This article introduces three mixed integer programming (MIP) models to address a network design problem for mixed plastic waste (MPW) supply chains. By tracking waste compositions throughout the supply chain, the models optimize the technologies needed to process MPW. The three models adopt different approaches to preserve composition information in the supply chain. We also remark on how to improve solution times with additional constraints, and how the models can be easily modified to handle larger‐scale problems. The proposed models provide an approach for examining emerging MPW recycling technologies that may be more sensitive to input composition, as well as determining the extent to which advanced sorting is useful.
{"title":"Optimization methods for plastics management supply chain design","authors":"Shuheng Wang, Christos T. Maravelias","doi":"10.1002/aic.18464","DOIUrl":"https://doi.org/10.1002/aic.18464","url":null,"abstract":"This article introduces three mixed integer programming (MIP) models to address a network design problem for mixed plastic waste (MPW) supply chains. By tracking waste compositions throughout the supply chain, the models optimize the technologies needed to process MPW. The three models adopt different approaches to preserve composition information in the supply chain. We also remark on how to improve solution times with additional constraints, and how the models can be easily modified to handle larger‐scale problems. The proposed models provide an approach for examining emerging MPW recycling technologies that may be more sensitive to input composition, as well as determining the extent to which advanced sorting is useful.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140954108","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}
Polymer-based membrane technology holds immense promise for CO2 separation. However, it faces persistent challenges, including the high CO2 pressure-induced plasticization and permeability-selectivity trade-offs, which significantly hinder the development of polymeric membranes. To tackle this issue, we synthesized a novel polyimide 6FDA-DAT:DABA(6FDD) containing triptycene and carboxylic groups. Upon de-carboxylation induced cross-linking, the membrane demonstrated a simultaneous enhancement of gas permeability and selectivity. Specifically, compared to the uncross-linked 6FDD, the 400°C-24 h cross-linked membrane exhibited a remarkable increase in CO2 permeability by 177% (93.1 Barrer) and a significant rise in CO2/CH4 selectivity by 47% (57.5), reaching the CO2/CH4 upper bound. More importantly, the cross-linked membrane displayed vastly improved CO2 plasticization resistance, withstanding up to 42 bar of CO2 feed pressure. The design of decarboxylated cross-linked membranes in this work paves the way for creating high-performing and plasticization-resistant membranes with potential applications in high-pressure CO2 separations.
{"title":"De-carboxylation of cross-linkable triptycene-based polyimides for CO2 separation","authors":"Xiaoyu Wang, Fangxu Fan, Yongchao Sun, Jingfa Zhang, Canghai Ma, Gaohong He","doi":"10.1002/aic.18471","DOIUrl":"https://doi.org/10.1002/aic.18471","url":null,"abstract":"Polymer-based membrane technology holds immense promise for CO<sub>2</sub> separation. However, it faces persistent challenges, including the high CO<sub>2</sub> pressure-induced plasticization and permeability-selectivity trade-offs, which significantly hinder the development of polymeric membranes. To tackle this issue, we synthesized a novel polyimide 6FDA-DAT:DABA(6FDD) containing triptycene and carboxylic groups. Upon de-carboxylation induced cross-linking, the membrane demonstrated a simultaneous enhancement of gas permeability and selectivity. Specifically, compared to the uncross-linked 6FDD, the 400°C-24 h cross-linked membrane exhibited a remarkable increase in CO<sub>2</sub> permeability by 177% (93.1 Barrer) and a significant rise in CO<sub>2</sub>/CH<sub>4</sub> selectivity by 47% (57.5), reaching the CO<sub>2</sub>/CH<sub>4</sub> upper bound. More importantly, the cross-linked membrane displayed vastly improved CO<sub>2</sub> plasticization resistance, withstanding up to 42 bar of CO<sub>2</sub> feed pressure. The design of decarboxylated cross-linked membranes in this work paves the way for creating high-performing and plasticization-resistant membranes with potential applications in high-pressure CO<sub>2</sub> separations.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140942884","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}
Rajeevan Arunthavanathan, Zaman Sajid, Md. Tanjin Amin, Yuhe Tian, Faisal Khan, Efstratios Pistikopoulos
The growth of artificial intelligence (AI) has allowed industries to automate and improve their efficiency in operations. Especially in process industries, AI helps to develop intelligent models and tools to proactively monitor and predict equipment or system failures, minimize downtime, and optimize maintenance schedules. With the advancements in AI and its ability to perform tasks, there is a growing belief that AI may eventually replace humans. However, the absence of human involvement in operations in the process industry raises safety concerns. Therefore, AI should collaborate with humans rather than replace them in processing facility operations. This technology is referred to as intelligence augmentation (IA). This article (i) presents a detailed comparison between AI and IA's potential in process systems, (ii) identifies the feasibility of using AI and IA in process safety, and (iii) identifies the risk associated with the implementation of AI or IA in process industries.
