2022 |
Hoque MM, Doroodchi E, Jameson GJ, Evans GM, Mitra S, 'Numerical estimation of critical local energy dissipation rate for particle detachment from a bubble-particle aggregate captured within a confined vortex', Minerals Engineering, 180 (2022) [C1]
In flotation, interactions of bubble-particle aggregates with turbulent flow structures in the liquid medium result in particle detachment. This study aims to simulate this phenom... [more]
In flotation, interactions of bubble-particle aggregates with turbulent flow structures in the liquid medium result in particle detachment. This study aims to simulate this phenomenon involving a bubble-particle aggregate (bubble diameter ~ 3 mm and particle diameter ~ 314 µm) interacting with a turbulent flow structure manifested as a confined vortex in a square cavity connected to a square cross-section channel. An interface resolved three dimensional (3D) computational fluid dynamics (CFD) model was developed to quantify the bubble-vortex interaction dynamics over a range of channel Reynolds numbers. The CFD model produced a good agreement with the experimentally measured vorticity magnitude, local energy dissipation rate, and bubble motion. It was shown that a bubble-particle aggregate could be captured within the vortex by suitably varying the channel Reynolds number, eventually leading to particle detachment. A separate force balance analysis was performed to determine a criterion for particle detachment utilising the CFD model predicted vorticity and local energy dissipation rate. It was shown that a critical local energy dissipation rate ~ 1.59 m2/s3 was required for particle detachment to occur, which was also verified experimentally.
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Nova |
2020 |
Nguyen NN, Chu ATT, Sherman HM, Nguyen AV, Jameson GJ, 'A new paradigm of bubble-particle detachment interaction: How and where do the bubble and the particle detach?', Minerals Engineering, 159 (2020) [C1]
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Nova |
2020 |
Jameson GJ, Cooper L, Tang KK, Emer C, 'Flotation of coarse coal particles in a fluidized bed: The effect of clusters', Minerals Engineering, 146 (2020) [C1]
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Nova |
2019 |
Gautam S, Jameson GJ, 'The detachment of particles from bubbles at various locations in a turbulent flotation cell', Minerals Engineering, 132 316-325 (2019) [C1]
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Nova |
2019 |
Jameson GJ, Emer C, 'Coarse chalcopyrite recovery in a universal froth flotation machine', Minerals Engineering, 134 118-133 (2019) [C1]
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Nova |
2018 |
Ng WS, Cooper L, Connal LA, Forbes E, Jameson GJ, Franks GV, 'Tuneable collector/depressant behaviour of xanthate-functional temperature-responsive polymers in the flotation of copper sulfide: Effect of shear and temperature', MINERALS ENGINEERING, 117 91-99 (2018) [C1]
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Nova |
2017 |
Bournival G, Ata S, Jameson GJ, 'Bubble and Froth Stabilizing Agents in Froth Flotation', Mineral Processing and Extractive Metallurgy Review, 38 366-387 (2017) [C1]
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Nova |
2017 |
Wang G, Evans GM, Jameson GJ, 'Bubble movement in a rotating eddy: The implications for particle-bubble detachment', CHEMICAL ENGINEERING SCIENCE, 161 329-340 (2017) [C1]
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Nova |
2017 |
Wang G, Evans GM, Jameson GJ, 'Bubble-particle detachment in a turbulent vortex II-Computational methods', MINERALS ENGINEERING, 102 58-67 (2017) [C1]
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Nova |
2016 |
Wang G, Nguyen AV, Mitra S, Joshi JB, Jameson GJ, Evans GM, 'A review of the mechanisms and models of bubble-particle detachment in froth flotation', Separation and Purification Technology, 170 155-172 (2016) [C1]
Only when the process of particle detachment is well understood and modelled can minerals recovery using the flotation process be modulated to achieve a high efficiency by suitabl... [more]
Only when the process of particle detachment is well understood and modelled can minerals recovery using the flotation process be modulated to achieve a high efficiency by suitably changing the operating parameters. This is vitally necessary for the recovery of coarse particles in an energy efficient way, as detachment is the key limiting factor in the successful recovery of large particles. However, until the detachment mechanism is more fully understood, an upper limit on the floatable particle diameter still remains unidentified. To assess the current state of knowledge available in this area, a comprehensive literature review on the mechanisms and models of the bubble-particle detachment process in froth flotation is presented. In general, the detachment process is considered to be a stochastic process, and is usually attributed to the dynamic interactions with the turbulent flow structures (eddies) in the flotation environment which cause particles to detach because of dissipating energy. In this paper, previous studies on bubble-particle detachment have been critically analyzed with respect to the formulation of the models in predicting the detachment probability of particles. The models are classified into three different categories: force balance analysis; energy balance analysis and empirical analysis of particle size compared to maximum floatable particle size. Attention is also paid to an understanding of the mechanisms of bubble-particle detachment in quiescent and turbulent liquid flow fields. The predictions of all these models have been compared with the published experimental data and it was found that models which take an accurate consideration of the influence of eddies on a particle's detachment give the closest predictions. The generally held concept of bubble-particle detachment inside an eddy was experimentally validated, where a particle was observed to rotate on the surface of a bubble, resulting in a centrifugal acceleration 20 times that of gravitational acceleration. The aim of this paper is to review the developments and limitations of the existing models. The experimental work is reviewed so as to reveal the mechanisms of bubble-particle detachment. Therefore, the future development of models is identified in order to successfully predict particle detachment.
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Nova |
2016 |
Wang G, Evans GM, Jameson GJ, 'Experiments on the detachment of particles from bubbles in a turbulent vortex', Powder Technology, 302 196-206 (2016) [C1]
In this paper we present a new method for studying the detachment of particles from bubbles in a rotating turbulent eddy. The eddy is formed in a wall cavity in a two-dimensional ... [more]
In this paper we present a new method for studying the detachment of particles from bubbles in a rotating turbulent eddy. The eddy is formed in a wall cavity in a two-dimensional water tunnel with transparent walls. When water flows through the tunnel, a vortical flow field develops in the cavity. The properties of the eddy can be modulated by changing the free-stream velocity of the water in the tunnel. Bubbles are pre-loaded with one or more particles in a fluidized bed flotation device located beneath the vortex cavity. Loaded bubbles are released one at a time into the cavity, and the motion of the bubble-particle aggregate is studied using a high-speed video camera. The diameters of the particles and the bubbles, and the number of particles initially attached to the bubble, can be varied. The trajectories taken by the bubbles are quite complicated. In some cases, the bubble moves to the centre of the eddy, and particles rotate around its axis. If the rotational speed is sufficient, particles may detach due to centrifugal force. However, other modes were observed, including inertial detachment due to rapid changes in direction of the surface of the bubble, because of changes in trajectory of the bubble as a whole, or because of pulsations and oscillations of the bubble surface. Clusters of bubbles held together by particles were seen to form and reform. In the traditional explanation for the detachment of particles in flotation cells, it is assumed that particles detach from bubbles rotating in an eddy due to centrifugal force (Schulze, 1977) [1]. Although the conditions assumed in Schulze's theory may exist, it is only one of a range of phenomena that can lead to the detachment of particles from bubbles in a turbulent vortex. The interactions between bubbles and particles is stochastic in nature, and it is impossible to model precisely the series of events that take place when a particle and a bubble make contact with each other and move through the liquid. There can be no simple model for the recovery of hydrophobic particles in flotation machines.
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Nova |
2016 |
Wang G, Evans GM, Jameson GJ, 'Bubble-particle detachment in a turbulent vortex I: Experimental', MINERALS ENGINEERING, 92 196-207 (2016) [C1]
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Nova |
2015 |
Chen Z, Ata S, Jameson GJ, 'Break-up of bubble clusters in turbulent flow-Theory', Powder Technology, 279 228-232 (2015) [C1]
The behaviour of bubble clusters in turbulent conditions has been studied theoretically. The cluster behaviour was modelled based on concept drawn from the related field of bubble... [more]
The behaviour of bubble clusters in turbulent conditions has been studied theoretically. The cluster behaviour was modelled based on concept drawn from the related field of bubble breakup. It was assumed that the bubbles were bridged by particles, so the cohesive strength was determined by the capillary force between the bubbles and the particles. Two different theories were investigated for the disruptive force from the turbulent liquid: the shear rate hypothesis of Camp and Stein (1943), and the turbulent fluctuation model arising from Kolmogorov's theory of isotropic turbulence (Kolmogorov, 1941). It was found that neither method is applicable in the fragmentation stage. However, in the equilibrium stage, an equation derived from Camp and Stein's theory was more realistic than that obtained using Kolmogorov's equation.
