Chemical Engineering Research & Design最新文献

{"title":"Study on evaluation method of drilling fluid-salt formation interaction based on radial flow equivalence","authors":"Yuan He,&nbsp;Li Kang,&nbsp;Rong Li,&nbsp;Tong Cheng,&nbsp;Fu Li,&nbsp;Bo Yang","doi":"10.1016/j.cherd.2026.01.041","DOIUrl":"10.1016/j.cherd.2026.01.041","url":null,"abstract":"<div><div>During the processes of drilling fluid circulation and cementing operation, the working fluid in the wellbore annulus mainly exhibits axial flow. Traditional large-scale axial flow simulation devices, such as horizontal well drilling fluid sand-carrying devices, can relatively truly reproduce the flow state of working fluid. However, they have problems including large volume, high cost, and inconvenience in operation and maintenance, which result in low utilization rate in conventional experiments. To date, no dedicated device has been developed for the simulation of axial flow by means of radial flow. This study proposes a new method that uses radial flow to simulate axial flow, aiming to evaluate the performance changes of oil and gas field working fluid when it flows through salt formations, as well as the effects of erosion and contamination on salt formations caused by the working fluid. It conducts research on the interaction method with working fluid as the subject and salt formation as the object, deduces the equivalent semi-theoretical formula between radial flow and axial flow under the conditions of shear rate and contact area, and develops a set of simulation experimental devices. The innovation of this study does not lie in the radial flow equivalence principle itself, but in its specific application to the solid-liquid coupling of drilling fluid-salt formation and the full-chain simulation of erosion-dissolution-contamination in salt formations. Taking laboratory experiments as an example, after 120 min of erosion on the salt formation by two drilling fluid systems (DSP and JHJS) optimized through this evaluation method, the variation range of rheological properties and fluid loss performance is 5%–10%, the dissolution depth of the salt formation is tiny, and the surface morphology remains unchanged. This method can provide an operable experimental means for the evaluation of drilling fluid salt resistance and the optimization of drilling formulas for salt formations. It also has guiding significance in practical construction, as it can realize cycle optimization in both deep wells and medium-shallow wells, and provide reliable technical support for the design and on-site application of drilling fluid systems under complex well conditions.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 89-96"},"PeriodicalIF":3.9,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micro-feeding and mixing of pharmaceutical solid dosage forms under external vibration","authors":"Liang Zhang ,&nbsp;Haifeng Lu ,&nbsp;Xiaolei Guo ,&nbsp;Haifeng Liu","doi":"10.1016/j.cherd.2026.01.048","DOIUrl":"10.1016/j.cherd.2026.01.048","url":null,"abstract":"<div><div>This study addresses the challenges of micro-dosing and mixing in the continuous manufacturing of solid pharmaceutical formulations by developing a novel continuous feeding-mixing system based on external vibration excitation. The innovative design of a hopper structure with adjustable outlet area distribution demonstrated the potential for achieving precise mixing control of an active pharmaceutical ingredient (API) and an excipient across varying ratios. Experiments first validated the promotion of viscous particle flow by vertical vibration, achieving stable feeding within the range of 0.6–15 mg/s. Building on this, precise control of mixing ratios was enabled by designing different outlet area ratios. In mixing performance evaluation, online X-ray fluorescence spectroscopy confirmed the system achieves high-uniformity mixing with a coefficient of variation below 10 %. The study further revealed that optimal mixing stability occurs when Γ &lt; 5, whereas excessive vibration degrades mixing quality.