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1.
Over the last few years the impact of products from natural sources in food, nutraceuticals, cosmetics, flavors/fragrances, and also the pharmaceutical industry has increased due to the consumer demand for nature‐derived products. Meeting this demand requires that existing manufacturing processes have to be optimized and process development for a variety of new products, sometimes with short life cycles, has to be accelerated. A scientific literature review covering equipment and modeling for plant‐based extractions shows an enormous demand for new approaches in process design for solvent extraction, isolation, and purification of ingredients from botanical sources and its transfer from academic research into manageable solutions for industrial use. An approach combining the design of experiments and rigorous process modeling on the one hand and an intensified collaboration between different disciplines including process engineering, botany, and analytical chemistry on the other hand seems to be the only way forward to address the current issues and shortcomings systematically and efficiently. Hence, a standard apparatus for the assessment of the governing process parameters for plant‐based extraction processes is proposed.  相似文献   

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Production simulation is an established method in the discrete manufacturing industry and became common in the process industry in recent years. This method can be employed for performance measurements and capacity assessments of manufacturing, material and information flow processes. Applications include for example bottleneck analysis, assessment of investment decisions and the solving of sequencing problems. The paper gives a brief summary of the history of the method and describes the most significant basics. Beside a general overview on existing process industry activities the different kinds of applications of production simulation at Degussa AG are explained. The paper finishes with cost‐benefit reflections and perspectives on further simulation activities at Degussa AG.  相似文献   

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Residence time distributions (RTD) are often described on the basis of the dispersion or the tanks in series models, whereby the fitting is not always good. In addition, the underlying ideas of these models only roughly characterize the real existing processes. Two semi‐empirical equations are presented based on characteristic parameters (mean, minimum, maximum residence time) and on an empirical exponent to permit better fitting. The determination of the parameters and their influence on the RTD are discussed. The usefulness of the models is shown in this first part for single‐phase systems and for the continuous phase of multiphase systems using data from literature for laminar and turbulent flows in different apparatuses. A comparison with the results of other models is also done.  相似文献   

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In chemical industries, process diagnostics have traditionally been achieved using discrete sensors installed in the critical plant locations and linked into a plant control system. The usefulness of such an approach is limited, as important information about the processes is lost. This paper demonstrates a different way of looking into the spatial and temporal characteristics of the industrial processes by employing techniques of industrial process tomography. The principles behind tomographic measurements are outlined and examples illustrating the capabilities of this approach are presented. These include imaging of the processes confined within process vessels such as fluidization and nylon polymerization, as well as an example of a transport‐dominated process – flow in a pneumatic conveyor. The advantages, limitations and potential future uses of process tomography are discussed.  相似文献   

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The operational conditions for an aqueous two‐phase system (ATPS) for β‐galactosidase purification were optimized and applied to the design of a purification strategy as an alternative to the primary purification steps. The ATPS proved to be suitable for the recovery and primary enzyme purification. The purification process design developed by ATPS, diafiltration, ion exchange, and diafiltration/ultrafiltration was successful, yielding a more than tenfold purification. The purification strategy design resulted in a powerful integrated purification and recovery process, an evidence of the potential for a scale‐up of the β‐galactosidase purification process.  相似文献   

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The aim of this study is the investigation of mass transfer processes in the liquid‐liquid system toluene/water. The transfer of different organic solvents and the influence of surfactants on the transfer are investigated. The results are compared with data reported in literature and with ray‐tracing computations. In most experimental work concerning mass transfer in liquid‐liquid systems a gradient of concentration outside the droplet is neglected. For the experimental determination of such gradients digital holographic interferometry will be introduced.  相似文献   

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Extraction of sugar from sugar beets is a process optimized over decades based on experience gathered during production. This process improvement is achieved without any systematic approach for optimization which raised the question whether such a mature process can be further optimized effectively, applying methods developed in the last decade like statistical experiment design or physicochemical modeling. Viable areas of operation for the respective approaches will be assessed and discussed using the example of sucrose extraction from sugar beet. Operating conditions are optimized regarding extraction kinetics and equilibrium behavior. Physicochemical modeling, however, requires detailed information on phase equilibria, fluid dynamics, and mass transfer effects. Here, the phase ratio can be identified as a sensitive parameter and process performance like the HETP (high equivalent of a theoretical plate) value can be enhanced. Therefore, the volumetric productivity serves as indicator. Potentials of process design and process optimization by a combination of statistical design of experiments and physicochemical modeling approaches are assessed, and respective possibilities and limitations are discussed.  相似文献   