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Nova |
2015 |
Jameson G, 'Back to basics: Getting physical', TCE The Chemical Engineer, 44-47 (2015) [C3] |
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2015 |
Chen Z, Ata S, Jameson GJ, 'Behaviour of bubble clusters in a turbulent flotation cell', Powder Technology, 269 337-344 (2015) [C1]
The rate of capture of particles decreases as the particle size increases in froth flotation. It has been postulated that the upper size range of particles that can be recovered i... [more]
The rate of capture of particles decreases as the particle size increases in froth flotation. It has been postulated that the upper size range of particles that can be recovered in conventional machines could be extended by the use of bubble clusters [1].This study is concerned with the behaviour of bubble clusters in turbulent flotation cell. The breakup and re-formation of clusters and the effect of bubble size and impeller speed on the behaviour of clusters have been investigated. The apparatus used was essentially a laboratory flotation cell, agitated by a Rushton turbine. The cell was modified to allow pre-formed clusters to rise out of a fluidized bed and into the path of the rotating impeller. The events were captured using a digital camera, and the images were analysed to give the sizes of the bubbles and clusters.In the first part of the investigation, a collector was used but no frother. Under these conditions, the bubble diameter was effectively controlled by the collector concentration, and it varied considerably. It was found that the sizes of clusters decrease with increasing shear rate at low impeller speeds, and at higher speeds the clusters are broken up into bubbles and particles.In the second part, frother was used at a concentration above the critical coalescence concentration, to control the bubble size, which remained essentially constant at this concentration. The bubbles were too small to be broken by the action of the impeller, so they always remained at the same size. In this case it was found that when the impeller speed was increased, two stages of formation were observed, the fragmentation and equilibrium stages. In the fragmentation stage, at low impeller speeds, the clusters were loose and filamentous, and as the energy input increases, they rupture and re-form. In the second stage, above a critical impeller speed, dense clusters formed whose size was relatively insensitive to the energy input.
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Nova |
2015 |
Rahman RM, Ata S, Jameson GJ, 'Study of froth behaviour in a controlled plant environment - Part 1: Effect of air flow rate and froth depth', Minerals Engineering, 81 152-160 (2015) [C1]
This paper presents the results of a thorough investigation into the froth recovery measurements in a controlled plant environment using a device that allows direct collection of ... [more]
This paper presents the results of a thorough investigation into the froth recovery measurements in a controlled plant environment using a device that allows direct collection of dropback particles from the froth phase. Experiments were performed at the Northparkes concentrator (NSW, Australia), using a feed taken from the head of the cleaner scavenger bank. The feed slurry had a relatively higher copper grade varying from 5.2% to 6.8%. Experiments were performed to investigate the effect of important flotation parameters such as air flow rate and froth depth, on the froth performance. The size of the particles in the relevant streams was analysed to acquire in-depth knowledge about the froth dropback mechanism. The results suggested that the froth recovery could be as low as 70%, although it was relatively easy to achieve the values in the range 75-85% by the correct choice of operating variables. It was found that the air flow rate has a positive impact on both collection (pulp) and froth zone recoveries. However, the effect was more prominent in the froth zone. It appeared that the froth recovery is a strong function of particle size.
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Nova |
2015 |
Rahman RM, Ata S, Jameson GJ, 'Study of froth behaviour in a controlled plant environment - Part 2: Effect of collector and frother concentration', Minerals Engineering, 81 161-166 (2015) [C1]
An investigation into froth zone recovery in a controlled plant environment is presented. The effect of operating conditions on the froth performance is given in our previous work... [more]
An investigation into froth zone recovery in a controlled plant environment is presented. The effect of operating conditions on the froth performance is given in our previous work (Rahman et al., 2015). This paper is primarily concerned with the influence of chemical properties such as frother and collector concentration on the froth behaviour. The results suggested that increasing the collector concentration gave expected results in the collection (pulp) zone, with a significant increase in coarse particle recovery. However, at high collector concentrations, it was observed that there was an increase in bubble coalescence and froth instability as well as a slight decrease in froth recovery. Increasing frother concentration gave a significant improvement in froth recovery and a slight increase in the collection zone recovery was also found. This was attributed to the formation of finer, more stable, bubbles and a corresponding increase in froth stability. Size and grade analysis of the samples suggested that the dropback particles were mainly composite or middling fractions. It appeared that particles whose grade was higher than the feed may be collected into the froth zone, but some particles with grades lower than the concentrate may detach from the froth.
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Nova |
2015 |
Chen Z, Ata S, Jameson GJ, 'Breakup and re-formation of bubble clusters in a flotation cell', Minerals Engineering, 71 16-20 (2015) [C1]
This study is concerned with the behavior of bubble clusters in a well-controlled turbulent flow. We used a specially designed cell where the bubble aggregates could be formed and... [more]
This study is concerned with the behavior of bubble clusters in a well-controlled turbulent flow. We used a specially designed cell where the bubble aggregates could be formed and exposed to breakage by a rotating impeller. The effects of impeller speed and the concentration of collector on cluster behavior were studied. It was found that the size of the clusters increases with the concentration of collector used. We also found that although the clusters could easily be destroyed under the action of impeller, they could reform, especially at lower impeller speeds. It was observed that the size of the bubbles arriving into the impeller region in the absence of particles before breakage was considerably higher than the size of the clusters formed at the same impeller speed. It appears that both cluster breakage and re-formation take place simultaneously, and the extent of formation and regrowth is mainly determined by the hydrophobicity of the particles and the impeller speed.
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Nova |
2014 |
Bournival G, Du Z, Ata S, Jameson GJ, 'Foaming and gas dispersion properties of non-ionic frothers in the presence of hydrophobized submicron particles', INTERNATIONAL JOURNAL OF MINERAL PROCESSING, 133 123-131 (2014) [C1]
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Nova |
2014 |
Wang G, Zhou S, Joshi JB, Jameson GJ, Evans GM, 'An energy model on particle detachment in the turbulent field', Minerals Engineering, 69 165-169 (2014) [C1]
A flotation detachment model is developed by considering energy balance in the process. Energies concerned are surface energy increment and kinetic energy supplied by turbulent li... [more]
A flotation detachment model is developed by considering energy balance in the process. Energies concerned are surface energy increment and kinetic energy supplied by turbulent liquid motion. Surface energy increment is the work of adhesion by surface forces which is reflected by surface tension and contact angle. What makes this model outstanding from other detachment models of energy balance perspective is more accurate account of kinetic energy supplied from turbulent liquid motion. Eddies in the same scale as attached particles are considered accountable for particle detachment in the close vicinity. In this way, detachment probability is written as a function of energy dissipation rate. Predictions from different models are compared to experimental results. It is demonstrated that previous models overestimate the influence from turbulent liquid motion. Notably, with more accurate account of eddies' influence, the new model predicts particle detachment in accordance with experimental results.
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Nova |
2014 |
Bournival G, Ata S, Jameson GJ, 'The influence of submicron particles and salt on the recovery of coarse particles', Minerals Engineering, 69 146-153 (2014) [C1]
Coarse particles are more difficult to float. One of the factors that contributes to poor floatability is the stability of froth. The froth formed in industrial flotation cells is... [more]
Coarse particles are more difficult to float. One of the factors that contributes to poor floatability is the stability of froth. The froth formed in industrial flotation cells is typically not strong enough to provide adequate support for coarse and dense particles. The present study investigates how the presence of hydrophobic submicron particles at low concentration increases the recovery of relatively coarse particles through improvement in the froth stability. Silica particles with d80 of approximately 230 µm were floated in a laboratory mechanical flotation cell in a collector-free environment in the presence of poly(propylene glycol) 425 as a frothing agent. The hydrophobicity of the feed particles was modified through an esterification process with different alcohols ranging from 3 to 8 hydrocarbon groups to form a coating of intermediate hydrophobicity. Hydrophobised silica submicron particles of 300 nm in size were added to the flotation cell at 0.01 and 0.1 wt% concentration. The effect of electrolyte, sodium chloride, in the concentration range 10-5-10-1 M on the recovery of coarse particles was also investigated. For the feed employed, 1-butanol was found to provide relatively good flotation properties with a possibility for improvement by stabilising the froth phase. Both additives slightly stabilised the froth phase, which resulted in an increase in the maximum recovery of up to approximately 8%. It appeared that the additives had no significant effect on the first-order flotation rate constant.
