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Copyright of Automatisierungstechnik is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Management & Quality / Zarządzanie i Jakość is the property of Scientific Society of Organization & Management / Towarzystwo Naukowe Organizacji i Kierownictwa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research new derivatives of pyrroles in good yields were prepared using multicomponent reactions of amoxicillin, activated acetylenic compounds, and alkyl bromides in water as solvent at room temperature in the presence of catalytic amounts of active carbon. The short time of reaction, high yields of product, and easy separation of them are some advantages of this procedure. In this research, the adsorption process was investigated for cefixime and amoxicillin as antibiotic drugs removal using active carbon and zeolite as organic and natural adsorbents in continuous and batch reactors in lab-scale, and the experiments were continued continuously using an adsorbent that absorbed more the two drugs. According to obtained results, the active carbon adsorbed both cefixime and amoxicillin but the zeolite did not adsorb the amoxicillin but adsorbed the high percentage of cefixime in the batch procedure. It can be concluded that some advantages of the continuous process compared to batch reactor are high performance of adsorbent, short time of process, and high percentage of adsorption. Green chemistry is the use of a set of principles to reduce or eliminate the use or generation of unsafe materials in the design, fabrication, and applications of chemical products. Among solvents, water is a green solvent and very suitable for performing organic reaction. The present procedure avoids the use of toxic solvents. According to obtained results, the active carbon adsorbed both cefixime and amoxicillin, but the zeolite did not adsorb the amoxicillin but adsorbed the high percentage of cefixime in the batch procedure. [ABSTRACT FROM AUTHOR]

Product quality is paramount for companies to maintain the trust from their customers. Powder products and in particular fertilizers can suffer damage during storage if the temperature and moisture are not appropriate. Most of the work has focused on drying, but the last stage of cooling is responsible for avoiding product out of specification. A first principles model has been developed for industrial fluidized vibrating cooling units following a multiscale approach, from the particle to the entire unit, to evaluate their operation. The unit consists of two sections using atmospheric and cool air, respectively. A refrigeration cycle is also modelled to compute the needs to cool the air. The unit's model only includes two adjustable parameters, the heat transfer efficiency from the particle to the air as well as for the losses from the unit to atmosphere. The model has been validated using industrial data, resulting in heat flow efficiency from the particle equal to 0.30 and the flow of losses of 1.17 kW/K. The model can reproduce the industrial data within reasonable error and allows predicting the cooling cycle needs and estimating the cost of its operation as a function of the weather. The location of the facility results in the fact that during June-August the atmospheric air cannot cool the product below the critical temperature and the refrigeration cycle needs to operate. • Product features determine the customer acceptance. • An industrial vibrocooling unit has been modelled and validated. • The model is based on first principles with few adjustable parameters. • The model allows predicting the unit operation over a year time. • June-August requires the use of the unit for the product to reach specifications. [ABSTRACT FROM AUTHOR]

In the current research work, electrical resistance tomography (ERT) was employed for monitoring and visualization of crystallization processes. A first-of-its-kind MATLAB-based interactive GUI application "ERT-Vis" is presented. Two case studies involving varied crystallization methods were undertaken. The experiments were designed and performed involving calcium carbonate reactive (precipitative) crystallization for the high conductivity solution-solute media, and the cooling crystallization of sucrose representing the lower conductivity solution–solute combination. The software successfully provided key insights regarding the process in both crystallization systems. It could detect and separate the solid concentration distributions in the low as well as high conductivity solutions using the visual analytics tools provided. The performance and utility of the software were studied using a software evaluation case study involving domain experts. Participant feedback indicated that ERT-Vis software helps by reconstructing images instantaneously, interactively visualizing, and evaluating the output of the crystallization process monitoring data. [ABSTRACT FROM AUTHOR]