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The evolution of global energy supply chains leads to a raw material change in the chemical industry. Despite this change, the value‐added chains of the chemical industry have to keep up their output of diverse high‐quality products desired by the customers. C1 chemistry in combination with suitable conversion technologies yielding olefins and aromatics will play a key role in mastering this challenge. New chemical value‐added chains have to be developed and assessed, resulting in an increasing importance of conceptual process design. All this will take place in what Ghemawat has called the World 3.0, a globally linked but regionally diverse world. This diversity creates further challenges for process design in the chemical industries. A systematic concept to address these challenges is given here, including strategies for optimization and decision support.  相似文献   

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Emulsions now find a wide range of applications in industry and daily life. In the pharmaceutical industry lipophilic active ingredients as well as many nutritional products such as vitamins are often formulated in the dispersed phase of oil‐in‐water emulsions. Emulsions can be produced with different mechanical emulsification techniques. In the following review, the process of rotor‐stator systems and disc systems are compared to other popular mechanical emulsification systems. On the basis of experimental results from the authors' laboratory, a discontinuous gear‐rim dispersing system, discontinuous disc system, and a continuous high pressure system are compared with regard to their attainable mean droplet diameter and drop size distribution in an oil‐in‐water emulsion. It can be shown that dissolver discs with a very simple geometry attain very small mean droplet diameters and a very narrow droplet size distribution, comparable to the emulsions obtained with established rotor‐stator systems such as gear‐rim dispersers.  相似文献   

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Key performance indicators have become a common tool in bioprocess development, as they allow an objective and independent rating and ranking of process alternatives screened. A disadvantage of all key performance indicators developed so far is their strong focus on costs, which makes them neglect the influence of the production rate on the profit of the process. But, since both production costs and production rate have an equally strong impact, both should be considered when decisions have to be made. Therefore, two new key performance indicators are introduced in this work, one for batch and one for continuous processing. They combine product yield, purity performance, variable manufacturing costs, and production rate to one objective. Thereby, misguided trade‐offs between these four individual measures can be replaced by one key performance indicator. This ensures a systematic development of biochemical downstream processes.  相似文献   

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Using ionic liquid (IL) [C2MIM][PF6] as an additive could remarkably improve the performance of the acetonitrile (CAN) process, which is the most widely used distillation process to produce 1,3‐butadiene (1,3‐BT). In this work, a rigorous simulation of a new IL process to produce 1,3‐BT was carried out to evaluate the performance of IL additive on an industrial scale, using UNIFAC as the global thermodynamic model. Based on the simulation models, some key operation parameters, such as solvent ratio and reflux ratio, were determined by sensitivity analysis. Furthermore, a multi‐objective optimization was proposed and performed considering both the energy consumption and environmental impact (green degree) of the new process. A nonlinear mathematical model was established to express this multi‐objective optimization problem, which includes six decision variables and involves maximizing the green degree of the process, the purity and the recovery of 1,3‐BT, and minimizing the energy consumption of the process. The optimization results showed that the energy consumption of the IL‐containing process could be reduced by 22 % and that its green degree could be improved by 9.2 %.  相似文献   

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Process retrofit (PR) is becoming a key issue for many existing industrial chemical processes due to the changing prices and market conditions, the emerging new design methodologies, as well as to environmental regulations. PR is sometimes far more complicated than process grassroots design, and it is usually team‐based work in which many departments and disciplines are concerned. Thus, it is very important to rationally organize the work and cooperation of the team members involved in the PR project. In this paper, we present some insights on the significance of PR, the methods for identifying the bottlenecks, as well as the principles and strategies of completing a retrofit project. A systematic procedure for process retrofits is developed based on the experience of several industrial retrofit projects.  相似文献   

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It is a requirement of environmental protection that the vapor/air mixtures formed during the storage, transport and refilling of petrols be collected and that the vapor contained in these mixtures be recovered. By vapor balancing within the distribution chain, the vapor/air mixtures are returned to the distribution depots where they are intermediately stored in vapor tanks, if need be, and processed in vapor recovery and exhaust air cleaning units. The more comprehensive the technical measures of discharging, conveying or processing the vapor/air mixtures of flammable liquids, the greater the problems of explosion protection. In this contribution, petrol will serve as an example to present and elucidate the explosion protection measures to be taken in exhaust air cleaning or vapor recovery units.  相似文献   

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