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The idea of module-based plant design is to select equipment modules of-the-peg instead of designing plants completely tailor-made to speed up plant design. Using equipment modules in plant design leads to equipment that does not exactly fit requirements. For some process units of a plant this might result in a moderate increase of investment and/or operating costs; for others using equipment modules of-the-peg might lead to a substantial increase of costs. The key question is: For which process units of a plant can one afford increased costs due to equipment modules not exactly fitting the requirements? In this work the effect of using equipment modules on investment and operating costs is investigated. Three different preselection approaches to decide on the use of equipment modules are applied and evaluated. One is purely based on investment costs, whereas the two other approaches developed consider investment and operating costs, either directly or based on exergoeconomics. Using the fermentative production of succinic acid as case study, it is shown that investment and operating costs are equally important and that the preselection approach based directly on investment and operating costs is found most suitable when deciding on the use of equipment modules.

Plants evolved different strategies to better adapt to the environmental conditions in which they live: the control of their body architecture and the timing of phase change are two important processes that can improve their fitness. As they age, plants undergo two major phase changes (juvenile to adult and adult to reproductive) that are a response to environmental and endogenous signals. These phase transitions are accompanied by alterations in plant morphology and also by changes in physiology and the behavior of gene regulatory networks. Six main pathways involving environmental and endogenous cues that crosstalk with each other have been described as responsible for the control of plant phase transitions: the photoperiod pathway, the autonomous pathway, the vernalization pathway, the temperature pathway, the GA pathway, and the age pathway. However, studies have revealed that sugar is also involved in phase change and the control of branching behavior. In this review, we discuss recent advances in plant biology concerning the genetic and molecular mechanisms that allow plants to regulate phase transitions in response to the environment. We also propose connections between phase transition and plant architecture control.

The evaluation of a solar photovoltaic (PV) technology helps to identify its suitability for a specific location. The main objective of the present study is to assess the suitability of mono-crystalline silicon (mc-Si) and poly-crystalline silicon (pc-Si) PV modules with almost similar characteristics under Agadir climatic conditions. Electricity yield of these modules is calculated from the uninterruptible measured current–voltage curves from sunrise to sunset during a year. The influence of weather conditions, global irradiance and temperature, on the performances of the modules is assessed and as a part of considerations in the PV power plant design that the output power from pc-Si PV modules is found greater. Calculated annual average final yield (Yf), and performance ratio (PR) for mc-Si and pc-Si PV systems are (1602.22 kWh/kWp, 0.71), (1691.85 kWh/kWp, 0.75) respectively.

The P-graph framework was developed to solve Process Network Synthesis (PNS) problems in plant design. It provides a powerful engineering toolbox based on the constituent Maximal Structure Generation (MSG), Solution Structure Generation (SSG) and Accelerated Branch-and-Bound (ABB) algorithms. During the four decades of its development, the P-graph framework has proven to be capable of solving various engineering applications framed as PNS problems. This review paper gives a survey of the development of the P-graph framework, with emphasis on its enhancements and the diversification of applications in process engineering. Research gaps and promising directions for P-graph research are then discussed.

Upgrading technologies for producing a high quality biomethane from biogas are of growing interest due to phasing out of European feed-in tariffs for biogas-based electricity. Operators of small biogas plants need alternatives to common stationary upgrading plants due to their high investment cost. Mobile membrane-based upgrading plants can help to reduce those investment costs for single operators and therefore, new valorisation routes become accessible to them. Performance of membrane-based upgrading plants is highly dependent on the chosen plant design. As mobile upgrading plants are limited to a maximum of two stages for the membrane separation due to space and weight restrictions, performance can be influenced mainly by operational conditions and membrane module characteristics. In this study, the influence of the membrane's CO2/CH4 selectivity on the performance of the mobile upgrading plant was investigated. Rising the CO2/CH4 selectivity from 25 to 38.51 and 50 increased the recovery and the biomethane purity to a level comparable to those of stationary membrane-based upgrading plants.

Current challenges for (bio-)chemical industry require shorter project lead times. To reduce the lead time, the concept of module-based plant design was developed. Suitable equipment modules are selected from an equipment module database instead of time-consuming tailor-made equipment design. The quality of module-based plant design strongly depends on the quality of the equipment module database. An equipment module database should contain the least number of equipment modules covering as many industrial applications as possible. Hence, the generation of an equipment module database is a maximum coverage problem known from other disciplines, such as facility location. Within this work, the corresponding maximum coverage problem is formulated and solved by a randomized greedy algorithm. The approach for the generation of an equipment module database presented is exemplarily applied for liquid/liquid heat transfer applications provided by Evonik . It is shown, that less equipment modules are required for the same coverage of applications if the equipment module database is generated based on the maximum coverage problem than based on the existing methodology presented by Eilermann et al. (2017). Additionally, less computational effort is required.

