Continuous Process System Research Articles

Hyperparameter Optimization of the Machine Learning Model for Distillation Processes

This study was conducted to enhance the efficiency of chemical process systems and address the limitations of conventional methods through hyperparameter optimization. Chemical processes are inherently continuous and nonlinear, making stable operation challenging. The efficiency of processes often varies significantly with the operator’s level of expertise, as most tasks rely on experience. To move beyond the constraints of traditional simulation approaches, a new machine learning‐based simulation model was developed. This model utilizes a recurrent neural network (RNN) algorithm, which is ideal for analyzing time‐series data from chemical process systems, presenting new possibilities for applications in systems with special chemical reactions or those that are continuous and complex. Hyperparameters were optimized using a grid search method, and optimal results were confirmed when the model was applied to an actual distillation process system. By proposing a methodology that utilizes machine learning for the optimization of chemical process systems, this research contributes to solving new problems that were previously unaddressed. Based on these results, the study demonstrates that a machine learning simulation model can be effectively applied to continuous chemical process systems. This application enables the derivation of unique hyperparameters tailored to the specificities of a limited control volume system.

Strain Optimization of Tensioned Web through Computational Fluid Dynamics in the Roll-to-Roll Drying Process

Unpredictable web temperature distributions in the dryer and strain deviations in the cross-machine (CMD) and machine (MD) directions could hamper the manufacture of smooth functional layers on polymer-based webs through the roll-to-roll (R2R) continuous process system. However, research on this topic is limited. In this study, we developed a structural analysis model using the temperature distribution of the web as a boundary condition to analyze the drying mechanism of the dryer used in an R2R system. Based on the results of this model, we then applied structural modifications to the flow channel and hole density of the aluminum plate of the dryer. The model successfully predicted the temperature and strain distributions of the web inside the dryer in the CMD and MD by forming a tension according to the speed difference of the driven rolls at both ends of the span. Our structural improvements significantly reduced the temperature deviation of the moving web inside the dryer by up to 74% and decreased the strain deviation by up to 46%. The findings can help prevent web unevenness during the drying process of the R2R system, which is essential to minimize the formation of defects on functional layers built over polymer-based webs.

A computational study for the effects of sample movement and cavity geometry in industrial scale continuous microwave systems during heating and thawing processes

Microwave (MW) applications in food processing are used to reduce process time and increase process efficiency. While 915 MHz frequency is dominant for industrial processes, 2450 MHz systems are also observed. Attained temperature uniformity is specific concern with significant effect of the non-uniform electromagnetic field distribution due to the cavity geometry and design. Therefore, the objective of this study was to determine the cavity geometry effect with applied frequency and to present industrial scale continuous process system with a computational approach. A computational model was developed for heating and thawing processes, and experimental validation was completed in a cylindrical MW cavity. Sample rotational movement and cavity geometry effects (conventional rectangular versus cylindrical, ellipsoidal and triangular) were determined, and industrial scale system designs were presented with frequency effect. Temperature change and electromagnetic field distribution were also introduced for improved design. The results demonstrated improved designs for industrial processes.

Microbial safety and shelf‐life of pulsed electric field processed nutritious juices and their potential for commercial production

Pulsed electric field (PEF) processing criteria which could achieve 5 or more log reduction of foodborne pathogens were obtained to get regulatory approval for the commercial production of three unique nutritious juices. Juice samples inoculated with Escherichia coli O157:H7 and Salmonella Typhimurium were processed in a continuous PEF process system. Among 18 tested conditions, three PEF treatments achieved an over 5 log reduction in populations of these pathogens. There was no recovery or regrowth of the pathogens in treated juices during storage at 4, 10, and 22°C. After 24 week-storage, population levels of native microorganisms in treated juices were the same or lower than those of the control samples at Day 0, except for those in apple-honey juice stored at 22°C. PEF processing had no significant effects on °Brix, pH, color, and vitamin C retention. This study provides an important step for the commercialization of PEF application. Novelty impact statement This study was specially designed for the project sponsored by a commercial juice producer. New and unique neutrinos juices were used to establish PEF processing criteria to achieve a 5 log or greater reduction of foodborne pathogens so that all data from this study can be used for regulatory approval and optimum processing conditions obtained from this study will be used for the commercial production of these juice products. This study also provides valuable information to the juice producers with similar nutritious juice products.

