Use Of Process Simulation Research Articles

Systematic conceptual design strategies for the recovery of metals from E-waste

As the consumption of electronics increases worldwide, significant strain is posed on both the availability of mineral resources and the accumulation of waste due to their disposal. Recovering valuable minerals from e-waste can potentially alleviate both. This paper discusses the systematic design of processes for the recycling of waste printed circuit boards (WPCB). After reviewing the relevant processing steps, the generation of processing superstructures is explained. Next, a formulation of the optimization problem is presented to identify the best processing pathway, and the use of process simulators to specify optimization-relevant parameters. These ideas are described in detail via a WPCB to metals case study.

Decentralization of sustainable aviation fuel production in Brazil through Biomass-to-Liquids routes: A techno-economic and environmental evaluation

The present study evaluated the influence of three strategies to improve the economic feasibility of sustainable aviation fuel (SAF) production through gasification and Fischer-Tropsch synthesis (GFT) of lignocellulosic biomass feedstocks in Biomass-to-Liquids (BtL) plants. Apart from the integration with sugarcane ethanol production and the use of economic incentives by the carbon credits market, we evaluated the decentralization of the production chain with fast pyrolysis (FP) units to densify the biomass into bio-oil, aiming to reduce feedstock transportation costs for biofuel production. These analysis made use of process simulation coupled with techno-economic assessment (TEA) and life cycle assessment (LCA).Carbon credits commercialization alone is not enough to enable the standalone GFT scenario with current prices (up to 30 US$/tonne CO2 eq avoided). However, integration into a 1G mill can decrease SAF production costs to as low as 0.4–0.7 US$/L and achieve over 70 g of CO2 eq avoided/MJ of SAF. The addition of the FP process for decentralization is a better option than a centralized production only for distances above 1,000 km. This is due to expenses with feedstock bio-oil being from 2 to 5 times higher than with the direct use of solid biomass. In conclusion, the path to make SAF production feasible lies in the integration with more mature routes and by relying on incentives from environmental policies, while the decentralization could help markets with highly disperse biomass availability.

Design of multi-loop control systems for distillation columns: review of past and recent mathematical tools

Abstract Design of a control structure in distillation columns involves selecting proper sets of manipulated and controlled variables (often including tray temperatures for inferential control of product compositions) and one-to-one pairing between the two sets. In this paper, various mathematical tools for achieving this goal are reviewed. First, traditional methods such as Singular Value Decomposition (SVD) and Relative Gain Array (RGA) that build upon a simplified steady-state or dynamic model of the column are explored. The role of optimization in systematizing the control design procedures is also investigated. Then, more recent inferential control techniques that rely on statistical methods such as Principal Component Regression (PCR), Partial Least Squares Regression (PLSR), and other machine learning techniques such as Artificial Neural Networks (ANN) and Support Vector Machine Regression (SVMR) are discussed extensively. The discussions include newer distillation technologies with complex configurations such as dividing-wall columns. Finally, the use of process simulators in aiding the control structure design of distillation columns is surveyed.

The use of process simulation in supercritical fluids applications

Modelling and simulation from micro- to macro-scale are needed to attain a broader commercialization of supercritical technologies.

Smart tool path generation for 5-axis ball-end milling of sculptured surfaces using process models

Abstract Efficient 5-axis milling of free form surfaces required smart parameter selection and tool path generation approaches. Current computer-aided manufacturing (CAM) technology offers limited flexibility and assistance for such purposes, where purely geometrical issues are considered. Consequently, the generated tool path may be off the high-performance milling parameters. In 5-axis milling, the efficient process parameter set usually vary along the tool path due to varying engagement conditions because of inherent reasons. In this paper, a novel approach is proposed for identification of efficient surface milling parameters according to the variation of cutting forces and stability along the tool path, and then continuously implementation of these parameters for smart tool path generation, obeying the geometrical requirements. The proposed approach is applied on representative cases relevant to industrial applications to demonstrate the benefits. It is shown that, use of process simulations in tool path planning and generation offers significant benefits in decreasing the total cycle time in 5-axis milling.

