui Liu, Qingyuan Chen, Hongli Liu, Shitong Jiang, Jingjing Zhong

In the process of chemical viscosity reduction for EOR in heavy oil reservoirs, nanoparticles have demonstrated significant potential due to their unique physicochemical properties. In this study, an amphiphilic nanofluid was synthesized, and its performance was systematically evaluated through interfacial tension (IFT), wettability alteration, emulsification, oil-film detachment, and core flooding experiments. Furthermore, molecular dynamics simulations were conducted to elucidate the microscopic mechanisms responsible for viscosity reduction. The results demonstrated that the nanofluid exhibited outstanding interfacial activity, reducing the IFT from approximately 30 mN/m to 0.5 mN/m and effectively transforming oil-wet rock surfaces to a water-wet state. A stable O/W emulsion was formed, resulting in a viscosity reduction of up to 98% at 80% water cut. Oil-film detachment tests confirmed that the nanofluid completely removed adhered oil films from rock surfaces within 12 h. Core flooding experiments demonstrated that the nanofluid enhanced recovery by 24.75%, representing an additional recovery of 10.83% compared with the surfactant alone. MD simulations revealed strong interactions between the nanofluid and asphaltene molecules, which disrupted asphaltene aggregation and inhibited the formation of large aggregates. Furthermore, the strong confinement effect of the nanofluid on asphaltenes facilitated the formation of stable O/W emulsions, elucidating the molecular mechanism underlying viscosity reduction.

在稠油油藏提高采收率的化学降粘过程中，纳米颗粒以其独特的物理化学性质展现出巨大的应用潜力。本研究合成了一种两亲性纳米流体，并通过界面张力（IFT）、润湿性改变、乳化、油膜剥离和岩心驱油实验对其性能进行了系统评价。此外，还进行了分子动力学模拟，以阐明粘度降低的微观机制。结果表明，纳米流体表现出出色的界面活性，将IFT从大约30 mN/m降低到0.5 mN/m，并有效地将油湿岩石表面转变为水湿状态。形成了稳定的油水乳状液，在含水80%的情况下，粘度降低了98%。油膜剥离试验证实，纳米流体在12 h内完全去除岩石表面粘附的油膜。岩心驱油实验表明，纳米流体的采收率提高了24.75%，与单独使用表面活性剂相比，采收率提高了10.83%。MD模拟显示，纳米流体与沥青质分子之间存在强烈的相互作用，破坏了沥青质聚集，抑制了大聚集体的形成。此外，纳米流体对沥青质的强约束作用有助于形成稳定的油水乳状液，阐明了降低粘度的分子机制。

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引用次数: 0

Discharge of packed particles through side orifice driven by gas pressure above 在上方气体压力的驱动下，堆积颗粒通过侧孔排出

IF 4.3 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-05-15 Epub Date: 2026-02-10 DOI: 10.1016/j.ces.2026.123563

Donghui Liu, Yongdou Wang, Quanhong Zhu

This work aimed to explore the pressure-driven discharging behavior of packed particles through the side orifice. The gas pressure (P) above inventory surface in the hopper was raised by introducing air at a constant rate. A column was assigned above to continuously replenish the discharged particles so that the inventory level in the hopper, P, and q_p (mass discharge rate) could maintain for a long time. Eventually, the influence of P on q_p could be rigorously explored and analyzed. q_p was measured to increase with increasing P or d_o (orifice diameter), both being concave functions. When the distance from the orifice center toward inventory surface in the hopper was fixed, q_p could be well correlated to Q_leak (gas leakage through the orifice) in quadratic form. Thus, the aforementioned increase of q_p with P or d_o could be ascribed to that Q_leak was raised and the particle discharge driven by the gas pressure above differed significantly from the pneumatic conveying. The Beverloo model was proved to be adequate for correlating q_p and d_o at all levels of P (<1.5 kPa). C embedded therein was fitted to be ∼ 0.007 (independent of P). The huge difference from that (∼0.20) drawn for the gravity-driven particle discharge resulted probably from distinct mechanisms for the arch above the orifice to decompose. k decreased from –49 to –159 with P_d increasing from 0.3 kPa to 1.5 kPa, agreeing with the experimental observation that the actual cross-section for the particle discharge was gradually enlarged.

本工作旨在探讨压力驱动下填充颗粒通过侧孔的放电行为。通过以恒定速率引入空气，提高料斗中库存面以上的气体压力(P)。在上面设置了一个柱子，不断补充排出的颗粒，使料斗中的库存水平P和qp（质量排出率）保持较长时间。最终，P对qp的影响可以进行严格的探索和分析。qp随P或do（孔口直径）的增大而增大，两者均为凹函数。当孔口中心到料斗内库存面距离一定时，qp与Qleak（通过孔口的气体泄漏量）可以很好地呈二次型相关。因此，上述qp随P或do的增加可归因于Qleak升高，且上述气体压力驱动的颗粒排出量与气力输送明显不同。Beverloo模型被证明可以很好地将所有P水平（<1.5 kPa）下的qp和do相关联。其中的C值拟合为~ 0.007（与P无关）。与重力驱动颗粒放电的巨大差异（~ 0.20）可能是由于孔口上方拱的分解机制不同。k从-49减小到-159，Pd从0.3 kPa增大到1.5 kPa，与实验观察一致，颗粒放电实际截面逐渐增大。

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引用次数: 0

A Semi-Resolved LBM-DEM Coupling Approach: Methodology, Modeling, and Validation 半分辨LBM-DEM耦合方法：方法论、建模和验证