Viscosity Variation of Model Compounds during Hydrothermal Liquefaction under Subcritical Conditions of Water

Recent assessments in waste-to-energy technologies highlight hydrothermal liquefaction (HTL) as a suitable process for converting organic-rich waste with high moisture content into a useful resource. Organic waste materials, including sewage sludge, food, and agricultural waste residues, typically contain lipids, carbohydrates, proteins, and lignin with varying compositions depending on their origin. Fluid properties of reacting HTL slurries under subcritical water conditions, particularly viscosity and density, affect material flow and heat transfer in both batch and continuous HTL process systems. Real-time viscosity variations of 20 wt % water slurries of model compounds, sunflower oil, sucrose, and soy protein were determined in a stirred tank batch reactor using the Metzner–Otto method. Measured torque on the impeller shaft at a fixed impeller speed was used to determine the changes in the viscosity of the reacting slurry at different reaction temperatures. Changes in the viscosity of the sunflower oil mixture were insignificant as compared to viscosity variations with sugar- and soy protein-derived feedstock. The viscosity of the soy protein solution decreased rapidly with the temperature during hydrolysis of polypeptides into amino acids between 25 and 100 °C. Further increase in the temperature led to minimal changes in viscosity as more soluble compounds were produced above 100 °C. The viscosity of the sucrose solution changed significantly above 250 °C when carbon compounds precipitated from the solution. Viscosity variations of mixtures of model compounds were determined to predict viscosity changes in biomass.

An Integrated Continuous Flow Micro-Total Ultrafast Process System (μ-TUFPS) for the Synthesis of Celecoxib and Other Cyclooxygenase Inhibitors

Integrated continuous manufacturing has emerged as a promising device for the rapid manufacturing of active pharmaceutical ingredients (APIs). We herein report a newly designed continuous flow micr...

Continuous Fabrication of Wide-Tip Microstructures for Bio-Inspired Dry Adhesives via Tip Inking Process

In this paper, we report a new method for continuous fabrication of dry adhesives composed of microstructures with mushroom-shaped ends. Conventional mushroom microstructure fabrication is performed with a simple molding technique using a reversed phase master. In a typical fabrication process, thin- and wide-tip portions may be ripped during demolding, making it difficult to use in a continuous process. It is also difficult to apply the mushroom structure master to a continuous process system in roll form. Here, a continuous fabrication process was developed by applying the method of fabricating a wide tip using a tip inking method after forming a micropillar. Through the continuous process, the dry adhesive was successfully fabricated and the durability was measured with a reasonable pull-off strength (13 N/cm2). In addition to the reasonable adhesion, high durability is guaranteed, and fabricated dry adhesives are expected to be used in various fields.

Adopting pade approximation for first order plus dead time models for blending process

Dead-time is common to real time processes and occurs when the process variable doesn’t acknowledge to any changes in the set point. Existence of dead time in the systems poses a challenge to control and stabilize, especially in a control feedback loop. Padé approximation provides a determinate approximation of the dead time in the continuous process systems, which can be utilized in the further simulations of equivalent First Order plus Dead Time Models. However, the standard Padé approximation with the same numerator- denominator derivative power, exhibits a jolt at time t=0. This gives an inaccurate approximation of the dead time. To avoid this phenomenon, increasing orders of Padé approximation is applied. In the following manuscript, equivalent First Order plus Dead-Time models of two blending systems of orders four and seven are analysed for the same. As the orders of the Padé approximation increases, the accuracy of the response also increases. The oscillations are increased on a much smaller scale rather than having one big dip in the negative region (as observed in the first few orders of Padé approximation), and the approximation tries to synchronize with the desired response curve in the positive region. All the simulations are done in MATLAB.

REMOVAL OF COMMERCIAL ANIONIC DETERGENT IN WATER USING CONTINUOUS PROCESS OF BIOLOGICAL REACTOR WITH ADDING OF PAC

Synthetic detergents, mostly anionic detergents have been widely used in Indonesia over past two decades, similar to its use in other developing countries, and residuals from such use have entered the country's riverine and estuarine systems. Detergent problems have become more serious especially in urban areas where the spread of sewerage systems are still low, even in drinking water treatment process. According to this reason, it is important to develop low-cost technology to solve this problem such as developing biological treatment for removing detergents.Effects OF continuous adding of powdeR activated carbon (PAC) on biological removal of anionic detergent in continuous reactor was assessed. Results of these experiments showed that introduction of PAC into biological treatment of anionic detergent (ABS or LAS), has indicated significant effect on removal efficiency. Conducting continuous feeding of PAC into bench scale of continuous process system for removal of detergent has resulted better stability of MBAS removal efficiency, even when MLSS concentration in aeration tank dropped or MBAS concentration in influent water rose rapidly. With continuous addition of PAC, the MBAS removal efficiency was relatively constant even when the water temperature dropped rapidly. In other words, continuous feeding of PAC can improve the stability for shock loads or temperatures changes. At lower temperatures, micro organisms that were used for detergent removal in bench scale of continuous process system, need longer adaptation or acclimation periods compared with higher temperatures. Key Words: Commercial anionic detergent, biodegradation, biological reactor, powdered activated carbon (PAC).

