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1
Wiggenhorn, Michael. "Scale-Up of Liposome Manufacturing". Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-84870.
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Mankosa, Michael James. "Scale-up of column flotation". Diss., This resource online, 1990. https://scholar.lib.vt.edu/ETD-db/ETD-catalog/manage_bound.
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Zauner, Rudolf. "Scale-up of precipitation processes". Thesis, University College London (University of London), 1999. http://discovery.ucl.ac.uk/1317927/.
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This thesis concerns the scale-up of precipitation processes aimed at predicting product particle characteristics. Although precipitation is widely used in the chemical and pharmaceutical industry, successful scale-up is difficult due to the absence of a validated methodology. It is found that none of the conventional scale-up criteria reported in the literature (equal power input per unit mass, equal tip speed, equal stirring rate) is capable of predicting the experimentally observed effects of the mixing conditions on kinetic rates and particle characteristics. As a result of high gradients in the supersaturation field during precipitation, particularly in the feed zone, high local gradients in the nucleation rate are to be expected. In this thesis, a compartmental mixing model (Segregated Feed Model SFM) linked to the population balance is proposed for scaling up both continuous and semibatch precipitation processes, and is validated with experiments on different scales. Experiments were carried out using two chemical systems (calcium oxalate CaC₂O₄ and calcium carbonate CaCO₃), varying the residence time/feed time, feed concentration, feed point position, impeller type, feed tube diameter and stirring rate in geometrically similar reactors ranging from 0.3 to 301. A new procedure is introduced in order to solve the inverse problem for determination of the kinetic parameters for nucleation, growth, disruption and agglomeration from the particle size distributions obtained in the continuous laboratory-scale experiments. This method, where the kinetic rates were extracted separately and sequentially from the particle size distribution, was found to be a reliable alternative to the conventional simultaneous estimation of all kinetic parameters from the distribution. Using the kinetic parameters extracted from the laboratory-scale experiments, the population balance is solved within the Segregated Feed Model. The local mixing parameters also required for solving the SFM are obtained from a sliding mesh Computational Fluid Dynamics (CFD) model. These are used to specify the different micromixing and mesomixing conditions in the feed and bulk zones of the reactor. The model accurately predicts the mean size, coefficient of variation and nucleation rate on different scales for different process and mixing conditions in both continuous and semibatch mode of operation. Furthermore, the model confirms the observed greater effect of mixing on product particle characteristics in semibatch than in continuous operation. This is thought to be due to direct mixing of the feed solution in semibatch operation with the other component already present in the reactor. The methodology proposed here for the scale-up of precipitation processes is very versatile and computationally efficient. It combines the advantages of both a CFD and a population balance approach without having to solve the equations together, which is currently still impracticable due to the excessive computational demand and simulation time required.
4
Smith, Keith Buchanan. "Scale-up of oscillatory flow mixing". Thesis, University of Cambridge, 2000. https://www.repository.cam.ac.uk/handle/1810/238305.
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Oscillatory Flow Mixing is a recent development in mixing technology which has evolved over the past decade. It has a number of similarities to other mixing technologies, particularly pulsed and reciprocating plate columns, but at the laboratory scale has demonstrated a number of advantageous properties. These properties (such as control of residence time distribution, improved heat transfer and predictable mixing times) have been demonstrated at the laboratory scale for a wide range of different potential applications, but until now there has been a lack of firm understanding and research into how the technology could be scaled-up into an industrial scale process. This thesis addresses the problem of scale-up in Oscillatory Flow Mixing. It reports on a programme of experiments on geometrically scaled apparatus with the measurement of residence time distributions and flow visualisation as the principal methods of investigating the wide range of flow conditions that can be achieved by control of net flow and of oscillatory conditions. Results from these investigations are interpreted as axial dispersion coefficients and also compared with results obtained computationally using a fluid mechanics approach to simulate flow fields and the injection of inert tracers into those flow fields. Significant clarification is reported concerning the analysis of axial dispersion measurements using the diffusion model for which conflicting solutions were identified in the literature. The development of a flow visualisation technique using fluorescent dye streaklines is also reported. Using the latter technique stable manifolds in Oscillatory Flow Mixing have for the first time been experimentally observed as well as a range of other flow regimes. The study of scale-up was extended by the successful construction and investigation of an alternative reactor geometry with the potential for use in large-scale plant. From the work presented in the thesis it is concluded that Oscillatory Flow Mixing is a technology which in general lends itself readily to scaling-up from laboratory to pilot plant scale, and most probably to industrial scale. Experiments performed on small laboratory apparatus (containing less than one litre of fluid) can with confidence be used to predict mixing behaviour in much larger plant (containing hundreds of litres of fluid.)
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Colby, Christopher Brett. "Optimisation of scale-up of chromatography /". Title page, table of contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phc686.pdf.
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Scholtzova, Angela. "Scale up and modelling of HPLC". Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368109.
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Davis, Ryan Z. "Design and Scale-Up of Production Scale Stirred Tank Fermentors". DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/537.
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In the bio/pharmaceutical industry, fermentation is extremely important in pharmaceutical development, and in microbial research. However, new fermentor designs are needed to improve production and reduce costs of complex systems such as cultivation of mammalian cells and genetically engineered micro-organisms. Traditionally, stirred tank design is driven by the oxygen transfer capability needed to achieve cell growth. However, design methodologies available for stirred tank fermentors are insufficient and many times contain errors. The aim of this research is to improve the design of production scale stirred tank fermentors through the development of dimensionless correlations and by providing information on aspects of fermentor tanks that can aid in oxygen mass transfer. This was accomplished through four key areas. Empirical studies were used to quantify the mass transfer capabilities of several different reactors. Computational fluid dynamics (CFD) was used to assess the impact of certain baffle and impeller geometries. Correction schemes were developed and applied to the experimental data. Dimensionless correlations were created from corrected experimental data to act as a guide for future production scale fermentor design. The methods for correcting experimental data developed in this research have proven to be accurate and useful. Furthermore, the correlations found from the corrected experimental data in this study are of great benefit in the design of production scale stirred tank fermentors. However, when designing a stirred tank fermentor of a different size, further experimentation should be performed to refine the correlations presented.
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Coleman, Simon James. "Scale-up of enface electrochemical reactor systems". Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/3071.
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Photolithography, the standard pattern transfer technique, has many sustainable issues due to the application of a mask to the substrate. A ‘maskless’ pattern transfer method, called the Enface technique, has recently been proposed for metal plating and etching. This method introduces the idea of bringing a patterned tool and a substrate together in close proximity and a current or voltage is passed between them enabling metal to be selectively deposited or removed from the substrate. The process requires sufficient electrolyte agitation within a narrow inter-electrode gap and has previously been shown to hold in a vertical flow channel reactor. However, the process has to be adapted for tank-type systems for industrial implementation. Mass transfer during electrodeposition can be enhanced by ultrasonic waves. It has therefore been investigated whether this would be an appropriate agitation method for Enface. In order to scale-up the process, 3 types of Enface reactors were investigated; a vertical flow cell, a 500 ml lab-scale tank-type cell and an 18 L ultrasound plating tank. The limiting current technique was used to study the mass transfer in these systems. Electrodeposition of copper pattern features in 0.1 M CuSO4 was achieved in each of these geometries. The scalability was quantified by measuring the uniformity of deposit roughness and deposit thickness of the features across the substrate using profilometry. The lab-scale tank-type cell with a 20 kHz ultrasound probe was used to investigate the effect of ultrasound agitation within narrow inter-electrode gaps. Mass transfer correlations showed that turbulent flow becomes fully developed when using ultrasound in this narrow geometry. Limiting current experiments showed that relatively low ultrasound powers of 9 – 18 W/cm2 should be used and current distribution modelling showed that the ultrasound source should be placed no less than 30 mm from the substrate. Copper pattern features were deposited onto 10 mm diameter substrates and using long current pulses with bursts of ultrasound during the off-time was the most suitable plating mode. Specially designed electrode holders in the large-scale 18 L ultrasound tank was used to deposit copper patterns onto larger substrates. Features of μm-scale were deposited onto A7 size substrates, but there was an unacceptable variation in deposit thickness of ±80% due to the non-uniformity of the electrode gap across the plate. However, mm-scale features were successfully deposited onto A7 size substrates with an acceptable deposit thickness uniformity and deposit roughness uniformity of ±18% and ±40% respectively across the plate. Enface is therefore currently scalable for mm-scale features on substrates of this size.