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Nova |
2014 |
Wang G, Sathe M, Mitra S, Jameson GJ, Evans GM, 'Detachment of a bubble anchored to a vertical cylindrical surface in quiescent liquid and grid generated turbulence', Canadian Journal of Chemical Engineering, 92 2067-2077 (2014) [C1]
Turbulence plays a critical role in detachment process of bubble from a solid surface. To investigate this effect, detachment process of a stationary air bubble from a nozzle in b... [more]
Turbulence plays a critical role in detachment process of bubble from a solid surface. To investigate this effect, detachment process of a stationary air bubble from a nozzle in both quiescent and turbulent liquid field was studied. A stationary vertical (flat-ended) needle of ID 1.24mm was used as a nozzle to generate a bubble which was anchored to the needle tip. Different sizes of bubbles were generated in quiescent liquid. Volume and contact angle for these bubbles were measured precisely using microscopic imaging technique and correlated. In the quiescent case experiments, a constant contact angle of 90° and bubble diameter of 3.05±0.004mm were obtained consistently. A simple force balance approach was proposed assuming bubble in equilibrium to determine this maximum bubble diameter during detachment. The detached bubble size calculated using this approach agreed fairly well with the experimental results. An oscillating grid device capable of operating at different frequencies was then applied to generate a homogeneous, near-isotropic turbulent velocity field around the anchored bubble. It was observed that for detachment of smaller bubbles, higher turbulence intensity was indeed necessary. The turbulent flow field was quantified using particle image velocimetry (PIV) technique and resolved into flow structures (eddies) of different length scales using a Gaussian filter. It was concluded that smaller eddies perturbed the bubble interface whilst the larger eddies contributed to weakening of the capillary force causing the bubble detachment. Energy dissipation profile obtained from the PIV images indicated significant energy dissipation near the bubble compared to the bulk fluid which supported the fact that strong interactions between bubble and eddies were indeed responsible for bubble detachment.
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Nova |
2014 |
Bournival G, Ata S, Karakashev SI, Jameson GJ, 'An investigation of bubble coalescence and post-rupture oscillation in non-ionic surfactant solutions using high-speed cinematography', JOURNAL OF COLLOID AND INTERFACE SCIENCE, 414 50-58 (2014) [C1]
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Nova |
2014 |
Ireland PM, Jameson GJ, 'Collision of a rising bubble-particle aggregate with a gas-liquid interface', International Journal of Mineral Processing, 130 1-7 (2014) [C1]
In this paper we investigate the hypothesis that when bubbles carrying attached hydrophobic particles arrive at an air-liquid interface, the abrupt change in velocity is sufficien... [more]
In this paper we investigate the hypothesis that when bubbles carrying attached hydrophobic particles arrive at an air-liquid interface, the abrupt change in velocity is sufficient to dislodge attached particles, which fall back into the liquid. For the first time, experiments have demonstrated a case in which the particles do not detach, but move smoothly over the surface of the bubbles. The kinetic energy of arrival is dissipated by the motion of the particles through the liquid, as they move over the surface of the bubble while remaining attached. Some energy is also dissipated by the pulsations of the bubbles. The pulsations themselves do not lead to detachment of particles. A theory has been developed to explain the observed phenomena. © 2014 Published by Elsevier B.V.
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Nova |
2014 |
Curry JA, Ismay MJL, Jameson GJ, 'Mine operating costs and the potential impacts of energy and grinding', Minerals Engineering, 56 70-80 (2014) [C1]
An understanding of the breakdown of mine costs is an important tool for researchers and developers who seek to place novel cost-reducing unit operations in the wider general cost... [more]
An understanding of the breakdown of mine costs is an important tool for researchers and developers who seek to place novel cost-reducing unit operations in the wider general cost context. This paper provides a breakdown of operating costs in 63 mines by dividing them into three main categories: mining, milling, and general and administrative (G & A) costs. The study looks at patterns in mining type, mill processing type, mineral type, and the differences between costs expressed in feasibility studies vs. operating mines. The paper explores the reasons for the relationships observed and then presents a total average mine cost breakdown. It was found that the mean relative mining and milling costs did not differ significantly, and that on average they had equal shares of the total enterprise operating costs. Effects of mine and mineral type were observed, with underground milling costs being significantly less than open pit milling costs and gold mines occupying a significantly larger share of mine operating costs than copper-containing mines. The overall relative operating costs were found to be in the ratios between (43:43:14) and (45:45:10) (Mine:Mill:G & A). A treatment of potential unit operations and innovative technologies is provided at the conclusion of the paper, including coarse particle recovery by flotation and novel grinding technologies. © 2013 Published by Elsevier Ltd.
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Nova |
2014 |
Bournival G, Du Z, Ata S, Jameson GJ, 'Foaming and gas dispersion properties of non-ionic surfactants in the presence of an inorganic electrolyte', Chemical Engineering Science, 116 536-546 (2014) [C1]
Foams represent an important area of research due to their relevance in many industrial processes. Where there are geographical constraints, which can limit access to fresh water,... [more]
Foams represent an important area of research due to their relevance in many industrial processes. Where there are geographical constraints, which can limit access to fresh water, there is an economic incentive in using recycled water, bore water and even seawater for industrial purposes. This creates a growing interest in determining the effect of inorganic electrolytes on foaming and gas dispersion properties of non-ionic surfactant solutions. The present study compares the foaming and gas dispersion properties of the non-ionic surfactants 1-pentanol, tri(propylene glycol) methyl ether, and poly(propylene glycol) 425. For all surfactants, the stabilisation mechanism was influenced by the concentration of surfactant and the presence of salt with PPG being affected to a lesser extent. Sodium chloride was observed to have a detrimental effect on foaming at higher surfactant concentrations but improved foaming at low surfactant concentrations. At low surfactant concentrations, the addition of salt improved foaminess by dampening the hydrophobic force. An increase in gas holdup with increasing surfactant concentration was observed and was attributed to a decrease in bubble size. For poly(propylene glycol) an initial decrease in gas holdup was observed at very low concentrations. Salt mainly affected gas dispersion properties at a higher concentration. © 2014 Elsevier Ltd.
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Nova |
2013 |
Ireland PM, Jameson GJ, 'Particle dynamics in cyclone tribochargers', JOURNAL OF ELECTROSTATICS, 71 449-455 (2013) [C1]
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Nova |
2013 |
Ata S, Jameson GJ, 'Recovery of coarse particles in the froth phase - A case study', MINERALS ENGINEERING, 45 121-127 (2013) [C3]
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2012 |
Neville FC, Mohd Zin AB, Jameson GJ, Wanless EJ, 'Preparation and characterization of colloidal silica particles under mild conditions', Journal of Chemical Education, 89 940-942 (2012) [C1]
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Nova |
2012 |
Ireland PM, Jameson GJ, 'Drag force on a spherical particle moving through a foam: The role of wettability', International Journal of Mineral Processing, 102-103 78-88 (2012) [C1]
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Nova |
2012 |
Rahman RM, Ata S, Jameson GJ, 'The effect of flotation variables on the recovery of different particle size fractions in the froth and the pulp', International Journal of Mineral Processing, 106 70-77 (2012) [C1]
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Nova |
2012 |
Jameson GJ, 'The effect of surface liberation and particle size on flotation rate constants', Minerals Engineering, 36-38 132-137 (2012) [C1]
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Nova |
2012 |
Gautam A, Jameson GJ, 'The capillary force between a bubble and a cubical particle', Minerals Engineering, 36-38 291-299 (2012) [C1]
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Nova |
2012 |
Goel S, Jameson GJ, 'Detachment of particles from bubbles in an agitated vessel', Minerals Engineering, 36-38 324-330 (2012) [C1]
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Nova |
2012 |
Moberg AK, Ellem GK, Jameson GJ, Herbertson JG, 'Simulated cell trajectories in a stratified gas-liquid flow tubular photobioreactor', Journal of Applied Phycology, 24 357-363 (2012) [C1]
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Nova |
2011 |
Ata S, Pugh RJ, Jameson GJ, 'The influence of interfacial ageing and temperature on the coalescence of oil droplets in water', Colloids and Surfaces A: Physicochemical and Engineering Aspects, 374 96-101 (2011) [C1]
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Nova |
2010 |
Jameson GJ, 'Advances in fine and coarse particle flotation', Canadian Metallurgical Quarterly, 49 328-330 (2010) [C1]
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Nova |
2010 |
Button EC, Davidson JF, Jameson GJ, Sader JE, 'Water bells formed on the underside of a horizontal plate. Part 2. Theory', Journal of Fluid Mechanics, 649 45-68 (2010) [C1]
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Nova |
2010 |
Jameson GJ, Jenkins CE, Button EC, Sader JE, 'Water bells formed on the underside of a horizontal plate. Part 1. Experimental investigation', Journal of Fluid Mechanics, 649 19-43 (2010) [C1]
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Nova |
