scholarly journals Scale-Up of Decanter Centrifuges for the Particle Separation and Mechanical Dewatering in the Minerals Processing Industry by Means of a Numerical Process Model

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 229
Author(s):  
Philipp Menesklou ◽  
Tabea Sinn ◽  
Hermann Nirschl ◽  
Marco Gleiss
Keyword(s):  
Process Model ◽  
Numerical Models ◽  
Scale Up ◽  
Mining Industry ◽  
Industrial Process ◽  
Numerical Approach ◽  
Pilot Scale ◽  
Numerical Process ◽  
Minerals Processing ◽  
Decanter Centrifuge

Decanter centrifuges are frequently used for thickening, dewatering, classification, or degritting in the mining industry and various other sectors. Their use in an industrial process chain requires a sufficiently accurate prediction of the product and the machine behaviour. For this purpose, experiments on a smaller pilot-scale are carried out for scale-up of a decanter centrifuge, which is usually a major challenge. Predicting the process behaviour of decanter centrifuges from laboratory tests is rather difficult. Basically, there are two common ways of scale-up: First, via analytical methods and the law of similarity, which often requires an enormous experimental effort. Second, using numerical models, which demands a mathematically and physically precise description of the multiple processes running simultaneously in such machines. This article provides an overview of both methods for scale-up of a decanter centrifuge. The concept of a previous developed numerical approach is introduced. Pros and cons of both scale-up methods are compared and further discussed. Experiments on lab-scale, pilot-scale, and industrial-scale decanter centrifuges with two different finely dispersed calcium carbonate water suspensions were carried out and simulations were done to investigate and prove the scale-up capability and transferability of the numerical approach.

scholarly journals New Scale-up Technologies for Hydrogenation Reactions in Multipurpose Pharmaceutical Production Plants

2021 ◽  
Vol 75 (11) ◽  
pp. 948-956
Author(s):  
Thierry Furrer ◽  
Benedikt Müller ◽  
Christoph Hasler ◽  
Bernhard Berger ◽  
Michael K. Levis ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Process Model ◽  
Scale Up ◽  
Pilot Scale ◽  
Hydrogenation Reaction ◽  
Production Scale ◽  
Hydrogenation Reactions ◽  
Scale Down ◽  
Physical And Chemical ◽  
Scale Reactor

The classical scale-up approach for hydrogenation reaction processes usually includes numerous laboratory- and pilot-scale experiments. With a novel scale-up strategy, a significant number of these experiments may be replaced by modern computational simulations in combination with scale-down experiments. With only a few laboratory-scale experiments and information about the production-scale reactor, a chemical process model is developed. This computational model can be used to simulate the production-scale process with a range of different process parameters. Those simulations are then validated by only a few experiments in an advanced scale-down reactor. The scale-down reactor has to be geometrically identical to the corresponding production-scale reactor and should show a similar mass transfer behaviour. Closest similarity in terms of heat transfer behaviour is ensured by a sophisticated 3D-printed heating/cooling finger, offering the same heat exchange area per volume and overall heat-transfer coefficient as in production-scale. The proposed scale-up strategy and the custom-designed scale-down reactor will be tested by proof of concept with model reactions. Those results will be described in a future publication. This project is an excellent example of a collaboration between academia and industry, which was funded by the Aargau Research Fund. The interest of academia is to study and understand all physical and chemical processes involved, whereas industry is interested in generating a robust and simple to use tool to improve scale-up and make reliable predictions.

Application of a temperature-controlled decanter centrifuge for the fractionation of αS-, β- and κ-casein on pilot scale

2021 ◽  
pp. 105148
Author(s):  
Thomas Schubert ◽  
Irem Ergin ◽  
Fiona Panetta ◽  
Jörg Hinrichs ◽  
Zeynep Atamer
Keyword(s):  
Pilot Scale ◽  
Temperature Controlled ◽  
Decanter Centrifuge

scholarly journals Pilot-Scale Production of Chito-Oligosaccharides Using an Innovative Recombinant Chitosanase Preparation Approach

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 290
Author(s):  
Chih-Yu Cheng ◽  
Chia-Huang Tsai ◽  
Pei-Jyun Liou ◽  
Chi-Hang Wang
Keyword(s):  
Cell Density ◽  
Scale Up ◽  
Cost Effective ◽  
Pilot Scale ◽  
Ionic Concentration ◽  
Dihydrogen Phosphate ◽  
Scale Production ◽  
Sodium Dihydrogen Phosphate ◽  
Selective Precipitation ◽  
Pilot Scale Production