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Heider, Patrick Louis. "Scale-up of continuous chemical synthesis systems". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/86870.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 72-80).
Continuous flow systems for chemical synthesis have become increasingly important in the pharmaceutical and fine chemical industry in the past decade. Initially, this work was confined primarily to microfluidic systems, but recently there has been a growing demand for milliscale systems capable of making material for clinical trials and pilot plant testing. The objective of this thesis is to demonstrate a practical system to accomplish continuous chemical synthesis within the context of a fully integrated pilot plant. The plant provided a platform to test scaled-up membrane-based liquid-liquid separators which were studied in detail. Previous work demonstrated the use of microfiltration membranes to separate liquid-liquid systems by leveraging the dominance of interfacial tension over gravity at small scales. When scaling up, it was determined that pressure control was critical to the operation of the separators. A pressure control module was designed and integrated into the separator device to provide the appropriate conditions to guarantee separation. The separators required no outside control to accomplish separation when connected to various downstream conditions including pumps, backpressure controllers, and other separators. This allowed for easy design and operation of multistep processes such as solvent swaps and countercurrent extraction. The main accomplishment covered in this thesis is the building and operation of an integrated continuous manufacturing plant for a small molecule pharmaceutical product (aliskiren tablets). An advanced intermediate was continuously processed through two synthetic steps with workup which are detailed here. The remainder of the process purified and formulated the drug substance and formed the final tablet which met many key performance criteria. This work opens avenues to look at even more complex liquid-liquid and even gas-liquid separation processes. Improved processes for continuous manufacturing which make use of recycling, multistage extraction, and novel chemistries can build on the research performed here to further improve synthesis systems. These results demonstrate that continuous processes are possible even for complex, industrially-relevant products.
by Patrick Louis Heider.
Ph. D.
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Eraydin, Mert Kerem. "Scale-up of Using Novel Dewatering Aids". Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/27990.
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Coal preparation plants use large quantities of water for cleaning processes. Upon cleaning, the spent water must be removed such that the final product moisture level meets market constraints. However, removal of free water from the surface of fine particles is difficult and costly, and often the results are less than desirable. Fine particles inherently have very large surface areas, and hence retain large amounts of water. Increased amounts of fines also cause denser particle packing, which creates relatively small capillaries in filter cakes and, thus, cause slower dewatering kinetics. As a result, dewatering costs for fine particles are much higher than for dewatering coarse particles. Considering the technical and economic issues associated with dewatering coal and mineral fines, an extensive matrix of laboratory- and pilot-scale dewatering tests have been conducted to evaluate the use of novel dewatering aids. The reagents are designed to lower the surface tension of water, increase the hydrophobicity of the particles to be dewatered, and increase the capillary radius by hydrophobic coagulation. All of these are designed to lower the moisture of the filter cakes produced in mechanical dewatering processes. Laboratory-scale dewatering tests confirmed that using the novel dewatering aids can lower the final cake moisture of coal by 20-50%, while increasing the dewatering kinetics. Several on-site, pilot-scale tests were conducted to demonstrate that the process of using the novel dewatering aids can be scaled.
Based on the laboratory- and pilot-scale tests conducted, a scale-up model for the process of using the novel dewatering aids has been developed. It can predict the final cake moistures as a function of vacuum pressure, filtration time and specific cake weight. The model can be useful for the scale-up of vacuum disc filters (VDF) and horizontal belt filters (HBF). Simulation results indicate that dewatering aids can be very effective, especially when used in conjunction with HBF due to its ability to control cake thickness and drying cycle time independently.
In light of the promising laboratory- and pilot-scale test results, an industrial demonstration of the novel dewatering aids has been conducted at the Smith Branch impoundment site, which contains 2.9 million tons of recoverable coal. When the reagent was used for dewatering flotation products using a VDF, the moisture content was reduced from 26 to 20% at 0.5 lb/ton of reagent addition and to 17.5% at 1 lb/ton. The use of the dewatering aid also improved the kinetics of dewatering, increased the throughput, and reduced the power consumption of vacuum pumps by 30%.
The novel dewatering aids were also tested successfully for dewatering of kaolin clays. In this case, the mineral was treated with a cationic surfactant before adding the dewatering aids. This two-step hydrophobization process was able to reduce the cake moisture and also increase the throughput.Ph. D.
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Cai, Yusi. "Scale-up of Micro-structured Synthetic Paper". Thesis, KTH, Skolan för teknik och hälsa (STH), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215107.
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Dueñas-Espín, Iván 1979. "Scale up of Integrated Care for Chronic Patients". Doctoral thesis, Universitat Pompeu Fabra, 2016. http://hdl.handle.net/10803/482054.
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The current PhD thesis consists in a compilation of three papers aimed to analyze core drivers of Integrated care (IC) scale-up, namely: (i) assess the effects of anxiety and depression on physical activity in COPD patients as a use case of chronic patients; (ii) analyze health risk assessment strategies in the 5 regions participating in Advancing Coordinated Care and TeleHealth (ACT): Scotland (UK), Basque Country (ES), Catalonia (ES), Lombardy (I) and Groningen (NL); and, (iii) identify core characteristics of any given integrated care service and to generate a proposal for assessment of service outcomes using two use cases: complex chronic patients and patients requiring long-term oxygen therapy, in order to facilitate long-term follow-up of deployment at any given site and enhance comparability among deployment sites.La presente tesis doctoral consiste en una recopilación de tres artículos destinados a analizar los conductores centrales de la ampliación a gran escala de la Atención Integrada (AC), estos son: (i) evaluar los efectos de la ansiedad y la depresión sobre los niveles de actividad física en pacientes con EPOC como un caso de uso de pacientes crónicos; (ii) analizar las estrategias de evaluación de riesgos de salud en las 5 regiones que participan en el programa Coordinated Care and TeleHealth (ACT): Escocia (UK), País Vasco (ES), Cataluña (ES), Lombardía (I) y Groningen (H); y, (iii) identificar las características básicas de cualquier servicio de AI dado, para generar una propuesta de evaluación de los resultados del servicio utilizando dos casos de uso: los pacientes crónicos complejos y los pacientes que requieren terapia de oxígeno a largo plazo; esto con el fin de facilitar el seguimiento a largo plazo de despliegue en cualquier sitio dado y así mejorar la comparabilidad entre los lugares de despliegue.
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Bernard, William J. "The continuous rheoconversion process Scale-up and optimization". Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-082305-102150/.
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Engman, Randy W. "Cyclone scale-up and radial gas concentration profiles". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29937.
