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accountability; case studies; empirical research; environmental science; issues and policy; politics; process design
Abstract:
... Reflexive and deliberative knowledge co-production processes are increasingly used in dealing with contemporary sustainability challenges. These processes come with the need to develop ways to properly assess and understand their impact. In our case study, a three-year-long knowledge co-production process aimed at evaluating the Dutch nature policy, we observed that the actors involved valued and ...
absorption; bioinformatics; case studies; head; hydrodynamics; liquids; mass transfer; methane; methane production; models; prediction; process design; reaction kinetics; surface area
Abstract:
... Trickle bed reactors are one of the world’s most employed technologies for multiphase processing, and they have been scrutinized for decades. However, accurate prediction and scale-up of trickle bed reactors are still challenging owing to complex interactions of multiphase flow, interfacial mass transfer, and reaction kinetics. The present computational model provides an insight into process pheno ...
attitudes and opinions; case studies; chemists; colloids; computer simulation; computer-aided design; fields; industry; process design; wills
Abstract:
... Formulated products represent a particular class of complex chemical products, and their design is typically based on experience and extensive experimentation. Although still at an early stage, and despite that their potential is not fully accessed and not fully used by the industry, computer-aided design (CAD) methods and tools offer many possibilities in the design of formulated products. The CA ...
batteries; case studies; chemistry; data collection; issues and policy; process design
Abstract:
... This paper proposes a deep-learning-based optimal battery management scheme for frequency regulation (FR) by integrating model predictive control (MPC), supervised learning (SL), reinforcement learning (RL), and high-fidelity battery models. By taking advantage of deep neural networks (DNNs), the derived DNN-approximated policy is computationally efficient in online implementation. The design proc ...
adsorption; case studies; hydrogen; models; petroleum; process design; uncertainty
Abstract:
... A refinery hydrogen network is crucial for the processing of increasingly deteriorating heavy crude oil into light clean fuels, for which pressure swing adsorption (PSA) is indispensable in improving the hydrogen utilization efficiency and reducing the system cost. This study focuses on the simultaneous design of refinery hydrogen networks with the PSA configuration under uncertainty, which is a c ...
case studies; chemistry; computer simulation; equipment; methanol; models; prediction; process design
Abstract:
... The reactor is one of the most important equipment to be designed for optimal process operations. An appropriate reactor modeling leads to an efficient and optimal process conceptual design, simulation, and eventually construction. The key for success in this step is mainly related to kinetics. The present work is centered toward process simulation and aims at comparing three different kinetic mod ...
acetone; case studies; chemistry; glycerol; process design; thermodynamics
Abstract:
... The simulated moving bed reactor (SMBR) is a sorption-enhanced reactive technology that has been successfully applied to the synthesis of several organic compounds, due to its ability to overcome the thermodynamic limitations associated with reversible reactions. This work proposes the implementation of an innovative multifeed strategy that can considerably improve the performance of the SMBR, par ...
case studies; chemistry; process design; product quality; system optimization; uncertainty
Abstract:
... A new back-off methodology is presented to address mixed integer dynamic optimization (MIDO) formulations that arise from modeling the integration of scheduling and control of flow-shop batch plants under stochastic parametric uncertainty. The core idea of the methodology is to generate optimal scheduling and control decisions combined with optimal unit operation times that offer dynamic feasibili ...
case studies; chemistry; equations; freshwater; friction; irrigation; models; process design; water treatment; Chile
Abstract:
... Water resource management is a crucial issue today when global warming is advancing, generating water shortages in several world countries. Mathematical and optimization tools have addressed these problems, including new alternative water sources. Water networks are designed to cover consumption. In this context, pumping is critical in modeling water networks through optimization techniques becaus ...
administrative management; algorithms; analytical methods; biogas; case studies; energy conversion; environmental impact; hydrogen; hydrogen production; methane; natural gas; process design; steam
Abstract:
... Modern sustainable process design necessitates the use of sophisticated analytical approach to determine feasibility of design alternatives considering multiple criteria. This paper presents novel methodology for multi-criteria decision analysis (MCDA) considering economics, material and energy utilisation, inherent safety, and environmental impact. Its basis is the analytic hierarchy process (AHP ...