IF 4.3 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-05-15 Epub Date: 2026-02-10 DOI: 10.1016/j.ces.2026.123562

Yin Zhu, Liming Che, Haiqiang Lin, Bin Wei, Hua Zhou

A semi-resolved Lattice Boltzmann Method − Discrete Element Method (LBM-DEM) coupling approach is proposed to overcome the unphysical velocity oscillations in the transitional regime, where the particle-to-grid size ratio approaches unity. Kernel function approximation is employed to smooth the particle-to-grid mapping, while various drag force models are adopted to describe the particle–fluid interactions. Correspondingly, the governing equations of the modified Immersed Moving Boundary-LBM (IMB-LBM) are adapted to accurately describe the fluid–solid coupling effects. The proposed method was systematically validated through a series of benchmark simulations, including sedimentation of a nylon ball and a steel ball, a fluidized bed, and a spouted bed. Results demonstrate that the proposed semi-resolved framework effectively bridges resolved and unresolved LBM-DEM regimes. Parameter analysis identifies the Energy Minimization Multi-Scale (EMMS) model as the most suitable drag correlation for fluidized beds. Furthermore, background expansion factors of 3–4 optimally balance computational accuracy and efficiency. This work extends the applicability of the LBM-DEM method, providing a robust and unified framework for modeling particle–fluid systems.

提出了一种半分辨晶格玻尔兹曼方法-离散元方法（LBM-DEM）耦合方法，以克服过渡区中粒子与网格尺寸比接近统一的非物理速度振荡。采用核函数近似平滑粒子到网格的映射，采用各种阻力模型来描述粒子与流体的相互作用。相应的，采用了改进的浸入式移动边界- lbm （IMB-LBM）控制方程来准确地描述流固耦合效应。通过一系列的基准模拟，包括尼龙球和钢球的沉降，流化床和喷淋床，系统地验证了所提出的方法。结果表明，所提出的半解析框架有效地连接了解析和未解析的LBM-DEM机制。参数分析表明，能量最小化多尺度（EMMS）模型是最适合流化床的阻力关联模型。背景展开因子为3-4，可达到计算精度和效率的最佳平衡。这项工作扩展了LBM-DEM方法的适用性，为颗粒-流体系统建模提供了一个鲁棒和统一的框架。

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引用次数: 0

Experimental study on intermittent nitrogen injection to eliminate hydrate blockage 间歇式注氮消除水合物堵塞的实验研究

IF 4.3 2区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Science

Pub Date : 2026-05-15 Epub Date: 2026-02-10 DOI: 10.1016/j.ces.2026.123587

Yiwei Wu, Xiaohui Wang, Zhenbin Xu, Liyong Bao, Jiaxuan Du, Zehao Liu, Hongyi Yu, Changyu Sun, Guangjin Chen

Hydrate blockage is a major challenge to the safe and efficient transportation of oil and gas in the pipelines, and preparing hydrate blockage samples in limited-size experimental equipment is a key research difficulty. To address this issue, this study developed a high-pressure filtration method for producing methane hydrate blockage samples. By discharging unreacted gas–liquid and compressing hydrate particles into chunks under constant pressure yields hydrate blockage samples, enabling laboratory simulation of hydrate blockage removal performance. Nitrogen injection experiments were conducted to examine the effect of injection pressure, injection volume of nitrogen, hydrate blockage temperature, and hydrate decomposition water on the decomposition quantity of hydrate blockage. The experimental results show that when the initial injection volume of N₂ maintain constant, for every 1 MPa increase in nitrogen injection pressure, the amount of methane released from hydrate would decrease by 3.93 × 10^-5 mol/cm³. When the injection pressure of N₂ was maintained around 4.20 MPa, for every 1 cm³ increase in nitrogen injection volume, 0.0011 mol of methane will decompose from the hydrate phase. When the ambient temperature increases from 274.15 to 277.05 K, the amount of methane decomposed from hydrate blockage induced by per unit volume of N₂ rises to 0.00206 mol/cm³. The accumulation of hydrate decomposed water would increase mass transfer resistance for methane migration, significantly lowering hydrate decomposition efficiency. When hydrate was fully submerged into the water phase, the dissociation rate of gas hydrate approached to zero, and the hydrate decomposition was completely inhibited.

水合物堵塞是油气管道安全高效输送面临的重大挑战，在有限尺寸的实验设备上制备水合物堵塞样品是一个关键的研究难点。为了解决这一问题，本研究开发了一种高压过滤方法来生产甲烷水合物堵塞样品。通过排出未反应的气液，在恒压下将水合物颗粒压缩成块状，得到水合物堵塞样品，实现水合物堵塞去除性能的实验室模拟。通过注氮实验，考察注氮压力、注氮量、水合物堵塞温度、水合物分解水量对水合物堵塞分解量的影响。实验结果表明，在N2初始注入量一定的情况下，注氮压力每增加1 MPa，水合物甲烷释放量减少3.93 × 10-5 mol/cm3。当氮气注入压力保持在4.20 MPa左右时，氮气注入体积每增加1 cm3，甲烷水合物相分解量为0.0011 mol。当环境温度从274.15 K增加到277.05 K时，单位体积N2诱导水合物堵塞分解甲烷的量增加到0.00206 mol/cm3。水合物分解水的积累会增加甲烷迁移传质阻力，显著降低水合物分解效率。当水合物完全浸入水相时，天然气水合物的解离速率趋近于零，水合物的分解被完全抑制。

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