2010 |
Jameson GJ, 'New directions in flotation machine design', Minerals Engineering, 23 835-841 (2010) [C1]
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Nova |
2009 |
Ireland PM, Jameson GJ, 'Foam slip on surfaces of intermediate or low wettability', Chemical Engineering Science, 64 3859-3867 (2009) [C1]
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Nova |
2009 |
Zhou Y, Yu H, Wanless EJ, Jameson GJ, Franks GV, 'Influence of polymer charge on the shear yield stress of silica aggregated with adsorbed cationic polymers', Journal of Colloid and Interface Science, 336 533-543 (2009) [C1]
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Nova |
2009 |
Hunter TN, Jameson GJ, Wanless EJ, Dupin D, Armes SP, 'Adsorption of submicrometer-sized cationic sterically stabilized polystyrene latex at the air-water interface: Contact angle determination by ellipsometry', Langmuir, 25 3440-3449 (2009) [C1]
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Nova |
2009 |
Hunter TN, Wanless EJ, Jameson GJ, 'Effect of esterically bonded agents on the monolayer structure and foamability of nano-silica', Colloids and Surfaces A: Physicochemical and Engineering Aspects, 334 181-190 (2009) [C1]
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Nova |
2009 |
Hunter TN, Wanless EJ, Jameson GJ, Pugh RJ, 'Non-ionic surfactant interactions with hydrophobic nanoparticles: Impact on foam stability', Colloids and Surfaces A: Physicochemical and Engineering Aspects, 347 81-89 (2009) [C1]
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Nova |
2008 |
Jameson GJ, Jenkins C, Button EC, Sader JE, 'Water bells created from below', Physics of Fluids, 20 091108 (2008) [C3] |
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Nova |
2008 |
Hunter TN, Pugh RJ, Franks GV, Jameson GJ, 'The role of particles in stabilising foams and emulsions', Advances in Colloid and Interface Science, 137 57-81 (2008) [C1]
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Nova |
2008 |
Olsen AH, Franks GV, Biggs S, Jameson GJ, 'Collision efficiency factor for heteroaggregation: Extension to soft interactions', Journal of Chemical Physics, 128 044913 (2008) [C1]
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Nova |
2008 |
Zhou Y, Gan Y, Wanless EJ, Jameson GJ, Franks GV, 'Interaction forces between silica surfaces in aqueous solutions of cationic polymeric flocculants: Effect of polymer charge', Langmuir, 24 10920-10928 (2008) [C1]
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Nova |
2008 |
Yates PD, Franks GV, Jameson GJ, 'Orthokinetic heteroaggregation with nanoparticles: Effect of particle size ratio on aggregate properties', Colloids and Surfaces A: Physicochemical and Engineering Aspects, 326 83-91 (2008) [C1]
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Nova |
2008 |
Zhou Y, Jameson GJ, Franks GV, 'Influence of polymer charge on the compressive yield stress of silica aggregated with adsorbed cationic polymers', Colloids and Surfaces A: Physicochemical and Engineering Aspects, 331 183-194 (2008) [C1]
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Nova |
2007 |
Ireland PM, Cunningham R, Jameson GJ, 'The behaviour of wash water injected into a froth', International Journal of Mineral Processing, 84 99-107 (2007) [C1]
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2007 |
Hunter TN, Jameson GJ, Wanless EJ, 'Determination of contact angles of nanosized silica particles by multi-angle single-wavelength ellipsometry', Australian Journal of Chemistry, 60 651-655 (2007) [C1]
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Nova |
2007 |
Ireland PM, Jameson GJ, 'Liquid transport in a coalescing froth', Canadian Journal of Chemical Engineering, 85 654-661 (2007) [C1]
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2007 |
Jameson GJ, Parekh VV, 'Effect of n-alcohols on the stability of bubbles', Canadian Metallurgical Quarterly, 46 311-320 (2007) [C1]
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2007 |
Ireland PM, Jameson GJ, 'Liquid transport in a multi-layer froth', Journal of Colloid and Interface Science, 314 207-213 (2007) [C1]
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Nova |
2007 |
Stevenson P, Jameson GJ, 'Modelling continuous foam fractionation with reflux', Chemical Engineering and Processing: Process Intensification, 46 1286-1291 (2007) [C1]
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2006 |
Olsen AH, Franks GV, Biggs S, Jameson GJ, 'An improved collision efficiency model for particle aggregation', Journal of Chemical Physics, 125 (2006) [C1]
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2006 |
Jameson GJ, 'Selected papers from the Centenary of Flotation Symposium, 5-9 June 2005, Brisbane, Australia - Foreword', MINERALS ENGINEERING, 19 529-530 (2006)
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2006 |
Nguyen AV, Alexandrova L, Grigorov L, Jameson GJ, 'Dewetting kinetics on silica substrates: Three phase contact expansion measurements for aqueous dodecylammonium chloride films', Minerals Engineering, 19 651-658 (2006) [C1]
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2006 |
Ata S, Pigram SM, Jameson GJ, 'Tracking of particles in the froth phase: An experimental technique', Minerals Engineering, 19 824-830 (2006) [C1]
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2006 |
Jameson GJ, 'Minerals Engineering: Foreword (editorial)', Minerals Engineering, 19 529-530 (2006) [C3] |
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2006 |
Jameson GJ, 'Selected papers from the Centenary of Flotation Symposium, 5-9 June 2005, Brisbane, Australia', Minerals Engineering, 19 340 (2006) [C2] |
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2006 |
Franks GV, Sepulveda CV, Jameson GJ, 'PH-sensitive flocculation: Settling rates and sediment densities', AICHE Journal, 52 2774-2782 (2006) [C1]
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2006 |
Nguyen AV, George PF, Jameson GJ, 'Demonstration of a minimum in the recovery of nanoparticles by flotation: Theory and experiment', Chemical Engineering Science, 61 2494-2509 (2006) [C1]
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Nova |
2005 |
Olsen AH, Franks GV, Biggs S, Jameson GJ, 'Bi-modal Hetro-aggregation Rate Response to Particle Dosage', Journal of Chemical Physics, 123 - (2005) [C1]
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Nova |
2005 |
Franks GV, Yates PD, Lambert NW, Jameson GJ, 'Aggregate size and density after shearing, implications for dewatering fine tailings with hydrocyclones', International Journal of Mineral Processing, 77 46-52 (2005) [C1]
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Nova |
2005 |
Nguyen AV, Jameson GJ, 'Sliding of fine particles on the slip surface of rising gas bubbles: Resistance of liquid shear flows', International Journal of Multiphase Flow, 31 492-513 (2005) [C1]
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2005 |
Ata S, Jameson GJ, 'The formation of bubble clusters in flotation cells', International Journal of Mineral Processing, 76 123-139 (2005) [C1]
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Nova |
2005 |
Harvey PA, Nguyen AV, Jameson GJ, Evans GM, 'Influence of sodium dodecyl sulphate and Dowfroth frothers on froth stability', Minerals Engineering, 18 311-315 (2005) [C1]
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Nova |
2005 |
Yates PD, Franks GV, Biggs S, Jameson GJ, 'Heteroaggregation with nanoparticles: effect of particle size ratio on optimum particle dose', Colloids and Surfaces a-Physicochemical and Engineering Aspects, 255 85-90 (2005) [C1]
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2005 |
Evans GM, Manning SA, Jameson GJ, 'Cavity formation, growth, and dispersion behind rotating impeller blades', Industrial & Engineering Chemistry Research, 44 6304-6309 (2005) [C1]
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Nova |
2005 |
Ata S, Pigram S, Jameson GJ, 'Tracking of particles in the froth phase - an experimental technique', Australasian Institute of Mining and Metallurgy Publication Series, 309-313 (2005)
This paper is concerned with the tracking of particles in the froth phase of an aerated water/glycerol mixture. Experiments have been carried out in a specially designed laborator... [more]
This paper is concerned with the tracking of particles in the froth phase of an aerated water/glycerol mixture. Experiments have been carried out in a specially designed laboratory flotation cell that allows formation of a deep froth. Phosphorescent tracer particles of various sizes were injected into the centre of a froth column where they were excited by ultraviolet lights, positioned at the back and front of the column. The motion of particles was captured on a digital camera with a green filter. The images from the digital camera were then transferred to a computer and an image analysis program was used to convert the colour intensity to the concentration of particles at each location within the froth. The tracer technique was used to determine the dispersion of hydrophilic particles and the variation of the concentration of solids with axial and radial positions.
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2005 |
Ata S, Agarwal A, Jameson GJ, 'The Formation of Bubble Clusters in Flotation Cells - Effect of Impeller Speed', Australasian Institute of Mining and Metallurgy Publication Series, 403-406 (2005)
This paper is concerned with the observation and analysis of bubble clusters in a laboratory flotation cell. A device was used in which bubbles were allowed to rise in clean water... [more]
This paper is concerned with the observation and analysis of bubble clusters in a laboratory flotation cell. A device was used in which bubbles were allowed to rise in clean water containing the same frother and collector concentration as in the cell. Bubble clusters were recorded using a high speed camera and analysed using an image analyser. Dodecyl amine was employed as a collector to float silica. The effect of impeller speed on the cluster behaviour was investigated. The results were interpreted in terms of cluster diameter and shape factor. The sizes of the bubbles forming the clusters were also measured and compared to the sizes of the independent bubbles in the cell. It was found that there was an optimum impeller speed in which the cluster diameter was a maximum. Higher agitation and the consequent higher power inputs resulted in cluster break-up while lower shear rates promoted cluster formation.