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A two part study was undertaken to explain the performance of cyclones operated in circulating fluidized bed combustion (CFBC) systems.
In the first part, collection efficiency tests were performed on a one-ninth scale polyacrylic cyclone model of the industrial scale cyclone at the 22 MWe CFBC facility at Chatham, New Brunswick. Emphasis was placed on scale-up considerations, loading effects, inlet geometry effects, and flow visualization trials. Experiments were performed at room temperature with inlet velocities between 3.7 and 5.5 m/s, solids loading between 0.05 and 7.5 mass solids/mass air with two different solids systems. There was disappointing agreement between the results from the Chatham unit, scaled according to Stokes Number scaling, and the findings obtained from the cold model unit. There was a minimum in the particle collection efficiency for particles of diameter 2.5 to 3.0 µm, apparently associated with agglomeration effects in the cyclone. Particle collection efficiency was found to increase with increased particle loading for the conditions studied. Changes in the inlet geometry gave inconclusive results. The experimental results were limited by problems associated with feeding and recycling the fines solids system used.
In the second part radial gas concentration profiles of a secondary cyclone serving the UBC pilot scale Circulating Fluidized Bed Combustor were performed at temperatures of about 870 ℃. Concentrations of O₂ , CO₂ , NO[formula omitted] , CH₄ , CO and SO₂ were measured. An increase in [CO], and to a lesser extent [CO₂], was measured near the cyclone wall. There appeared to be little radial variation in the concentration of other species.
Further work is required to allow the cold model to operate continuously, with particles which can be fed more freely, and to obtain radial gas concentration profiles within the primary cyclone of the UBC CFBC system.Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate
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Hsu, Kuang-Hsin. "Scale-up of affinity chromatography for protein purifications". Ohio : Ohio University, 2000. http://www.ohiolink.edu/etd/view.cgi?ohiou1172002240.
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Roy, Ratul. "Pressure fluctuations and scale-up in fluidised beds". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276197.
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Shaaban, M. G. B. "Scale-up studies on anaerobic dispersed growth digesters". Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372310.
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Bernard, III William J. "The Continuous Rheoconversion Process: Scale-up and Optimization". Digital WPI, 2005. https://digitalcommons.wpi.edu/etd-theses/957.
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"Semi-solid metal (SSM) processing has emerged as a preferred manufacturing method due to the superior quality associated with semi-solid castings. In recent years, the driving force to reduce process cost has led to the development of a few rheocasting (also termed slurry-on-demand) processes. These include UBE’s New Rheocasting (NRC) process [1], Idra Prince’s Semi-Solid Rheocasting (SSR) process [2], and THT’s Sub-Liquidus Casting (SLC®) process [3]. A novel slurry-making SSM process developed at ACRC/MPI, termed the “Continuous Rheoconversion Process†(CRP), is a passive liquid mixing technique in which the nucleation and growth of the primary phase are controlled using a specially designed “reactorâ€. The reactor provides heat extraction, copious nucleation and forced convection during the initial stage of solidification, leading to the formation of thixotropic structures. In these studies, the critical issues/challenges to optimize the CRP for industrial applications have been addressed through validation experiments and pre-industrial trials."
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Geldenhuys, Armand Stefan. "Scale-up behavior of the froth stability measurement". Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29876.
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Froth flotation is a widely used physio-chemical separation method in the minerals processing industry. Two distinct phases are present, namely: the pulp and froth phase. Flotation research has heavily focussed on the pulp performance; however only recently it was found that the froth performance contributes significantly to the overall flotation performance. Numerous parameters have been investigated to accurately quantify froth performance with the most notably being froth recovery. That being said, experimentally gathering data to obtain froth recovery is challenging and prone to large experimental errors. For this reason, the stability of the froth phase has been highlighted as a possible characterisation tool. Froth stability is defined as the time of persistence of the froth and is usually measured using either a dynamic and/or static methodology. Although measurement of froth stability has become common place in numerous flotation research articles, little to no attention has been given to the scale-up behaviour of the measurement. It is easily thought of that a froth constrained within a froth column will behave significantly different to one in an industrial flotation cell. Two common scale parameters, froth column diameter and initial pulp bubble size, was chosen to illustrate the dependence of the current methodology on scale. This does not mean that there are not vastly more parameters that would affect the measurement (column material of construction and/or column shape); however, these are two of the most easily changed parameters from experimental setup to setup. Four different column diameters were used for this study. Column diameter experiments were done on an industrial scale by means on manual tracking of froth growth versus time. Pulp bubble size experiments was performed on a laboratory scale by using different pore size glass frits while maintaining a constant superficial gas velocity. Dynamic stability for the pulp bubble size experiments were done by means of video tracking of froth growth versus time. The column diameter data sets highlighted similar behaviour – an increase in measured dynamic stability is seen with increasing column diameter up until a maximum is reached. This behaviour was attributed to the fact that wall films are thought to drain much faster than interstitial Plateau borders. As the column diameter decreases, the relative ratio of column surface area to bulk area increases and therefore results in an increased drainage rate a subsequently less stable froth. An empirical relationship was proposed to correct for the column diameter effect which is based on a ratio of bubble size to column diameter. The pulp bubble size data sets highlighted similar behaviour – an exponential decrease in measured dynamic stability is seen with increasing pulp bubble size. This behaviour was attributed to two fundamental mechanisms occurring within larger bubbled froths. Firstly, an increase in drainage rate as well as change in the drainage regime is seen as a function of bubble size; where in general froths of larger bubble sizes drain significantly faster. Secondly, on average froths consisting of large bubbles will have less water per volume of froth due to the decrease in bubble surface area. The effect of water content in a froth is well known and it can be said that wet froths experience less coalescence and bursting events. Therefore, the combination of the two mechanism is put forth as an explanation of the observed behaviour of the experimental systems.
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LA, NOTTE LUCA. "Scale-up of bulk-heterojunction polymer solar cells". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2013. http://hdl.handle.net/2108/203233.
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Polymer solar cells (PSCs) have recently reported a marked improvement in conversion efficiency, exceeding 10%, thus reducing the gap with more mature photovoltaic technologies. Now the transfer of such performances to the large scale has to be carried out by using industrially relevant techniques such as spray and slot die coating, and inkjet, gravure, flexographic and screen printing. This work is focused on the scale up of the PSCs by exploiting spray coating, a simple and low cost method already successfully applied to PSC layers. Firstly in literature a fully sprayed module was fabricated on glass substrate by an automated machine in air. Moreover, modules comprising a sprayed active layer were realized on flexible substrates. Both of them yielded ~1% of efficiency and supplied small power electronic devices. The aim to increase the efficiency of the modules addressed the activity towards two aspects. The first one concerned the investigation of new sprayable materials, i.e. low-temperature TiOX and PFN as interlayers and PBDTTT-C-T:PC71BM as active layer, all processed in safe solvents. The second one regarded the influence of the patterning methods, such as mechanical scribing and additive patterning through aerosol jet pre-printing, on the electrical parameters of the device. Finally, a lot of attention was focused on the stability issue. Encapsulation with commercial polymers was employed by heat sealing and this method revealed to be effective in the assembly of a fully solution-processed panel for greenhouse applications. Furthermore, the intrinsic stability of the device structure was analyzed; it was demonstrated that the electron transport layer and the solvent in which it is dissolved have a great influence on the device stability.
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Lee, Karen. "Scaling up public health interventions". Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/27829.