Process Modeling, Simulation and Optimization: From Single Solutions to a Multitude of Solutions to Support Decision Making

AbstractBesides experimentation process simulation is a key technology in process development. Process simulation supports design, analysis and operation of chemical processes and plants. A systematic use of process simulation and optimization in the process development workflow is beneficial for both the process model and experiments and enables to be more efficient and effective in process design. In the following it will be discussed how the application of process simulation and optimization has to be broadened to provide decision support for process development.

Computer Aided HAZOP Study Implementation Bottlenecks in Chemical Industry

Implementation of computer aided approach into hazard and operability (HAZOP) study is one of the most researched topics in the field of hazard identification improvement. However, acceptance of an automated HAZOP tool in the industrial practice is limited. This contribution provides retrospective analysis of application issues connected with the use of process simulations in computer aided HAZOP studies. As case studies, mathematical models utilising different sets of unit operations, e.g. plug flow reactor, continuous stirred-tank reactor, phase separator, heat exchanger etc. were analysed. Two different simulation platforms, commercial process simulator Aspen HYSYS and our own mathematical models in MATLAB, were employed. Relevant concerns regarding the use of process simulations in the HAZOP study such as model reliability and its parameter uncertainties effect on the HAZOP study output and interpretation variability of quantitative HAZOP deviations for process simulations are discussed. It is demonstrated that the application of process simulation is a feasible way to perform precise safety analyses of processes widely used in chemical industry. However, proper attention has to be paid to the construction and use of mathematical models in order to develop a suitable software solution.

Use of process simulator to enhance the teaching‐learning process of flow of fluids for engineering students

AbstractThis manuscript shows how a commercial process simulation software such as Aspen–Hysys can be implemented to enhance the learning experience of Chemical Engineering students in Fluid Mechanics. To this end, a 15 hr practical computer lab is taught as a complement to the Fluid Mechanics lecturer classes at the end of the semester which allow to summarize in a practical way the main concepts of internal flow of fluids. We revisited here five representative learning working cases of this practical lab which includes: pressure drops calculation in pipes and conduction accidents, study of the variation of fluid properties profiles along a piping network, liquid and gases pumping energy calculation, and the study of cavitation phenomenon by the calculation of the Net Positive Suction Head (NPSH) in pumps. The proposed practical cases are also solved with the mass and energy balances equations studied in the lecturer classes to verify the obtained results which additionally are discussed according to a number of questions proposed on each practical example. The students feedback and satisfaction survey shows an overall score of the Fluid Mechanics practical course by the students of 8.2 out of 10 showing that this computer lab improves the efficiency of the Fluid Mechanics course since it let students to better understand the behavior of fluids in motion and the basic methods for the analysis and preliminary calculations of a wide variety of problems encountered in internal flow of fluids.

Feasibility studies of a novel extrusion process for curved profiles: Experimentation and modelling

Abstract The work described in this paper concerns a novel method for directly forming curved profiles/sections from billets in one extrusion operation using two opposing punches. Its mechanics are based on internal differential material flow, and it has been given the acronym, differential velocity sideways extrusion (DVSE). A tool set enabling sideways extrusion to be performed using opposing punches moving with different velocities was used for a series of experiments in which punch velocity ratio and extrusion ratio were process parameters. Plasticine was used as a model work-piece material and a series of compression tests were undertaken, to determine its constitutive properties and gain an estimate of work-piece die friction for use in process simulation. Curvature of extrudate can be controlled and varied using a difference between the velocities of the two punches, defined by velocity ratio. Greater curvature is achieved with lower velocity ratio. Curvature is also dependent on extrusion ratio, an increase in which increases curvature, although curvature is less sensitive to it than to velocity ratio. The extent of work-piece flow velocity gradient across the die exit orifice, which causes curvature, has been identified. Severe plastic deformation of the extrudate occurs in a way similar to channel angular extrusion (CAE), thus a greatly promoted effective strain level is achieved, though it is not always uniform across a section. The inner bending region of an extrudate experiences maximum localised effective strain, which decreases with decrease in curvature. To the authors' knowledge this is the first publication in which extrudate curvature is deliberately induced using opposing punches with differential velocities. Although only fixed velocity ratio values have been used in the work described in this paper the ability to change during operation exists and the process has the potential for the production of a profile with different curvature along its length.