The size of an agglomeration is expressed in population equivalent, referring to the maximum average weekly load during the year according to the European Directive 271/91. This quantity, multiplied by the daily biochemical oxygen demand (BOD) produced by one population equivalent (which is 60 g d

Every day, thousands of pupils, students, employees, and hospital patients eat food outside their homes that is cooked far from the place of consumption. The food service industry is responsible for supplying this food to schools, hospitals, nurseries, as well as to company canteens. The design, control, and management of food service operations is challenging given the complexity of such multiple facility production networks and entails multidisciplinary perspectives and competences. Both production and logistics operations play crucial roles and significantly affect the service performance as long as food products are prepared within a facility, and as long as they are distributed to multiple consumption sites. Hence, there are many planning decisions (e.g. the definition of the production facility location, the allocation of task to resources and the scheduling of production jobs), that are handled at different stages by different actors, who often decide based on their own practical experience and barely adopt integrated decision-support systems. A review of the literature shows that there is no integrated approach to support the design of food service production facilities, known as centralized kitchens (CEKIs). To facilitate such integration and assist food service managers to adopt quantitative and data-driven design approaches, this study proposes an original computer-based multidisciplinary decision-support tool for the design and configuration of a CEKI. The proposed tool aids decisions taken by multiple actors simultaneously through a set of interfaces driven by quantitative data that follow the logistical flow of materials throughout the CEKI (1), assesses performance indicators in a multidisciplinary dashboard (2), and implements what-if, multiple scenario analyses based on simulations (3). Graphical interfaces are designed to facilitate communication between the decision makers and the integration of data-driven analyses. The design of a new CEKI is used as a testbed for the decision-support tool. The real-world example highlights the interdependencies between issues and decisions and showcases how computer applications facilitate decision-making and improve communication between managers.

For a first-of-a-kind nuclear fusion reactor like ITER, remote maintainability of neutron-activated and contaminated components is one of the key aspects of plant design and operations, hence a fundamental ingredient of its success, as well as of the demonstration of long-term viability of fusion as an energy source. The whole ITER Remote Maintenance System (IRMS) is of unprecedented complexity and includes specifically developed technologies. Its procurement and start of operation will represent a major innovation to maintenance in hostile environments. Europe is a key contributor, with three remote handling (RH) systems, a.k.a. packages, plus a robotic inspection and metrology tool, currently under design. This paper gives an update on the status of design and procurement activities related to the IRMS. It will first introduce some key aspects of the reactor remote maintainability, and then give an overview of the present configuration of the global system. After this, the scope, status and challenges of the European (EU) packages will be illustrated in more detail, together with some key technological developments. Finally, the way all these efforts are coordinated will be presented together with the overall implementation scenario and milestones, and the way they fit with ITER construction and operation.

Wet process phosphoric acid plant design is well known, secrets are few and far in-between. The most common design when looking at world-wide production is Di-Hydrate. There are reasons for this fact, but those merits are not discussed herein. Despite the ubiquity and maturity in the state of design, there are still innovations yet to come. Over the past few decades, many physical improvements to equipment have been made as well as advances in digital controls. These have changed the face of our plants both in efficiencies and capacities. Even with this maturity of the industry, and past advancements in processing, there is still room for improvement. This presentation will discuss some of the newer developments as well as discussing some of the barriers for further development.

In this paper, we propose an improved L-shaped method to solve large-scale two-stage convex 0–1 mixed-integer nonlinear stochastic programs with mixed-integer variables in both first and second stage decisions and with relatively complete recourse. To address the difficulties in solving large problems, we propose a Benders-like decomposition algorithm that includes both (strengthened) Benders cuts and Lagrangean cuts in the Benders master problem. The proposed algorithm is applied to solve a batch plant design problem under demand uncertainty, and a planning problem under demand and price uncertainty. It is shown that the proposed algorithm outperforms the commercial solvers, DICOPT, SBB, Alpha-ECP, and BARON, for the problems with a large number of scenarios. Also, although the proposed algorithm cannot close the duality gap, it is proved that it can yield a lower bound that is at least as tight as the one from Lagrangean decomposition.

Based on a systematic and comparable energetic assessment of 6-axis industrial robots, manufacturers as well as users of such robots gain various possibilities for increasing their resource efficiency. The method described in this paper, which has been developed for this specific purpose, can nevertheless be transferred and extended to other complex assembly and manufacturing systems even with varying deployment scenarios. Thereby a cross-industrial benefit for optimal energetic operation of industrial manufacturing systems can be achieved. By establishing centralized hosting and evaluation of all result data sheets, a large data pool could be created, which can be used for TCO-analysis as well as energetic and resource-efficient plant (equipment) design and, last but not least, for optimization of single components of manufacturing systems.

This paper presents the restoration, functional upgrading and plant design carried out at the San Martino Castle, located in Parella. The castle was built in the XIII Century and had undergone extensions and transformations up until the XX Century. It has been recently refurbished with the introduction of new functions. The criteria that drove the plant design were: to give new life to the environment, to achieve adequate comfort levels and air quality; to respect the existing structures, minimizing or integrating terminals and distribution systems; and to install energy efficiency systems, as well as to minimize emissions and running costs.