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2005 |
Alexandrova L, Nguyen AV, Grigorov L, Jameson GJ, 'Dewetting kinetics on silica substrates - three-phase contact expansion measurements for aqueous dodecylammonium chloride films', Australasian Institute of Mining and Metallurgy Publication Series, 397-402 (2005)
The dewetting kinetics between a small air-liquid interface and a silica (negatively charged in water) planar surface in solutions of dodecylammonium chloride (cationic surfactant... [more]
The dewetting kinetics between a small air-liquid interface and a silica (negatively charged in water) planar surface in solutions of dodecylammonium chloride (cationic surfactant) has been investigated using the Scheludko cell and digital high-speed video microscopy. The gas-liquid interface was created at the bottom of a small silica capillary of the cell and then was moved towards the silica planar surface. After the rupture of the liquid films between the interfaces, the expansion of the gas-liquid-solid three-phase contact (TPC) line was observed and recorded using a digital high-speed video microscope system, operating at 1000 frames per second. The surface tension of the surfactant solution was measured using the pendant drop technique. The equilibrium contact angle was measured using the Scheludko-Minings method with a silica micro-sphere. The TPC radius was determined as a function of time and compared against the available hydrodynamic and molecular-kinetic models. The experimental data are described very well by the molecular-kinetic model for the TPC line motion. The hydrodynamic model is in agreement with the experimental data only for a short time after inception of the three-phase contact expansion.
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2004 |
Yan Y, Jameson GJ, 'Application of the Jameson Cell technology for algae and phosphorus removal from maturation ponds', Int. Journal of Mineral Processing, 73 23-28 (2004) [C1]
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2004 |
Yan Y, Glover SM, Jameson GJ, Biggs SR, 'The flocculation efficiency of polydisperse polymer flocculants', Int. Journal of Mineral Processing, 73 161-175 (2004) [C1]
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2004 |
Glover SM, Yan Y, Jameson GJ, Biggs SR, 'Dewatering properties of dual-polymer-flocculated systems', Int. Journal of Mineral Processing, 73 145-160 (2004) [C1]
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2004 |
Ata S, Ahmed N, Jameson GJ, 'The effect of hydrophobicity on the drainage of gangue minerals in flotation froths', Minerals Engineering, 17 897-901 (2004) [C1]
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2004 |
George PF, Nguyen AV, Jameson GJ, 'Assessment of true flotation and entrainment in the flotation of submicron particles by fine bubbles', Minerals Engineering, 17 847-853 (2004) [C1]
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2004 |
Franks GV, Zhou Y, Yan Y, Jameson GJ, Biggs SR, 'Effect of aggregate size on sediment bed rheological properties', Physical Chemistry Chemical Physics, 6 4490-4498 (2004) [C1]
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Nova |
2003 |
Atkinson B, Jameson GJ, Nguyen AV, Evans GM, Machniewski PM, 'Bubble Breakup and Coalescence in a Plunging Liquid Jet bubble Column', The Canadian Journal of Chemical Engineering, 81 519-527 (2003) [C1]
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2003 |
Stevenson P, Sullivan SP, Jameson GJ, 'Short-time tracer dispersion in a two-dimensional rising froth', Chemical Engineering Science, 58 5025-5043 (2003) [C1]
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2003 |
Atkinson B, Jameson GJ, Nguyen AV, Evans GM, 'Increasing Gas - Liquid Contacting Using a Confined Plunging Liquid Jet', Journal of Chemical Technology and Biotechnology, 78 269-275 (2003) [C1]
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2003 |
Ata S, Ahmed N, Jameson GJ, 'A Study of bubble Coalescence in Flotation Froths', International Journal of Mineral Processing, 72 255-266 (2003) [C1]
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Nova |
2003 |
Phan MC, Nguyen AV, Miller JD, Evans GM, Jameson GJ, 'Investigations of Bubble-Particle Interactions', International Journal of Mineral Processing, 72 239-254 (2003) [C1]
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2003 |
Nguyen AV, Harvey PA, Jameson GJ, 'Influence of Gas Flow Rate and Frothers on Water Recovery in a Froth Column', Minerals Engineering, 16 1143-1147 (2003) [C1]
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2003 |
Stevenson P, Stevanov C, Jameson GJ, 'Liquid Overflow from a Column of Rising Aqueous Froth', Minerals Engineering, 16 1045-1053 (2003) [C1]
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2003 |
Burns JL, Yan Y, Jameson GJ, Biggs SR, 'The Rheology of Concentrated Suspensions of Depletion-Flocculated Latex Particles', Colloids and Surfaces A, 214 173-180 (2003) [C1]
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Nova |
2002 |
Burns JL, Yan Y, Jameson GJ, Biggs S, 'The effect of molecular weight of nonadsorbing polymer on the structure of depletion-induced flocs', Journal of Colloid and Interface Science, 247 24-32 (2002) [C1]
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Nova |
2002 |
Biggs SR, Burns JL, Yan Y, Jameson G, Jenkins P, 'Viscosity effect on the structural compactness of latex flocs formed under weak depletion attractions', Journal of Colloid and Interface Science, 255 91-97 (2002) [C1]
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2002 |
Ata S, Ahmed N, Jameson GJ, 'Collection of hydrophobic particles in the froth phase', International Journal of Mineral Processing, 64 101-122 (2002) [C1]
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Nova |
2002 |
Magrabi SA, Dlugogorski BZ, Jameson GJ, 'A comparative study of drainage characteristics in AFFF and FFFP compressed-air fire-fighting foams', Fire Safety Journal, 37 21-52 (2002) [C1]
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2001 |
Magrabi SA, Dlugogorski BZ, Jameson GJ, 'Free drainage in aqueous foams: model and experimental study', AIChE Journal, 47 No. 2 314-327 (2001) [C1]
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2000 |
Nguyen AV, Evans GM, Jameson GJ, 'Simple approximate expressions for electrical double-layer interaction at constant moderate potentials', Journal of Colloid and Interface Science, 230 205-209 (2000) [C1]
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2000 |
Gardiner BS, Dlugogorski BZ, Jameson GJ, 'Coarsening of two and three dimensional wet polydisperse foams', Phil. Mag. A, 80 (4) 981-1000 (2000) [C1]
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2000 |
Farmer AD, Collings AF, Jameson GJ, 'Effect of ultrasound on surface cleaning of silica particles', Int. J. Mineral Processing, 60 101-113 (2000) [C1]
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2000 |
Gardiner BS, Dlugogorski BZ, Jameson GJ, 'The steady shear of three-dimensional wet polydisperse foams', J. Non-Newt. Fluid Mech., 92 151-166 (2000) [C1]
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2000 |
Magrabi SA, Dlugogorski BZ, Jameson GJ, 'The performance of aged aqueous foams for mitigation of thermal radiation', Dev.Chem.Eng.Mineral Process, 8 93-112 (2000) [C1]
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2000 |
Biggs S, Habgood MG, Jameson GJ, Yan Y, 'Aggregate structures formed via a bridging flocculation mechanism', Chemical Engineering Journal, 80 13-22 (2000) [C1]
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2000 |
Glover SM, Yan Y, Jameson GJ, Biggs S, 'Bridging flocculation studied by light scattering and settling', Chemical Engineering Journal, 80 3-12 (2000) [C1]
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2000 |
Yan Y, Burns JL, Jameson GJ, Biggs S, 'The structure and strength of depletion-force induced particle aggregates', Chemical Engineering Journal, 80 23-30 (2000) [C1]
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2000 |
Biggs S, Burns JL, Yan Y, Jameson GJ, Jenkins P, 'Molecular weight dependence of the depletion interaction between silica surfaces in solutions of sodium poly(styrene sulfonate)', Langmuir, 16 9242-9248 (2000) [C1]
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2000 |
Nguyen AV, Evans GM, Jameson GJ, 'Erratum: Simple approximate expressions for electrical double-layer interaction at constant moderate potentials (Journal of Colloid and Interface Science (2000) 1:230 (205-209))', Journal of Colloid and Interface Science, 232 414 (2000)
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1999 |
Magrabi SA, Dlugogorski BZ, Jameson GJ, 'Bubble size distribution and coarsening of aqueous foams', Chemical Engineering Science, 54 4007-4022 (1999) [C1]
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1999 |
Gardiner BS, Dlugogorski BZ, Jameson GJ, 'Prediction of pressure losses in pipe flow of aqueous foams', Industrial & Engineering Chemistry Research, 38 1099-1106 (1999) [C1]
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1999 |