人工智能（AI）的发展使各行各业得以实现自动化并提高运营效率。特别是在流程行业，人工智能有助于开发智能模型和工具，以主动监控和预测设备或系统故障，最大限度地减少停机时间，优化维护计划。随着人工智能及其执行任务能力的进步，越来越多的人认为人工智能最终可能会取代人类。然而，在流程工业中，如果没有人类参与操作，就会引发安全问题。因此，人工智能应与人类合作，而不是取代人类参与加工设施的操作。这种技术被称为智能增强（IA）。本文(i)详细比较了人工智能和 IA 在流程系统中的潜力，(ii)确定了在流程安全中使用人工智能和 IA 的可行性，以及(iii)确定了在流程工业中实施人工智能或 IA 的相关风险。
{"title":"Process safety 4.0: Artificial intelligence or intelligence augmentation for safer process operation?","authors":"Rajeevan Arunthavanathan, Zaman Sajid, Md. Tanjin Amin, Yuhe Tian, Faisal Khan, Efstratios Pistikopoulos","doi":"10.1002/aic.18475","DOIUrl":"10.1002/aic.18475","url":null,"abstract":"<p>The growth of artificial intelligence (AI) has allowed industries to automate and improve their efficiency in operations. Especially in process industries, AI helps to develop intelligent models and tools to proactively monitor and predict equipment or system failures, minimize downtime, and optimize maintenance schedules. With the advancements in AI and its ability to perform tasks, there is a growing belief that AI may eventually replace humans. However, the absence of human involvement in operations in the process industry raises safety concerns. Therefore, AI should collaborate with humans rather than replace them in processing facility operations. This technology is referred to as intelligence augmentation (IA). This article (i) presents a detailed comparison between AI and IA's potential in process systems, (ii) identifies the feasibility of using AI and IA in process safety, and (iii) identifies the risk associated with the implementation of AI or IA in process industries.</p>","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/aic.18475","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140942871","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}
Yuchao Niu, Shaofu Du, Shankun Liang, Lei Sheng, Yingshuang Meng, Wu Xiao, Xuehua Ruan, Gaohong He, Xiaobin Jiang
Confined crystallization can realize controllable nucleation and growth of crystals with targeted morphologies in a restricted region. Here, we achieved confined reactive crystallization within a novel micro columnar jet flow regime constructed by the hollow fiber membrane. The interface of the jet flow corresponds as the restricted region for reactive crystallization, and the large-sized calcium carbonate (CaCO3) crystals aggregates with millimeter length can ordered and self-assembly grow along the boundary of this region. Formation mechanism of the jet flow was systematically investigated by real-time observation and force analysis. The detected detachment-regrowth cycle during the experiments furtherly uncovered the potential for continuous operation. Linear (diameter: 0.12–0.3 mm; length: 1.5–3.1 mm) and lamellar crystals (thickness of 200–300 nm and average area of 0.21 mm2) were obtained by effectively manipulating the diameter and effective length of jet flow.