Bridging LCA data gaps by use of process simulation for energy generation

Life Cycle Assessment (LCA) is now a mature environmental management strategy that is internationally standardized. A cornerstone of LCA involves Life Cycle Inventory (LCI) databases, which are largely implemented in several types of research. Finding consistent and transparent LCI data for LCAs still remains difficult. Setting up inventory data can be one of the most labour- and time-intensive stages of LCA. It is often challenging due to the lack of appropriate data for the product system under study (e.g. for production of chemicals). With the aim of bridging this gap, this paper proposes the combined use of a process simulation tool, experimental process data and LCA for the computation of energy-related emissions in connection with a given process. The case studies address the environmental impact assessment associated with steam production from a gas turbine. The practical application of the methodological framework is that different operating conditions and technologies can be modelled and evaluated systematically by an energy production simulator, in order to mitigate the effect of lack of data on environmental impact assessments. The combination of LCA and process modelling enables various alternatives for the energy production process to be assessed and can thus be used as a support for decision-making in a system-based approach.

Simple Perturbation Scheme to Consider Uncertainty in Equations of State for the Use in Process Simulation

For use in sensitivity studies and robust optimization, uncertainties in thermodynamic models have to be considered in simulations. Instead of using less vivid confidence intervals of the models’ fitting parameters, this work proposes a perturbation scheme for the fugacity coefficients in the liquid phase which can be applied to any thermodynamic model including equations of state. The perturbation is tuned via physically vivid and comprehensible parameters which have a direct relation to experimental uncertainties. Perturbations of pure component properties and mixture properties are separately accessible. After giving the theoretical framework of the perturbation scheme, the benefits of the approach are demonstrated using process simulation examples.

Use of Process Simulation for Plant Debottlenecking

This paper was aimed to illustrate the use of process simulation tools to find bottlenecks in a chemical plant. In practice, finding the first bottleneck of a plant is simply by increasing the capacity. However, two questions remain, e.g. what would the next bottleneck be and how big the first bottleneck needs to be expanded until the next bottleneck is reached. These questions can be repeated until eventually the whole equipment in the plant needs to be debottlenecked. Since it is impossible to answer the above questions in practice, a process simulation approach is utilized. Relevant equipment data and a validated thermodynamic model are used to build such a model. Plant performance trials are taken into account to estimate practical parameters such as fouling coefficients and plate tightness. This work requires strong interactions between operational people, consistent data gathering, and process simulation skill. The approach used in this work has shown that a reasonably accurate model can be built. The result has shown that the model can identify the first bottleneck as confirmed on the field. Sequence of bottlenecks and their corresponding increment of capacity increase have also been identified. The simulation results also illustrate the use of process simulation for plant debottlenecking.