Bremmell KE, Jameson GJ, Biggs S, 'Adsorption of ionic surfactants in particulate systems: flotation, stability, and interaction forces', Colloids and Surfaces, 146 75-87 (1999) [C1]
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1999 |
Burns JL, Yan Y, Jameson GJ, Biggs S, 'Relationship between interaction forces and the structural compactness of depletion flocculated colloids', Colloids and Surfaces, 162 265-277 (1999) [C1]
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1999 |
Bremmell KE, Jameson GJ, Biggs S, 'Forces between surfaces in the presence of a cationic polyelectrolyte and an anionic surfactant', Colloids and Surfaces, 155 1-10 (1999) [C1]
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1999 |
Jameson GJ, 'Hydrophobicity and floc density in induced-air flotation for water treatment', Colloids and Surfaces A, 151 269-281 (1999) [C1]
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1999 |
Gardiner BS, Dlugogorski BZ, Jameson GJ, 'The evolution of defects in a two-dimensional wet foam', J.Phys:Condens.Matter, 11 5437-5453 (1999) [C1]
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1998 |
Gardiner BS, Dlugogorski BZ, Jameson GJ, 'Rheology of Fire-Fighting Foams', Fire Safety Journal, 31 61-75 (1998) [C1]
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1998 |
Gardiner BS, Dlugogorski BZ, Jameson GJ, Chhabra RP, 'Yield Stress Measurements of Aqueous Foams in the Dry Limit', J.Rheology, 42(6) 1437-1450 (1998) [C1]
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1998 |
Jones SFD, Galvin KP, Evans GM, Jameson GJ, 'Carbonated Water: The Physics of the Cycle of Bubble Production', Chemical Engineering Science, 53, No.1 169-173 (1998) [C3]
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1998 |
Bremmell KE, Jameson GJ, Biggs S, 'Polyelectrolyte Adsorption at the Solid/Liquid Interface Interaction Forces and Stability', Colloids and Surfaces, 139 199-211 (1998) [C1]
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1998 |
Jameson GJ, 'New Technology and Science in Flotation Separations', Current Opinion in Colloid & Interface Science, 3 351-359 (1998) [C1]
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1998 |
Burns JL, Yan Y, Jameson GJ, Biggs S, 'A Comparison of the Fractal Properties of Salt-Aggregated and Polymer-Flocculated Colloidal Particles', Progr Colloid Polymer Science, 110 70-75 (1998) [C1]
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1997 |
Burns JL, Yan YD, Jameson GJ, Biggs S, 'A light scattering study of the fractal aggregation behavior of a model colloidal system', LANGMUIR, 13 6413-6420 (1997)
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1996 |
Bremmell KE, Biggs SR, Jameson GJ, 'Adsorption behaviour of surfactants and cationic polyelectrolytes on silica.', ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 212 97-COLL (1996) |
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1993 |
MOHAMED P, JAMESON GJ, 'HYDRODYNAMICS OF A RADIAL JET INDUCTOR', CHEMICAL ENGINEERING SCIENCE, 48 489-501 (1993)
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1993 |
KUBOTA K, JAMESON GJ, 'A STUDY OF THE ELECTROPHORETIC MOBILITY OF A VERY SMALL INERT-GAS BUBBLE SUSPENDED IN AQUEOUS INORGANIC ELECTROLYTE AND CATIONIC SURFACTANT SOLUTIONS', JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, 26 7-12 (1993)
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1993 |
JAMESON GJ, 'BUBBLES IN MOTION', CHEMICAL ENGINEERING RESEARCH & DESIGN, 71 587-594 (1993)
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1992 |
Manning SA, Jameson GJ, 'A study of ventilated gas cavities on disc-turbine blades (1992)
In this study, air was supplied through a hollow shaft to one blade of a two-blade standard disc-turbine impeller. The size of ventilated cavities produced at various impeller spe... [more]
In this study, air was supplied through a hollow shaft to one blade of a two-blade standard disc-turbine impeller. The size of ventilated cavities produced at various impeller speed/gas flowrate combinations was measured. A specially designed bearing mounted on the impeller shaft allowed accurate measurements of the gas pressure inside the cavities to be made. For constant gas flowrates, the impeller speed was increased from zero. At very low impeller speeds, no cavities were formed. At higher speeds cavities formed which grew in length as the speed increased. The cavities grew to a maximum size, which increased with gas flowrate. Once the maximum size was reached, further increases in the impeller speed caused the tails of the cavities to be eroded, resulting in shorter cavities. Cavity pressure was almost constant during the cavity growth region, dropping only slightly. At higher impeller speeds substantial reductions in cavity pressure were observed which mirrored the reduction in cavity size. The critical speed for the transition between cavity growth and dispersion regions was found to increase with increasing gas flowrate. Models are presented that relate the growth region (Zone 1) and dispersion region (Zone 2) of cavity size with the cavity internal pressure for various impeller operating conditions. The implications of these results to the power consumption and gas dispersion quality in impeller stirred gas-liquid reactors are discussed. (Authors)
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1992 |
EVANS GM, JAMESON GJ, ATKINSON BW, 'PREDICTION OF THE BUBBLE-SIZE GENERATED BY A PLUNGING LIQUID JET BUBBLE COLUMN', CHEMICAL ENGINEERING SCIENCE, 47 3265-3272 (1992)
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1992 |
LANGBERG DE, JAMESON GJ, 'THE COEXISTENCE OF THE FROTH AND LIQUID-PHASES IN A FLOTATION COLUMN', CHEMICAL ENGINEERING SCIENCE, 47 4345-4355 (1992)
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1992 |
Jameson GJ, 'Flotation cell development', Conference Series - Australasian Institute of Mining & Metallurgy, 25-31 (1992)
The flotation cell has undergone a number of changes since the process was first introduced in Broken Hill in the early years of this century. The development of the mechanical fl... [more]
The flotation cell has undergone a number of changes since the process was first introduced in Broken Hill in the early years of this century. The development of the mechanical flotation cell is reviewed, followed by a discussion of more recent developments such as the flotation column, the air-sparged hydrocyclone, the Wemco-Leeds cell, the Bahr and Deister columns and the Jameson cell.
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1991 |
PARTHASARATHY R, JAMESON GJ, AHMED N, 'BUBBLE BREAKUP IN STIRRED VESSELS - PREDICTING THE SAUTER MEAN DIAMETER', CHEMICAL ENGINEERING RESEARCH & DESIGN, 69 295-301 (1991)
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1991 |
Clayton R, Jameson GJ, Manlapig EV, 'The development and application of the Jameson cell', Minerals Engineering, 4 925-933 (1991)
The Jameson flotation cell was developed jointly by Mount Isa Mines Limited and Professor G.J. Jameson of the University of Newcastle. The cell has been used in a number of cleani... [more]
The Jameson flotation cell was developed jointly by Mount Isa Mines Limited and Professor G.J. Jameson of the University of Newcastle. The cell has been used in a number of cleaning applications within Mount Isa Mines Limited, and other mines within Australia. In 1990 the cell was tested in a number of flotation plants treating a variety of ores around the world. This paper describes testwork at two medium sized concentrators in Arizona and at the Kidd Creek Concentrator. In these cases Jameson Cell testwork involved treatment of zinc and copper in roughing and cleaning stages. © 1991.
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1991 |
Jameson GJ, Manlapig EV, 'Flotation cell design - experiences with the Jameson cell', AusIMM Extractive Metallurgy Conference, 1-6 (1991)
Results are given for a series of tests in which a 300 mm pilot-scale Jameson cell has been used in copper recleaner flotation, and for the flotation of a lead rougher feed. The r... [more]
Results are given for a series of tests in which a 300 mm pilot-scale Jameson cell has been used in copper recleaner flotation, and for the flotation of a lead rougher feed. The results indicate that the production rate of solids, at the same superficial air velocity Jg, is higher than in conventional columns. Thus in the copper recleaner application, the pulling rate reached 14 gm/cm2/min compared with between two and three for an operating column, while in the lead cleaner application the comparable figures were 12 - 14 gm/cm2/min for the Jameson cell vs 8 - 9 gm/cm2/min for a test column. A froth crowder was used to increase the air superficial velocity Jg in the Jameson cell in the copper recleaner, while holding the collection mechanism and pulp feed rates constant. The recovery increased from 50 per cent to over 90 per cent, suggesting that recovery is controlled mainly by the froth conditions, rather than the particle-bubble interactions in the downcomer.