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The scale-up of effective or efficacious public health interventions to prevent chronic disease is important if population wide impacts are to be achieved. However, scale-up is complex and doesn’t happen as often as it should. This is despite growing interest in the area of research translation and scale-up by researchers and policy makers and a plethora of conceptual frameworks developed to guide the scale-up of efficacious interventions.
The objectives of this thesis are to understand how scale-up may be facilitated within a research translation framework as well as in the real-world by understanding the key factors that contribute to facilitating scale-up. A key finding from this thesis is that scale-up in the real-world does not occur in a linear fashion and is often influenced by a range of factors including the political and/or strategic context, values of key actors as well as community needs and the availability of funding. Furthermore, decisions to scale-up are not only determined by the level of evidence available, but also through the convergence of the abovementioned factors into an opportunity for scale-up, ‘the scale-up window’.
The opportunities to facilitate scale-up in this thesis include: cementing ‘scale-up’ as the end goal within a research translation framework which places the emphasis on scale-up equally alongside the other research translation activities; conducting research that promotes greater understanding of implementation and scale-up (through replication and scale-up studies) while reducing the traditional focus of smaller efficacy trials that are not conducive for scale-up; encouraging the uptake of pragmatic tools that provide guidance to those considering scale-up, through assessing the potential scalability of interventions considered for scale-up to expedite more informed decision making; and by comprehensively reflecting on and documenting scale-up experiences which contribute to capturing lessons for researchers and policy makers.
Finally, the field of scale-up may benefit from greater clarity around the ‘roles’ within research and policy settings on scale-up, which would increase the accountability for scaling up interventions as well as greater delineation between the growing field of implementation science and scale-up.
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Collin, Anne. "Strömungsmechanische Charakterisierung des Ringwirbelschichtreaktors im Hinblick auf Scale-up". Göttingen Cuvillier, 2009. http://d-nb.info/992645239/04.
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Winfield, Jonathan. "Scale-up of microbial fuel cells for wastewater treatment". Thesis, University of the West of England, Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.572852.
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For decades microbial fuel cells (MFCs) have offered the potential to treat wastewater while concomitantly producing power, but to date scale-up has not been achieved. The goal for this thesis was initially to explore the capabilities of MFCs in the laboratory and then to test the technology in the wastewater treatment environment. The aim was to operate the demonstrator in an existing process, without altering infrastructure or adding extra energy (Le. pumping). Laboratory work yielded novel findings helping to achieve the thesis objective while also contributing to MFC knowledge. Investigations into the anodic development period revealed that inoculating while in continuous-flow primed MFCs for operation in conditions of high flow-rate. The phenomenon 'power overshoot' was described and its occurrence explained in terms of the internal resistance of the MFC. A new miniature tubular MFC was designed and up to seven units were connected in fluidic series (cascade) to mimic the trickling filter process. These efficiently removed up to 90% COD, to levels that comply with European guidelines. The influence that fluidic connection had on MFCs in terms of flow-rate and external resistance was described for the first time. To mimic hostile flocculating conditions, MFCs were fed feedstock with varying ferric chloride concentrations. Power production, COD treatment, metal reduction and increased pH were all achieved suggesting the technology could supplement and improve existing processes. Utilising experience gained in the laboratory and following visits to Wessex Water, the trickling filter was selected as test location for the demonstrator. Using a variation on the novel tubular design, under field conditions at the Saltford treatment plant, MFCs demonstrated the ability to produce power while reducing COD to levels acceptable for release into the environment. These results strongly support the hypothesis that MFCs are becoming ready to be incorporated into the wastewater treatment process.
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Hoffmann, Achim [Verfasser]. "Scale-up von Reaktivrektifikationskolonnen mit katalytischen Packungen / Achim Hoffmann". Aachen : Shaker, 2005. http://d-nb.info/1181614651/34.
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Francis, Baker. "Scale-up and operations of a vertical stirred mill". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46044.
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Stirred media mills are relatively new to mining industry, and several new technologies have been developed such as the VXPmill (vertical stirred mill). There is little technical understanding of optimizing and scaling-up of the VXPmill. This thesis addresses both of these issues and therefore supports commercial applications of this vertical stirred mill.
Stirred media mills are influenced by a great number of operating variables. A study was conducted to understand the influence of mill speed, feed particle size and, slurry density and rheology on the VXPmill performance. For scale-up, a study was conducted to compare the batch recycle and the pendulum testing procedures. A scale-up demonstration study was also done utilizing the pilot-scale (VXP10) mill and the full-scale (VXP2500) mill to validate the procedure.
The following are the main findings from this work:
There is an optimum tip speed such that if too high (12 m/s) results in energy losses due to mechanical friction and heat. If too low (3 m/s) there are insufficient stresses to promote breakage. The optimum tip speed was found to be about 7 m/s.
Feed particle size is an important variable when predicting the energy-size reduction relationship. A coarser feed requires more energy than a finer feed to achieve the same grind size.
The batch recycle testing procedure overestimates the energy consumption as compared to the pendulum test over a broad range of grind sizes. Therefore, it should not be used for scale up applications. However, the pendulum test can be used to predict energy requirements for scale-up.
By utilizing the VXP10 mill, the stress intensity of grinding beads and specific energy input control the grind size for the comminution of feldspars-quartz ore. At optimum stress intensity, the energy utilization is maximum.
For the effective and accurate scaling-up of stirred media mills, it is extremely important that both the pilot-scale and the full-scale mills are operated at relatively similar operating conditions, and treating similar material of the same feed particle size. However, both mills should be operated at their optimal flow rates.
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Thomas, Sara. "Experimental design and scale-up methods for micellar floods". Thesis, University of Birmingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420520.
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Nieves, Remacha María José. "Microreactor technology : scale-up of multiphase continuous flow chemistries". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/91068.
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Thesis: Sc. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references.
Microreactors have been demonstrated to provide many advantages over conventional process technologies for the synthesis of chemical compounds and kinetic studies at the laboratory scale. High heat and mass transfer rates, rapid mixing, and higher selectivities and conversions can be achieved in these microdevices thanks to the small characteristic dimensions, enabling the synthesis of compounds that cannot be synthesized in conventional reactors. In the past years, efforts have been directed towards the application of microreactor technology for production purposes, especially in the pharmaceutical and fine chemicals industry. The challenge is how to get benefit of the transport rates inherent to microreactors while increasing the throughput for production applications. Two approaches to increase production rate are possible: a) scale-out by parallelization of units; b) scale-up by increase in channel size and flow rates. Scale-out would require thousands of units to achieve kg/min of production rates and development of very expensive and complex control systems to ensure identical operating conditions in each unit for a perfect and predictable overall reactor performance. On the other hand, scale-up by increase in channel size risks losing mass and heat transfer performance. The Advanced-Flow Reactor (AFR) manufactured by Corning Inc. combines both approaches being able to yield production rates of 10 - 300 g/min per module. If the AFR is demonstrated to perform efficiently and to be easily scalable, it may become an alternative for process intensification and transition from batch to continuous in the pharmaceutical and fine chemicals industry. Additional advantages include shorter process development times thanks to the scalability of the reactor modules, higher selectivities and yields, greener production processes, and possibility of introducing new chemistries. In this context, fundamental understanding of the hydrodynamics for multiphase systems is essential and critical for process development and scale-up purposes. The objective of this thesis is to study both experimentally and through computational fluid dynamic simulations the hydrodynamic characteristics of the AFR to demonstrate the capabilities of this technology using non-reactive (hexane/water) and reactive systems (carbon dioxide/water, ozone/alkene) at ambient conditions.
by María José Nieves Remacha.