air; carbon dioxide; case studies; condensates; distillation; economic evaluation; energy efficiency; exergy; heat; loss prevention; oil and gas industry; process design; system optimization; temperature
Abstract:
... Gas condensate stabilization is a common process in gas refineries and petrochemical industries. This process is known as an energy consuming process because it uses distillation columns and furnaces for separating different cuts from the condensate feed. This study aims to improve the performance of the gas condensate stabilization unit in a large petrochemical company in terms of energy efficien ...
absorption; air; capital costs; carbon dioxide; case studies; coal; combustion; economic investment; energy; equipment; power plants; process design
Abstract:
... This study proposes a design and optimization framework for a membrane-integrated absorption CO₂ capture process for a coal-fired power plant. A modeling framework was developed for the hybrid capture process. The design was made by considering different flow-rate distributions between the combustion and sweep air for the membrane, as well as series and parallel configurations in an integrated man ...
case studies; coal; electricity; evaporation; exergy; heat; heat pumps; milk; natural gas; operating costs; process design; product safety; renewable electricity; systems engineering; temperature; vapors
Abstract:
... Industrial Process Integration and Electrification can provide an effective pathway to rapidly transition process heat in low temperature industries (i.e., heating <100 °C) away from coal or natural gas to renewable electricity. This paper aims to develop a highly efficient, completely electric milk evaporation system through the careful integration and selection of heat pump and Mechanical Vapour ...
algorithms; case studies; chemistry; gasoline; least squares; models; process design; supply chain; uncertainty
Abstract:
... Gasoline blending under uncertainty in the refinery value chain optimization has gained tremendous attention. This paper proposes a data-driven chance-constrained programming approach to address this issue and guarantee the benefit of the refinery value chain. First, the blending effect model is introduced to capture the uncertainties in component properties, where the blending effect value is est ...
case studies; chemistry; energy efficiency; exergy; liquefied natural gas; process design; refrigeration
Abstract:
... Production of liquefied natural gas (LNG) at a small scale typically relies on single mixed refrigerant (SMR) cycles to provide the necessary refrigeration. The shaft power required for refrigerant compression is by far the largest contributor to the operating costs of the entire LNG plant. The highly nonlinear interactions between operating variables mean that the optimization of these SMR cycles ...
abnormal behavior; algorithms; case studies; chemical industry; chemistry; data analysis; decision making; information management; process design; propionic acid
Abstract:
... Big Data Analytics plays a crucial role in Industry 4.0 by offering tools to improve the decision-making process. These tools comprise data management infrastructures and analytical methods. Among the economic sectors, the chemical process industry already holds mature data management structures but poorly explored analytical tools. In this sense, this work proposes an online analytical tool that ...
adsorption; case studies; process design; sorption isotherms; temperature
Abstract:
... Adsorption processes are typically designed with the aid of process simulators. Here, the extended Langmuir model and derivates are frequently used when dealing with type I isotherms (Langmuirian). The extended Langmuir model captures competition effects based on low-coverage Henry selectivity. However, it does not account for adsorbate size effects, where smaller adsorbates can be preferred at a ...
alcohols; case studies; databases; empirical research; molecular dynamics; process design; uncertainty; vapor pressure; vapors
Abstract:
... Vapor pressure is one of the most important properties needed when designing chemical processes. Experimental data are preferred; however, predictive methods must be used when data are not available. Even when experimental data are available, they are often sparse, and the quality needs to be evaluated. In this work, we have used the isomers of hexadecanol (C₁₆H₃₄O) for a vapor-pressure case study ...
Reynolds number; case studies; industry; models; process design; turbulent flow
Abstract:
... Pneumatic conveying with a diffuser is commonly used in the industry of thread locking for fasteners. During the coating operation, colloidal particles are carried by transported gas and sprayed onto surface of fasteners through a diffuser. However, accumulation of particles is frequently encountered near the outlet of the coating diffuser, which deteriorates uniformity of particle distribution on ...
case studies; chemistry; energy; equations; heat transfer coefficient; neurons; prediction; process design
Abstract:
... Modern chemical process plants are typically very complex in nature due to the various material and energy recycling streams, including the implementation of process intensification in order to improve the sustainability factor. Looking at each individual unit operation, there are inherent nonlinear properties that may often involve physical and chemical phenomena occurring on different time scale ...
carbon; carbon dioxide; case studies; chemical structure; databases; density functional theory; equations; ionic liquids; models; process design; solubility; system optimization
Abstract:
... To identify optimal ionic liquids (ILs) for CO₂ capture, an efficient computer-aided IL design (CAILD) approach is desired. The traditional CAILD methods usually combine an equation of state with the UNIFAC-IL model to calculate gas solubility, which is computationally expensive and sometimes cannot give quantitatively satisfying results. In this contribution, a new CAILD approach is presented for ...