FRONT MATTER

<p><strong>PREFACE</strong></p><p>Indonesian Journal of Science and Technology (IJoST) is a peer-reviewed journal that aims to publish and disseminate innovative research articles on the latest developments in all fields of science and technology. The journal publishes original papers in English, which contribute to the understanding of science and improvement of the science and technology. Papers may be theoretical explanation (including computational), experimental observation and analysis, or combination from both theoretical and experimental analysis. The contribution should be unpublished before and not under consideration for publication in elsewhere. IJoST maintains a standard double-blind peer review process. The review process means that the identity with the author, and the reviewer are not known to each other. IJoST is an open-access journal, and in this issue IJoST does not charge for readers, authors, or their institutions for access to the journal articles. This journal was firstly be published on April 30, 2016, and issued every April and October in each year, published by Tim Pengembang Jurnal at Universitas Pendidikan Indonesia.</p><p>In this issue, we published eight papers, including six original research articles and two review papers. In this issue, we received papers from remarkable researchers in several countries in the world, including Belgium, Japan, Singapore, Malaysia, The Netherlands, and Indonesia. The first paper discussed enzymatic cleaning method for reducing membrane fouling in membrane bioreactor. The next paper presented about application of artificial neural network for predicting biodiesel production. In the third paper, authors discussed about comparison of air temperature under global climate change in Japan. In the fourth paper, authors discussed about kinetics and thermodynamic studies the adsorption of phenol on activated carbon. The fifth article presented sludge dewatering process control using principal component analysis and partial least square. The next paper discussed the use of process simulation for plant debottlenecking. The sixth paper is a review article regarding the use of agricultural waste for silica source material. The final paper is a review of high-temperature oxidation of steel in steam condition. We believe that this issue will give benefits for the improvement and the development of science and technology.</p><p> </p><p align="right">Bandung, April 2006</p><p align="right"> </p><p align="right">Editor</p><p align="right"> </p><p> </p>

PvT-Behavior of Polymers under Processing Conditions and Implementation in the Process Simulation

The development of high performance products at lowest possible product development-time and costs is the demand of the plastics industry today. A successful use of process simulation to describe the behavior of complex structures and to minimize the technical and economic risks for companies requires application and process-relevant material data.The pvT-behavior of polymers is an essential parameter for process simulations. Especially the dependence of the specific volume of pressure and temperature [1, 2] under process conditions is not mapped to the existing measurement methods.In this study pvT measurements were performed on selected amorphous and semi-crystalline polymers (PP, HDPE, POM, PBT, and ABS) with a Pirouette pvT device, a combination of a dilatometer and Couette rheometer. The specific volume was determined as a function of temperature (25-300°C) and at pressures ranging between 200-1000 bar. On top of that, the influence of the cooling rate was also investigated by pvT measurements performed at cooling rates of 0.1°C/s, 1°C/s and 100°C/s.The coefficients for the 2nd domain Tait pvT-model, which is implemented in the software Autodesk Moldflow, were determined by fitting the experimental pvT data and comparing them with the measured curves. As a result, the semi-crystalline polymers show a shift of the transition temperature to lower temperatures and a reduction in the specific volume in the melt is observed. For validation, in a case study shrinkage results in real were compared with the simulation.

ICOPE-15-1020 Hampson type heat-exchanger technology and economic evaluation for LNG re-gasification and power generation At LNG receiving terminals

The system for high utilization of LNG cold energy is proposed by use of process simulator. The proposed design is a closed loop system, and composed by a Hampson type heat exchanger, turbines, pumps and advanced humid air turbine (AHAT) or Gas turbine combined cycle (GTCC). Its heat sources are Boil-off gas and cooling water for AHAT or GTCC. The higher cold exergy recovery to power can be about 38 to 56% as compared to the existing cold power generation of about 20% with a Rankine cycle of a single component. The advantage of the proposed system is to reduce the number of heat exchangers. Furthermore, the environmental impact is minimized because the proposed design is a closed loop system. A life cycle comparative cost is calculated to demonstrate feasibility of the proposed design. The development of the Hampson type exchangers is expected to meet the key functional requirements and will result in much higher LNG cold exergy recovery and the overall system performance i.e. re-gasification. Additionally, the proposed design is expected to provide flexibility to meet different gas pressure suited for the deregulation of energy system in Japan and higher reliability for an integrated boil-off gas system.

Biopharmaceutical Process Optimization with Simulation and Scheduling Tools.