Process flowsheet synthesis is one critical step in the design of any chemical process and is a key factor for consideration in plant operation and economic efficiencies. Previously an automated process flowsheet synthesis is outlined that using a systematic computational approach. This method considers the design and operation variables to converge to an optimum flowsheet using genetic algorithm (GA). In this study, this algorithm is implemented to investigate the potential for a hybrid process combining membrane and cryogenic separation to achieve an efficient and effective carbon dioxide (CO2) capture plant design. The optimum flowsheet is selected using an objective function by screening among a variety of random flowsheets. The studied objective function is a combination of three effective factors in the performance of a flowsheet for this process which are: permeate CO2 purity, CO2 recovery of the system, and energy penalty of the configuration. The outcome of the optimization algorithm is presented as a structurally and parametrically optimized process flowsheet. Within the defined constraints the algorithm estimates that the optimum configuration of a hybrid structure of the membrane/cryogenic system for a three membrane unit process can provide CO2 permeate purity of 0.941, CO2 recovery of 0.979 and energy penalty of 1.249 GJ/t. While the same values for a membrane-based CO2 capture system are 0.940, 0.865 and 3.722 for the optimum estimated flowsheet. The presented results for the optimum hybrid process in comparison with other options shows a promising possibility of exchanging conventional technologies with the proposed optimal configuration. These results along with a global optimality analysis demonstrate the value of automated process synthesis in developing optimal process flowsheet designs.

The design of multi-purpose batch plants is a challenging task, because the number of degrees of freedom for optimization is high. Important optimization variables are the scheduling, operating conditions and the sizes of the equipment items. Since all factors interact, a simultaneous consideration would be beneficial in order to reduce capital and operating costs. In this article, this complex task is tackled for a new case study of a sequential plant for protein production. The case study contains comprehensive models of the unit operations to evaluate equipment dimensions, mass balances and operating times. Variable changeover times and semicontinuous unit operations are considered. For optimization, a MINLP model is used that consists of smaller NLP and MILP submodels in order to simplify modeling. Simulation runs for different product demands are performed and it is shown that good solutions can be found in an adequate time.

Vapor barriers are widely used to contain the release of flammable mixtures in LNG facilities in the United States. The computational fluid dynamics (CFD) modeling tool FLACS has been validated and accepted for detailed consequence modeling of flammable vapor dispersion scenarios and includes capabilities to assess the impact of vapor barriers at varying heights and locations. While every plant design is unique and the optimization of vapor barriers often requires several iterations, guidance on where to begin is often limited. This paper will detail a parametric study on vapor barrier height and placement for different release rates to establish a basis for beginning a vapor barrier design.

Future power grids would be unstable because of the larger share of renewable and nuclear power sources. This instability might bring some additional difficulties to fusion plant installation. Therefore, the authors carried out a quantitative feasibility study from the aspect of grid stability through simulation. Results showed that the more renewable and nuclear sources are linked to a grid, the greater disturbance the grid experiences upon a sudden output interruption of a fusion power plant, e.g. plasma disruption. The frequency deviations surpassed 0.2 Hz on some grids, suggesting potential limitations of fusion plant installation on future grids. To clearly show the suggested limitations of fusion plant installations, a novel diagram was presented.

Based on the operational data from the Korea Water Resources Corporation (K-water), this study aimed to reduce the operation and maintenance (O&M) costs for 20 brackish water desalination plants in the island regions of South Korea. In addition, brackish water reverse osmosis (BWRO) and low-pressure reverse osmosis (LPRO) membranes were compared and evaluated in terms of reduction in specific energy consumption (SEC) for an island brackish water desalination plant. The high labor costs and plant breakdown accounted for most of the operating losses with low operation rates (less than 60% in 19 plants) and low water flow rates (less than 90% in 15 plants). Thus, in order to reduce the O&M costs of island region desalination plants, it was essential to optimize the plant design while increasing the operation and water flow rates. In particular, installation of the LPRO membrane has shown potential for SEC improvement (approximately 16%) due to high pressure pump optimization and high recovery. These operational strategies for island region desalination plants are applicable alternatives in terms of reduction in O&M costs and SEC.

For the development of a wind power plant, plant design and its project feasibility analysis are implemented with wind data observed by a met-mast at a target location. Since observation period/time of a met-mast is normally about one year before the plant design, correlation with long-term data existing in the neighborhood of the target location is used for hindcasting past met-mast data to reduce uncertainty in the feasibility analysis, which is called the Measure-Correlate-Predict (MCP) method. In this study, cyclostationary empirical orthogonal function (CSEOF) analysis as a new approach is employed to extend the 1.5-year offshore met-mast HeMOSU-1 data into 34-year long-term data based on the MERRA reanalysis dataset. Both the one- and two-dimensional CSEOF results are compared with that of the widely-used MCP method. The CSEOF method shows a similar level of accuracy to the existing method for mean wind speed, while the former exhibits a slightly better accuracy for the frequency distribution of wind speed and the capacity factor as an index related to the estimation of wind power generation. In additional hypothetical test based on reanalysis datasets, the 1D-CSEOF method shows, in general, a better performance than the conventional MCP method in terms of the accuracy of statistical properties of wind.