Europeans; agricultural outlook and situation; agronomy; case studies; cropping systems; decision support systems; experimental design; journals; learning; managers; process design; researchers; steers
Abstract:
... Addressing the issues that agriculture is currently facing requires disruptive innovations, which may be stimulated through a process of innovative design, enhancing exploration in specific situations. In the aim to equip this process, several researchers implemented 'design workshops'. Yet, the literature poorly describes the way to organize, implement and capitalize design workshops, in the view ...
algorithms; case studies; energy efficiency; exergy; liquefaction; liquefied natural gas; process design
Abstract:
... Energy-intensive single mixed refrigerant (SMR) cycles are employed to produce liquefied natural gas (LNG) at small scale. The energy required for refrigerant compression (shaft work) dominates the overall operating costs of the LNG plant. While current methods to minimize shaft work demand (e.g., exergy analysis) focus on the PRICO cycle, this paper shows that structurally modifying the configura ...
case studies; chemistry; mesenchymal stromal cells; probability; process design; raw materials
Abstract:
... A five-step method is proposed for determining the design space of mesenchymal stem cell (MSC) cultivation processes incorporating system dynamics and variabilities. The method uses mechanistic models to capture the MSC cultivation dynamics while performing stochastic simulation to consider influences of the variabilities at raw material, cell, process specification, and operation levels. Simulate ...
X-ray photoelectron spectroscopy; atomic force microscopy; case studies; chemical composition; crosslinking; dynamic vapor sorption method; polyamides; polymerization; process design; reverse osmosis; solutes; temperature; topology; trimesoyl chloride
Abstract:
... The complex structure of the active aromatic polyamide (APA) layer of reverse osmosis membranes needs to be precisely described for understanding and predicting solute rejection. A commercial reverse osmosis membrane (CPA2, Hydranautics) was chosen as a case study, and home-made APA films were prepared by free-standing interfacial polymerization of trimesoyl chloride (TMC) and m-phenylenediamine ( ...
case studies; chemistry; economic evaluation; electrolysis; electrolytes; energy; ethylene oxide; polymers; process design
Abstract:
... The participation of power-intensive chemical processes in demand response programs is seen to provide grid stability and potentially reduce the operating costs of these processes. Large-scale processes that require intermediate products that can be produced by demand response scheduling of a suitable preprocess are an option to be utilized as grid energy storage. In this light, we determine the d ...
case studies; distillation; feedstocks; industry; liquids; oils; prediction; process design; vapors
Abstract:
... Machine learning has proven effective for predicting properties of pure compounds from molecular structures, but properties of mixtures, in particular oil fractions, are rarely dealt with. At best, the bulk properties are estimated based on pure compound properties, linear mixing rules, and a reconstructed composition of the feedstock. As the detailed composition of such mixtures is rarely well de ...
batch systems; bioprocessing; case studies; chromatography; cost effectiveness; equipment; models; process design
Abstract:
... Continuous process is a promising alternative for tradition batch process in biomanufacturing, which has higher productivity and lower material consumption. However, despite the maturation of necessary technologies for continuous process, there are few discussion about optimization of full continuous process. One possible reason is that the continuous process is such a complex and interacted proce ...
case studies; chemistry; process design; uncertainty
Abstract:
... Industrial process systems need to be optimized, simultaneously satisfying financial, quality, and safety criteria. To meet all of those potentially conflicting optimization objectives, multiobjective optimization formulations can be used to derive optimal trade-off solutions. In this work, we present a framework that provides the exact Pareto front of multiobjective mixed-integer linear optimizat ...
algae; biofuels; biomass production; capital; case studies; cost effectiveness; fuel oils; lignocellulose; models; process design; pyrolysis; synergism
Abstract:
... The coprocessing of bio-oil and vacuum gas oil has been demonstrated as a cost-effective way to utilize bioenergy. A multiperiod model is built to design and optimize of the coprocessing system by integrating monthly changes of lignocellulosic biomass production and algae growth rate. The case study showed that the optimal configurations of a coprocessing system with a minimized total annual cost ...