• Microscopic modeling of atomic layer etching. • Calculation of reaction rate parameters via first-principles. • Computationally-efficient machine learning model development. • Real-time calculation of optimal operating conditions. With increasing demands for microchips and increasing needs in the nano-scale semiconductor manufacturing industry, atomic layer etching (ALE) has been developing into a critical etching process. Unlike its counterpart in the film deposition domain, atomic layer deposition (ALD), which has been extensively studied, ALE has not been fully studied yet from a modeling and operation point of view. Therefore, this work develops microscopic models to characterize the thermal ALE process of aluminum oxide thin films with two precursors (hydrogen fluoride and trimethylaluminum). First, the reaction mechanisms for the two half-cycles for the thermal ALE process are established. Electronically predicted geometries of the Al 2 O 3 structure with two precursors are optimized. Along with the optimized geometries, possible reaction pathways are proposed and calculated by density functional theory (DFT)-based electronic structure calculations. The proposed reaction paths and their kinetic parameters are used in a kinetic Monte Carlo (kMC) algorithm, which is capable of capturing the features of the thermal ALE of aluminum oxide. The kMC simulation provides an etch time for the given steady-state operating conditions, which are validated via comparison with available experimental results. Finally, data sets collected from the kMC simulation are used to train a feed-forward artificial neural network (FNN) model. The trained FNN model accurately predicts an etch time and dramatically reduces the computation time compared to the kMC simulation, thereby making it possible to carry out real-time, model-based operational parameter calculations. In addition, the trained FNN model can be used to establish a feasible range of operating conditions without demanding experimental work. [ABSTRACT FROM AUTHOR]

Increased globalization, deregulation of energy markets, and environmental constraints, together with associated uncertainty, have created a highly dynamic and uncertain process manufacturing environment. Responding effectively to this increased variation and uncertainty is critical for a company to remain competitive. In this paper, we consider the plant infrastructure in relation to the energy and global market infrastructures. We describe changes to the plant infrastructure system in order to function more effectively in the current manufacturing environment, as well as key research advances that are aligned to addressing challenges faced by present day plant operation. • Discusses relationship between plant, energy, and global market infrastructures. • Identifies challenges associated with the current plant operating environment. • Discusses industry response to identified challenges. • Overview of PSE tools and paradigms aligned with addressing these challenges. • PSE approaches illustrated in the context of industrial air separation plants. [ABSTRACT FROM AUTHOR]

In the current research work, electrical resistance tomography (ERT) was employed for monitoring and visualization of crystallization processes. A first-of-its-kind MATLAB-based interactive GUI application “ERT-Vis” is presented. Two case studies involving varied crystallization methods were undertaken. The experiments were designed and performed involving calcium carbonate reactive (precipitative) crystallization for the high conductivity solution-solute media, and the cooling crystallization of sucrose representing the lower conductivity solution–solute combination. The software successfully provided key insights regarding the process in both crystallization systems. It could detect and separate the solid concentration distributions in the low as well as high conductivity solutions using the visual analytics tools provided. The performance and utility of the software were studied using a software evaluation case study involving domain experts. Participant feedback indicated that ERT-Vis software helps by reconstructing images instantaneously, interactively visualizing, and evaluating the output of the crystallization process monitoring data.

Biomass with a large amount of moisture is well-suited to be processed by supercritical water gasification, SCWG. The precipitation of inorganics, together with char formation and re-polymerization, can cause reactor plugging and stop the process operations. When plugging occurs, sudden injections of relatively large mass quantities take place, influencing the mass flow dynamics significantly in the process. Reactor plugging is a phenomenon very well observed during SCWG of industrial feedstock, which hinders scale-up initiatives, and it is seldom studied with precision in the literature. The present study provides an accurate evaluation of continuous tubular reactor dynamics in the event of sudden injections of water. An interpretation of the results regarding water properties at supercritical conditions contributes to comprehending mass and heat transfer when plugging occurs. Experiments are then compared to SCWG of a biomass sample aiming to give key insights into heat transfer and fluid dynamics mechanisms that could help develop operational and control strategies to increase the reliability of SCWG. In addition, a simplified model is presented to assess the effect of material integrity on burst-event likelihood, which states that SCWG is safe to operate, at 250 bar and 610 °C, in tubular reactors made of 0.22 wall thickness-to-diameter ratio Inconel-625 with superficial microfractures smaller than 30 µm. We also suggest improvement opportunities for the safety of SCWG in continuous operation mode.