For pilot-scale production of chito-oligosaccharides, it must be cost-effective to prepare designable recombinant chitosanase. Herein, an efficient method for preparing recombinant Bacillus chitosanase from Escherichia coli by elimination of undesirable substances as a precipitate is proposed. After an optimized culture with IPTG (Isopropyl β-d-1-thiogalactopyranoside) induction, the harvested cells were resuspended, disrupted by sonication, divided by selective precipitation, and stored using the same solution conditions. Several factors involved in these procedures, including ion types, ionic concentration, pH, and bacterial cell density, were examined. The optimal conditions were inferred to be pH = 4.5, 300 mM sodium dihydrogen phosphate, and cell density below 1011 cells/mL. Finally, recombinant chitosanase was purified to >70% homogeneity with an activity recovery and enzyme yield of 90% and 106 mg/L, respectively. When 10 L of 5% chitosan was hydrolyzed with 2500 units of chitosanase at ambient temperature for 72 h, hydrolyzed products having molar masses of 833 ± 222 g/mol with multiple degrees of polymerization (chito-dimer to tetramer) were obtained. This work provided an economical and eco-friendly preparation of recombinant chitosanase to scale up the hydrolysis of chitosan towards tailored oligosaccharides in the near future.

Analysis and Modeling of Defects in Unsupported Overhanging Features in Micro-Stereolithography

2016 ◽  
Author(s):  
Vito Basile ◽  
Francesco Modica ◽  
Irene Fassi
Keyword(s):  
Finite Element ◽  
Numerical Models ◽  
Numerical Approach ◽  
Fe Analysis ◽  
Test Cases ◽  
Layer By Layer ◽  
Failure Condition ◽  
Micro Scale ◽  
Part Geometry ◽  
Shape Component

In the present paper, a numerical approach to model the layer-by-layer construction of cured material during the Additive Manufacturing (AM) process is proposed. The method is developed by a recursive mechanical finite element (FE) analysis and takes into account forces and pressures acting on the cured material during the process, in order to simulate the behavior and investigate the failure condition sources, which lead to defects in the final part geometry. The study is focused on the evaluation of the process capability Stereolithography (SLA), to build parts with challenging features in meso-micro scale without supports. Two test cases, a cantilever part and a bridge shape component, have been considered in order to evaluate the potentiality of the approach. Numerical models have been tuned by experimental test. The simulations are validated considering two test cases and briefly compared to the printed samples. Results show the potential of the approach adopted but also the difficulties on simulation settings.

Model-based evaluation of a new upgrading concept for N-removal

2002 ◽  
Vol 45 (6) ◽  
pp. 169-176 ◽  
Author(s):  
S. Salem ◽  
D. Berends ◽  
J.J. Heijnen ◽  
M.C.M. van Loosdrecht
Keyword(s):  
Mathematical Modelling ◽  
Scale Up ◽  
Treatment Plant ◽  
Ammonia Concentration ◽  
Pilot Scale ◽  
Full Scale ◽  
Model Based ◽  
N Removal ◽  
Quantitative Basis ◽  
Treatment Concepts

Mathematical modelling is considered a time and cost-saving tool for evaluation of new wastewater treatment concepts. Modelling can help to bridge the gap between lab and full-scale application. Bio-augmentation can be used to obtain nitrification in activated sludge systems with a limited aerobic sludge retention time. In the present study the potential for augmenting the endogenous nitrifying population is evaluated. Implementing a nitrification reactor in the sludge return line fed with sludge liquor with a high ammonia concentration leads to augmentation of the native nitrifying population. Since the behaviour of nitrifiers is relatively well known, a choice was made to evaluate this new concept mainly based on mathematical modelling. As an example an existing treatment plant (wwtp Walcheren, The Netherlands) that needed to be upgraded was used. A mathematical model, based on the TUDP model and implemented in AQUASIM was developed and used to evaluate the potential of this bioaugmentation in the return sludge line. A comparison was made between bio-augmentation and extending the existing aeration basins and anoxic tanks. The results of both modified systems were compared to give a quantitative basis for evaluation of benefits gained from such a system. If the plant is upgraded by conventional extension it needs an increase in volume of about 225%; using a bioaugmentation in the return sludge line the total volume of the tanks needs to be expanded by only 75% (including the side stream tanks). Based on the modelling results a decision was made to implement the bioaugmentation concept at full scale without further pilot scale testing, thereby strongly decreasing the scale-up period for this process.

scholarly journals Cyber-Physical Industrial Control System Testbed: A Cyber-Security Solution

2020 ◽  
Author(s):  
Mohammad Nourizadeh ◽  
Mohammad Shakerpour ◽  
Nader Meskin ◽  
Devrim Unal
Keyword(s):  
Cyber Security ◽  
Process Model ◽  
Degrees Of Freedom ◽  
Industrial Process ◽  
Environmental Safety ◽  
Open Loop ◽  
Industrial Control ◽  
Systems Research ◽  
Process Plant ◽  
Real Risk