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 97-105"},"PeriodicalIF":3.9,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PdO-sensitized MoO3/SiO2 S-scheme heterojunction as a highly efficient and reusable photocatalyst for visible-light driven Hg(II) remediation","authors":"Abeer A. Rajhi ,&nbsp;Amal S. Basaleh ,&nbsp;Naif S. Aljohani ,&nbsp;Ahmed Shawky ,&nbsp;Mostafa E. Salem ,&nbsp;Reda M. Mohamed","doi":"10.1016/j.cherd.2026.01.047","DOIUrl":"10.1016/j.cherd.2026.01.047","url":null,"abstract":"<div><div>The progress of highly efficient and robust photocatalysts is essential for addressing the global challenge of heavy metal water contamination. In this work, a novel ternary nanocomposite was constructed by impregnating trace amounts of palladium(II) oxide (PdO) nanoparticles onto a silica-supported molybdenum trioxide (MoO₃/SiO₂) framework via a facile sol-gel method. The resulting PdO/MoO₃/SiO₂ heterostructures were thoroughly characterized to improve their photocatalytic performance. The heterostructure with an optimal loading of 4.0 wt% PdO verified superior properties, including relatively higher specific surface area of 150.19 m²g^–1, a significantly lessened optical bandgap of 2.11 eV, and distinctly improved charge carrier separation. Under visible-light exposure, this adjusted photocatalyst displayed outstanding activity, achieving the complete photoreduction of aqueous Hg(II) ions in an faster timeframe of 45 min. The reaction tracked pseudo-first-order kinetics, with a high initial rate of 29.06 µM min^–1. The catalyst also exhibits extraordinary stability, preserving 96 % of its initial efficiency after five recycles. These findings indicate the PdO/MoO₃/SiO₂ nanocomposite as a capable, high-performance photocatalyst for real application in environmental remediation.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 120-129"},"PeriodicalIF":3.9,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Competitive exchange model of aluminium ions and rare earth ions in the leaching of ion-adsorption type rare earth ores","authors":"Ying Huang ,&nbsp;Sihai Luo ,&nbsp;Bengen Hong ,&nbsp;Yanliang Wang ,&nbsp;Ping Long","doi":"10.1016/j.cherd.2026.01.037","DOIUrl":"10.1016/j.cherd.2026.01.037","url":null,"abstract":"<div><div>Aluminium ions (Al³⁺) substantially influence the leaching of rare earth ions (REs). A competitive exchange model between Al³ ⁺ and REs was established to present a rational source-sink term for simulating the leaching process of ion-adsorption type rare earth ores. In this study, the yttrium ions (Y^3 +) were used to represent REs. Isothermal equilibrium ion exchange batch experiments were conducted to investigate the impact of hydrogen ion (H⁺) concentration on the competitive exchange features between Al³ ⁺ and Y³⁺ by using magnesium sulphate solutions at varying pH levels to leach pure yttrium samples, pure aluminium samples and mixed Al-Y samples. The experiments investigated the impact of hydrogen ion (H⁺) concentration on the competitive exchange features between Al³ ⁺ and Y³⁺. The findings demonstrated that H⁺ concentration had an attenuating effect on the initial solid phase concentrations of both Y³⁺ and Al³ ⁺ before exchange. A two-parameter logistic function of H⁺ concentration could describe this attenuation coefficient. Then, integrating the Kerr model, a competitive exchange model for Al³ ⁺ and Y³⁺ was developed. Compared with the experimental data, all the determination coefficients exceeded 0.850, implying that the proposed mathematical model exhibited high accuracy.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 46-53"},"PeriodicalIF":3.9,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of current processes for lithium carbonate production: Determination of key performance indicators","authors":"Juan Ramiro Lezama ,&nbsp;Sofía Micaela Guerrero Soler ,&nbsp;Laura Emilia Giménez ,&nbsp;Eleonora Erdmann","doi":"10.1016/j.cherd.2026.01.044","DOIUrl":"10.1016/j.cherd.2026.01.044","url":null,"abstract":"<div><div>The objective of this study is to conduct a comparative analysis of the two principal technologies for obtaining lithium carbonate currently: evaporative processes versus Direct Lithium Extraction (DLE) based on selective adsorption with resins, to determine the production potential for each of them and the convenience of their implementation in salars. The mass and energy balances of each process are resolved, considering a common calculation base. Aspen Plus is used as a simulation tool to access the thermodynamic data of the chemical species involved. Key Performance Indicators (KPIs) are determined, including brine feed, water consumption, reagents used, and energy consumption per ton of lithium carbonate produced. In turn, the interaction between virgin brine and depleted brine is evaluated. Each method has advantages and disadvantages in terms of these indicators, which must be evaluated for each project. In addition, electrical energy consumption was included to compare the peak power demand between both processes.