Safety Integrity Level (SIL), as defined in IEC 61511, is a widely used safety performance measure for safety instrumented functions. The standard IEC 61511 suggests several methods for SIL determination, ranging from fully quantitative methods to fully qualitative methods. The large number of safety functions to evaluate during plant design and the need to integrate multidisciplinary design and operation knowledge to achieve effective risk reduction has made necessary the use of multi-disciplinary-team workshop approaches. Two widely used methods in the Oil & Gas industry for SIL determination are Layer of Protection Analysis (LOPA) and Risk Graphs. Each of these methods has their own advantages and disadvantages. LOPA allows the required risk reduction to be incorporated into the SIL values with higher precision. This enables a more detailed consideration of the available protection layers and leaves an objective traceable record of the decision-making process. In contrast, the simplicity of Risk Graphs makes them convenient for screening a large number of safety functions. This can make Risk Graphs useful as a first screening pass prior to using LOPA. However, Risk Graphs are still widely used as a stand-alone method. This paper seeks to explore the differences between LOPA and Risks graphs and to investigate whether the Risk Graphs method can provide the same level of SIL determination rigor as LOPA. The paper aims to determine if the simplicity of Risk Graphs can make that method more efficient for cases when the number of safety functions to evaluate is considerable.

Biodiesel has risen as a potential energy carrier and alternative biofuel. Understanding the phase equilibria of systems formed by alkyl esters of fatty acids and alcohols is of great interest to biodiesel industry. Predictive thermodynamic models are essential for process simulators used for plant design and optimization. The Perturbed Chain form of the Statistical Associating Fluid Theory (PC-SAFT) is used in this work to predict the thermophysical properties, vapor–liquid equilibrium (VLE) and liquid–liquid equilibrium (LLE) of binary and ternary systems related to biodiesel processing. The PC-SAFT was able to accurately predict the VLE and LLE of mixtures involving different types of biodiesel. The phase behavior prediction for mixtures investigated in this work seems to be not greatly influenced by the dipole–dipole. Furthermore, the phase behavior of binary and ternary mixtures of biodiesel was successfully predicted using a transferable cross–association parameters approach.

The goal of this work is to propose a multiperiod mixed-integer linear programming model that integrates several decisions about multistage multiproduct batch plants. Usually, plant design was solved without considering operation decisions. The proposed approach considers not only production planning but also scheduling decisions. The time horizon consists of several periods in which deterministic variations in prices, products demand limits, costs, and raw materials availability are taken into account. The plant operates using different production campaigns along each time period. The proposed model allows not only finding the optimal plant structure (unit sizes and its duplication in parallel in each stage), but also the detailed production planning in every time period. In this way, this work enables to assess the trade-offs between the different involved decision levels, taking into account fluctuations along the time horizon. Fil: Fumero, Yanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; Argentina Fil: Moreno, Marta Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina Fil: Corsano, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; Argentina Fil: Montagna, Jorge Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; Argentina

Inherently safer and friendlier plant design offers a simpler, cheaper, safer solution that consumes less energy, requires less maintenance, and produces less waste and pollution. It is a solution that the chemical industry needs to continually adopt in the years ahead. Nevertheless, obtaining an inherently safer process/technology with respect to all potential hazards is quite unfeasible and may lead to conflicts in the alternative process selection. To resolve safety conflicts, thorough understandings of all the hazards associated with the process options are vital. This paper presents a systematic screening procedure for reviewing inherently safer design alternatives using a combination of three-stage ISD matrix tool and guide word approach. The proposed methodology was applied to the ammonia supply system with the objective to understand the trade-off of inherent safety toward the overall process. The results show that the proposed tool is capable of helping users understand the impact of modification toward the safety and implementation cost.

Simulation is widely used in design and optimization of mineral processing circuits to answer “what if” questions regarding the employment of different equipment and configurations. The questions could be answered better if the long-term economic impacts of different circuits are readily estimated within the designing stage, considering both economic and technical constraints and criteria. This paper introduces a new open source user-friendly techno-economic simulator developed in Matlab/Simulink that joins multivariate capital and operating cost models to technical models of equipment and estimates some economic analytical indicators of the circuits such as Net Present Value simultaneously when the circuit is being designed. The proposed approach enables the designer to easily consider the technical and economic interactions and tradeoffs. As a case study, the long-term economic impact of selecting different numbers of leaching tanks is investigated and it is shown that even the optimum number of tanks could be a function of discount rate of the project.

This paper investigates the constrained double-flash geothermal power plant design space across a range of brine and condenser temperatures. Silica deposition and/or turbine exhaust quality constraints reduce specific work output at most brine temperatures. Some combinations of brine temperature and condenser temperature are also shown to be infeasible. Reducing condenser temperature is shown to improve specific work output up to 47% with diminishing effect as brine temperature increases. Relaxing the silica constraint is shown to yield up to an 8% increase in specific work output. These results are useful to a plant designer in determining the value of installing improved condensing or silica control equipment.

Chemical productions operated in extreme conditions (high pressure, high temperature) require a detailed analysis of all potentially dangerous situations that can lead to a major industrial accident and thus cause a loss of life and property. Many accidents in the near or distant history underline the need of a detailed safety analysis in process industries, not only in the phase of plant design but also during the operation of the plant. It would be shown that simulation of a chemical unit using an appropriate mathematical model and the nonlinear analysis theory can be a suitable tool for safety analysis. This approach is based on mathematical modeling of a process unit where both the steady-state analysis, including the analysis of the steady states multiplicity and stability, and the dynamic simulation are used. Principal objective of this paper is to summarize problems regarding the model-based hazard identification in processes. A case study, focused on phenomena of multiple steady states in ammonia synthesis reactor will be presented. The influence of the model complexity and model parameters uncertainly on the quality of safety analysis would be underline.

