Chemical Engineering Research & Design最新文献

Data-free stealing attack and defense strategy for industrial fault diagnosis system

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-27 DOI: 10.1016/j.cherd.2025.02.031

Tianyuan Jia, Ying Tian, Zhong Yin, Wei Zhang, Zhanquan Sun

In modern industry, data-driven fault diagnosis models have been widely applied, which greatly ensures the safety of the system. However, these data-driven fault diagnosis models are vulnerable to adversarial attacks, where small perturbations on samples can lead to incorrect prediction results. To ensure the security of fault diagnosis systems, it is necessary to design adversarial attack models and corresponding defense strategies, and apply them to the fault diagnosis system. Considering that the training data and internal structure of the fault diagnosis model are not available to the attacker, this paper designs a data-free model stealing attack strategy. Specifically, the strategy generates training data by designing a data generator and uses knowledge distillation to train an substitute model to the attacked model. Then, the output of the substitute model guides the update of the generator. By iteratively training the generator and the substitute model, a satisfactory substitute model is obtained. Next, a white-box attack method is used to attack the substitute model and generate adversarial samples, achieving black-box attacks on the model to be attacked. To counter this data-free stealing attack, this paper proposes a corresponding adversarial training defense strategy, which utilizes the original model to generate adversarial samples for adversarial training. The effectiveness of the proposed attack strategy and defense method is validated through experiments on the Tennessee Eastman process dataset. This research contributes several insights into securing machine learning within fault diagnosis systems, ensuring robust fault diagnosis in industrial processes.

{"title":"Data-free stealing attack and defense strategy for industrial fault diagnosis system","authors":"Tianyuan Jia, Ying Tian, Zhong Yin, Wei Zhang, Zhanquan Sun","doi":"10.1016/j.cherd.2025.02.031","DOIUrl":"10.1016/j.cherd.2025.02.031","url":null,"abstract":"<div><div>In modern industry, data-driven fault diagnosis models have been widely applied, which greatly ensures the safety of the system. However, these data-driven fault diagnosis models are vulnerable to adversarial attacks, where small perturbations on samples can lead to incorrect prediction results. To ensure the security of fault diagnosis systems, it is necessary to design adversarial attack models and corresponding defense strategies, and apply them to the fault diagnosis system. Considering that the training data and internal structure of the fault diagnosis model are not available to the attacker, this paper designs a data-free model stealing attack strategy. Specifically, the strategy generates training data by designing a data generator and uses knowledge distillation to train an substitute model to the attacked model. Then, the output of the substitute model guides the update of the generator. By iteratively training the generator and the substitute model, a satisfactory substitute model is obtained. Next, a white-box attack method is used to attack the substitute model and generate adversarial samples, achieving black-box attacks on the model to be attacked. To counter this data-free stealing attack, this paper proposes a corresponding adversarial training defense strategy, which utilizes the original model to generate adversarial samples for adversarial training. The effectiveness of the proposed attack strategy and defense method is validated through experiments on the Tennessee Eastman process dataset. This research contributes several insights into securing machine learning within fault diagnosis systems, ensuring robust fault diagnosis in industrial processes.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 200-215"},"PeriodicalIF":3.7,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143551786","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}

引用次数: 0

Antibacterial effect of ethyl-methylimidazolium-based ionic liquids anions on forward osmosis membranes

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-27 DOI: 10.1016/j.cherd.2025.02.035

Megawati Zunita , Budiman Batara , Graecia Lugito , I. Gede Wenten , Katja Loos , Sun Theo Constan Lotebulo Ndruru

Ionic liquids (ILs) have emerged as promising materials in various sectors, particularly for enhancing membrane separation and antibacterial performance in water and wastewater treatment applications. This study investigates the antibacterial effects of ethyl methylimidazolium ([EMIM]⁺)-based IL anions on forward osmosis (FO) membranes. Imidazolium-based IL cations were synthesized using a microwave method and grafted onto a thin-film composite (TFC) membrane to improve bacterial inhibition and separation performance. A novel approach utilizing ultrasound methods was employed to integrate polyamide (PA) and ILs onto the polysulfone (Psf) membrane surface. Among the tested ILs, [EMIM][NTf₂] demonstrated the highest antibacterial activity against Escherichia coli, as evidenced by agar disk diffusion and total plate count (TPC) measurements. The Psf-PA-[EMIM][NTf₂] membrane significantly outperformed other membranes in antibacterial activity and exhibited excellent FO membrane performance. The results indicate that incorporating ILs into FO membranes enhances hydrophilicity and antibacterial properties, making them highly suitable for water and wastewater treatment. This study provides valuable insights into developing dual-functional membranes with improved antibacterial and separation performance, contributing to more effective and sustainable treatment technologies.