Sc. D.
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Ani, Christian C. "Flow patterns, performance and scale-up of distillation trays". Thesis, Aston University, 1988. http://publications.aston.ac.uk/10234/.
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This work is concerned with the nature of liquid flow across industrial sieve trays operating in the spray, mixed, and the emulsified flow regimes. In order to overcome the practical difficulties of removing many samples from a commercial tray, the mass transfer process was investigated in an air water simulator column by heat transfer analogy. The temperature of the warm water was measured by many thermocouples as the water flowed across the single pass 1.2 m diameter sieve tray. The thermocouples were linked to a mini computer for the storage of the data. The temperature data were then transferred to a main frame computer to generate temperature profiles - analogous to concentration profiles. A comprehensive study of the existing tray efficiency models was carried out using computerised numerical solutions. The calculated results were compared with experimental results published by the Fractionation Research Incorporation (FRl) and the existing models did not show any agreement with the experimental results. Only the Porter and Lockett model showed a reasonable agreement with the experimental results for cenain tray efficiency values. A rectangular active section tray was constructed and tested to establish the channelling effect and the result of its effect on circular tray designs. The developed flow patterns showed predominantly flat profiles and some indication of significant liquid flow through the central region of the tray. This comfirms that the rectangular tray configuration might not be a satisfactory solution for liquid maldistribution on sieve trays. For a typical industrial tray the flow of liquid as it crosses the tray from the inlet to the outlet weir could be affected by the mixing of liquid by the eddy, momentum and the weir shape in the axial or the transverse direction or both. Conventional U-shape profiles were developed when the operating conditions were such that the froth dispersion was in the mixed regime, with good liquid temperature distribution while in the spray regime. For the 12.5 mm hole diameter tray the constant temperature profiles were found to be in the axial direction while in the spray regime and in the transverse direction for the 4.5 mm hole tray. It was observed that the extent of the liquid stagnant zones at the sides of the tray depended on the tray hole diameter and was larger for the 4.5 mm hole tray. The liquid hold-up results show a high liquid hold-up at the areas of the tray with low liquid temperatures, this supports the doubts about the assumptions of constant point efficiency across an operating tray. Liquid flow over the outlet weir showed more liquid flow at the centre of the tray at high liquid loading with low liquid flow at both ends of the weir. The calculated results of the point and tray efficiency model showed a general increase in the calculated point and tray efficiencies with an increase in the weir loading, as the flow regime changed from the spray to the mixed regime the point and the tray efficiencies increased from approximately 30 to 80%.Through the mixed flow regime the efficiencies were found to remain fairly constant, and as the operating conditions were changed to maintain an emulsified flow regime there was a decrease in the resulting efficiencies. The results of the estimated coefficient of mixing for the small and large hole diameter trays show that the extent of liquid mixing on an operating tray generally increased with increasing capacity factor, but decreased with increasing weir loads. This demonstrates that above certain weir loads, the effect of eddy diffusion mechanism on the process of liquid mixing on an operating tray to be negligible.
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Foster, Kennith E., N. Gene Wright y Susan Fitzgerald Fansler. "Guayule Natural Rubber Commercialization: A Scale-Up Feasibility Study". Office of Arid Lands Studies, University of Arizona (Tucson, AZ), 1991. http://hdl.handle.net/10150/303352.
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Conducted under USDA Agreement No. 58-3159-7-11 Guayule Natural Rubber ProgramIntroduction: The United States imports 100 percent of its natural rubber. Ninety-two percent of our natural rubber production is concentrated in Southeast Asia, which is subject to interruptions through political action or direct military intervention. Natural rubber, a critical and strategic material, is necessary in such articles as aircraft and ground vehicle tires, medical supplies, resilient mounts, and certain acoustical applications. Synthetic elastomers cannot meet performance requirements in these areas. A domestic source of natural rubber will assist in assuring a supply of this critical material for industry and defense. The U.S. Department of Defense (DoD) and the U.S. Department of Agriculture (USDA) signed a Master Memorandum of Understanding in 1982 that calls for cooperation with respect to food, agriculture, forestry, nutrition, and other research of mutual interest. With this MOU both agencies adopted a supplemental agreement in 1986 that initiated the Joint Guayule Domestic Rubber Program, whose ultimate goal is to promote an economically viable domestic guayule rubber industry. To accomplish this goal, both agencies have provided funding to plant and cultivate guayule shrubs, construct a 150 -long- ton -per -year prototype plant to extract rubber from the shrubs, and conduct evaluations to establish the performance capability of military products fabricated with domestic guayule rubber. A critical component of the supplemental agreement calls for the USDA to assess the feasibility of a commercial guayule rubber processing facility of 50,000-long-ton-per-year nameplace capacity. This report, based on the best available data (1990) and on assumptions of future advancements in technology (for 1996), is designed to address the commercial prospects for the establishment of a domestic guayule rubber industry. It also examines the feasibility and factors involved in meeting either 20 percent or 100 percent of the natural rubber needs of the U.S. Department of Defense in both peacetime and national emergency conditions.
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Khadem, Hamedani Behnam. "Design, Scale-up and Optimization of Double Emulsion Processes". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1097/document.
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De nos jours, les émulsions doubles se trouvent dans de nombreuses applications dans différents domaines, tels que le domaine alimentaire, les produits cosmétiques, les produits chimiques ou biochimiques. Dans les produits alimentaires par exemple, les émulsions doubles peuvent permettre d’encapsuler des arômes ou de réduire la teneur en matières grasses. La littérature manque cependant de compréhension globale de ces systèmes. La modélisation peut améliorer la compréhension d'un système et permettre d'optimiser les conditions de fonctionnement afin d'améliorer la qualité du produit. Dans ces systèmes, la qualité du produit est déterminée par l'efficacité de l'encapsulation et la distribution de la taille des gouttes internes et externes, qui peuvent affecter la stabilité physique pendant le stockage. L'objectif de ce travail est de réaliser une étude théorique et expérimentale approfondie des phénomènes intervenant à la fois lors de la préparation et du stockage des émulsions doubles. La contribution du travail peut donc être divisée en deux parties. Dans un premier temps, nous étudions les paramètres affectant l’étape de préparation des émulsions doubles et nous proposons des modèles pour les décrire. Trois procédés ont été considérés pour l’émulsification des émulsions doubles, l’ultra-sonication, l’Ultra-Turrax et un réacteur agité. Le modèle est basé sur un modèle de bilan de population des gouttelettes externes, incluant les phénomènes de rupture et de coalescence, associé à un modèle de relargage des gouttes internes. Le relargage des gouttes internes est supposé être régi par la rupture des gouttes externes. Pour être applicables aux différents procédés, les modèles de rupture ont été adaptés aux différentes échelles de turbulence, de dissipation pour ultra-sonication et inertielle pour Ultra-Turrax. La deuxième contribution de ce travail concerne l’étude des phénomènes ayant lieu lors du stockage des émulsions doubles, notamment le gonflement et le relargage des gouttes. Dans ce cas, deux modèles de bilan de population des gouttelettes internes et externes ont été développés, comprenant les phénomènes de gonflement des gouttelettes internes, et donc externes, ainsi que le relagage des gouttelettes internes par diffusion et coalescence avec la phase continue externe. Le modèle de gonflement prend en compte la pression de Laplace qui contrebalance le gradient de pression osmotique et arrête le gonflement. Dans les différentes étapes de préparation ou de stockage, les modèles développés permettent de prédire les distributions de la taille des gouttelettes et le taux de libérationDouble emulsions can nowadays be found in a number of applications in different domains, like food, cosmetics, chemicals or biochemical. In food for instance, double emulsions may allow to encapsulate flavors or reduce the fat content. Yet, the literature is still lacking a comprehensive understanding of these systems. Modelling may improve the understanding of a system and allow optimizing the operating conditions in order to improve the product quality. In these systems, the product quality is determined by the encapsulation efficiency and the inner and outer droplet size distribution, which may affect the physical stability during storage. The objective of this work is to handle theoretical and experimental investigations of the phenomena occurring during both the preparation and the storage of double emulsions. The contribution of the work can therefore be divided into two parts. First of all, investigations of the parameters affecting the preparation step of double emulsions are handled, and models are proposed to describe them. Three processes were considered for the emulsification of the double emulsions, ultrasonication, Ultra-Turrax and a stirred vessel. The model is based on a population balance model of the outer droplets, including the kernels of breakage and coalescence combined with a leakage model of the inner droplets. The leakage of inner droplets is assumed to be governed by the breakage of the outer droplets. In order to be applicable in the different processes, the breakage models were adapted to different scales of turbulence, the dissipation subrange for ultrasonication and the inertial subrange for the Ultra-Turrax. The second contribution of the work concerns the investigation of the phenomena taking place during the storage of the double emulsions, including swelling and release. In this case, two population balance models of the inner and outer droplets were considered, including the phenomena of swelling of the inner, and so of the outer, droplets as well as the escape of the inner droplets by diffusion and coalescence with the external continuous phase. The swelling model takes into account the Laplace pressure that counterbalances the osmotic pressure which is the driving force for swelling. In the different steps of preparation or storage, the developed models allow the prediction of the droplet size distributions and the release rate
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Cavinato, Mauro. "High shear wet granulation: process understanding and scale up". Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3427414.