In order to support the demonstration of a risk-informed approach to the design optimization of a sodium-cooled fast reactor (SFR), it was necessary to make realistic estimates of the consequences of severe accident scenarios. This paper describes the database, models, and assumptions used to estimate the offsite consequences of characteristic severe accident scenarios. As required for comparison with the NRC’s technology neutral framework limit curve, the offsite dose at one mile from the plant boundary is calculated using conservative meteorology. The reference plant design is a 1000 MWt pool-type design with metallic fuel. Because an integrated analysis tool comparable to MELCOR does not exist for SFR accident scenario analysis, it was necessary to write a computer code that would assess release of radionuclides from the fuel and transport within the reactor primary system and to link those analyses with results from existing computer codes that assess the dynamic response of the reactor, containment thermal–hydraulics, and radionuclide transport processes within the containment. The analyses indicate that the offsite source terms for SFR severe accident scenarios tend to be small because of the low melting temperature of the fuel, likelihood of significant retention of fission products within the sodium pool, augmentation of containment deposition processes by interaction with sodium oxide aerosols, and small driving force for release from the containment to the environment. A number of major sources of modeling uncertainty are identified as requiring further development effort. An integrated modeling capability, similar to the MELCOR code, is required to direct further research and ultimately to support the licensing of an SFR.

A model to track the dynamics of an outdoor photo-Fenton plant is proposed to design and scale up this kind of facility. This takes into account explicit variation in temperature and UV irradiation. The degradation of a paracetamol-contaminated wastewater was used to develop the model, first at lab scale and then at pilot plant scale in order to fine tune it. Provided with historical data on environmental conditions, an efficient design using the model is obtained with the Q UV method, which is the normal procedure, computing the accumulated energy per volume unit needed to reach a particular mineralization level. The application of the model allows scaling the plant on the basis of yearly environmental conditions and predicting the treatment capacity of the plant as a function of these environmental conditions. Additionally, plant performance can be compared for different locations as a function of UV radiation and temperature conditions. For a given yearly treatment volume goal, when moving from the best conditions to the worst conditions, a plant size five times higher was needed, whilst the Q UV needed to achieve the desired mineralization only increased three fold.

A detailed knowledge of the solar resource is essential for the planning and operation of solar energy systems. For characterizing the solar resource in a specific location over a longer period of time, such as 30 years, typical meteorological year (TMY) data sets are commonly used. The TMY comprises hourly values of solar radiation and meteorological elements for a 1-year period, chosen to represent ‘typical’ conditions in ten or more years of data. Consequently, TMY are not suited for designing systems to meet both the variability and the extreme conditions occurring at a location. In this work, probability distribution functions that contain the natural variability of the solar resource are analyzed. These distributions facilitate the generation of large data sets of monthly series of solar radiation; each of these yearly series can be seen as a feasible year and, therefore, possible years are used instead a median year that doesn’t contain information about variability or extreme conditions.

This paper aims at defining a design methodology for the global thermodynamic performance of a high altitude airship cabin. This design method applies to different systems, which could not use the traditional air conditioning plant layout based on bleed air intake from the compressor stage of jet engines. In the case of electrically propelled green vehicles and airships, other energy sources must be exploited. The MAAT EU FP7 project presents an innovative, energetically self sufficient, airship system based on cruiser-feeder architecture. Both the cruiser and feeder are fed by photovoltaic energy. The energy storage system by electrolysis and fuel cells with intermediate energy storage by hydrogen and oxygen is characterized by high temperature energy dispersions (about 800-1000 °C for High temperature SOFC cells). This situation encourages the definition of a novel pressurization and air conditioning system. A preliminary cabin sizing with some structural considerations, an energetic evaluation of the thermal insulation of the cabin and a general balance of the energy production system are provided

CSIRO researchers have been involved in the development of predictive metallurgical indices as a tool in the hydro- and geometallurgy fields. Rapid, small-scale, cost effective tests and protocols have been developed for comparative ranking of attributes relevant to leach performance, e.g. leach index (relative indication of leach performance), recovery, impurity deportment, reagent consumption and mineralogy of samples for their relative ranking. Results from these tests can be used for plant design or process optimisation to maximise the commercial value of an ore body and to minimise the social and environmental impact of mining operations. The motivation for development of these tests includes the reduction in use of traditional mineralogical tools, be they for reasons of accessibility, cost, speed or scale-up for processing of large sample numbers. Mineralogical analysis remains essential for validating leach results in the development of test protocols and as a means of quality control. This paper presents an accurate, robust statistical method for QEMSCAN data analysis that has been developed for use in conjunction with the geometallurgical leach tests.