</div><div>The selection of these processes necessitates an evaluation of environmental, economic, and social factors to guarantee the sustainable advancement of the lithium sector in these areas. A better approach, from the production point of view, optimizing the factors mentioned, is to propose a combined scheme of both technologies.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 106-119"},"PeriodicalIF":3.9,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Attention-based neural network fusion for fouling prediction in Ethylene-Vinyl Acetate heat exchangers","authors":"Yellam Naidu Kottavalasa ,&nbsp;Andrea Battaglia ,&nbsp;Giovanni Bevilacqua ,&nbsp;Gianni Marchetti ,&nbsp;Andrea Salfinger ,&nbsp;Lauro Snidaro","doi":"10.1016/j.cherd.2026.01.043","DOIUrl":"10.1016/j.cherd.2026.01.043","url":null,"abstract":"<div><div>Fouling, a phenomenon in which materials originating from the process fluid settle onto heat-exchange surfaces, significantly reduces thermal efficiency, increases energy consumption, and raises maintenance costs, particularly in high-pressure tubular reactors used for Ethylene-Vinyl Acetate (EVA) polymerization. Accurate, real-time prediction of fouling factor is therefore essential for optimizing operational efficiency, maintaining product quality, and preventing unplanned downtime. This paper proposes a novel attention-based neural network that integrates parallel Bidirectional Gated Recurrent Unit branches with a Multi-Head Attention mechanism to enhance temporal feature extraction and focus on the most informative time steps. In addition to the neural architecture, the framework incorporates Mutual Information-based feature selection stage to retain highly relevant process variables, derived from temperature, pressure, and flow rate measurements collected through sensors across the reactor system. The model was trained on six years of industrial EVA reactor data from Versalis. Experimental results demonstrate that the proposed model consistently outperforms baseline architectures, achieving the lowest test MSE (<span><math><mrow><mn>3</mn><mo>.</mo><mn>48</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></mrow></math></span>), RMSE (<span><math><mrow><mn>4</mn><mo>.</mo><mn>17</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></mrow></math></span>), and highest <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> (0.82) on normalized data. These improvements highlight the model ability to capture complex temporal dependencies and generalize under varying operational conditions. The proposed approach offers a scalable and effective solution for predictive fouling monitoring in polymerization heat exchangers, with potential applicability across other energy-intensive chemical manufacturing processes.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 23-34"},"PeriodicalIF":3.9,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146015854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silver-based deep eutectic solvent for the extraction and separation of 1-octene/n-octane: Insights into the underlying molecular mechanism","authors":"Kang Zhao ,&nbsp;Shasha Zhao ,&nbsp;Zhen Liu","doi":"10.1016/j.cherd.2026.01.042","DOIUrl":"10.1016/j.cherd.2026.01.042","url":null,"abstract":"<div><div>Addressing the core challenge of insufficient selectivity of traditional solvents in the separation of long-chain α-olefins/alkanes (such as 1-octene/n-octane), this study innovatively constructs a silver trifluoromethanesulfonate (AgOTf)/N,N-dimethylformamide (DMF) deep eutectic solvent (DES) system based on the “Ag⁺-DMF” synergistic coordination and hydrogen bonding network mechanism for the extraction and separation of 1-octene/n-octane. Through systematic