... Alarm systems are of paramount importance to the safety and proficiency of process industries. These systems aim to notify the plant operators of any possible equipment malfunction or undesired situation. An imperfect alarm system may announce false alarms in the normal operation mode or fail to raise alarms in case of some abnormalities. One mechanism for improving alarm systems is alarm filterin ...
Saccharomyces cerevisiae; biochemical pathways; bioreactors; case studies; chemistry; econometric models; ethanol; least squares; mathematical models; prediction; process design; system optimization; yeasts
Abstract:
... The application of economic model predictive control (EMPC) techniques in bioprocesses is scarce due to limitations in obtaining accurate dynamic models. Simplified unstructured models (e.g., Monod) can be easily developed, but their prediction capacity is poor. On the other hand, models based on dynamic flux balance analysis (dFBA) of the detailed metabolic network appear as a promising alternati ...
batteries; carbon nanotubes; case studies; electrochemistry; electrodes; electrolytes; energy efficiency; graphene; iodides; magnetic fields; porosity; process design; surface area
Abstract:
... A novel approach named a magnetic flowable electrode (MFE) is proposed for the first time to enable enhancement of redox flow batteries (RFBs) performance. This approach enables the formation of a high active surface area electrode from magnetic nanomaterials, without the need to fabricate a self-supporting three-dimensional electrode structure. To form a simple MFE, magnetic modified carbon nanot ...
algorithms; batch systems; case studies; models; penicillins; phase transition; prediction; process design
Abstract:
... The performance of the batch trajectory tracking algorithm is affected by batch-to-batch variation, which includes irregular phase transitions and batch durations. The latent variable model predictive control is modified to obtain the desired specification by applying an online alignment to assign the prediction model and update the future reference. One of the multiple models is selected at every ...
bioethanol; case studies; chemistry; fuel cells; nonlinear models; principal component analysis; process design; system optimization
Abstract:
... This work presents a methodology for defining the controlled variables based on two interrelated procedures. On the one hand, a linear combination of the selected measurements is performed through a combination matrix developed from the principal component analysis theory. On the other hand, the optimal sensor selection is formulated as a multiobjective optimization problem, which is efficiently s ...
biodiesel; case studies; chemistry; feedstocks; globalization; models; process design; supply chain; sustainable development; trade; Iran
Abstract:
... In this paper, a multiperiod, multiobjective, and multiproduct second-generation biodiesel supply chain network is innovated, taking into account sustainable development and international resources and demand. The proposed model maximizes the total profit and positive social issues and minimizes the harmful environmental consequences of the network. Furthermore, as trade is nowadays considered to ...
Aronia; anthocyanins; biomass; case studies; citric acid; homogenization; models; pH; pomace; process design; response surface methodology; solvents; temperature; wastes
Abstract:
... The recovery efficiency of waste valorization processes depends on an interplay of different conditions that are sometimes overlooked. Process optimization by the means of establishing mathematical relations between the process parameters and outputs is a strong tool to identify optimal operating conditions based on experimental data. In this study, the extraction of anthocyanins from chokeberry ( ...
case studies; chemometrics; infrared spectroscopy; least squares; nontarget organisms; process design; radioactive waste; remediation
Abstract:
... One of the challenges associated with multicomponent mixture analysis using chemometrics models is collecting calibration data. Depending upon the number of constituents, the size of the calibration set can be quite large. In some cases, the mixtures may contain numerous species, but only a small subset is central to the process for which quantification is being undertaken. For example, nuclear wa ...
algorithms; case studies; chemistry; process design
Abstract:
... The main technical approaches to solving nonlinear systems are based on numerical computation in the field of process systems engineering (PSE). However, the convergence and reliability of numerical methods are not always guaranteed due to numerical instability. Symbolic computation benefits from the accuracy and completeness of the solution compared with numerical methods. However, symbolic compu ...
capital; capital costs; case studies; income; process design; raw materials; stoichiometry; symbiosis; temperature
Abstract:
... Carbon–hydrogen–oxygen symbiotic networks (CHOSYNs) provide a systematic multiscale framework for integrating multiple hydrocarbon processing plants. Earlier approaches have focused on high-level performance benchmarking using atomic and stoichiometric targeting techniques, which are subsequently detailed to identify the implementation strategies for allocation and processing. These sequential app ...