Development of quality risk management in the clinical pharmacy field

ObjectivesTo develop a quality risk management process for the clinical pharmacy field by adaptation of quality risk management methods known from production and logistics.MethodsThe risk management process for clinical pharmacy...

An algebraic approach to identifying bottlenecks in linear process models of multifunctional energy systems

This paper presents an algebraic approach for identifying bottlenecks in continuous process systems where each process unit is characterized by fixed mass and energy balance relationships. In industrial applications, such a system is designed to produce a particular product portfolio. This is determined from the anticipated products market and is taken as a baseline state. A process plant is designed with the individual process units at the required size to meet the baseline portfolio, and typically additional margin for safety reason is considered. A simple approach to identify the bottlenecks is proposed and the product portfolio is changed by a given fraction relative to the baseline state. A bottleneck occurs when the available excess capacity of a process unit is insufficient to meet the incremental requirement. Two illustrative case studies demonstrate the proposed methodology.

Active pharmaceutical ingredient (API) production involving continuous processes – A process system engineering (PSE)-assisted design framework

A systematic framework is proposed for the design of continuous pharmaceutical manufacturing processes. Specifically, the design framework focuses on organic chemistry based, active pharmaceutical ingredient (API) synthetic processes, but could potentially be extended to biocatalytic and fermentation-based products. The method exploits the synergic combination of continuous flow technologies (e.g., microfluidic techniques) and process systems engineering (PSE) methods and tools for faster process design and increased process understanding throughout the whole drug product and process development cycle. The design framework structures the many different and challenging design problems (e.g., solvent selection, reactor design, and design of separation and purification operations), driving the user from the initial drug discovery steps – where process knowledge is very limited – toward the detailed design and analysis. Examples from the literature of PSE methods and tools applied to pharmaceutical process design and novel pharmaceutical production technologies are provided along the text, assisting in the accumulation and interpretation of process knowledge. Different criteria are suggested for the selection of batch and continuous processes so that the whole design results in low capital and operational costs as well as low environmental footprint. The design framework has been applied to the retrofit of an existing batch-wise process used by H. Lundbeck A/S to produce an API: zuclopenthixol. Some of its batch operations were successfully converted into continuous mode, obtaining higher yields that allowed a significant simplification of the whole process. The material and environmental footprint of the process – evaluated through the process mass intensity index, that is, kg of material used per kg of product – was reduced to half of its initial value, with potential for further reduction. The case-study includes reaction steps typically used by the pharmaceutical industry featuring different characteristic reaction times, as well as L–L separation and distillation-based solvent exchange steps, and thus constitutes a good example of how the design framework can be useful to efficiently design novel or already existing API manufacturing processes taking advantage of continuous processes.

Advanced Method For Sewage Water Treatment

Sewage is waste water carrying wastes removed from residences, institutions, and commercial and industrial establishments, together with such groundwater, surface water, and storm water as may be present. It is more than 99.9% pure water and is characterized by its volume or rate of flow its physical condition, its chemical constituents, and the bacteriological organisms that it contains. Increasing volumes of domestic, hospital and industrial wastewater are being produced in cities around the world. Cities in developing countries lack resources to treat wastewater before disposal. Even where expensive wastewater treatment plants are installed, only a small percentage of the total wastewater volume is treated before discharge resulting in rivers, lakes and aquifers becoming severely contaminated. So there is great need to treat waste water. We can treat such water by various methods. The contaminants in wastewater are removed by physical, chemical, and biological means. The individual methods usually are classified as physical unit operations, chemical unit processes, and biological unit processes, Although these operations and processes occur in a variety of combinations in treatment systems, it has been found advantageous to study their scientific basis separately because the principles involved do not change. We can achieve desire results with the help of PLC. Using PLC we want to develop an automated continuous process system for treating the waste water. Though the process seems to be simple but degree of automation is higher for proper operation of a system. In this paper we are discussing how we are going to develop this system, what is the basic theme of this system and how our ideas will be applicable to the theme. We have designed a control system particularly a batch process.

Development of Batch and Continuous Processes on Biodiesel Production in a Packed-Bed Reactor by a Mixture of Immobilized Candida rugosa and Rhizopus oryzae Lipases

In this study, transesterification and esterification were investigated in batch and continuous process using immobilized Candida rugosa and Rhizopus oryzae lipases. In the case of batch process, stepwise reaction method was investigated to prevent the lipase deactivation. Reaction conditions were as follows: temperature, 45 degrees C; agitation speed, 250 rpm; enzyme concentration, 20%; and water contents 10%. And then, conversion yield was 98.33% at 4 h. In the case of continuous process, circulation and long-term continuous system were investigated for development of efficient mass transfer system. Optimal reaction conditions were as follows: temperature, 45 degrees C; flow rate, 0.8 mL/min; and water contents, 10%. And then, conversion yield of biodiesel was 97.98% at 3 h. Especially, the maximum conversion yield using a mixture of immobilized lipases exceeded over 90% for 108 h in long-term continuous system under optimal reaction conditions (45 degrees C; flow rate, 0.8 mL/min; and water contents, 10%). These results should help in determining the best method for the biodiesel production and improving the design and operation of large scale by enzymatic systems.