optimization of process parameters, under conditions of 273 K, an alkane/olefin mass ratio of 2:1, water content of 5 %, HBA:HBD molar ratio of 1:2, and a rotational speed of 200 rpm, the system achieves a remarkable separation selectivity of 27.23 for 1-octene/n-octane. Quantum chemical calculations based on Density Functional Theory (DFT) indicate that 1-octene is specifically captured by AgOTf/DMF through strong Ag⁺-π bonding (binding energy: −45.0 kJ/mol) and OTf^⁻∙∙∙H-C hydrogen bonding. In contrast, n-octane exhibits only weak non-specific interactions with AgOTf/DMF (binding energy: −0.2 kJ/mol), resulting in a binding energy difference of 44.8 kJ/mol, which overcomes the separation bottleneck caused by the similar physicochemical properties of olefins and alkanes. Additionally, the DES demonstrates excellent low-temperature regenerability and cyclic stability, offering a promising new solvent solution for industrial olefin/alkane separation.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"226 ","pages":"Pages 656-666"},"PeriodicalIF":3.9,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A systematic hybrid mechanistic–machine learning framework for catalytic reactor modelling and computational validation using CO oxidation","authors":"Ebenezer Aquisman Asare ,&nbsp;Dickson Abdul-Wahab ,&nbsp;Elsie Effah Kaufmann ,&nbsp;Rafeah Wahi ,&nbsp;Zainab Ngaini ,&nbsp;Abigail Ampadu","doi":"10.1016/j.cherd.2026.01.039","DOIUrl":"10.1016/j.cherd.2026.01.039","url":null,"abstract":"<div><div>Accurately forecasting the fast transients that govern catalytic reactors remains difficult because first-principles ordinary differential equation (ODE) models neglect unmodelled heat and mass-transfer effects and therefore perform poorly (baseline CO-oxidation rate <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> = –0.231). For the above reason, this study presents a systematic hybrid mechanistic machine-learning (ML) framework that couples a physically rigorous CSTR model with data-driven residual learning to close these physics gaps. A six-factor design of experiments generated 500 operating scenarios, and after simulation, quality screening, derivative estimation, and residual/outlier filtering, the residual-learning dataset comprised approximately 33,096 usable samples. Five regressors (XGBoost, LightGBM, SVR, MLP and sparse Gaussian-process regression) were hyperparameter-tuned with Optuna and blended through weight optimisation. Uncertainty was propagated with GP posterior bands and inter-model disagreement. The optimised ensemble lifted test-set accuracy to <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> = 0.755, RMSE = 0.006 <span><math><mrow><mi>mol·</mi><msup><mrow><mi>m</mi></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup><mi>·</mi><msup><mrow><mi>s</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> and MdAPE = 93 % a dramatic recovery over the mechanistic baseline. ±2σ GP bands captured 94 % of unseen points, providing actionable epistemic bounds. Performance deteriorated by only ∼21 % when 5 % Gaussian sensor noise was injected, confirming robustness for on-line use. By modularising experiment design, physics-guided feature engineering, automated model selection, and calibrated uncertainty quantification, this workflow delivers interpretable, real-time-capable surrogate models within the modelled operating envelope, outperforming pure ODE and single-model ML baselines. The protocol is transferable to other catalytic systems and establishes a reproducible path toward uncertainty-aware reactor optimisation and control.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 1-22"},"PeriodicalIF":3.9,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146015801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling kinetics of wollastonite dissolution and carbonate precipitation in multi-ionic brine systems","authors":"Harwin Sandhu,&nbsp;Sangeeta Garg,&nbsp;Shashikant Yadav","doi":"10.1016/j.cherd.2026.01.040","DOIUrl":"10.1016/j.cherd.2026.01.040","url":null,"abstract":"<div><div>Mineral carbonation using slurry-phase wollastonite (CaSiO₃) composed of suspended micron-scale particles represents an effective strategy for permanent CO₂ sequestration, yet the interactions among ionic