The German High Temperature Reactor Fuel Development Program successfully developed, licensed and manufactured many thousands of spherical fuel elements that were used to power the experimental AVR reactor and the commercial THTR reactor. In the 1970s, this program extended the performance envelope of HTR fuels by developing and qualifying the TRISO-coated particle system. Irradiation testing in real-time AVR tests and accelerated MTR tests demonstrated the superior manufacturing process of this fuel and its irradiation performance. In the 1980s, another program direction change was made to a low enriched UO2 TRISO-coated particle system coupled with high-quality manufacturing specifications designed to meet new HTR plant design needs. These needs included requirements for inherent safety under normal operation and accident conditions. Again, the German fuel development program met and exceeded these challenges by manufacturing and qualifying the low-enriched UO2 TRISO-fuel system for HTR systems with steam generation, gas-turbine systems and very high temperature process heat applications. Fuel elements were manufactured in production scale facilities that contained near defect free UO2 TRISO coated particles, homogeneously distributed within a graphite matrix with very low levels of uranium contamination. Good irradiation performance for these elements was demonstrated under normal operating conditions to 12% FIMA and under accident conditions not exceeding 1600 °C.

Microalgae have the potential to be the feedstock for biofuels and laboratory scale electroflocculation was studied as a harvesting technique for marine microalgae. The effects of the electrode separation and mechanical mixing on the energy consumption were also assessed. Results were used to design a commercial scale electroflocculation plant for the estimation of the harvesting cost. By combining electroflocculation with mixing and settling, an overall energy consumption of 0.33 MJ m −3 has been achieved. On a large scale, the mixing can be made energy efficient by the use of a baffled hydraulic mixer. The total cost for the harvesting, including electrical energy, electrode metal dissolution and capital depreciation, is estimated to be $0.19 kg −1 of the ash free dry mass. Hence, electroflocculation has the potential to be more economical than other harvesting techniques for marine microalgae.

Models representing batch plants, especially flowshop facilities where all the products require the same processing sequence, have received much attention in the last decades. In particular, plant design and production scheduling have been addressed as disconnected problems due to the tremendous combinatory complexity associated to their simultaneous optimization. This paper develops a model for both design and scheduling of flowshop batch plants considering mixed product campaign and parallel unit duplication. Thus, a realistic formulation is attained, where industrial and commercial aspects are jointly taken into account. The proposed approach is formulated as a Mixed Integer Linear Programming model that determines the number of units per stages, unit and batch sizes and batch sequencing in each unit in order to fulfill the demand requirements at minimum investment cost. A set of novel constraints is proposed where the number of batches of each product in the campaign is an optimization variable. The approach performance is evaluated through several numerical examples. Fil: Fumero, Yanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo y Diseño (i); Argentina Fil: Corsano, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo y Diseño (i); Argentina Fil: Montagna, Jorge Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo y Diseño (i); Argentina

Fluor and E.ON have built a carbon dioxide recovery pilot plant using Fluor's proprietary Econamine FG PlusSM technology at E.ON's hard coal power plant in Wilhelmshaven, Germany. The capture plant is designed to recover approximately 70 Te/d of CO2 and will be used for data collection to facilitate scaling the design to a full sized coal power plant. The pilot plant has the configuration of a full size plant, including several technology improvements. The CO2 capture plant design includes technology advancements that are expected to lower energy demand, reduce costs, and improve the environmental signature of CO2 capture plant. The paper summarizes the technological advancements and initial results from the commissioning of the capture unit.

A method for optimizing a central receiver solar thermal electric power plant is studied. We parametrize the plant design as a function of eleven design variables and reduce the problem of finding optimal designs to the numerical problem of finding the minimum of a function of several variables. This minimization problem is attacked with different algorithms both local and global in nature. We find that all algorithms find the same minimum of the objective function. The performance of each of the algorithms and the resulting designs are studied for two typical cases. We describe a method to evaluate the impact of design variables in the plant performance. This method will tell us what variables are key to the optimal plant design and which ones are less important. This information can be used to further improve the plant design and to accelerate the optimization procedure., Comment: LaTeX, 11 pages, 8 figures

This study aims to provide the approach for inherent safety design of onshore LNG plants to be applied at the very early stages (concept definition phase) of the project development. Onshore LNG plant development project starts from the “Concept Definition” phase, where financial feasibility is estimated and major conditions, such as site location and plant foot print, are set. The inherent safety design basic criteria and design measures should be identified and selected when setting the basic conditions during the Concept Definition phase of the project development, such as the site location (relative location from populated areas), site condition (prevailing wind direction) and plant production capacity (number of process train, number of product tanks). The safety measures, which are usually not fully developed at the project early stages in the current design execution practices, are the emergency systems, which mitigate an accident escalation, the modularized plant and layout, and the tank selection. The inherent safety design measures discusses in this paper were identified based on the categories of plot plan, emergency system, and module plant application. The proposed approach will contribute to improve inherent safety design of onshore LNG plants and it will also yield schedule and cost benefits.