{"title":"Antibacterial effect of ethyl-methylimidazolium-based ionic liquids anions on forward osmosis membranes","authors":"Megawati Zunita , Budiman Batara , Graecia Lugito , I. Gede Wenten , Katja Loos , Sun Theo Constan Lotebulo Ndruru","doi":"10.1016/j.cherd.2025.02.035","DOIUrl":"10.1016/j.cherd.2025.02.035","url":null,"abstract":"<div><div>Ionic liquids (ILs) have emerged as promising materials in various sectors, particularly for enhancing membrane separation and antibacterial performance in water and wastewater treatment applications. This study investigates the antibacterial effects of ethyl methylimidazolium ([EMIM]<sup>+</sup>)-based IL anions on forward osmosis (FO) membranes. Imidazolium-based IL cations were synthesized using a microwave method and grafted onto a thin-film composite (TFC) membrane to improve bacterial inhibition and separation performance. A novel approach utilizing ultrasound methods was employed to integrate polyamide (PA) and ILs onto the polysulfone (Psf) membrane surface. Among the tested ILs, [EMIM][NTf<sub>2</sub>] demonstrated the highest antibacterial activity against <em>Escherichia coli</em>, as evidenced by agar disk diffusion and total plate count (TPC) measurements. The Psf-PA-[EMIM][NTf<sub>2</sub>] membrane significantly outperformed other membranes in antibacterial activity and exhibited excellent FO membrane performance. The results indicate that incorporating ILs into FO membranes enhances hydrophilicity and antibacterial properties, making them highly suitable for water and wastewater treatment. This study provides valuable insights into developing dual-functional membranes with improved antibacterial and separation performance, contributing to more effective and sustainable treatment technologies.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 149-159"},"PeriodicalIF":3.7,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527021","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}

引用次数: 0

Effects of inlet water flow and potential aggregate breakage on the change of turbid particle size distribution during coagulation-sedimentation-filtration (CSF): Pilot-scale experimental and CFD-aided studies

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-27 DOI: 10.1016/j.cherd.2025.02.033

Dan Xiao , Jun Nan , Weipeng He , Xiaoyue Zhang , Yaqian Fan , Xianzeng Lin

Considering the limitations of using treated water turbidity as the primary water-quality indicator in water treatment plants, pilot-scale experiments and Computational Fluid Dynamics (CFD) simulations were conducted to examine how inlet flow rate and potential shear-induced aggregate breakage affected the evolution of coagulated turbid particles and overall performance of coagulation-sedimentation-filtration (CSF). With increasing flow rates (5–8 m³/h), settled water turbidity and total particle number both increased, with the highest rate (8 m³/h) reducing the removal efficiency of larger-sized turbid particles (> 15 μm) after sedimentation. Although sand filtration achieved about 99 % turbidity and 97 % particle removal efficiency at all flow rates, higher flow rates caused severe filter clogging. Regarding the influence of mixing speed, settled water turbidity and total particle number first increased and then decreased (with the peaks at 51 rpm), and a certain degree of shear-induced breakage appeared to improve the removal percentage of UV₂₅₄ after sedimentation and reduce the head loss rise in sand filtration process. Moreover, CFD-based discussion highlighted that higher inlet flow rates intensified particle mixing and collisions in the flocculation tank, while excessive mixing speeds increased local shear forces and energy consumption near the impeller, worsening filter clogging during filtration.