{"title":"Hollow fiber membrane governed microjet flow regime for confined crystallization of large-sized crystal aggregates","authors":"Yuchao Niu, Shaofu Du, Shankun Liang, Lei Sheng, Yingshuang Meng, Wu Xiao, Xuehua Ruan, Gaohong He, Xiaobin Jiang","doi":"10.1002/aic.18474","DOIUrl":"https://doi.org/10.1002/aic.18474","url":null,"abstract":"Confined crystallization can realize controllable nucleation and growth of crystals with targeted morphologies in a restricted region. Here, we achieved confined reactive crystallization within a novel micro columnar jet flow regime constructed by the hollow fiber membrane. The interface of the jet flow corresponds as the restricted region for reactive crystallization, and the large-sized calcium carbonate (CaCO<sub>3</sub>) crystals aggregates with millimeter length can ordered and self-assembly grow along the boundary of this region. Formation mechanism of the jet flow was systematically investigated by real-time observation and force analysis. The detected detachment-regrowth cycle during the experiments furtherly uncovered the potential for continuous operation. Linear (diameter: 0.12–0.3 mm; length: 1.5–3.1 mm) and lamellar crystals (thickness of 200–300 nm and average area of 0.21 mm<sup>2</sup>) were obtained by effectively manipulating the diameter and effective length of jet flow.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140942895","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}
The performance of the perturbed-chain statistical associating fluid theory-type equations of state (PC-SAFT-type EOSs) is compromised in predicting properties of pure compounds in the critical region. In our previous research, we introduced an improved volume-translated rescaled PC-SAFT EOS (VTR-PC-SAFT EOS) by incorporating a dimensionless distance-function. Such VTR-PC-SAFT EOS is built based on a critical point-based PC-SAFT EOS that can reproduce the critical temperature, critical pressure, and critical molar volume of pure compounds. VTR-PC-SAFT EOS is found to significantly improve the accuracy of phase behavior predictions in both critical and noncritical regions for pure compounds. In this study, we assess the performance of VTR-PC-SAFT EOS in reproducing the critical and noncritical properties of 251 pure compounds, encompassing 20 distinct chemical species. The testing results indicate that, compared to the other three PC-SAFT-type EOSs, the VTR-PC-SAFT EOS can consistently provide more accurate representations of critical and noncritical properties of 251 pure compounds.
扰动链统计关联流体理论型状态方程（PC-SAFT-type EOSs）在预测临界区纯化合物性质方面的性能受到了影响。在之前的研究中，我们通过加入无量纲距离函数，引入了一种改进的体积转换重标定 PC-SAFT 状态方程（VTR-PC-SAFT EOS）。这种 VTR-PC-SAFT EOS 建立在基于临界点的 PC-SAFT EOS 基础上，可以再现纯化合物的临界温度、临界压力和临界摩尔体积。研究发现，VTR-PC-SAFT EOS 能显著提高纯化合物在临界和非临界区域的相行为预测精度。在本研究中，我们评估了 VTR-PC-SAFT EOS 在再现 251 种纯化合物临界和非临界特性方面的性能，其中包括 20 种不同的化学物质。测试结果表明，与其他三种 PC-SAFT 型 EOS 相比，VTR-PC-SAFT EOS 可以持续更准确地表示 251 种纯化合物的临界和非临界性质。
{"title":"Application of volume-translated rescaled perturbed-chain statistical associating fluid theory equation of state to pure compounds using an expansive experimental database","authors":"Jialin Shi, Changxu Wu, Honglai Liu, Huazhou Li","doi":"10.1002/aic.18466","DOIUrl":"https://doi.org/10.1002/aic.18466","url":null,"abstract":"The performance of the perturbed-chain statistical associating fluid theory-type equations of state (PC-SAFT-type EOSs) is compromised in predicting properties of pure compounds in the critical region. In our previous research, we introduced an improved volume-translated rescaled PC-SAFT EOS (VTR-PC-SAFT EOS) by incorporating a dimensionless distance-function. Such VTR-PC-SAFT EOS is built based on a critical point-based PC-SAFT EOS that can reproduce the critical temperature, critical pressure, and critical molar volume of pure compounds. VTR-PC-SAFT EOS is found to significantly improve the accuracy of phase behavior predictions in both critical and noncritical regions for pure compounds. In this study, we assess the performance of VTR-PC-SAFT EOS in reproducing the critical and noncritical properties of 251 pure compounds, encompassing 20 distinct chemical species. The testing results indicate that, compared to the other three PC-SAFT-type EOSs, the VTR-PC-SAFT EOS can consistently provide more accurate representations of critical and noncritical properties of 251 pure compounds.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140942793","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}
Diego G. Oliva, Andre L. M. Nahes, Julia C. Lemos, André L. H. Costa, Miguel J. Bagajewicz
In this article, we extend a previously developed globally optimal enumeration methodology for the synthesis of heat exchanger networks (HENs) to include the basic design of heat exchangers (HEXs). The method addresses together all trade-offs between network structure, energy usage, and the basic design of the HEXs. Without loss of generality, we focus on shell-and-tube HEXs. Unlike previous approaches, such as Pinch Analysis, Metaheuristic methods, or Mathematical Programming, our procedure guarantees global optimality. The procedure is not iterative and does not present any convergence challenges. We enumerate HEN structures using a mixed-integer linear programming method and we use Set Trimming followed by sorting for the HEX design. In addition, because some network structures are incompatible with single shell exchangers, we use multiple shell exchangers in series. The comparison of the results of the proposed approach with solutions obtained using two alternative methods extracted from the literature indicates that considerable cost reductions may be obtained.