Colonial garden architecture with associated use of non-native plant species influences the identity of many tropical cities. In Indonesia, colonial planners argued for planting both native and non-native species. It remains unclear how far this suggestion was implemented in urban parks and if species proposed in colonial period still occur in the parks or got replaced by common non-native species, which are prevailing in other tropical cities. We first analyzed recommendations on the plant use in conceptual publications on the design of green structures in colonial Bandung. We then investigated species pools of planted woody species in differently aged parks in Bandung to test the hypothesis that remnants of historically recommended species are still present in the colonial parks. We anticipate that native species still exist in older parks while more recent parks show an increased percentage of non-native species that do not belong to the historical assemblages of woody species. The results show that species recommended in historical concepts occur more often in such parks created in colonial times, than in younger parks. Contrasting to other colonial cities, historical planting concepts for Bandung equally recommended native and non-native trees and a considerable number of species from local Javanese flora were proposed for city greening. However, in the recent species assemblages, non-native species clearly prevail (65%). It is thus challenging for the future development of the parks to raise awareness of the green colonial heritage and to strengthen the use of native species.

The Fukushima-Daiichi accident shook the world, as a well-known plant design, the General Electric BWR Mark I, was heavily damaged in the tsunami, which followed the Great Japanese Earthquake of 11 March 2011. Plant safety functions were lost and, as both AC and DC failed, manoeuvrability of the plants at the site virtually came to a full stop. The traditional system of Emergency Operating Procedures (EOPs) and Severe Accident Management Guidelines (SAMG) failed to protect core and containment, and severe core damage resulted, followed by devastating hydrogen explosions and, finally, considerable radioactive releases. The root cause may not only have been that the design against tsunamis was incorrect, but that the defence against accidents in most power plants is based on traditional assumptions, such as Large Break LOCA as the limiting event, whereas there is no engineered design against severe accidents in most plants. Accidents beyond the licensed design basis have hardly been considered in the various designs, and if they were included, they often were not classified for their safety role, as most system safety classifications considered only design basis accidents. It is, hence, time to again consider the Design Basis Accident, and ask ourselves whether the time has not come to consider engineered safety functions to mitigate core damage accidents. Associated is a proper classification of those systems that do the job. Also associated are safety criteria, which so far are only related to ‘public health and safety’; in reality, nuclear accidents cause few casualties, but create immense economical and societal effects . for which there are no criteria to be met. Severe accidents create an environment far surpassing the imagination of those who developed EOPs and SAMG, most of which was developed after Three Mile Island . an accident where all was still in place, except the insight in the event was lost. It requires fundamental changes in our present safety approach and safety thinking and, hence, also in our EOPs and SAMG, in order to prevent future ‘Fukushimas’.

The here presented applied research and development project is targeted to the development and application of new and improved techniques in plant design, performance analysis and process control. Hereto following the required steps are illustrated and the goals are outlined. The project covers the development of a previously patented anaerobic digestion process, adaption of flow cytometry as an analytical instrument and investigation of innovative ways of disposal of solid fermentation wastes. The preliminary experiences with a newly built research plant employing a novel anaerobic biogas digestion technique are discussed. In this paper the first outcomes concerning the construction and operation are discussed. A novel method of disposal of the fermentation wastes is also discussed and first results are shown.

The carbon in pulp (CIP) and carbon in leach (CIL) processes became firmly established in the gold mining industry in the 1980s, initially in South Africa and Australia, from where they spread rapidly to all the gold producing regions of the world. The percentage of annual global gold production by activated carbon-based processes grew from zero in the 1970s to almost 70% by the turn of the century, which represented a phenomenal rate of acceptance of a new technology by a traditionally conservative industry. The main reason for this rapid acceptance of the new technology was the fact that the first few large industrial plants in South Africa convincingly demonstrated better gold recoveries than the traditional filtration/Merrill Crowe process, with lower capital and operating costs. And as the plants developed an operating track record over their first few years of life, they proved to be remarkably robust mechanically, and highly tolerant of plant upsets, changes in feed composition and solution phase contaminants that had caused great problems in Merrill Crowe plants. These stellar attributes of the carbon-based gold plants have led to complacency and laziness in the industry, both at the new plant design stage, and with on-going optimization of existing plants. In many cases, basic “rules of thumb” that were developed as design criteria for the early CIP plants are still used today, with no appreciation of the factors that may cause one plant to perform quite differently from another. There seems to be little incentive to improve performance when it is well known that most CIP and CIL plants operate quite well with minimal optimization and, in many cases, minimal understanding of the factors that influence performance. Consequently, almost all CIP and CIL plants are overdesigned at the construction stage and are then operated sub-optimally. This can lead to higher gold losses and/or higher capital and operating costs than necessary. This paper examines the factors that influence CIP and CIL plant design and performance, and demonstrates a very simple methodology that can be used to arrive at something close to an optimum plant design. It can also be used as an on-going tool by plant metallurgists to transform a fairly well run plant into an exceptionally well run plant.

Recent technical developments have made it possible to generate electricity from geothermal resources with low and medium enthalpy. One of these technologies is the Kalina Cycle System (KCS-34). In this study, electricity generation from Simav geothermal field is investigated. The optimum operating conditions for the KCS-34 plant design are determined on the basis of the exergetic and life-cycle-cost concepts. With the best design, power generation of 41.2 MW and electricity production of 346.1 GWh/a can be obtained with an energetic efficiency of 14.9% and exergetic efficiency of 36.2%. It is shown that, with the currently prevailing interest and inflation rates, the plant designs considered are economically feasible for values of the present worth factor (PWF) higher than 6. © 2010 Elsevier Masson SAS. All rights reserved.