{"title":"Effects of inlet water flow and potential aggregate breakage on the change of turbid particle size distribution during coagulation-sedimentation-filtration (CSF): Pilot-scale experimental and CFD-aided studies","authors":"Dan Xiao , Jun Nan , Weipeng He , Xiaoyue Zhang , Yaqian Fan , Xianzeng Lin","doi":"10.1016/j.cherd.2025.02.033","DOIUrl":"10.1016/j.cherd.2025.02.033","url":null,"abstract":"<div><div>Considering the limitations of using treated water turbidity as the primary water-quality indicator in water treatment plants, pilot-scale experiments and Computational Fluid Dynamics (CFD) simulations were conducted to examine how inlet flow rate and potential shear-induced aggregate breakage affected the evolution of coagulated turbid particles and overall performance of coagulation-sedimentation-filtration (CSF). With increasing flow rates (5–8 m<sup>3</sup>/h), settled water turbidity and total particle number both increased, with the highest rate (8 m<sup>3</sup>/h) reducing the removal efficiency of larger-sized turbid particles (> 15 μm) after sedimentation. Although sand filtration achieved about 99 % turbidity and 97 % particle removal efficiency at all flow rates, higher flow rates caused severe filter clogging. Regarding the influence of mixing speed, settled water turbidity and total particle number first increased and then decreased (with the peaks at 51 rpm), and a certain degree of shear-induced breakage appeared to improve the removal percentage of UV<sub>254</sub> after sedimentation and reduce the head loss rise in sand filtration process. Moreover, CFD-based discussion highlighted that higher inlet flow rates intensified particle mixing and collisions in the flocculation tank, while excessive mixing speeds increased local shear forces and energy consumption near the impeller, worsening filter clogging during filtration.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 135-148"},"PeriodicalIF":3.7,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527023","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}

引用次数: 0

An experimental study of the mixing characteristics of viscoplastic fluids in dual-impeller agitation systems

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-26 DOI: 10.1016/j.cherd.2025.02.032

Andrew W. Russell , Patrick M. Piccione , Paul F. Luckham , Konstantin S. Pervunin , Christos N. Markides

We study experimentally the agitation of viscoplastic Carbopol™ 980 (C980) fluids in a 2.5-L vertical unbaffled cylindrical vessel using central dual-impeller stirring systems, examining the mixing characteristics of different combinations of standard six-blade Rushton turbines (RTs) and downward-pumping 45°-pitched four-blade turbines (PBTs) of identical diameter D = 41 mm. We consider the effects of rotational speed (as expressed by the modified power-law Reynolds number, Re_m), impeller separation (G/D = 0.73 and 1.22) and a variety of arrangements of the rotors on the mixing characteristics of these systems. Phenomena of cavern segregation and internal flow compartmentalisation are revealed and explained in terms of expected flow patterns. Dual-RT stirrers are found to produce highly symmetrical flow patterns, influenced by the impeller separation, along with strong time-dependent compartmentalisation between the internal flows of both caverns. This flow compartmentalisation can be, however, avoided in dual-PBT systems due to the downward-pumping nature of this system, which also allows for the achievement of a state of full tank homogeneity through cavern engulfment. Comparing the total equivalent volumes of the caverns, V_c^tot, for the examined dual-impeller systems, the mixing effectiveness, as characterised by the growth of V_c^tot with Re_m, is maximised for the RT-PBT and PBT-RT arrangements with a separation of G/D = 1.22, for which V_c^tot is 70–100 % larger at Re_m = 18.5 compared to the dual-RT and dual-PBT arrangements. Although the RT-PBT arrangement performs well, it does not achieve a homogeneous mixing state of the viscoplastic fluid throughout the entire vessel within a reasonable time. Thus, the most efficient mixing system is that featuring a PBT rotor overlying a RT. The findings demonstrate the significant influence of the selection and geometrical arrangement of dual-impeller systems on the mixing of viscoplastic fluids.