在本文中，我们扩展了之前开发的用于热交换器网络（HENs）合成的全局最优枚举法，将热交换器（HEXs）的基本设计也包括在内。该方法可综合解决网络结构、能源使用和热交换器基本设计之间的所有权衡问题。在不失一般性的前提下，我们将重点放在管壳式热交换器上。与以往的方法（如捏合分析法、元启发式方法或数学编程法）不同，我们的程序保证了全局最优性。该程序不需要迭代，也不存在任何收敛难题。我们使用混合整数线性规划方法枚举 HEN 结构，并使用集合修剪法（Set Trimming）和排序法（Sorting）进行 HEX 设计。此外，由于某些网络结构与单壳交换器不兼容，我们采用了多壳串联交换器。将所提方法的结果与从文献中提取的两种替代方法的结果进行比较后发现，可以大大降低成本。
{"title":"Globally optimal simultaneous heat exchanger network synthesis and basic heat exchanger design","authors":"Diego G. Oliva, Andre L. M. Nahes, Julia C. Lemos, André L. H. Costa, Miguel J. Bagajewicz","doi":"10.1002/aic.18450","DOIUrl":"https://doi.org/10.1002/aic.18450","url":null,"abstract":"In this article, we extend a previously developed globally optimal enumeration methodology for the synthesis of heat exchanger networks (HENs) to include the basic design of heat exchangers (HEXs). The method addresses together all trade-offs between network structure, energy usage, and the basic design of the HEXs. Without loss of generality, we focus on shell-and-tube HEXs. Unlike previous approaches, such as Pinch Analysis, Metaheuristic methods, or Mathematical Programming, our procedure guarantees global optimality. The procedure is not iterative and does not present any convergence challenges. We enumerate HEN structures using a mixed-integer linear programming method and we use Set Trimming followed by sorting for the HEX design. In addition, because some network structures are incompatible with single shell exchangers, we use multiple shell exchangers in series. The comparison of the results of the proposed approach with solutions obtained using two alternative methods extracted from the literature indicates that considerable cost reductions may be obtained.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140919994","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}
Fengbo An, Felix Küster, Stefan Guhl, Martin Gräbner, Andreas Richter
Accurate measurement of heterogeneous reaction kinetics in thermogravimetric analysis (TGA) requires accurate estimation of concentration and temperature in the sample. However, this information is difficult to estimate during the measurement, especially at high temperatures and pressures. Computational Fluid Dynamics (CFD) is used to perform a comprehensive analysis of the temperature and species distribution throughout a high-temperature, high-pressure test rig, including temperature and species transport within the probe sample. The temperature and gas concentration within the sample are accurately calculated by CFD, providing a much deeper insight into the local temperature and species distribution. The numerical results show a significant decrease in gas concentration and temperature in the core region of the packed bed, indicating that bed diffusion dominates the overall conversion for the char reaction studied in this article. The re-evaluation based on the model considers the limitations of heat and mass transfer at each measurement point. This forms the basis for a novel, model-driven approach that derives heterogeneous kinetics from TGA measurements with significantly improved accuracy and reliability.