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1990 |
Parthasarathy R, Ahmed N, Jameson GJ, 'Dispersion characteristics of fine bubbles in an agitated vessel (1990)
Dispersion characteristics of gas phase in a gas-liquid stirred vessel were studied with bubbles of two different sizes, in terms of the stirrer speeds required to disperse them c... [more]
Dispersion characteristics of gas phase in a gas-liquid stirred vessel were studied with bubbles of two different sizes, in terms of the stirrer speeds required to disperse them completely in the vessel. As expected, observations show that smaller bubbles are dispersed and recirculated at lower speeds, thus giving larger holdups for the same operating conditions. It has been found that aerated power number versus aeration number plots can be used to identify the stirrer speeds required for the 'complete dispersion' (N "SUB CD" ) and 'recirculation' (N "SUB R" ) of bubbles. Simple expressions, based on the bubble terminal rise velocity and average liquid velocity in the tank, are suggested to predict N "SUB CD" and N "SUB R" . There is reasonable agreement between the predicted and the experimentally determined values. (A)
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1990 |
Parthasarathy R, Ahmed N, Jameson GJ, 'Dispersion characteristics of fine bubbles in an agitated vessel', CHEMECA '90, Australasian Chemical Engineering Conference, 1180-1187 (1990)
Dispersion characteristics of gas phase in a gas-liquid stirred vessel were studied with bubbles of two different sizes, in terms of the stirrer speeds required to disperse them c... [more]
Dispersion characteristics of gas phase in a gas-liquid stirred vessel were studied with bubbles of two different sizes, in terms of the stirrer speeds required to disperse them completely in the vessel. As expected, observations show that smaller bubbles are dispersed and recirculated at lower speeds, thus giving larger holdups for the same operating conditions. It has been found that aerated power number versus aeration number plots can be used to identify the stirrer speeds required for the 'complete dispersion' (NCD) and 'recirculation' (NR) of bubbles. Simple expressions, based on the bubble terminal rise velocity and average liquid velocity in the tank, are suggested to predict NCD and NR. There is reasonable agreement between the predicted and the experimentally determined values.
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1989 |
Ahmed N, Jameson GJ, 'Flotation Kinetics', Mineral Processing and Extractive Metallurgy Review, 5 77-99 (1989)
The physical variables that influence the rate of flotation are examined. The probabilistic model of flotation is used to establish the effect of the particle si2e and density, bu... [more]
The physical variables that influence the rate of flotation are examined. The probabilistic model of flotation is used to establish the effect of the particle si2e and density, bubble size and agitation on the rate of flotation. In quiescent flotation, it appears that the flotation rate is limited by the particle-bubble collision and subsequent attachment of the particle to the bubble. For fine (<20 ftm) or low density particles the remedy for low recovery rates would be to either use small bubbles of the order of 100 ftm, or to use moderate to high agitation with larger bubbles. In the usual turbulent conditions, the limit is set by the destruction of the bubble-particle aggregates. Broadly speaking, the same parameters favour both attachment and detachment so that the ultimate flotation rate is a compromise between these two competing mechanisms. The bounds which define the best agitation level and bubble size to use are strong functions of the particle size and density. This results in conflicting requirements for the optimum flotation of the fine and the coarse particles. Best conditions for the flotation of each are indicated. © 1989, Taylor & Francis Group, LLC. All rights reserved.
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1988 |
Jameson GJ, 'NEW CONCEPT IN FLOTATION COLUMN DESIGN.', Minerals and Metallurgical Processing, 5 44-47 (1988)
A column flotation cell is described in which the contact between the feed and the air stream is made in a mixing device at the top of a vertical downcomer. The air-liquid mixture... [more]
A column flotation cell is described in which the contact between the feed and the air stream is made in a mixing device at the top of a vertical downcomer. The air-liquid mixture flows downward to discharge into a shallow pool of pulp in the bottom of a short cylindrical column. The bubbles disengage and rise to the top of the column to overflow into a concentrate launder while the tails are discharged from the bottom of the vessel. The main advantages of the device are that the overall height of the column is reduced to about 1 m (3 ft) and the column can be self-inducing with respect to the air supply. Experimental results are given from tests on a feed stream to a conventional zinc cleaner circuit. Using wash water to reduce gangue entrainment, the column gave high concentrate grades and high recoveries.
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1986 |
Dave NC, Jameson GJ, 'RE-ENTRAINMENT AND PRESSURE-DROP IN KNITTED-WIRE-MESH MIST ELIMINATORS. 236-241 (1986)
Liquid hold-up in wire-mesh mist eliminators has been measured. Ergun-type equation is proposed to predict the pressure drop across the mist eliminator over the entire range of op... [more]
Liquid hold-up in wire-mesh mist eliminators has been measured. Ergun-type equation is proposed to predict the pressure drop across the mist eliminator over the entire range of operation. Pressure drop, measured at five different conditions of liquid loadings for two different types of mist eliminators, compare reasonably well with the values predicted by the model.
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1985 |
AHMED N, JAMESON GJ, 'THE EFFECT OF BUBBLE-SIZE ON THE RATE OF FLOTATION OF FINE PARTICLES', INTERNATIONAL JOURNAL OF MINERAL PROCESSING, 14 195-215 (1985)
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1984 |
Jameson GJ, 'PHYSICAL ASPECTS OF FINE PARTICLE FLOTATION.', Symposia Series - Australasian Institute of Mining and Metallurgy, 215-232 (1984)
In the flotation of fine particles, problems arise which do not occur with coarse-ground pulps. For example, the presence of colloidal or near-colloidal gangue particles gives ris... [more]
In the flotation of fine particles, problems arise which do not occur with coarse-ground pulps. For example, the presence of colloidal or near-colloidal gangue particles gives rise to excessive entrainment in the froth, with reduced grade as a consequence. If the values themselves are finely disseminated, the recovery usually decreases as the particles diminish in size, so a low recovery is combined with poor grade. This paper is concerned mainly with recent investigations which appear either to highlight or identify the causes of various problems with fines, or which may point the way to the future. For present purposes, we shall consider that the surfaces of the particles to be floated are suitably prepared, so that they are hydrophobic and will form a finite static contact angle with an air-liquid interface. The discussion deals mainly with the experimental evidence for the effect of the numerous variables on the flotation rate, or recovery, of fines, and the measures which can be taken to improve recovery. The behaviour of fines in the froth is also considered. Refs.
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1984 |
Jameson GJ, 'Physical aspects of fine particle flotation.', Principles of Mineral Flotation: the Wark Symposium, 215-232 (1984)
'Fine' particles are generally considered to be < approx 20 mu m in diameter. The special problems arising with fines can probably be ascribed to low inertia and elec... [more]
'Fine' particles are generally considered to be < approx 20 mu m in diameter. The special problems arising with fines can probably be ascribed to low inertia and electrical forces. The overall flotation rate is the result of a balance between collection or attachment mechanisms and those of detachment. The effect of bubble size and the charge on particles and bubbles are discussed. Other topics covered include slime coatings, colloid flotation, bulk phenomena in the froth, and particles in froth films.-J.M.H.
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1984 |
Jameson GJ, 'Physics and hydrodynamics of bubbles.', IN: THE SCIENTIFIC BASIS OF FLOTATION, PROC. NATO ADVANCED STUDY INST., (CAMBRIDGE, U.K.: JUL. 5-16, 1982), K.J. IVES (ED.),, 53-77 (1984)
A detailed consideration of the physics and hydrodynamics of bubbles is presented. Results of experiments for air bubbles of a variety of shapes in water, for which the reasons ar... [more]
A detailed consideration of the physics and hydrodynamics of bubbles is presented. Results of experiments for air bubbles of a variety of shapes in water, for which the reasons are discussed, are presented. The theory of spherical, ellipsoidal and spherical lapped bubbles are briefly touched on in the discussion. Bubble behaviour in viscous liquids, the effect of adsorbed surfactants and the use of flotation cells are dealt with. (P.J.B.)
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1982 |
Jameson GJ, 'Experimental techniques in flotation.', IN: THE SCIENTIFIC BASIS OF FLOTATION, PROC. NATO ADVANCED STUDY INST., (CAMBRIDGE, U.K.: JUL. 5-16, 1982), K.J. IVES (ED.),, 193-228 (1982)
A review of available techniques to investigate basic mechanisms involved in flotation processes is presented. Bubble-particle attachment, problems involved with fine and coarse p... [more]
A review of available techniques to investigate basic mechanisms involved in flotation processes is presented. Bubble-particle attachment, problems involved with fine and coarse particles, the effect of electrically charged bubbles which occurs with colloidal particles froth studies and test cells are considered particularly. The results of experiments are discussed in equal detail to the techniques. (P.J.B.)