{"title":"An experimental study of the mixing characteristics of viscoplastic fluids in dual-impeller agitation systems","authors":"Andrew W. Russell , Patrick M. Piccione , Paul F. Luckham , Konstantin S. Pervunin , Christos N. Markides","doi":"10.1016/j.cherd.2025.02.032","DOIUrl":"10.1016/j.cherd.2025.02.032","url":null,"abstract":"<div><div>We study experimentally the agitation of viscoplastic Carbopol™ 980 (C980) fluids in a 2.5-L vertical unbaffled cylindrical vessel using central dual-impeller stirring systems, examining the mixing characteristics of different combinations of standard six-blade Rushton turbines (RTs) and downward-pumping 45°-pitched four-blade turbines (PBTs) of identical diameter <em>D</em> = 41 mm. We consider the effects of rotational speed (as expressed by the modified power-law Reynolds number, Re<sub>m</sub>), impeller separation (<em>G</em>/<em>D</em> = 0.73 and 1.22) and a variety of arrangements of the rotors on the mixing characteristics of these systems. Phenomena of cavern segregation and internal flow compartmentalisation are revealed and explained in terms of expected flow patterns. Dual-RT stirrers are found to produce highly symmetrical flow patterns, influenced by the impeller separation, along with strong time-dependent compartmentalisation between the internal flows of both caverns. This flow compartmentalisation can be, however, avoided in dual-PBT systems due to the downward-pumping nature of this system, which also allows for the achievement of a state of full tank homogeneity through cavern engulfment. Comparing the total equivalent volumes of the caverns, <em>V</em><sub>c</sub><sup>tot</sup>, for the examined dual-impeller systems, the mixing effectiveness, as characterised by the growth of <em>V</em><sub>c</sub><sup>tot</sup> with Re<sub>m</sub>, is maximised for the RT-PBT and PBT-RT arrangements with a separation of <em>G</em>/<em>D</em> = 1.22, for which <em>V</em><sub>c</sub><sup>tot</sup> is 70–100 % larger at Re<sub>m</sub> = 18.5 compared to the dual-RT and dual-PBT arrangements. Although the RT-PBT arrangement performs well, it does not achieve a homogeneous mixing state of the viscoplastic fluid throughout the entire vessel within a reasonable time. Thus, the most efficient mixing system is that featuring a PBT rotor overlying a RT. The findings demonstrate the significant influence of the selection and geometrical arrangement of dual-impeller systems on the mixing of viscoplastic fluids.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 216-229"},"PeriodicalIF":3.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143551787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental study and CFD simulation on the falling film characteristics of viscous fluid outside a vertical tube at very low Reynolds numbers

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-26 DOI: 10.1016/j.cherd.2025.02.034

Yuandian Lin , Guanying Zhang , Zhiyong Yi , Mei Cong , Haitao Shen , Jigang Zhao

The removal of volatiles from polymers is of great importance. In this paper, the falling film outside the vertical tube at very low Reynolds number (Re＜1) is studied by both experimental and simulation methods. Experimental data were used to establish a relationship between film thickness, fluid viscosity, and flow rate at low Reynolds numbers. The CFD simulation showed good agreement with the experimental results. Simulations also explored the residence time distribution density (

E (t)

), showing that higher flow rates or lower fluid viscosities correspond to narrower

E (t)

distributions. The minimal differences in dimensionless residence time distribution density (

E (θ)

) across different inlet flow rates indicate good consistency in the film flow. As fluid viscosity increases,

E (θ)

shifts slightly leftward and broadens, which enhances mass transfer efficiency during devolatilization. Three special-shaped tube models were established, the simulations revealed that the velocity distribution within the liquid films of elliptical and semicircular tubes follows the Nusselt semi-parabolic distribution. Additionally, all three special-shaped tubes can increase the surface renewal frequency of the gas-liquid interface to reduce the coagulation, which provide that the special-shaped tube has a good application prospect in the vertical falling film devolatilization production of high-viscosity and uniform-quality materials.

{"title":"Experimental study and CFD simulation on the falling film characteristics of viscous fluid outside a vertical tube at very low Reynolds numbers","authors":"Yuandian Lin , Guanying Zhang , Zhiyong Yi , Mei Cong , Haitao Shen , Jigang Zhao","doi":"10.1016/j.cherd.2025.02.034","DOIUrl":"10.1016/j.cherd.2025.02.034","url":null,"abstract":"<div><div>The removal of volatiles from polymers is of great importance. In this paper, the falling film outside the vertical tube at very low Reynolds number (<em>Re</em>＜1) is studied by both experimental and simulation methods. Experimental data were used to establish a relationship between film thickness, fluid viscosity, and flow rate at low Reynolds numbers. The CFD simulation showed good agreement with the experimental results. Simulations also explored the residence time distribution density (<span><math><mrow><mi>E</mi><mo>(</mo><mi>t</mi><mo>)</mo></mrow></math></span>), showing that higher flow rates or lower fluid viscosities correspond to narrower <span><math><mrow><mi>E</mi><mo>(</mo><mi>t</mi><mo>)</mo></mrow></math></span> distributions. The minimal differences in dimensionless residence time distribution density (<span><math><mrow><mi>E</mi><mo>(</mo><mi>θ</mi><mo>)</mo></mrow></math></span>) across different inlet flow rates indicate good consistency in the film flow. As fluid viscosity increases, <span><math><mrow><mi>E</mi><mo>(</mo><mi>θ</mi><mo>)</mo></mrow></math></span> shifts slightly leftward and broadens, which enhances mass transfer efficiency during devolatilization. Three special-shaped tube models were established, the simulations revealed that the velocity distribution within the liquid films of elliptical and semicircular tubes follows the Nusselt semi-parabolic distribution. Additionally, all three special-shaped tubes can increase the surface renewal frequency of the gas-liquid interface to reduce the coagulation, which provide that the special-shaped tube has a good application prospect in the vertical falling film devolatilization production of high-viscosity and uniform-quality materials.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 174-185"},"PeriodicalIF":3.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143528889","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}