{"title":"Optimizing kinetic evaluation through CFD-based analysis of heat and mass transfer in a high-pressure TGA","authors":"Fengbo An, Felix Küster, Stefan Guhl, Martin Gräbner, Andreas Richter","doi":"10.1002/aic.18473","DOIUrl":"https://doi.org/10.1002/aic.18473","url":null,"abstract":"Accurate measurement of heterogeneous reaction kinetics in thermogravimetric analysis (TGA) requires accurate estimation of concentration and temperature in the sample. However, this information is difficult to estimate during the measurement, especially at high temperatures and pressures. Computational Fluid Dynamics (CFD) is used to perform a comprehensive analysis of the temperature and species distribution throughout a high-temperature, high-pressure test rig, including temperature and species transport within the probe sample. The temperature and gas concentration within the sample are accurately calculated by CFD, providing a much deeper insight into the local temperature and species distribution. The numerical results show a significant decrease in gas concentration and temperature in the core region of the packed bed, indicating that bed diffusion dominates the overall conversion for the char reaction studied in this article. The re-evaluation based on the model considers the limitations of heat and mass transfer at each measurement point. This forms the basis for a novel, model-driven approach that derives heterogeneous kinetics from TGA measurements with significantly improved accuracy and reliability.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140919916","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}
Han Zhang, Wenwen Zhang, Fusheng Liu, Zheng-Hong Luo, Kunqi Gao, Mengshuai Liu
Multifunctional metallo-/ionic-covalent organic polymers (TCTB@Zn-iCOPs) were constructed through one-pot multicomponent reaction in a deep eutectic solvent at room temperature. The structures of various TCTB@Zn-iCOPs were characterized, demonstrating their successful integration of multiple sites and excellent structural stability. Then TCTB@Zn-iCOPs were employed to transform atmospheric CO2 into cyclic carbonates. The results showed that satisfactory product yields were obtained under mild and additive-free conditions, with a high TOF value of 101 h−1; furthermore, the optimized TCTB@Zn-iCOP2 exhibited excellent versatility in catalyzing the cycloaddition reactions between various substituted epoxides and CO2, and its activity did not significantly decrease after being reused for five times. Compared with previously reported nonmetallic iCOPs, the TCTB@Zn-iCOP2 shows significantly improved activity and stability. Finally, DFT calculations were conducted along with a comparison of energy barriers for possible reaction paths, gaining an in-depth understanding of the synergistic catalytic mechanism involving multiple sites.
{"title":"Unveiling the integrated function of metallo-/ionic-covalent organic polymers for boosting atmospheric CO2 conversion","authors":"Han Zhang, Wenwen Zhang, Fusheng Liu, Zheng-Hong Luo, Kunqi Gao, Mengshuai Liu","doi":"10.1002/aic.18488","DOIUrl":"https://doi.org/10.1002/aic.18488","url":null,"abstract":"Multifunctional metallo-/ionic-covalent organic polymers (TCTB@Zn-iCOPs) were constructed through one-pot multicomponent reaction in a deep eutectic solvent at room temperature. The structures of various TCTB@Zn-iCOPs were characterized, demonstrating their successful integration of multiple sites and excellent structural stability. Then TCTB@Zn-iCOPs were employed to transform atmospheric CO<sub>2</sub> into cyclic carbonates. The results showed that satisfactory product yields were obtained under mild and additive-free conditions, with a high TOF value of 101 h<sup>−1</sup>; furthermore, the optimized TCTB@Zn-iCOP<sub>2</sub> exhibited excellent versatility in catalyzing the cycloaddition reactions between various substituted epoxides and CO<sub>2</sub>, and its activity did not significantly decrease after being reused for five times. Compared with previously reported nonmetallic iCOPs, the TCTB@Zn-iCOP<sub>2</sub> shows significantly improved activity and stability. Finally, DFT calculations were conducted along with a comparison of energy barriers for possible reaction paths, gaining an in-depth understanding of the synergistic catalytic mechanism involving multiple sites.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140920007","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}
