Current Opinion in Chemical Engineering最新文献

We review recent advances in software platforms for model-based design (MBD) organized in five overarching themes — from (1) simulation to optimization, (2) commercial to open-source, (3) process-centric to multiscale, (4) mechanistic to data-driven, and (5) deterministic to uncertain — illustrated with several recent examples in membrane system design. We posit MBD provides (chemical) engineers with principled frameworks to tackle global grand challenges such as sustainable energy, clean water, and equitable access to healthcare by integrating knowledge across disciplines. As such, we predict MBD software, which has historically focused on engineered systems, will evolve to interact with models for natural and social systems more holistically. Finally, we emphasize the importance of open-source software development, especially by users who become contributors.

The carbon capture and utilization (CCU) technology is an effective approach to reducing CO₂ emissions. Given the extensive range of existing technologies within the CCU framework, systematic methods for the optimal selection of economical and sustainable CCU pathways are crucial. To address this challenge, superstructure-based process design has emerged as a popular approach. Over the past several years, numerous contributions have been made in this area. This article provides an overview of surrogate models widely used in process synthesis and introduces mathematical methods for superstructure-based CCU process design. Recent advances in superstructure-based CCU process design are discussed across six selected application areas, including multistage separations for CO₂ capture, CO₂ thermochemical conversion, CO₂ electrochemical conversion, bioenergy with CCU, CO₂ transport network design, and energy systems design in CCU.

Balancing the accuracy and efficiency is critical when employing the discrete particle method to simulate particle-fluid systems in industrial reactors. This article systematically reviews the methods for accelerating discrete particle simulation, including the coarse-graining (CG) methods and the multiscale coupling methods, and pinpoints current challenges and difficulties in each category. In this work, the CG methods are classified into the CG Computational Fluid Dynamics (CFD)-DEM (computational fluid dynamics-discrete element method) and the multiphase particle-in-cell method according to their treatment of interparticle collisions, and the multiscale coupling methods are summarized based on spatial and temporal coupling. Despite their preliminary application in simulating industrial reactors, these methods still face challenges related to accuracy and applicability. Recently, machine learning-based simulations have gained great attention and may offer new insights into the acceleration of discrete particle simulation. We hope this article can assist researchers in comprehending the development of accelerating simulation techniques and encourage the exploration of novel models in this field.

In comparison to alternative water electrolysis technologies, polymer electrolyte membrane water electrolysis (PEMWE) has several advantages, such as high-voltage efficiency, pure gas production, short response time, and the capability to operate under high pressure and current density. A thorough comprehension of the multiphase flow characteristics within the porous transport layer (PTL) and flow channels is vital to enhance the efficiency of PEMWE. This paper presents an overview of current knowledge on multiphase flow in PEMWE and relevant modeling methods, highlighting the significance of regulating the microstructure of PTL and distinguishing the effects of multiphase flow in the flow channel from those in PTL. Moreover, to simulate PEMWE accurately, it is crucial to consider comprehensive physical and electrochemical processes and develop dependable closure models.

To address potential disruptions that arise from internal and external sources, chemical processes need to be designed with the capacity to withstand and recover from disturbances — often referred to as resilience. To integrate resilience capabilities into process design and operations, it is imperative to be cognizant of contributing factors and develop, determine, and incorporate quantitative resilience performance indicators. This paper provides a brief review of recent progress in conceptual frameworks and quantitative metrics for analyzing and designing resilience-aware process systems. Furthermore, key research opportunities in the field of process system resilience, namely the challenges in integrating resilience throughout the life cycle and across the spatiotemporal scales of a process system, are discussed.

Chemical accidents resulting from thermal runaway of chemical reactors can have severe consequences, including catastrophic damages to the public, society, property, and environment. Therefore, it is crucial to develop a methodology that can predict the safety status of reactors and eliminate the potential risk of thermal runaway timely. To this end, various thermal runaway criteria have been established to assess the safety status of reactors over the past decades. This opinion article provides a short review of classic criteria applied to distinguish between runaway and nonrunaway states of reactors. Particularly, the significance of divergence criterion in the field of thermal runaway criteria is emphasized. In addition, to illustrate the general application procedures of the divergence criterion, examples of its utilization in three research domains, including process safety assessment, process parameter optimization, and process monitoring and control, are given. In summary, the remaining challenges and future directions in the development of thermal runaway criteria, especially the divergence criterion, are discussed.

Alternative water sources can be applied to water-stressed agricultural sites to satisfy the increasing water demand. The increased costs associated with the treatment of impaired water, distribution/conveyance/storage, and waste management to meet water quality requirements and regulations are the challenges in developing an alternative water-based irrigation system. This study evaluates the economic feasibility of developing nontraditional water for agriculture and identifies strategies to address the challenges by increasing affordability. In the Southwest United States, reuse of filtered disinfected municipal wastewater offers the most cost-effective option followed by desalinated brackish water, treated produced water, and seawater. High costs, energy demand, concentrate disposal, and soil salinity management are the primary challenges in using alternative water for irrigation. Economic feasibility can be enhanced by implementing autonomous, easy-to-operate, renewable energy-powered, decentralized desalination systems. The affordability of developing alternative water for irrigation will increase with reduced treatment and waste disposal costs, depletion of conventional irrigation water supplies, and droughts.

Recent advances in nonthermal plasma (NTP)-enabled processes have yielded remarkable results and progress in the remediation of Per- and polyfluoroalkyl substances (PFAS), especially in the past three to five years. In comparison to typical chemical oxidation and reduction reactions that are conducted in bulk aqueous solutions with specific reactive oxidative or reductive species, the reported NTP-based PFAS degradations occur mainly at the water–bubble/air interface and increasingly in the bubble interiors. Further, the degradations occur simultaneously in the presence of a multitude of oxidative and reductive species, including radical, ion, photon, and hydrated electron species. These aspects have introduced some interesting science in such PFAS degradations. This opinion highlights such examples by both illuminating their salient features and more importantly proposing perspectives with respect to the observed science.

In order to achieve net-zero emissions until 2050, it is of utmost importance to improve the energy efficiency and thereby reduce the greenhouse gas emissions in the chemical industry. As distillation processes are accounting for the majority of all fluid separations, they are an important target for potential improvements. Although other separation technologies might be a favorable alternative, distillation is not generally an energy-intensive technology and advanced distillation process concepts, exploiting heat pumps, thermal coupling, as well as solvent- and membrane-assisted hybrid processes, may enable significant improvements regarding energy efficiency. The current article summarizes recent developments regarding the synthesis and design of energy-efficient distillation processes and points out future needs and directions for developments to foster the systematic evaluation and application of these advanced distillation process concepts.