In this project, the hybrid testbed architecture is selected for the development of ICS testbed where the Tennessee Eastman (TE) plant is simulated inside PC and the remaining components are implemented using real industrial hardware. TE plant is selected as the industrial process for the developed cybersecur ity testbed due to the following reasons. First, the TE modTheel is a wellknown chemical process plant used in control systems research and it dynamics is well understood. Second, it should be properly cont rolled otherwise small disturbance will drive the system toward an unsafe and unstable operat ion. The inherent unstable open-loop property of the TE process model presents a real-world scenario in which a cyberattack could represent a real risk to human safety, environmental safety, and economic viability. Third, the process is complex, coupled and nonlinear, and has many degrees of freedom by which to control and perturb the dynamics of the process.

scholarly journals Evaluation of Fixed-Bed Cultures with Immobilized Lactococcus Lactis ssp. Lactis on Different Scales

2017 ◽  
Vol 11 (1) ◽  
pp. 16-25 ◽  
Author(s):  
Rebecca Faschian ◽  
Ilyas Eren ◽  
Steven Minden ◽  
Ralf Pörtner
Keyword(s):  
Dilution Rate ◽  
Lactococcus Lactis ◽  
Scale Up ◽  
Fixed Bed ◽  
Pilot Scale ◽  
Fixed Bed Reactor ◽  
Batch Mode ◽  
Promising Alternative ◽  
Fixed Beds ◽  
Pilot Scale Reactor

Fixed-bed processes, where cells are immobilized within macroporous carriers, are a promising alternative to processes with suspended cells. A scale-up concept is presented in order to evaluate the performance as part of process design of fixed-bed processes. Therefore,Lactococcus lactiscultivation in chemostat and batch mode was compared to fixed bed cultures on three different scales, the smallest being the downscaledMultifermwith 10 mL fixed bed units, the second a 100 mL fixed-bed reactor and the third a pilot scale reactor with 1 L fixed bed volume. As expected, the volume specific lactate productivity of all cultivations was dependent on dilution rate. In suspension chemostat culture a maximum of 2.3 g·L-1·h-1was reached. Due to cell retention in the fixed-beds, productivity increased up to 8.29 g·L-1·h-1at a dilution rate of D = 1.16 h-1(corresponding to 2.4·µmax) on pilot scale. For all fixed bed cultures a common spline was obtained indicating a good scale-up performance.

scholarly journals Automating multistep flow synthesis: approach and challenges in integrating chemistry, machines and logic

2017 ◽  
Vol 13 ◽  
pp. 960-987 ◽  
Author(s):  
Chinmay A Shukla ◽  
Amol A Kulkarni
Keyword(s):  
Industrial Process ◽  
Pilot Scale ◽  
Laboratory Scale ◽  
Flow Synthesis ◽  
Multistep Synthesis ◽  
Synthesis Strategy ◽  
Line Separation ◽  
Synthesis Approach ◽  
Scale Of Operation

The implementation of automation in the multistep flow synthesis is essential for transforming laboratory-scale chemistry into a reliable industrial process. In this review, we briefly introduce the role of automation based on its application in synthesis viz. auto sampling and inline monitoring, optimization and process control. Subsequently, we have critically reviewed a few multistep flow synthesis and suggested a possible control strategy to be implemented so that it helps to reliably transfer the laboratory-scale synthesis strategy to a pilot scale at its optimum conditions. Due to the vast literature in multistep synthesis, we have classified the literature and have identified the case studies based on few criteria viz. type of reaction, heating methods, processes involving in-line separation units, telescopic synthesis, processes involving in-line quenching and process with the smallest time scale of operation. This classification will cover the broader range in the multistep synthesis literature.

Two-Step Process Identification With Correlation Analysis and Least-Squares Parameter Estimation

1974 ◽  
Vol 96 (4) ◽  
pp. 426-432 ◽  
Author(s):  
R. Isermann ◽  
U. Bauer
Keyword(s):  
Correlation Analysis ◽  
Process Model ◽  
A Priori ◽  
Industrial Process ◽  
Computation Time ◽  
Small Computer ◽  
Nonparametric Model ◽  
Identification Method ◽  
On Line ◽  
Process Computer

An identification method is described which first identifies a linear nonparametric model (crosscorrelation function, impulse response) by correlation analysis and then estimates the parameters of a parametric model (discrete transfer function) and also includes a method for the detection of the model order and the time delay. The performance, the computational expense and the overall reliability of this method is compared with five other identification methods. This two-step identification method, which can be applied off-line or on-line, is especially suited to identification by process computers, since it has the properties: Little a priori knowledge about the structure of the process model; very short computation time; small computer storage; no initial values of matrices and parameters are necessary and no divergence is possible for the on-line version. Results of an on-line identification of an industrial process with a process computer are shown.

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