Bin Xu, Ge Gao, Xiaoyi Gao, Wufeng Jiang, Xiaoshan Li, Cong Luo, Fan Wu, Liqi Zhang
Extensive experimental research and hydrodynamic models have been proposed to guide the design of superior packings. However, most research has concentrated on the effective void (ε − H) of packing while ignoring the ineffective void (ε − H − HL), which causes discrepancies in hydrodynamic performance compared to actual observations. This study evaluated the hydrodynamic performance under diverse conditions considering the liquid holdup (H), pressure drop (ΔP), and gas flooding velocity (uf). A novel approach to hydrodynamic model construction is introduced by incorporating an ineffective void. The results indicate that at a constant hold-up area, liquid flow (L) and viscosity (μ) significantly influence liquid hold up, moderated by the gas velocity in the flooding area. The pressure drop rises as the viscosity, gas flow rate, and liquid flow rate increase. Notably, a considerable pressure drop initiates flooding at the bottom of the absorber. Elevated liquid flow rates and viscosities correlate with higher ineffective void values (HL) in the packing column. At low gas flow rates, the gas flow rate marginally affects HL values. However, after the flooding point was achieved, the values of HL rapidly increased as the gas flow rate increased. Moreover, a linear relationship emerges between the liquid holdup and HL, as evidenced by the consistent variation in the liquid holdup and the F-factor. Utilizing the ineffective void yields a more accurate fit for the experimental data, reducing the average absolute relative deviation to 10.2%, 7.4%, and 10.8%, respectively.
人们提出了大量的实验研究和流体力学模型来指导优良填料的设计。然而，大多数研究都集中在填料的有效空隙（ε - H）上，而忽略了无效空隙（ε - H - HL），导致流体力学性能与实际观测结果不符。本研究考虑了液体滞留（H）、压降（ΔP）和气体淹没速度（uf），评估了不同条件下的流体力学性能。通过加入无效空隙，引入了一种构建流体力学模型的新方法。结果表明，在恒定截留面积下，液体流量（L）和粘度（μ）对液体截留有显著影响，并受淹没区气体速度的影响。压降随着粘度、气体流速和液体流速的增加而上升。值得注意的是，相当大的压力降会在吸收器底部引发淹没。液体流速和粘度的升高与填料柱中较高的无效空隙值 (HL) 有关。在气体流速较低时，气体流速对 HL 值影响不大。然而，在达到淹没点后，随着气体流速的增加，HL 值迅速增加。此外，液体截留率和 HL 之间呈现线性关系，液体截留率和 F 因子的持续变化也证明了这一点。利用无效空隙可以更准确地拟合实验数据，将平均绝对相对偏差分别减小到 10.2%、7.4% 和 10.8%。
{"title":"New insight and experimental study of ineffective void in hydrodynamic performance of countercurrent-flow packing column","authors":"Bin Xu, Ge Gao, Xiaoyi Gao, Wufeng Jiang, Xiaoshan Li, Cong Luo, Fan Wu, Liqi Zhang","doi":"10.1002/aic.18467","DOIUrl":"https://doi.org/10.1002/aic.18467","url":null,"abstract":"Extensive experimental research and hydrodynamic models have been proposed to guide the design of superior packings. However, most research has concentrated on the effective void (<i>ε</i> − <i>H</i>) of packing while ignoring the ineffective void (<i>ε</i> − <i>H</i> − <i>H</i><sub>L</sub>), which causes discrepancies in hydrodynamic performance compared to actual observations. This study evaluated the hydrodynamic performance under diverse conditions considering the liquid holdup (<i>H</i>), pressure drop (Δ<i>P</i>), and gas flooding velocity (<i>u</i><sub>f</sub>). A novel approach to hydrodynamic model construction is introduced by incorporating an ineffective void. The results indicate that at a constant hold-up area, liquid flow (<i>L</i>) and viscosity (<i>μ</i>) significantly influence liquid hold up, moderated by the gas velocity in the flooding area. The pressure drop rises as the viscosity, gas flow rate, and liquid flow rate increase. Notably, a considerable pressure drop initiates flooding at the bottom of the absorber. Elevated liquid flow rates and viscosities correlate with higher ineffective void values (<i>H</i><sub>L</sub>) in the packing column. At low gas flow rates, the gas flow rate marginally affects <i>H</i><sub>L</sub> values. However, after the flooding point was achieved, the values of <i>H</i><sub>L</sub> rapidly increased as the gas flow rate increased. Moreover, a linear relationship emerges between the liquid holdup and <i>H</i><sub>L</sub>, as evidenced by the consistent variation in the liquid holdup and the <i>F</i>-factor. Utilizing the ineffective void yields a more accurate fit for the experimental data, reducing the average absolute relative deviation to 10.2%, 7.4%, and 10.8%, respectively.