Actuator fault-tolerant control for discrete systems with strong uncertainties

In this paper, a reliable control method is first proposed for discrete systems with strong uncertainties. Actuator fault compensation is also investigated based on state feedback controller. The reliable control approach uses analytical redundancy and does not need duplicated actuators. Fault compensation controller is designed using accommodation mechanism which compensates the fault effects. The closed-loop stability is established based on Lyapunov's sense. The novelty of this paper is in controller design part. This reliable control approach is applied to three-tank system. The fault compensation method is applied to winding machine in continuous annealing process systems. Applications of the proposed design indicate that the method is effective for three-tank system and continuous annealing process systems.

Status and prospects for development of polyester fibre and yarn production technology

Current production schemes for polyester fibres and textile and industrial yarn and the prospects for development of their production technology are examined. Changing to economical direct melt spinning processes and to use highly efficient units for separate and combined spinning-drawing of fibres and yarn spun from melt and granulate, increasing textile fibre spinning and texturing speeds, and introducing continuous process and product quality control systems are the main trends in the evolution of modern plants. Most of the attention is being focused on creating flexible process lines that make it possible to raise the quality, rapidly change the assortment, and manufacture products that satisfy market requirements.

OOONEIDA: An Open, Object-Oriented Knowledge Economy for Intelligent Industrial Automation

Open knowledge economy in intelligent industrial automation (OOONEIDA) is a new initiative for enabling decentralized, reconfigurable industrial control and automation in discrete manufacturing and continuous process systems. The goal of the OOONEIDA project is the creation of the technological infrastructure for a new, open knowledge economy for automation components and automated industrial products. This will be done by further development of the concept of reusable portable software modules (function blocks) and by their application in the time- and cost-effective specification, design, validation, realization, and deployment of intelligent mechatronic components in distributed industrial automation and control systems.

Creation of a Knowledge Economy for Intelligent Industrial Automation: OOONEIDA Community in IMS

OOONEIDA is a new initiative for enabling decentralized, re-configurable industrial control and automation in discrete manufacturing and continuous process systems. The goal of the OOONEIDA is the creation of the technological infrastructure for a new, open knowledge economy for automation components and automated industrial products. This will be done by further development of the concept of reusable portable software modules (function blocks), and by their application in the time- and cost-effective specification, design, validation, realization and deployment of intelligent mechatronic components in distributed industrial automation and control systems.

A study on the fault diagnosis of roller-shape using frequency analysis of tension signals and artificial neural networks based approach in a web transport system

Rollers in the continuous process systems are ones of key components that determine the quality of web products. The condition of rollers (e.g. eccentricity, runout) should be consistently monitored in order to maintain the process conditions (e.g. tension, edge position) within a required specification. In this paper, a new diagnosis algorithm is suggested to detect the defective rollers based on the frequency analysis of web tension signals. The kernel of this technique is to use the characteristic features (RMS, Peak value, Power spectral density) of tension signals which allow the identification of the faulty rollers and the diagnosis of the degree of fault in the rollers. The characteristic features could be used to train an artificial neural network which could classify roller conditions into three groups (normal, warning, and faulty conditions). The simulation and experimental results showed that the suggested diagnosis algorithm can be successfully used to identify the defective rollers as well as to diagnose the degree of the defect of those rollers.

FACTORS AFFECTING CRISIS MANAGEMENT1

ABSTRACT Effective crisis management depends on good judgment, good information, effective preplanning, and luck. Three out of these four elements can be affected before a catastrophic event occurs. If successful strategies are used for the first three elements, they greatly influence the fourth. This paper discusses these three areas against the backdrop of a crisis. Of these, first and foremost is judgment. In normal decision making, many errors in judgment occur. These errors are greatly accelerated during a crisis event. We will examine how being aware of these errors can facilitate an efficient and effective response. Another characteristic of crises, especially in the early hours, is lack of information. Ambiguity overlies initial actions as the emergency unfolds and sometimes escalates uncontrollably. Crisis management includes defining information needs, dealing with short time frames and only a few hard facts, coping with pressure from inside and outside, eliminating destructive reaction patterns, and firmly deciding on and executing a plan for recovery. Lastly, this paper examines crisis in relation to contingency planning. There is little that can be done after an emergency that has not been thought about before the event. Preplanning must be part of any integrated system for emergencies. Dealing with “crises” begins with handling day-to-day procedures, identifying the best practices, developing the “what if's” within contingency planning, and exercising as a continuous process system.