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Among all the powder agglomeration processes, high shear wet granulation is one of the most commonly used techniques. It consists of the agglomeration of different powders through the addition of a granulating fluid and a vigorous mixing. Industries often turn to high shear granulation mainly to avoid segregation of critical components in a powder mixture, improve flowability and compactibility. Despite the great importance of this technique in many industrial activities, it is not totally clear how changes in the initial powder mixture or in process variables can affect the final product properties. Moreover, scale-up of high shear granulators is still difficult to perform.
The present research mainly focuses on the high shear wet granulation of pharmaceutical powders. Particularly, this research aims at closing the gap in understanding the role of primary particle properties (e.g. composition, primary particle size distribution) and process parameters (e.g. mixing speed, liquid flow rate and amount) on the final granule characteristics. Scale-up effects on the powder flow patterns were investigated as well.Tra tutti i processi di agglomerazione di polveri, la granulazione ad elevato shear risulta essere una delle tecniche più usate. Questa tecnica consiste nell‘agglomerazione di diverse polveri dovuta all‘aggiunta di un liquido legante e a un mescolamento energico. La granulazione ad elevato shear è utilizzata principalmente per evitare la segregazione di componenti critici in una miscela di polveri, per migliorare la scorrevolezza e comprimibilità. Nonostante l‘importanza di questa tecnica in numerosi settori industriali, l‘effetto delle proprietà delle polveri e dei parametri di processo sul prodotto finale è ancora poco chiaro. Lo scale up dei granulatori ad elevato shear risulta inoltre ancora difficile da portare a termine. La presente ricerca riguarda la granulazione high shear di polveri farmaceutiche. Lo scopo della ricerca è approfondire la conoscenza sul ruolo delle proprietà delle particelle nella miscela iniziale (p.e. composizione e distribuzione granulometrica) e parametri di processo (p.e. velocità di agitazione, portata e quantità di liquido) nel determinare le caratteristiche del prodotto finale. È stato inoltre analizzato l‘effetto dello scale up sul regime di mescolamento.
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Daniel, Michael John. "HPGR model verificatioin and scale-up / by Michael John Daniel". St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17397.pdf.
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Dell'Ava, Peter Mario Dell'Ava P. M. "Die produkteverteilung einer mischungsmaskierten Reaktion beim Scale-up von Rührkesseln /". [S.l.] : [s.n.], 1985. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=7810.
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Prasanna, Praveen Ram Menta. "A study and scale-up of desalination via membrane distillation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0023/MQ50653.pdf.
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Baten, Jasper Martijn van. "CFD: a design and scale-up tool for multiphase reactors". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2000. http://dare.uva.nl/document/55357.
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Glover, Richard D. "Permanganate passivation of pyrite containing ores scale up and characterization /". abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1446427.
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Davis, Van Leslie. "Characterization and scale-up of microbubble generation in column flotation". Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03242009-040658/.
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Chen, Zhiwei. "Hydrodynamics, stability and scale-up of slot-rectangular spouted beds". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/610.
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Slot-rectangular spouted beds, with rectangular cross-section and slotted gas inlets, have been proposed as a solution to overcoming scale-up difficulties with conventional axisymmetric spouted beds. They can be utilized in gas/particle processes such as drying of coarse particles and coating of tablets. However, application of this spouted bed was limited because of instability and insufficient hydrodynamic studies. The present work is therefore aimed at the study of hydrodynamics, stability and scale-up of slot-rectangular spouted beds.
The hydrodynamic study was carried out in four slot-rectangular columns of various width-to-thickness ratios combined with various slot configurations, particles of different properties and a range of operating conditions. Hydrodynamics of slot-rectangular spouted beds showed major similarity with conventional spouted beds. However, equations and mechanistic models adopted from conventional axisymmetric spouted beds generally failed to provide good predictions for the three-dimensional slot-rectangular geometry. New empirical correlations were derived for the minimum spouting velocity and maximum pressure drop for different slot configurations. Slot-rectangular spouted beds also showed more flow regimes than conventional spouted beds. Nine flow regimes, as well as unstable conditions, were identified based on frequency and statistical analysis of pressure fluctuations.
Slot geometrical configuration was found to be the main factor affecting the stability of slot-rectangular spouted beds. A comprehensive hydrodynamic study on the effect of slot configuration was therefore carried out. Slots of smaller length-to-width ratio, smaller length and greater depth were found to provide greater stability. Stable criteria for the slot configuration were found consistent with the conventional axisymmetric spouted beds with extra limitation on slot length-to-width ratio and slot depth. Local distributions of pressure, particle velocity and voidage, as well as spout shape and particle circulating flux, were compared for different slot configurations. Higher slot length-to-width ratios lead to slightly higher particle circulation rates.
A previously proposed scale-up method involving multiple chambers was tested in the present work using multiple slots. Instability caused by the merging of multiple spouts and asymmetric flow was successfully prevented by suspending vertical partitions between the fountains. Some criteria and guidelines were also proposed for scale-up using multiple chambers.
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Galmes, Meerhoff Carolina. "Novel aliphatic hyperbranched polyurethanes : synthesis, characterisation, scale-up and properties". Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420591.
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Ortega-Rivas, Enrique. "Dimensionless scale-up of hydrocyclones for separation of concentrated suspensions". Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253983.
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Zulqarnain, Kamran. "Scale-up of affinity separation based on magnetic support particles". Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313426.
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Gwele, Zuqaqambe. "Scale-up dynamics for the photocatalytic treatment of textile effluent". Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2761.