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140907561","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}
Industrial chemical processes require sulfur‐resistant catalysts, which reduce catalyst replacement costs and simplify process operations. Herein, a high‐entropy‐stabilized strategy was put forward for sulfur‐resistant catalysis. A spinel high entropy (Zn0.2Mg0.2Cu0.2Mn0.2Co0.2Al2O4) was introduced by ball milling process with aluminum isopropoxide as the main precursor. Zn0.2Mg0.2Cu0.2Mn0.2Co0.2Al2O4 possessed a high surface area of 171.2 m2 g−1, higher than typical high‐entropy oxides (HEOs). The high‐entropy spinel catalyst exhibited better SO2‐resistance performance in the oxidation of carbon monoxide, better than the simple oxides. The SO2‐resistance of Zn0.2Mg0.2Cu0.2Mn0.2Co0.2Al2O4 was primarily improved by reinforcing the stability of the oxide using a high‐entropy structure to decrease the absorption of SO2 on its surface. Any adsorbed SO2 on the surface of the HEO was then selectively trapped by sacrificial metal ions with stronger electron‐withdrawing ability, protecting the active center (Cu2+, Co2+) from poisoning. This work reveals the significance of high‐entropy structures in sulfur resistance.
{"title":"Enhancing sulfur resistance of oxides in carbon monoxide oxidation by a high‐entropy‐stabilized strategy","authors":"Shengyu Du, Pengfei Zhang","doi":"10.1002/aic.18470","DOIUrl":"https://doi.org/10.1002/aic.18470","url":null,"abstract":"Industrial chemical processes require sulfur‐resistant catalysts, which reduce catalyst replacement costs and simplify process operations. Herein, a high‐entropy‐stabilized strategy was put forward for sulfur‐resistant catalysis. A spinel high entropy (Zn<jats:sub>0.2</jats:sub>Mg<jats:sub>0.2</jats:sub>Cu<jats:sub>0.2</jats:sub>Mn<jats:sub>0.2</jats:sub>Co<jats:sub>0.2</jats:sub>Al<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub>) was introduced by ball milling process with aluminum isopropoxide as the main precursor. Zn<jats:sub>0.2</jats:sub>Mg<jats:sub>0.2</jats:sub>Cu<jats:sub>0.2</jats:sub>Mn<jats:sub>0.2</jats:sub>Co<jats:sub>0.2</jats:sub>Al<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> possessed a high surface area of 171.2 m<jats:sup>2</jats:sup> g<jats:sup>−1</jats:sup>, higher than typical high‐entropy oxides (HEOs). The high‐entropy spinel catalyst exhibited better SO<jats:sub>2</jats:sub>‐resistance performance in the oxidation of carbon monoxide, better than the simple oxides. The SO<jats:sub>2</jats:sub>‐resistance of Zn<jats:sub>0.2</jats:sub>Mg<jats:sub>0.2</jats:sub>Cu<jats:sub>0.2</jats:sub>Mn<jats:sub>0.2</jats:sub>Co<jats:sub>0.2</jats:sub>Al<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> was primarily improved by reinforcing the stability of the oxide using a high‐entropy structure to decrease the absorption of SO<jats:sub>2</jats:sub> on its surface. Any adsorbed SO<jats:sub>2</jats:sub> on the surface of the HEO was then selectively trapped by sacrificial metal ions with stronger electron‐withdrawing ability, protecting the active center (Cu<jats:sup>2+</jats:sup>, Co<jats:sup>2+</jats:sup>) from poisoning. This work reveals the significance of high‐entropy structures in sulfur resistance.","PeriodicalId":120,"journal":{"name":"AIChE Journal","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140890009","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}
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