To connect theory taught in the classroom and practical skills required for the workforce, a new teaching methodology has been adopted in the Department of Chemical Engineering at the University of Pittsburgh at Johnstown. We have introduced Simtronics, a virtual chemical engineering process simulator, in chemical engineering coursework to teach students how to operate equipment and troubleshoot chemical processes often found in industrial settings. The students then learn the theories and calculations, and how to apply them to the studied processes at varying conditions. The analysis of these varying conditions provides the student with valuable hands‐on experience frequently sought after by employers. [ABSTRACT FROM AUTHOR]

Abstract Nowadays, research on biodiesel focuses on enhancing the conversion and production yield to fulfill the demand. Utilization of new feedstocks, development of highly efficient catalysts, determination of effective and economical reaction approaches, and application of process system engineering tools are efforts for the optimization purposes. This paper reviews the technological progress of reactors used for biodiesel production. The first part gives an overview of previous findings available in the literature. Many factors affecting the production yield of biodiesel have been reviewed such as reaction time, agitator rotational speed, temperature, types of catalyst, catalyst concentration, the molar ratio of oil and alcohol, types of solvent, and types of feedstock. However, the review of different types of reactors used for the biodiesel production is still lacking. The appropriate selection of reactor type is necessary to enhance the product yield and the productivity. Thus, the second part of this paper aims at compiling the information on various reactors. The description of key operating conditions and process design, relevant integrated reaction and separation techniques, recent achievement and progress, and challenges for future development are highlighted. This review provides the basis for exploitation and selection of reactor to enhance optimization, scale-up development, and implementation in industrial-scale biodiesel production. [ABSTRACT FROM AUTHOR]

• 3D CFD simulation of side-fired steam methane reformer was performed. • The numerical simulation was verified with domestic petrochemical plant data. • The effect of burner feed distribution on hydrogen production was studied. Simulation of the steam methane reformer serves as a launching pad to investigate the optimal amount of hydrogen production. In this study, a 3D-CFD simulation is implemented to model transport phenomena for a turbulent fluid flow with chemical reactions within the reformer. Accordingly, the realizable k-ɛ turbulence model and discrete ordinates (DO) radiation model have been employed to simulate the kinetic mechanism of the SMR process and hydrogen/methane combustion. In addition, the REV-scale approach is considered to model the flow in the porous catalyst bed. Numerical results show that 3D-CFD simulation can accurately model such complex flows in comparison to 2D simulation. In the following, 3D numerical simulations have been performed to investigate the effect of fuel distribution between burners on the amount of heat provided, which affects the amount of hydrogen production and the tube wall temperature. Results indicate that the burner feed flow without purge gas and vent gas streams has the highest efficiency in hydrogen production and leads to a ca. 10% increase in hydrogen production compared to industrial case. Although feeding the burner with purge gas and without vent gas increases hydrogen production by about 7% compared to industrial data, it may be a more suitable option due to lower natural gas consumption and economic savings. [ABSTRACT FROM AUTHOR]

Abstract: For distillation columns, a temperature is controlled to hold product quality while the column is operated at constant pressure. In practice, absolute stability of temperature and pressure is unachievable, whereas the product quality, namely, product composition, fluctuates with the variation of them. By analyzing phase equilibrium, the composition fluctuation, caused by slight temperature and pressure variation, cannot be ignored for precise distillation column. Thus, a novel approach is proposed to improve the performance of product quality control. For preliminary, the freestanding pressure dynamic model is established via calculating vapor molar holdup. The modeling method is applied to a commercial ethylene column, and the veracity and reliability of the dynamic model is improved. For principal part, the complementary control strategy is proposed on the basis of the improved dynamic behaviors. Besides qualitative analysis, 2 scenes that contain tight control for external disturbance and transition control for internal regulating are discussed to verify the feasibility and progressiveness of product quality control with complementary structure. [ABSTRACT FROM AUTHOR]

The concept of maintaining or enhancing chemical process safety encompasses a broad set of considerations which stem from management/company culture, operator procedures, and engineering designs, and are meant to prevent incidents at chemical plants. The features of a plant design that take action to prevent incidents on a moment-by-moment basis are the control system and the safety system (i.e., the alarm system, safety instrumented system, and safety relief system). Though the control and safety systems have a common goal in this regard, coordination between them has been minimal. One impediment to such an integrated control-safety system design is that the traditional industrial approach to safety focuses on root causes of incidents and on keeping individual measured variables within recommended ranges, rather than seeking to understand incidents from a more fundamental perspective as the result of the dynamic process state evolving to a value at which consequences to humans and the environment occur. This work reviews the state of the art in control system designs that incorporate explicit safety considerations in the sense that they have constraints designed to prevent the process state from taking values at which incidents can occur and in the sense that they are coordinated with the safety system. The intent of this tutorial is to unify recent developments in this area and to encourage further research by showcasing that the topic, though critical for safe operation of chemical processes particularly as we move to more tightly integrated and economics-focused operating strategies, is in its infancy and that many open questions remain. [ABSTRACT FROM AUTHOR]