Fischer-Tropsch reaction; administrative management; agricultural wastes; automation; bark; biofuels; case studies; computer software; electricity; energy conversion; feedstocks; gasification; heat; infrastructure; markets; process design; straw; transportation; Hungary; Poland; Slovakia
Abstract:
... The conversion of agricultural waste materials such as bark or straw into 2nd generation biofuels constitutes an auspicious way to meet part of the future fuel demand in a sustainable way. The number of possible production routes is diverse, and the techno-economic analyses of these routes have been conducted in very different ways. The route involving gasification, gas purification, and a subsequ ...
byproducts; case studies; chemistry; industry; oils; process design
Abstract:
... In this paper, a novel and effective stiction detection method is proposed by combining K-means clustering and the moving window approach. As a byproduct, the proposed stiction detection method offers an estimation for the stiction band in sticky control valves. The proposed stiction detection method is tested in industrial case studies consisting of benchmark industrial control loops and control ...
case studies; chemistry; fuzzy logic; neural networks; process design; support vector machines
Abstract:
... High computational loads, time-consuming convergence, and simulation crashes are common when using process simulators for flowsheet optimization. In this paper, by replacing the large-scale physical process simulations by surrogate models, the optimization time and computational load are reduced significantly along with maintaining the accuracy and reliability. A gas-to-liquids (GTL) plant was use ...
air; case studies; electricity costs; heat; industrial wastes; models; process design; systems engineering; temperature; weather
Abstract:
... In many chemical plants, a variety of cooling systems, including circulating cooling water systems and air coolers, are widely used to remove industrial waste heat. Current approaches for the design and optimization of these systems have focused on the use of constant parameters, including fixed temperature and energy price. Moreover, the ever-changing weather conditions play a major role in the d ...
Fourier transform infrared spectroscopy; algorithms; amination; case studies; chemometrics; entropy; process design
Abstract:
... Transmission infrared in situ measurement technique was used to assess its feasibility for real-time process analysis. In particular, the advanced chemometric analysis by band-target entropy minimization (BTEM) was implemented to obtain pure component spectral estimates from the multicomponent reaction system. In this case study, the rhodium-catalyzed reductive amination of 1-decanal in thermomorp ...
case studies; computer-aided design; models; molecular dynamics; polymers; probability distribution; process design; quantitative structure-activity relationships; sulfonic acids; system optimization; temperature
Abstract:
... In this paper, a computer-aided polymer design (CAPD) framework with a stochastic optimization model is proposed for the design of perfluorinated sulfonic acid proton exchange membrane (PFSA-PEM) with desired properties. First, the requirements and target characteristics are identified and converted to property constraints. Then, the polymer design model is formulated as a stochastic optimization ...
case studies; chemistry; heat exchangers; process design; variance
Abstract:
... In this paper, the effect of control systems, as a missing (but significant) actor, on the performance of alarm systems is studied. The interplay of control and alarm performance is justified, and it is shown that a state-feedback controller, which is designed to achieve a good quality of control (in terms of minimum output variance), has both desirable and undesirable consequences on the performa ...
case studies; esterification; kinetics; liquids; polymers; process design; solvents; sorption; thermodynamics
Abstract:
... Resins are interesting catalysts for organic reactions, which are characterized by a remarkable swelling behavior upon exposure to liquids, typically resulting in selective sorption in the case of mixtures. Hence, when constructing kinetic models for reactions catalyzed by such resins, the component partitioning between the bulk liquid and polymer liquid and its effect on their thermodynamic activ ...
algorithms; case studies; chemistry; models; process design; statistical analysis
Abstract:
... A framework with a data-driven model based approach to compute and analyze the operability sets is presented. The computationally expensive steady-state simulations are replaced by machine learning models developed through statistical analysis of selected rigorous simulations. The entire solution manifold is computed using a high-dimensional continuation algorithm. The framework is applied to a pl ...
algorithms; case studies; data analysis; data collection; energy; environmental impact; manufacturing; models; prediction; process design
Abstract:
... The additive manufacturing (AM) process is characterised as a high energy-consuming process, which has a significant impact on the environment and sustainability. The topic of AM energy consumption modelling, prediction, and optimisation has then become a research focus in both industry and academia. This issue involves many relevant features, such as material condition, process operation, part an ...