引用次数: 0

CFD-DEM investigation of fine charged particle coating in fluidized beds

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-25 DOI: 10.1016/j.cherd.2025.02.030

Saman Kazemi, Fatemeh Tashakori-Asfestani, Sina Kheirabadi, Reza Zarghami, Navid Mostoufi

Particle coating is widely employed across various industries, including chemical, pharmaceutical, and food sectors. Different types of equipment, such as fluidized beds, are commonly used for coating both wet and dry particles. Among these methods, dry particle coating utilizes electrostatic forces, where fine particles adhere to the surface of oppositely charged carrier particles. This study focuses on modeling the coating process of fine particles on carrier particles in a quasi-2D fluidized bed using CFD-DEM. The modified van der Waals and modified electrostatic forces were identified as key factors influencing particle cohesion and the successful coating of fine particles on carriers. Additionally, the study examines the effects of inlet gas velocity, carrier particle diameter, charge, and quantity on the coating process. Modeling results showed that as the charge of carrier particles increases, both coating thickness and the number of long-time remained particles on the carrier particles increases. Also, lower fluidization velocities were more suitable for the coating process in fluidized beds, as cohesive forces outweighed the drag force.

{"title":"CFD-DEM investigation of fine charged particle coating in fluidized beds","authors":"Saman Kazemi, Fatemeh Tashakori-Asfestani, Sina Kheirabadi, Reza Zarghami, Navid Mostoufi","doi":"10.1016/j.cherd.2025.02.030","DOIUrl":"10.1016/j.cherd.2025.02.030","url":null,"abstract":"<div><div>Particle coating is widely employed across various industries, including chemical, pharmaceutical, and food sectors. Different types of equipment, such as fluidized beds, are commonly used for coating both wet and dry particles. Among these methods, dry particle coating utilizes electrostatic forces, where fine particles adhere to the surface of oppositely charged carrier particles. This study focuses on modeling the coating process of fine particles on carrier particles in a quasi-2D fluidized bed using CFD-DEM. The modified van der Waals and modified electrostatic forces were identified as key factors influencing particle cohesion and the successful coating of fine particles on carriers. Additionally, the study examines the effects of inlet gas velocity, carrier particle diameter, charge, and quantity on the coating process. Modeling results showed that as the charge of carrier particles increases, both coating thickness and the number of long-time remained particles on the carrier particles increases. Also, lower fluidization velocities were more suitable for the coating process in fluidized beds, as cohesive forces outweighed the drag force.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 160-173"},"PeriodicalIF":3.7,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143528886","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}

引用次数: 0

Characterization of woody biomass comminution based on entrained flow gasification 基于内流气化技术的木质生物质粉碎特性分析

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-24 DOI: 10.1016/j.cherd.2025.02.026

Hui Zhang , Xiaolei Guo , Shicheng Wang , Haifeng Lu , Haifeng Liu

Efficient dense-phase pneumatic conveying in entrained-flow gasification, processes requires biomass feedstocks to be comminuted to millimeter-scale particles. This study investigates the comminution characteristics of four typical woody biomasses sycamore, metasequoia, birch, and pine using a hammer mill with various screen sizes and moisture contents ranging from 0.5 to 16 wt%. The results reveal that the moisture content significantly effects energy demand and particle size distribution, depending on the biomass composition. For a screen size of 1.0 mm, materials with comparable lignin content (sycamore, metasequoia, and birch) at 0.5 wt% moisture exhibited energy demand and D₉₀ values of 39.4 kWh/t and 605.5 μm, respectively. For higher lignin content (pine), the energy demands and D₉₀ values were 55.1 kWh/t and 732.6 μm. The interplay between moisture and lignin significantly influenced mechanical properties such as bending stress, with pine (>30 % lignin) showing a 61 % reduction in bending stress as moisture increased. Consequently, a predictive model developed to relate energy demand and moisture content achieved a deviation of less than ± 12 %.