Thermodynamic optimization of a multi-effect desalination (MED) plant has been performed. The effects of feed water flow rate, temperature of seawater, numbers of effects, temperature differences of preheaters and the outlet pressure have been studied. Tables for numerical calculations have been designed based on the DoE method. The effects of the foregoing parameters on the maximum and minimum distilled water have been investigated. In addition several contours have been presented to help a designer to find suitable conditions for a plant design.

Large industrial plants have often hundreds of heating and cooling heat exchangers. A common situation is that cooling demands of the processes are satisfied without any deeper analysis of the overall impact of the cooling systems on the plant’s economy or the environment. If cooling water is available it is used as much as needed and then pumped back to the river, some degrees warmer. An optimisation model was developed for integration of cooling and heating systems to tackle the problem. An industrial cooling system is a complex energy system comprising different options of producing cooling, distribution pipelines for cold media and cooling storages. Integration of power generation and heating systems to the cooling systems was included in the model. An illustrative example is presented in the paper. 10 process streams with cooling demand and 10 streams with heating demand were chosen, situated at different locations at the plant site. The optimal matches between the streams were found together with the sizes of the heat exchangers and the demands of hot and cold utilities. The costs of pipelines and the pumping costs of the streams are included in the model. The model can be used in the design of greenfield and retrofit investments and in versatile what-if analyses of the plant design or operation.

Over 100 papers were reviewed to elucidate factors influencing large-scale seawater desalination plants with reverse osmosis networks (SWRO). This paper consists of subjects such as SWRO systems investigation, system models of pretreatment and RO networks, systems optimization to minimize the total cost of SWRO plant design, and the future direction of SWRO technology. In order to design a large-scale seawater desalination plant, a systematic understanding of SWRO processes should be followed. After investigating all the processes, including site-specific features, seawater intakes, pretreatment systems, RO networks, energy recovery systems, post-treatment systems, brine disposal, and the environmental impact of SWRO desalination, system models are discussed for predicting the performance of each system. Based on the minimal principle of total cost required for a full-scale SWRO plant, optimized results are discussed. Studies needed for developing future SWRO technologies are suggested.

A general flotation circuit modeling framework has been developed. A robust and accurate flotation circuit model will be very useful for exploring flowsheet options, assisting in the correction of operational issues, comparing the performance of pilot- and full-sized plants, optimisation and control and plant design, among others. The framework is capable of fitting rate parameters, solving circuit mass- and volume balances and simulating the behavior of a specific ore in different circuits. This allows the researcher to explore various modeling options without concerns for the accuracy of the mass balance. The framework was tested on a data set generated as part of pilot plant experimentation. The regressed parameters were used to simulate various flowsheet configurations and sizing options. The framework proved to be a versatile tool for simulating changes to the flotation circuit configuration.

International audience; In this paper, we present PlantGL, an open-source graphic toolkit for the creation, simulation and analysis of 3D virtual plants. This C++ geometric library is embedded in the Python language which makes it a powerful user-interactive platform for plant modeling in various biological application domains. PlantGL makes it possible to build and manipulate geometric models of plants or plant parts, ranging from tissues and organs to plant populations. Based on a scene graph augmented with primitives dedicated to plant representation, several methods are provided to create plant architectures from either field measurements or procedural algorithms. Because they are particularly useful in plant design and analysis, special attention has been paid to the definition and use of branching system envelopes. Several examples from different modelling applications illustrate how PlantGL can be used to construct, analyse or manipulate geometric models at different scales ranging from tissues to plant communities.

A systematic step-by-step framework for analyzing hydrogen behavior and implementing passive autocatalytic recombiners (PARs) to mitigate hydrogen deflagration or detonation risk in severe accidents (SAs) is presented. The procedure can be subdivided into five main steps: (1) modeling the containment based on the plant design characteristics, (2) selecting the typical severe accident sequences, (3) calculating the hydrogen generation including in- and ex-vessel period, (4) modeling the gas distribution in containment atmosphere and estimating the hydrogen combustion modes and (5) evaluating the efficiency of the PAR-system to mitigate the hydrogen risk with and without catalytic recombiners, according to the safety criterion. For the Chinese 600MWe pressurized water reactor (PWR) with a large-dry containment, large break loss-of-coolant accident (LB-LOCA) is screened out as the reference severe accident sequence, considering the nature of hydrogen generation and the probabilistic safety assessment (PSA) result on accident sequences. The results show that a certain number of recombiners could remove effectively hydrogen and oxygen, to protect the containment integrity against hydrogen deflagration or detonation.

In recent years there has been continuing interest in the potential hazards from detonations in pipelines. The interest has arisen in several instances due to the introduction of vapour recover systems, as part of measures to limit environmental emissions. These environmental pressures initially coincided with the preparation of new European-wide test procedures for explosion arrester devices and, more recently, moves to develop a new international ISO standard for the certification and approval of detonation arrester devices. It is an opportune time therefore to review current understanding of explosion development in pipelines and to consider the implications for plant design and explosion arrester selection and testing.