Sensitivity analysis of Austin's scale-up model for tumbling ball mills — Part 2. Effects of full-scale milling parameters

2017 ◽  
Vol 317 ◽  
pp. 6-12 ◽  
Author(s):  
François K. Mulenga
Keyword(s):  
Sensitivity Analysis ◽  
Scale Up ◽  
Full Scale ◽  
Ball Mills ◽  
Milling Parameters

Benchmarking of Truss Spar Vortex Induced Motions Derived From CFD With Experiments

2005 ◽  
Author(s):  
John Halkyard ◽  
Senu Sirnivas ◽  
Samuel Holmes ◽  
Yiannis Constantinides ◽  
Owen H. Oakley ◽  
...  
Keyword(s):  
Scale Up ◽  
Vertical Cylinder ◽  
Reynolds Numbers ◽  
Full Scale ◽  
Scale Model ◽  
Current Direction ◽  
Test Results ◽  
Helical Strakes ◽  
Truss Spar ◽  
Scale Data

Floating spar platforms are widely used in the Gulf of Mexico for oil production. The spar is a bluff, vertical cylinder which is subject to Vortex Induced Motions (VIM) when current velocities exceed a few knots. All spars to date have been constructed with helical strakes to mitigate VIM in order to reduce the loads on the risers and moorings. Model tests have indicated that the effectiveness of these strakes is influenced greatly by details of their design, by appurtenances placed on the outside of the hull and by current direction. At this time there is limited full scale data to validate the model test results and little understanding of the mechanisms at work in strake performance. The authors have been investigating the use of CFD as a means for predicting full scale VIM performance and for facilitating the design of spars for reduced VIM. This paper reports on the results of a study to benchmark the CFD results for a truss spar with a set of model experiments carried out in a towing tank. The focus is on the effect of current direction, reduced velocity and strake pitch on the VIM response. The tests were carried out on a 1:40 scale model of an actual truss spar design, and all computations were carried out at model scale. Future study will consider the effect of external appurtenances on the hull and scale-up to full scale Reynolds’ numbers on the results.

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 Theoretical and Experimental Sets of Choice Anode/Cathode Architectonics for High-Performance Full-Scale LIB Built-up Models

2019 ◽  
Vol 11 (1) ◽  
Author(s):  
H. Khalifa ◽  
S. A. El-Safty ◽  
A. Reda ◽  
M. A. Shenashen ◽  
M. M. Selim ◽  
...  
Keyword(s):  
High Performance ◽  
Density Functional ◽  
Coulombic Efficiency ◽  
Density Functional Theory Calculation ◽  
Scale Up ◽  
Lithium Ion ◽  
Building Blocks ◽  
High Energy ◽  
Full Scale ◽  
High Energy Density

Abstract To control the power hierarchy design of lithium-ion battery (LIB) built-up sets for electric vehicles (EVs), we offer intensive theoretical and experimental sets of choice anode/cathode architectonics that can be modulated in full-scale LIB built-up models. As primary structural tectonics, heterogeneous composite superstructures of full-cell-LIB (anode//cathode) electrodes were designed in closely packed flower agave rosettes TiO2@C (FRTO@C anode) and vertical-star-tower LiFePO4@C (VST@C cathode) building blocks to regulate the electron/ion movement in the three-dimensional axes and orientation pathways. The superpower hierarchy surfaces and multi-directional orientation components may create isosurface potential electrodes with mobile electron movements, in-to-out interplay electron dominances, and electron/charge cloud distributions. This study is the first to evaluate the hotkeys of choice anode/cathode architectonics to assemble different LIB–electrode platforms with high-mobility electron/ion flows and high-performance capacity functionalities. Density functional theory calculation revealed that the FRTO@C anode and VST-(i)@C cathode architectonics are a superior choice for the configuration of full-scale LIB built-up models. The integrated FRTO@C//VST-(i)@C full-scale LIB retains a huge discharge capacity (~ 94.2%), an average Coulombic efficiency of 99.85% after 2000 cycles at 1 C, and a high energy density of 127 Wh kg−1, thereby satisfying scale-up commercial EV requirements.

scholarly journals The Sensitivity of a Specific Denitrification Rate under the Dissolved Oxygen Pressure

2020 ◽  
Vol 17 (24) ◽  
pp. 9366
Author(s):  
Massimo Raboni ◽  
Paolo Viotti ◽  
Elena Cristina Rada ◽  
Fabio Conti ◽  
Maria Rosaria Boni
Keyword(s):  
Sensitivity Analysis ◽  
Dissolved Oxygen ◽  
Scientific Literature ◽  
Full Scale ◽  
Denitrification Rate ◽  
The Third ◽  
Small Influence ◽  
Denitrification Reactor ◽  
Activated Sludge Processes ◽  
Denitrification Process