{"title":"Characterization of woody biomass comminution based on entrained flow gasification","authors":"Hui Zhang , Xiaolei Guo , Shicheng Wang , Haifeng Lu , Haifeng Liu","doi":"10.1016/j.cherd.2025.02.026","DOIUrl":"10.1016/j.cherd.2025.02.026","url":null,"abstract":"<div><div>Efficient dense-phase pneumatic conveying in entrained-flow gasification, processes requires biomass feedstocks to be comminuted to millimeter-scale particles. This study investigates the comminution characteristics of four typical woody biomasses sycamore, metasequoia, birch, and pine using a hammer mill with various screen sizes and moisture contents ranging from 0.5 to 16 wt%. The results reveal that the moisture content significantly effects energy demand and particle size distribution, depending on the biomass composition. For a screen size of 1.0 mm, materials with comparable lignin content (sycamore, metasequoia, and birch) at 0.5 wt% moisture exhibited energy demand and <em>D</em><sub>90</sub> values of 39.4 kWh/t and 605.5 μm, respectively. For higher lignin content (pine), the energy demands and <em>D</em><sub>90</sub> values were 55.1 kWh/t and 732.6 μm. The interplay between moisture and lignin significantly influenced mechanical properties such as bending stress, with pine (>30 % lignin) showing a 61 % reduction in bending stress as moisture increased. Consequently, a predictive model developed to relate energy demand and moisture content achieved a deviation of less than ± 12 %.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 124-134"},"PeriodicalIF":3.7,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527022","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}

引用次数: 0

Enhancing CO2 capture efficiency in a lab-scale spray tower: An experimental study on flow configurations using potassium carbonate

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-22 DOI: 10.1016/j.cherd.2025.02.020

Ali Najarnezhadmashhadi , Noé Das Neves , Kimberly Yorllet Toala Escobar , Carl Häggmark , Dan Karlsson , Peter Franzén , Christophe Duwig , Henrik Kusar

Spray towers have proven to be efficient in capturing gases and vapours, finding widespread use across various applications including CO₂ capture. As there is scarce reference material regarding spray tower performances with different flow configurations other than the conventional counter-current flow, as well as the use of substitute solvents to MEA, there is a need to study different configurations and setup designs, including different placements of gas and liquid inlets in the absorber tower, to find the optimal configuration. In this study, the capture of CO₂ from a CO₂/N₂ mixture using unpromoted potassium carbonate as the absorbent in a lab-scale spray tower was experimentally measured in four different flow configurations over a wide range of operating conditions, including gas and liquid flow rates, CO₂ concentration, K₂CO₃ concentration and solvent temperature. Among four different configurations, the two sides co-current configuration, with gas nozzles positioned on opposite sides of the column and liquid coming from above, was found to be the most effective setup for enhancing CO₂ capture efficiency by promoting better mixing and contact between gas and liquid.

{"title":"Enhancing CO2 capture efficiency in a lab-scale spray tower: An experimental study on flow configurations using potassium carbonate","authors":"Ali Najarnezhadmashhadi , Noé Das Neves , Kimberly Yorllet Toala Escobar , Carl Häggmark , Dan Karlsson , Peter Franzén , Christophe Duwig , Henrik Kusar","doi":"10.1016/j.cherd.2025.02.020","DOIUrl":"10.1016/j.cherd.2025.02.020","url":null,"abstract":"<div><div>Spray towers have proven to be efficient in capturing gases and vapours, finding widespread use across various applications including CO<sub>2</sub> capture. As there is scarce reference material regarding spray tower performances with different flow configurations other than the conventional counter-current flow, as well as the use of substitute solvents to MEA, there is a need to study different configurations and setup designs, including different placements of gas and liquid inlets in the absorber tower, to find the optimal configuration. In this study, the capture of CO<sub>2</sub> from a CO<sub>2</sub>/N<sub>2</sub> mixture using unpromoted potassium carbonate as the absorbent in a lab-scale spray tower was experimentally measured in four different flow configurations over a wide range of operating conditions, including gas and liquid flow rates, CO<sub>2</sub> concentration, K<sub>2</sub>CO<sub>3</sub> concentration and solvent temperature. Among four different configurations, the two sides co-current configuration, with gas nozzles positioned on opposite sides of the column and liquid coming from above, was found to be the most effective setup for enhancing CO<sub>2</sub> capture efficiency by promoting better mixing and contact between gas and liquid.</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 186-199"},"PeriodicalIF":3.7,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143528890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Control barrier function based dynamic flexibility analysis in infinite time domain for industrial processes