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Thesis (Masters of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, [2018].Enhancing the efficiency of large scale photocatalytic systems has been a concern for decades. Engineering design and modelling for the successful application of laboratory-scale techniques to large scale is obligatory. Among the many fields of research in heterogeneous photocatalysis, photocatalytic reaction engineering can initiate improvement and application of conservative equations for the design and scale-up of photocatalytic reactors. Various reactor configurations were considered, and the geometry of choice was the annular shape. Theory supports the view that annular geometry, in the presence of constant transport flow properties, monochromatic light, and an incompressible flow, will allow a system to respect the law of conservation of mass. The degradation of a simulated dye, methyl orange (MO), by titanium dioxide (TiO2) with a simulated solar light (halogen lamp) in a continuous recirculating batch photoreactor (CRBPR) was studied. A response surface methodology (RSM) based on central composite design (CCD) was applied to study interaction terms and individual terms and the role they play in the photocatalytic degradation of MO. The studied terms were volume (L), TiO2 (g), 2 (mL), and initial dye concentration (mg/L), to optimize these parameters and to obtain their mutual interaction during a photocatalytic process, a 24 full-factorial CCD and RSM with an alpha set to 1.5 were employed. The polynomial models obtained for the chosen responses (% degradation and reaction rate constant, k) were shown to have a good externally studentized vs normal percentage probability fit with R2 values of 0.69 and 0.77 respectively. The two responses had a common significant interaction term which was the H2O2 initial dye concentration term. The optimum degradation that was obtained in this study was a volume of 20 L, TiO2 of 10 g, H2O2 of 200 mL and the initial dye concentration of 5 mg/L which yielded 64.6% and a reaction rate constant of 0.0020 min-1. The model of percentage degradation was validated on a yield of 50% and 80% over a series of set volumes and the model validation was successful.
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Hall, Steven. "Scale-up of emulsification in in-line rotor–stator mixers". Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4045/.
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The power draw and emulsification performance of in-line rotor-stator mixers were investigated experimentally and theoretically, to predict droplet size as a function of process and formulation variables and to establish scale-up rules. The effect of process conditions, three mixer scales and thirteen rotor-stator geometry configurations on emulsification performance were investigated. Emulsions of a wide range of silicone oil viscosities of varying phase volumes, dispersed in aqueous surfactant and non-surfactant solutions were studied. For lab to factory scale in-line rotor-stator mixers, the most appropriate scaling parameter for mean drop size was tip speed at constant residence time for single and multiple passes. At a single scale, the stator open area was the rotor-stator geometry parameter which had the greatest effect on power draw and emulsification in turbulent flow. Mean drop size was a strong function of the rotor speed, dispersed phase viscosity, interfacial tension, and less dependent upon the mixer flow rate, continuous phase viscosity and dispersed phase volume fraction (for surfactant systems). Correlation of mean drop size with energy dissipation rate indicated that droplet break-up mainly depends on turbulent inertial stresses. Energy dissipation rate profiles were calculated theoretically using numerical simulations to calculate power draw and to solve population balance model equations. This is the first study in open literature where power consumption and drop size distributions in three scales of in-line rotor-stator mixer are reported.
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Pascoe, Jonathan Neil. "A study of scale-up methodologies for the filter cycle". Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/36023.
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This project was a joint venture between Loughborough University, the academic investigator, and ICI, the industrial sponsor. The aim was to develop and validate filter cycle scale-up methodologies, based on laboratory experiments at Loughborough and full-scale plant work at several ICI sites. Two ICI products, which experience processing problems during filtration, were chosen for assessment. They were a catalyst material (predominately iron oxide), processed by Synetix using rotary vacuum filters (RVFs), and titanium dioxide (TiO2) processed by Tioxide using a diaphragm filter press. A number of objectives were originally highlighted: (1) to develop and validate scale-up methodologies for a pressure filter and vacuum filter; (2) to develop models required to provide accurate predictions of filter performance; (3) to produce PC simulations of RVF and diaphragm filter press; (4) to produce reliable filter cycle data for process feeds of interest to ICI.
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Isaksson, Adam. "Evaluation of Scale-up Model for Flotation with Kristineberg Ore". Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70117.
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The objectives of this project were to survey the flotation circuit of the Boliden concentrator, mass balance collected data and evaluate a scale-up model for laboratory flotation results. The model assumes that half of the recovery to cleaner middlings in a standard laboratory test would report to the final concentrate if it were done in closed circuit, as is the case in a full-scale plant. It has been used by Boliden Mineral AB since 1982 but its accuracy had not been studied since 1986. The model can be categorised as of open circuit type with scale-up factors. The project was based on a complex Ag-Au-Cu-Pb-Zn sulphide ore from the Kristineberg mine. Laboratory tests were done to produce concentrates of CuPb, Cu, Pb and Zn with pulp samples from the concentrator as feed material. The software HSC 9.3 was used to mass balance data from the plant survey. It was decided that the model would be deemed usable if it was able to predict the plant results with the same accuracy as in the survey of 1986. A simulated locked cycle test with split factors (Agar & Kipkie, 1978) was identified as an alternative scale-up model. The results showed that the model was able to predict the plant results with the same accuracy as in 1986. It was especially good at predicting grade and recovery of the main element in a concentrate. For example, it predicted an 18 % higher grade and 11 % lower recovery of Cu to the CuPb concentrate, while a 3 % lower grade and 11 % lower recovery of Zn was predicted to the Zn concentrate. The locked cycle model gave much worse predictions on grades, but more accurate recoveries. It was also better at predicting the behaviour of minor impurity elements such as As and Bi. A recommendation is to combine the two alternatives in a type of "mixed cycle" model. In this study, it would have predicted an 18 % higher grade and 7 % lower recovery of Cu to the CuPb concentrate, as well as a 3 % lower grade and 1 % higher recovery of Zn to the Zn concentrate compared with plant results. Such a model seems to give better figures, but should be put to the test on more samples and ores to confirm this belief. It could at the very least be used to check the reliability of results predicted by the current scale-up model.Syftet med det här examensarbetet var att utföra en detaljprovtagning av flotationskretsen i Bolidens anrikningsverk, massbalansera data och sedan utvärdera en modell för uppskalning av resultat från laboratorieflotationer. Modellen antar att hälften av utbytet till returgodset i ett satsvis laboratorieförsök skulle rapportera till det slutliga koncentratet om det återcirkulerades, såsom i ett anrikningsverk. Den har använts av Boliden Mineral AB sedan 1982 men utvärderades senast 1986. Kategoriskt kan den ses som en uppskalningsmodell av typen öppen krets med skalfaktorer. Projektet baserades på en komplex Ag-Au-Cu-Pb-Zn sulfidmalm från gruvan i Kristineberg. Laboratorieförsök utfördes för att ta fram koncentrat av CuPb, Cu, Pb och Zn, med pulpprover från driften som utgångsmaterial. Programmet HSC 9.3 användes för att massbalansera datan från provtagningen. Det bestämdes att modellen skulle anses som godtagbar ifall den kunde förutspå driftresultatet med samma noggrannhet som 1986. Ett simulerat försök av typen sluten krets (Agar & Kipkie, 1978) identifierades som den mest intressanta alternativmodellen och även den utvärderades. Resultaten visade att modellen än idag ger godtagbara förutsägelser med samma noggrannhet som 1986. Modellen var särskilt bra på att förutspå halt och utbyte av den huvudsakliga metallen till dess eget koncentrat. Den förutspådde exempelvis en 18 % högre halt och 11 % lägre utbyte av Cu till CuPb-koncentratet, samt 3 % lägre halt och 11 % lägre utbyte av Zn till Zn-koncentratet. Den alternativa modellen gav sämre förutsägelser med avseende på halter, men bättre med avseende på utbyten. Den var bättre på att förutspå beteendet hos låghaltiga föroreningar såsom As och Bi. Rekommendationen är att kombinera de två modellerna till en "blandkretsmodell". I den här undersökningen hade ett sådant alternativ förutspått en 18 % högre halt och 7 % lägre utbyte av Cu till CuPb-koncentratet, samt 3 % lägre halt och 1 % högre utbyte av Zn till Zn-koncentratet jämfört med driftresultatet. En sådan modell tycks ge bättre förutsägelser, men bör testas på fler prover och malmtyper. Den borde åtminstone kunna användas för att kontrollera trovärdigheten hos resultaten förutspådda av den nuvarande modellen.