The biological denitrification process is extensively discussed in scientific literature. The process requires anoxic conditions, but the influence of residual dissolved oxygen (DO) on the efficiency is not yet adequately documented. The present research aims to fill this gap by highlighting the effects of DO on the specific denitrification rate (SDNR) and consequently on the efficiency of the process. SDNR at a temperature of 20 °C (SDNR20°C) is the parameter normally used for the sizing of the denitrification reactor in biological-activated sludge processes. A sensitivity analysis of SNDR20°C to DO variations is developed. For this purpose, two of the main empirical models illustrated in the scientific literature are taken into consideration, with the addition of a deterministic third model proposed by the authors and validated by recent experimentations on several full-scale plants. In the first two models, SDNR20°C is expressed as a function of the only variable food:microrganism ratio in denitrification (F:MDEN), while in the third one, the dependence on DO is made explicit. The sensitivity analysis highlights all the significant dependence of SDNR20°C on DO characterized by a logarithmic decrease with a very pronounced gradient in correspondence with low DO concentrations. Moreover, the analysis demonstrates the relatively small influence of F:MDEN on the SDNR20°C and on the correlation between SDNR20°C and DO. The results confirm the great importance of minimizing DO and limiting, as much as possible, the transport of oxygen in the denitrification reactor through the incoming flows and mainly the mixed liquor recycle. Solutions to achieve this result in full-scale plants are reported.

From text-linguistics to literary actants—The force dynamics of (emotional) vampirism

2011 ◽  
Vol 3 (2) ◽  
pp. 235-282 ◽  
Author(s):  
Michael Kimmel
Keyword(s):  
Scale Up ◽  
Linguistic Analysis ◽  
Full Scale ◽  
Narrative Discourse ◽  
Text Linguistics ◽  
Force Dynamics ◽  
Dynamic Web ◽  
Coherence Patterns ◽  
Shed Light

AbstractThis article provides some groundwork for applying the cognitive linguistic theory of force dynamics (Talmy 1988, 2000) to narrative discourse. It proposes that Talmy's analytic apparatus is suitable for revealing character-related dynamics in literature, especially by exploiting the previously unnoticed convergence with the notion of actancy proposed by the narratologist Greimas (1966). Force imagery both in ordinary action descriptions and in metaphor opens a vista on how readers infer, stabilize, and elaborate narrative macro-representations of “who wants what” and “who does what to whom?” Hence, texts subtly encode aspects of higher-level story logic through forces, enabling readers (and scholars) to detect and scale up coherence patterns that shed light on character motives, protagonist interaction, and plot dynamics. A full-scale text linguistic analysis is proposed. My case study of about 500 text units found in Joseph Sheridan LeFanu's novella Carmilla (1872) reveals a dynamic web of driving, penetrating, manipulating, attracting, and erupting forces between the two main protagonists, a beautiful girl vampire and her 19 year-old victim.

Development of Glass Melter Technology for HLLW Vitrification in Japan

2014 ◽  
Author(s):  
Akira Sakai ◽  
Hajime Koikegami ◽  
Nobuyuki Miura ◽  
Eiji Ochi
Keyword(s):  
Noble Metals ◽  
Technology Development ◽  
Process Development ◽  
Scale Up ◽  
Liquid Waste ◽  
Glass Production ◽  
Full Scale ◽  
Acceptance Test ◽  
Radioactive Liquid Waste ◽  
Glass Melter

This paper describes the development of glass melter technology, primarily the liquid fed joule-heated ceramic melter process (LFCM) for the vitrificaton of high-level radioactive liquid waste (HLLW) since 1977 in Japan. In 2013 the active test at the vitrification facility (K-facility) in Rokkasho commercial reprocessing plant was successfully completed for the final acceptance test. During this period many activities on LFCM process development have been carried out in the engineering scale or the full-scale inactive cold tests including the radioactive laboratory scale hot tests. In particular, the design of melter bottom structure and the operating method should be optimized in order to avoid the operational problems caused by accumulation of noble metals (Ru, Rh, Pd), electro-conducive deposits on the melter bottom. Through the operation of inactive and active test facilities in Tokai, the design basis for the Tokai Vitrification Facility (TVF) has been provided. The hot operation of the TVF was started in 1995 to demonstrate the LFCM process including the performance of the melter off-gas clean-up system etc. The TVF has provided the basis of the process design and the operation method for the K-facility melter in Rokkasho. In case of commercial scale vitrification, the glass production rate of the melter should be several times larger than that of the TVF. The K-facility full-scale inactive mock-up melter (KMOC) has been planned to confirm the influence of scale-up factors and the difference between Tokai and Rokkasho wastes. Through the testing operation of the KMOC, which was initially started in 2000, it has been found that the stable formation of a cold cap on a molten glass surface is fundamentally important to avoid the excessive precipitation of noble metals and the yellow phase formation. The active test of the K-facility has been proceeding under the same conditions as the KMOC, and was successfully completed in May, 2013. The advanced glass melter development programs have also commenced from 2009 to ensure a more robust and noble metals are compatible with the LFCM system and also to provide a higher processing rate. The second K-facility full-scale inactive mock-up melter (K2MOC) has been installed in the vitrification technology development facility (X-14) at Rokkasho. Its testing operation has commenced from November, 2013.

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