Hydrogen is a required key material for petroleum refineries that convert crude oil into products with higher economic value and is often produced by the steam methane reforming (SMR) process, which synthesizes hydrogen and carbon oxides from methane and superheated steam in the presence of a nickel-based catalyst network in a steam methane reformer. To investigate methods for improving profits for a reformer while avoiding costly on-site parametric studies, a high-fidelity model of a steam methane reformer can be investigated. Motivated by this, the present work focuses on developing a computational fluid dynamics (CFD) model of an industrial-scale steam methane reformer that consists of 336 reforming reactors, 96 burners and 8 flue gas tunnels. The motivation for choosing the modeling strategies used in the industrial-scale steam methane reformer CFD model is discussed and is based on expected transport phenomena and chemical reactions within the reformer. Specifically, the finite rate/eddy dissipation turbulence-chemistry interaction model, global kinetic models of hydrogen/methane combustion, global kinetic model of the SMR process and standard k - ∊ turbulence model with the ANSYS Fluent enhanced wall treatment function are used to simulate the formation and consumption rates of all chemical components of the system. In addition, an empirical correlation for estimating the radiative properties of a homogeneous gas mixture, Kirchhoff’s law, Lambert Beer’s law and the discrete ordinate method are employed to simulate radiative heat transfer in the furnace side of an industrial-scale steam methane reformer. Moreover, the modeling strategies of the reforming tubes developed in our previous work are adopted to model 336 reforming tubes in the reformer. Subsequently, the boundary conditions (i.e., the reforming tube feed, burner feed and the energy leakage through the combustion chamber refractory wall) of the industrial-scale reformer CFD model are derived based on typical plant data. The simulation results produced by the industrial-scale reformer CFD model are shown to be in agreement with typical plant data reported in the SMR literature, with the simulation data generated by an industrial-scale reforming tube CFD model and with the simulation data generated by a reforming Gibbs reactor model, which validates the chosen modeling strategies and allows the CFD data to be considered to represent actual plant data with sufficient accuracy for use in industrial operating parameter studies. [ABSTRACT FROM AUTHOR]

It has been repeatedly suggested that the common cause-and-effect approach to evaluating process safety has deficiencies that could be addressed by a systems engineering perspective. A systems approach should consider safety as a system-wide property and thus would be required to integrate all aspects of the process involved with monitoring or manipulating the process dynamics, including the control, alarm, and emergency shut-down systems while operating them independently for redundancy. In this work, we propose initial steps in the first systems safety approach that coordinates the control and safety systems through a common metric (a Safeness Index) and develop a controller formulation that incorporates this index. Specifically, this work presents an economic model predictive control (EMPC) scheme that utilizes a Safeness Index function as a hard constraint to define a safe region of operation termed the safety zone. Under the proposed EMPC design, the closed-loop state of a nonlinear process is guaranteed to enter the safety zone in finite time in the presence of uncertainty while maximizing a stage cost that reflects the economics of the process. Closed-loop stability is established for a nonlinear process under the proposed implementation strategy. [ABSTRACT FROM AUTHOR]

In this work, we introduce a furnace-balancing scheme that generates an optimal furnace-side feed distribution that has the potential to improve the thermal efficiency of a reformer. The furnace-balancing scheme is composed of four major components: data generation, model identification, a model-based furnace-balancing optimizer and a termination checker. Initially, a computational fluid dynamics (CFD) model of an industrial-scale reformer, developed in our previous work, is used for the data generation as the model has been confirmed to simulate the typical transport and chemical reaction phenomena observed during reformer operation, and the CFD simulation data is in good agreement with various sources in literature. Then, we propose a model identification process in which the algorithm is formulated based on the least squares regression method, basic knowledge of radiative heat transfer and the existing furnace-side flow pattern. Subsequently, we propose a model-based furnace-balancing optimizer that is formulated as an optimization problem within which the valve position distribution is the decision variable, and minimizing the sum of the weighted squared deviations of the outer reforming tube wall temperatures from a set-point value for all reforming tubes with a penalty term on the deviation of the valve positions from their fully open positions is the objective function. CFD simulation results provide evidence that the optimized furnace-side feed distribution created by the furnace-balancing scheme can reduce the severity of nonuniformity in the spatial distribution of furnace-side temperature in the combustion chamber even when the reformer is under the influence of common valve-related disturbances. [ABSTRACT FROM AUTHOR]