Design and assessment activities associated with a biopharmaceutical process are performed at different levels of detail, based on the stage of development that the product is in. Preliminary "back-of-the envelope" assessments are performed early in the development lifecycle, whereas detailed design and evaluation are performed prior to the construction of a new facility. Both the preliminary and detailed design of integrated biopharmaceutical processes can be greatly assisted by the use of process simulators, discrete event simulators or finite capacity scheduling tools. This report describes the use of such tools for bioprocess development, design, and manufacturing. The report is divided into three sections. Section One provides introductory information and explains the purpose of bioprocess simulation. Section Two focuses on the detailed modeling of a single batch bioprocess that represents the manufacturing of a therapeutic monoclonal antibody (MAb). This type of analysis is typically performed by engineers engaged in the development and optimization of such processes. Section Three focuses on production planning and scheduling models for multiproduct plants.

Reducing the cost, environmental impact and energy consumption of biofuel processes through heat integration

This study proposes a process design methodology based on the combined use of process simulation in Super Pro Designer with economic, environmental and energetic balances implemented in Matlab and heat integration using Aspen Energy Analyzer. We model a 2.4MMgal/year alkali-catalyzed biodiesel process using vegetable oil and a 40MMgal/year dry-grind corn based bioethanol production plant. Then, we analyse the cost, the environmental impact, and the energy required to produce one gallon of the desired biofuel. Finally, we determine the optimal heat integration strategy of the plant in order to reduce the cost, environmental impact and energy consumption associated to the biofuel production. In the case of biodiesel the cost is reduced from 2.27$/gal to 2.19$/gal, the environmental impact from 4.52kgCO2eq/gallon to 4.26kgCO2eq/gallon and the energy from 8274BTU/gal to 8410BTU/gal. Reductions are also obtained in the bioethanol plant in which the cost is reduced from 1.79$/gal to 1.75$/gal, the environmental impact from 4.97kgCO2eq/gal to 4.77kgCO2eq/gal and the energy from 24,681BTU/gal to 23,168BTU/gal.

Quantitative risk assessment integrated with process simulator for a new technology of methanol production plant using recycled CO2

The use of process simulators can contribute with quantitative risk assessment (QRA) by minimizing expert time and large volume of data, being mandatory in the case of a future plant. This work illustrates the advantages of this association by integrating UNISIM DESIGN simulation and QRA to investigate the acceptability of a new technology of a Methanol Production Plant in a region. The simulated process was based on the hydrogenation of chemically sequestered carbon dioxide, demanding stringent operational conditions (high pressures and temperatures) and involving the production of hazardous materials. The estimation of the consequences was performed using the PHAST software, version 6.51. QRA results were expressed in terms of individual and social risks. Compared to existing tolerance levels, the risks were considered tolerable in nominal conditions of operation of the plant. The use of the simulator in association with the QRA also allowed testing the risk in new operating conditions in order to delimit safe regions for the plant.

Combined simulation–optimization methodology to reduce the environmental impact of pharmaceutical processes: application to the production of Penicillin V

Abstract In this work, we present a systematic method for the optimal design of pharmaceutical manufacturing processes that allows decision-makers to assess economic and environmental concerns in the early stages of the process development. Our approach relies on the combined use of process simulation, multi-objective optimization, economic analysis and life cycle assessment. The pharmaceutical production plant design is mathematically formulated as a multi-objective mixed-integer dynamic optimization (moMIDO) problem, which is solved by a decomposition algorithm that generates as output a set of Pareto optimal solutions. The capabilities of the proposed methodology are illustrated through the production of the antibiotic Penicillin V.

Minimization of the nonrenewable energy consumption in bioethanol production processes using a solar‐assisted steam generation system

The multiobjective optimization of a corn‐based bioethanol plant coupled with a solar‐assisted steam generation system with heat storage is described. Our approach relies on the combined use of process simulation, rigorous optimization tools, and economic and energetic plant analysis. The design task is posed as a bicriteria nonlinear programming problem that considers the simultaneous optimization of the plant profitability and the energy consumption. The capabilities of the proposed methodology are illustrated through a 120,000,000 kg/year corn‐based bioethanol plant considering weather data of Tarragona (Spain). © 2013 American Institute of Chemical Engineers AIChE J 60: 500–506, 2014