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-22 DOI: 10.1016/j.cherd.2025.02.019

Yuchen Wang , Zuzhen Ji , Chenchen Zhou , Shuang-Hua Yang

Dynamic flexibility analysis is a powerful tool for validating the operational feasibility of dynamic processes under a range of uncertainties, including model parameters and process variables. Furthermore, it indicates the maximum feasible operating space and can be utilized to enhance both process and controller design, which has the potential to be integrated for the purpose of ensuring process operational safety. However, traditional dynamic flexibility analysis relies on discretizing the differential equations of process models, rendering it unfeasible for complex processes or extended time domains. In this article, we propose a formulation of extended dynamic flexibility analysis based on control barrier functions, which is applicable to infinite time domains and capable of validating a set of initial states rather than a single initial point. We also develop a corresponding algorithm for resolution and discuss various methods for simplifying the primal problem to improve computational efficiency. Two case studies are presented to demonstrate the effectiveness of the proposed extended dynamic flexibility analysis, which indicates the maximum feasible region of uncertainties while synthesizing the corresponding safety controller, as well as the feasibility of the resolution procedure.

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引用次数: 0

Separation of ethanol and polyphenols from red wine by diananofiltration

IF 3.7 3区工程技术 Q2 ENGINEERING, CHEMICAL

Chemical Engineering Research & Design

Pub Date : 2025-02-22 DOI: 10.1016/j.cherd.2025.02.023

I. Tsibranska , D. Yankov , M. Dencheva-Zarkova , J. Genova

In the present study NF-based diafiltration runs – single, sequential diaNF/RO process and two- stage diafiltration configurations are investigated in order to check the separation ability towards ethanol and the polyphenolic fraction in red wine Mavrud. Two nanofiltration (Alfa Laval NF99HF, Microdyn Nadir NP030P) and one reverse osmosis (Alfa Laval RO99) membranes are investigated. Due to the high permeate flux and rejection coefficients difference, NF99HF has been most effective for the purposes of moderate wine dealcoholization and high retention of the selected groups of bioactive compounds. From the second step in the sequential diaNF/RO process two outflows with substantially different ethanol content are obtained. Recycling either of them results in a different two-stage diafiltration configuration, whose performance is strongly affected by the number of diavolumes regarding the low-molecular solute; variation of the operation parameters may imply different membrane areas and/or transmembrane pressure in each membrane stage. In the dealcoholization of Mavrud red wine, sequential NF99HF(dia)/RO99 filtration has been successfully used, effectively preserving the bioactive compounds from the group of polyphenols and anthocyanins, as well as the antioxidant activity of the final wine (up to 5 % loss of ORAC activity was measured).

{"title":"Separation of ethanol and polyphenols from red wine by diananofiltration","authors":"I. Tsibranska , D. Yankov , M. Dencheva-Zarkova , J. Genova","doi":"10.1016/j.cherd.2025.02.023","DOIUrl":"10.1016/j.cherd.2025.02.023","url":null,"abstract":"<div><div>In the present study NF-based diafiltration runs – single, sequential diaNF/RO process and two- stage diafiltration configurations are investigated in order to check the separation ability towards ethanol and the polyphenolic fraction in red wine Mavrud. Two nanofiltration (Alfa Laval NF99HF, Microdyn Nadir NP030P) and one reverse osmosis (Alfa Laval RO99) membranes are investigated. Due to the high permeate flux and rejection coefficients difference, NF99HF has been most effective for the purposes of moderate wine dealcoholization and high retention of the selected groups of bioactive compounds. From the second step in the sequential diaNF/RO process two outflows with substantially different ethanol content are obtained. Recycling either of them results in a different two-stage diafiltration configuration, whose performance is strongly affected by the number of diavolumes regarding the low-molecular solute; variation of the operation parameters may imply different membrane areas and/or transmembrane pressure in each membrane stage. In the dealcoholization of Mavrud red wine, sequential NF99HF(dia)/RO99 filtration has been successfully used, effectively preserving the bioactive compounds from the group of polyphenols and anthocyanins, as well as the antioxidant activity of the final wine (up to 5 % loss of ORAC activity was measured).</div></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":"216 ","pages":"Pages 116-123"},"PeriodicalIF":3.7,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520511","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}

引用次数: 0