Dry autothermal reforming is a novel CO 2 utilization process. Thermoneutral points are considered to be the best operating points in autothermal reforming reactors. A theoretical study was done to determine the process thermoneutral points for complete dry autothermal reforming process considering the basic preheater, reactor and condenser configuration. The results were compared to the product yields at reactor thermoneutral points for the same input feed and temperature conditions. The process thermoneutral points were found be better for operational reasons than reactor thermoneutral points. Dry autothermal reforming of methane was used as model example in this study. This study can be used for different autothermal processes to calculate the optimum conditions at which the process can be operated in heat integrated loop without the need of any external thermal energy. [ABSTRACT FROM AUTHOR]

With the integration of computation, networking, and physical process components to seamlessly combine hardware and software resources to improve process efficiency, cybersecurity has become increasingly important for reliable process control, process operation, and supply chain management in the chemical process industries. This paper provides an overview of recent works on cybersecurity issues in the area of process control, process operation and supply chain. We start with an overview of recent cyber-attack detection and mitigation works via machine learning (ML) and model predictive control (MPC) to detect and handle intelligent cyber-attacks. Several most common intelligent cyber-attacks in industrial control systems are first presented, followed by machine learning detection methods and resilient control strategies with encryption–decryption tools to achieve secure communication in the sensor–controller and controller–actuator links. Novel control architectures with inherent robustness to prevent cyber-attacks are then presented. We continue with an overview of cybersecurity issues in process operations and supply chains as well as the interface between information technology and operational technology. Finally, we discuss recent efforts on the interface of cybersecurity and process safety and conclude with a discussion of open issues in this emerging research field. • Overview of cybersecurity issues in industry. • Information technology versus operational technology cybersecurity concerns. • Elaboration on the nature and type of cyberattacks. • Review of research results on cyberattack detection and mitigation. [ABSTRACT FROM AUTHOR]

A novel short-term planning model of the ethylene plant that incorporates the operating variables and energy utilization in both the thermal cracking and the down-stream process is proposed to explore the potential for increasing the production margin and reducing the energy losses. A multi-period mixed-integer nonlinear programming (MINLP) model is formulated to attain the scheduling of parallel furnaces and the energy distribution of the overall plant, along with the determination of the key process operation involving the coil outlet temperature (COT) and coke deposition. The behavior of the product yields and coke formation in terms of varying COT profiles is investigated to enhance the profitability of the whole plant. A real industrial example is investigated to exploit the performance of the proposed model. The results show that the integrated approach attains an improvement in overall profit and achieves significant enhancement in energy savings, compared with the original optimization approach. [ABSTRACT FROM AUTHOR]

Grinding circuit (GC) is the most critical production unit and it also has the highest energy consumption in mineral processing operations. The control and optimization of GC are regarded as important ways to improve product quality and production efficiency of the whole concentration process. The fundamental goal of the automation system of GC is to make the outputs of the controlled processes best follow the control set-points. Moreover, from the standpoint of process engineering, it should as well ensure that the grinding product quality and efficiency during production phase are well controlled within the optimal ranges. Those goals cannot be achieved solely at the level of basic feedback control where global operational indices are not considered. Therefore, higher-level advanced control is required for the whole grinding plant operation to achieve integrated control and optimization of the indices of control, operation and mineralogical economics. This paper overviews the available advanced control methods and technologies for improving operation of GC system based on our experiences of research and practice in this field. A brief introduction of GC and its advanced control problem for process operation are presented first. Then, a comprehensive and systematic review on the available methods and technologies of higher-level grinding advanced control is given. The emphasis of this review is on the approach of data & knowledge based hybrid intelligent advanced feedback control. Issues about the future research on the advanced control of GC are outlined when concluding the paper. [ABSTRACT FROM AUTHOR]