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Yeboue, Kouadio Yves. "Peptide Synthesis by Mechanochemistry : From Fundamental studies to Scale-Up". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS077.
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Compte tenu du durcissement des politiques environnementales vis-à-vis des polluants produits par l’industrie chimique et de la demande croissante de la part des consommateurs et des citoyens, il est impératif de trouver des méthodes alternatives aux procédés utilisant des quantités importantes de solvants et réactifs nocifs pour la santé et l’environnement. Les méthodes classiques de synthèse de peptides en font partie et nécessitent impérativement des améliorations. Ce manuscrit décrit les récents développements des procédés mécanochimiques en synthèse peptidique, procédés qui permettent un changement de paradigme par rapport aux procédés classiques utilisant des solvants. Ces procédés mécanochimiques sont utilisés au cours de cette thèse pour solutionner des problèmes d’épimérisation de peptides fréquemment rencontrés lors de l’emploi de la stratégie de couplage par fragment en solution. La preuve de faisabilité du couplage peptidique par ligation chimique native par broyage à billes a également été apportée au cours de cette thèse. L’approche de synthèse peptidique par mécanochimie a enfin été utilisée pour mettre au point des conditions efficaces permettant de monter en échelle la synthèse de peptides en utilisant le procédé d’extrusion réactive, ouvrant les portes à un transfert de la synthèse à l’échelle industrielle. L’ensemble de ces conditions mécanochimiques se sont avérées particulièrement efficaces quant à la synthèse de peptides avec des temps de réaction très faibles, d’excellents rendements, des taux d’épimérisation très faibles, un faible impact environnemental et une grande productivitéDue to the restriction of the environmental policies regarding the pollutants, it is urgent to find alternative methods to the processes that used large amount of highly toxic solvents and chemicals. Because of their negative environmental impact, conventional peptide synthesis methods require improvements. The use of mechanochemical processes allow to efficiently reduce the environmental impact by eliminating or replacing toxic solvents and chemicals. During this work, mechanochemical methods have been used to solve the peptide epimerization issues, frequently encountered during peptide fragment coupling strategy in solution. Additionally, by using these methods, peptide synthesis through native chemical ligation was also demonstrated. Furthermore, the use of the reactive extrusion process has enabled to efficiently work on large scale, thereby opening the boulevard to implement the peptide mechanosynthesis in industries. Finally, these methods have led to the desired peptides with noteworthy isolated yields, very short reaction times, low epimerization rate, low environmental impact and high productivity
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Salin, Irene. "Scale-up studies for thermo-oxidative stability of polymeric composites /". Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/9871.
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Yeh, Thomas M. "Syngas chemical looping particle production scale up and kinetics investigation /". Connect to resource, 2009. http://hdl.handle.net/1811/36976.
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Tuomaranta, J. (Jöns). "Resource allocation of high-growth firms in scale-up phase". Master's thesis, University of Oulu, 2019. http://jultika.oulu.fi/Record/nbnfioulu-201906052436.
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Abstract. High-growth firms are important for economic growth and employment points of view, which have been recognized by multiple studies. The purpose of this research is to gain new knowledge of the resource allocation of high-growth firms in general and especially during their scale-up phase. The specific interest of this research is how functional resources, research & development (R&D) and marketing & sales, are allocated within Finnish high-growth firms. The world-level reference for the marketing & sales and R&D investment levels are US high-growth firms. Therefore, US high-growth firms, prior to their initial public offering, are used as a reference to compare resource allocation during the scale-up phase.
The previous growth literature inclined to bundle all small and medium-sized enterprises (SMEs) together and to also make conclusions based on caracterisation of their different growth factors. Firms internal activities during the high-growth period has received less attention on the previous growth literature. The focus on Finnish studies has been on employment impact of high-growth firms. The high-growth firms resource allocation in scale-up phase is a scarcely studied research topic.
The marketing & sales expenses are not itemized within the commonly used profit and loss statement, i.e. layout of the profit and loss account by nature of expenses, by the firms in Finland. The exact comparison between US and Finnish firms’ financial statements is currently not possible, since the Finnish SMEs do not report their marketing & sales expenses. Hence the firms’ marketing & sales expense data is not publicly available, the topic has been investigated by conducting a web-based survey within Finnish high-growth firms’ top management and board members. As a result, the approach of a quantitative research method was chosen for this study.
This research contributes on the scarcely populated field of high-growth firms’ resource allocation studies. Firstly, for the firms, which are currently in the scale-up phase, there is clear contradictions between budgeted resource allocation and what the allocation should be based on the survey respondents’ opinion. The emphasis of resource allocation is still within R&D while it would need to be focused more to the marketing & sales, based on the results. Secondly, the assumption or expectation that most of the management and board members in Finnish high-growth firms seem to have regarding the required resourcing in the marketing & sales in the scale-up phase is inadequate, when compared to the US references. Thirdly, the board members would invest more to the marketing & sales during the scale-up phase than the operative management. The operative management would in average keep the R&D resourcing higher than marketing & sales in the scale-up phase. Additionally, venture capital and banks are in average almost as important a source for high-growth firms’ financing as founders are.
The contributions of the study can be used to guide high-growth firms’ managerial attention toward importance of resource allocation decisions. Moreover, policymakers and public actors can use the contributions when they are assessing firms receiving public funding to evaluate if there is adequate balance between R&D and marketing & sales investments.
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Stoker, Emily B. "Comparative Studies on Scale-Up Methods of Single-Use Bioreactors". DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/889.
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This study was performed to increase knowledge of oxygen mass transfer (kLa) and mixing times in the scale-up of disposable bioreactors.Results of oxygen mass transfer studies showed kLa to increase with increasing agitation and aeration rates. By maintaining a scale-up constant such as gassed power to volume or shear, an almost constant kLa was achieved during scale-up from 50 to 2000 L. Using the scale-up constant Pg/V resulted in statistically higher kLa values at greater reactor volumes. Mixing times were revealed to be significantly affected by agitation, but not by the aeration rates tested. No pattern was recognized in the mixing time data over an increase in volume.
Commonly used methods for predicting kLa upon scale-up were compared to experimental data. New coefficients were determined to fit the historic models to the parameters of this study, namely the unique geometry and low agitation and aeration rates used in the single-use systems. Each of the resulting four models was found to have average error rates from 16-23%. Although the error rates are not statistically different, the Moresi and Patete model was determined to be most conceptually accurate. The Moresi and Patete model found kLa to be more dependent on aeration than on the power input. This finding was consistent with the results of the experimental studies.
The results of this study were for aeration rates (0.02-0.04 vvm) and agitation rates (Pg/V range of 2-20 W/m3) that are commonly used in single-use bioreactor systems.