strength, dissolution–precipitation kinetics, and surface passivation remain poorly constrained. This study presents a mechanistic thermodynamic–kinetic model integrating CO₂ solubility, wollastonite dissolution, and silica and calcium carbonate precipitation in multi-ionic brines (NaCl, MgCl₂, CaCl₂, Na₂SO₄) relevant to deep saline aquifers. CO₂ solubility decreases across all brines due to salting-out, most strongly in Mg²⁺ - and SO₄^2--rich systems, while wollastonite buffering enhances uptake with solubility ratio coefficients up to 1.95. Dissolution rates peak near pH 3–4 but drop by more than 30 % in Mg²⁺ -rich solutions because of competitive adsorption of Mg²⁺ with Ca²⁺ at wollastonite surface sites, which suppresses Ca²⁺ release. In sulfate-rich brines, SO₄^2- primarily regulates Ca²⁺ activity through sulfate complexation and potential gypsum buffering, thereby delaying the onset of CaCO₃ supersaturation and precipitation. Silica precipitation evolves from reaction-controlled polymerization to diffusion-limited growth as passivating layers develop. CaCO₃ precipitation is triggered only at high supersaturation, limited by CO₃^2- transport and diffusional barriers at elevated pH. Ion flux declines by over 95 % once silica layers approach ∼500 nm, corresponding to a sharp reduction in effective diffusivity and permeability due to pore-space occlusion by secondary mineral phases. Interactions between silica layers and co-precipitating minerals, such as carbonates, modulate layer porosity and diffusivity, suggesting that insights from shale reservoirs can refine predictions of passivation and reaction–diffusion transitions in engineered brine systems. The model predicts a progressive decrease in porosity and transport capacity as silica and CaCO₃ layers thicken, providing a quantitative mechanistic link between mineral reprecipitation, evolving transport properties, and the observed transition from reaction-controlled to diffusion-limited carbonation.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"227 ","pages":"Pages 54-76"},"PeriodicalIF":3.9,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation on the motion behavior of boiler bottom slag in heat exchanger with radial pipes","authors":"Yuxiu Zhang ,&nbsp;Xiangang Liu ,&nbsp;Lei Wang ,&nbsp;Bingzheng Song ,&nbsp;Haibo Gao ,&nbsp;Jiaqi Zong ,&nbsp;Yongqi Liu ,&nbsp;Xiaofei Pan ,&nbsp;Yanxia Wang","doi":"10.1016/j.cherd.2026.01.038","DOIUrl":"10.1016/j.cherd.2026.01.038","url":null,"abstract":"<div><div>The motion behavior of boiler bottom slag in a heat exchanger with radial pipes was experimentally investigated to enhance waste heat recovery. The results indicate that increasing rotational speed from 1.5 to 5.5 rpm leads to a steady rise in the repose angle, accompanied by an increase in active zone thickness from 10 mm to 30 mm and a reduction in passive zone thickness from 55 mm to 35 mm. As the filling ratio increases from 8 % to 24 %, both upper and lower repose angles show a moderate upward trend, while the thicknesses of the active and passive zones increase simultaneously. In contrast, raising the number of radial pipes from 0 to 8 enhances boiler bottom slag agitation, resulting in larger repose angles, a thicker active zone from 10 mm to 23 mm, and a thinner passive zone from 58 mm to 46 mm. Pearson correlation analysis reveals that, for the repose angle, rotational speed (<em>r</em> ≈ 0.95) and the number of radial pipes (<em>r</em> ≈ 0.94) are the dominant factors, both far exceeding the influence of filling ratio (<em>r</em> &lt; 0.9). Regarding the zone thicknesses, the number of radial pipes shows the strongest positive correlation with the active zone (<em>r</em> ≈ 0.99) and a corresponding strong negative correlation with the passive zone (<em>r</em> ≈ -0.99), followed by the influence of rotational speed, while the filling ratio again exhibits a secondary role. These findings establish radial pipes as dual-functional elements that simultaneously enhance heat transfer surface and actively modify granular flow, providing quantitative guidelines for optimizing exchanger design.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"226 ","pages":"Pages 561-568"},"PeriodicalIF":3.9,"publicationDate":"2026-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}