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1980 |
Del Cerro C, Jameson GJ, 'The behavior of pentane, hexane, and heptane on water', Journal of Colloid And Interface Science, 78 362-375 (1980)
It has been found that then-alkanes pentane, hexane, and heptane do not spread when placed on water. Provided the vapor phase is saturated with the appropriate hydrocarbon, heptan... [more]
It has been found that then-alkanes pentane, hexane, and heptane do not spread when placed on water. Provided the vapor phase is saturated with the appropriate hydrocarbon, heptane and hexane form circular floating lenses. The behavior of pentane is more complex. It appears that liquid pentane islands are formed, floating in equilibrium with relatively thick uniform layers. Models for predicting the van der Waals interaction energy for n-alkane/water systems by macroscopic Lifshitz theory are examined in the light of the experimental results. The model which appears best to fit the observations is that which includes all the available spectroscopic data, and it therefore appears essential to include contributions over the whole spectral range. Using this model, Hamaker constants AWOA are calculated in the limit as the thickness l ¿ 0; these are positive for all the n-alkanes 5 < n = 16, suggesting that lenses should form for all thicknesses. However, the chemical potential of the film changes sign with increasing l, and passes through a minimum. The curves are interpreted to indicate that lenses should form in equilibrium with layers of molecular proportions; intermediate thicknesses are precluded. © 1980 Academic Press, Inc. All rights reserved.
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1980 |
Jameson GJ, 'Recent progress in multi-phase flow.', IN: SUPPLEMENT TO PROC. 7TH AUSTRALASIAN CONF. ON HYDRAULICS & FLUID MECHANICS, PREPRINTS OF PAPERS, (BRISBANE, AUSTRALIA: AU, (1980)
Work which has been carried out in Australia over the past decade in the field of multiphase flow is reviewed. The topics covered include fluidization, entrained flows, hydraulic ... [more]
Work which has been carried out in Australia over the past decade in the field of multiphase flow is reviewed. The topics covered include fluidization, entrained flows, hydraulic transport, vertical pneumatic transport, gas-liquid flows and interactions between suspended particles. (A)
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1979 |
Angelidou C, Psimopoulos M, Jameson GJ, 'Size distribution functions of dispersions', Chemical Engineering Science, 34 671-676 (1979)
The size distribution function of bubbles in thermodynamic equilibrium with the surrounding liquid has been derived in the absence of gravity. The derivation has been based on the... [more]
The size distribution function of bubbles in thermodynamic equilibrium with the surrounding liquid has been derived in the absence of gravity. The derivation has been based on the assumption that the gas is dispersed into bubbles in a completely random way in respect of the energies of the bubbles. The size distribution function of bubbles obtained when surface tension effects are neglected is of the same form as the empirical Nukiyama-Tanasawa distribution, and gives also the size distribution function of droplets consisting of an incompressible liquid when the way the liquid is dispersed into droplets is assumed to be completely random with respect to the volumes of the droplets. The derived size distribution functions agree well with the experimental size distributions of bubbles in water having been generated by an air entrainment process at the surface of the water or behind a ventilated body. © 1979.
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1979 |
Sandhu N, Jameson GJ, 'An experimental study of choked foam flows in a convergent-divergent' nozzle', International Journal of Multiphase Flow, 5 39-58 (1979)
Choked flow of a foam in a convergent-divergent nozzle has been investigated. The foam consisted of air and a solution of a surface active agent in water. The upstream gas-liquid ... [more]
Choked flow of a foam in a convergent-divergent nozzle has been investigated. The foam consisted of air and a solution of a surface active agent in water. The upstream gas-liquid volume ratio d0 was in the range 0.053-1.57. The experimental results are in very good agreement with a homogeneous frictionless nozzle flow theory, assuming isothermal behaviour of the gas and no relative motion between the phases, for throat gas-liquid volume ratios d1 as high as 0.8; for ratios in the range 0.8 < dt < 2.98 the agreement, while only approximate, is still quite close. Departures from the homogeneous theory are explained in terms of (a) the failure of the assumption of the isothermal behaviour and (b) the existence of relative velocity between the phases. The latter effect predominates at low values of d1 but at large values, it appears that both contribute to errors in the predictions. © 1979.
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1978 |
Motarjemi M, Jameson GJ, 'Mass transfer from very small bubbles-the optimum bubble size for aeration', Chemical Engineering Science, 33 1415-1423 (1978)
Measurements have been made of mass transfer coefficients KL of small oxygen bubbles of diameter 100-1000 µm, rising at their terminal velo. The measured coefficients are used tog... [more]
Measurements have been made of mass transfer coefficients KL of small oxygen bubbles of diameter 100-1000 µm, rising at their terminal velo. The measured coefficients are used together with values from the literature, to calculate the proportion of oxygen transferred from a bubble of air or. © 1978.
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1978 |
Burman JE, Jameson GJ, 'Growth of spherical gas bubbles by solute diffusion in non-Newtonian (power law) liquids', International Journal of Heat and Mass Transfer, 21 127-136 (1978)
In this work, diffusive bubble growth in newtonian liquids and non-Newtonian liquids of the power law type is studied. Three regions are considered, the first where growth is limi... [more]
In this work, diffusive bubble growth in newtonian liquids and non-Newtonian liquids of the power law type is studied. Three regions are considered, the first where growth is limited entirely by the rate of arrival dissolved gas at the bubble surface, the second where growth is limited entirely by hydrodynamic forces and the third, a general case, where both diffusion and hydrodynamics play a part. Parameters which have previously been used to define regions where viscosity, inertia, surface tension and diffusion are important are shown to hold good for power law liquids. It is found that, all else being equal, bubbles in power law liquids grow more slowly the smaller the characteristic exponent. © 1978.
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1978 |
Collins GL, Motarjemi M, Jameson GJ, 'A method for measuring the charge on small gas bubbles', Journal of Colloid And Interface Science, 63 69-75 (1978)
A method is described for measuring the charge on small gas bubbles. The bubbles are generated by electrolysis in a microelectrophoresis cell, in such a way as to rise vertically ... [more]
A method is described for measuring the charge on small gas bubbles. The bubbles are generated by electrolysis in a microelectrophoresis cell, in such a way as to rise vertically upward across a "stationary level." The cell cross section measures 1 × 10 mm and these small dimensions allow close temperature control thereby minimizing interference from convection currents. Keeping the bubble to the stationary level automatically compensates for electroosmotic streaming. Zeta potentials were measured in solutions of cetyltrimethylammonium bromide (CTAB) and sodium sulfate which were being used to suspend polystyrene latex particles in flotation experiments. The measured potentials had the same sign and magnitude as those of the latex particles at the same electrolyte concentrations. © 1978.
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1977 |
Collins GL, Jameson GJ, 'Double-layer effects in the flotation of fine particles', Chemical Engineering Science, 32 239-246 (1977)
Experiments have been conducted in which the charges on particles and bubbles in a flotation process have been measured. The particles were polystyrene latices of diameters betwee... [more]
Experiments have been conducted in which the charges on particles and bubbles in a flotation process have been measured. The particles were polystyrene latices of diameters between 4 and 20 µm. The bubbles were of mean diameter 53 µm. A cationic surfactant was used to promote flotation, and the charge on the particles and bubbles was controlled by addition of sodium sulphate solution. To measure the charge on bubbles, they were generated electrolytically in a glass electrophoresis cell so that they rose vertically up a "stationary level" in the cell, while at the same time moving sideways under the action of a horizontal potential gradient. The horizontal velocity, taken with the known potential gradient, gave the electromobility. The bubbles were found to carry the same sign as the particles (positive) and under the same electrolyte concentrations, the change on the particles and bubbles was approximately the same. Experimentally determined rate constants for flotation were found to depend strongly on the bubble and particle charge, decreasing by an order of magnitude as the charge increased from 30 to 60 mv. The data were well correlated by the equation: -1n (kp/dp1.5) = 3.9 + 0.116 UEUB where kp is the rate constant (min-1), dp, is the particle diameter (µm) and UE,UB are the electromobilities (µm/s/V/cm) of the particle and bubble respectively. © 1977.
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1977 |
Angelidou C, Keshavarz E, Richardson MJ, Jameson GJ, 'The Removal of Emulsified Oil Particles from Water by Flotation', Industrial and Engineering Chemistry Process Design and Development, 16 436-441 (1977)
The flotation of emulsified oil particles suspended in low concentrations in water has been studied. Two oils were used: a spontaneously emulsifying cutting oil or machining lubri... [more]
The flotation of emulsified oil particles suspended in low concentrations in water has been studied. Two oils were used: a spontaneously emulsifying cutting oil or machining lubricant, and white spirit, a petroleum based turpentine substitute which was emulsified by intense agitation. The oil concentrations were up to 200 mg/L. To effect the separation, various cationic surfactants were used in the flotation cell which was operated batchwise with an external total recycle. It was found that the rate of flotation in water increased with addition of surfactant up to a limit. The presence of sea salt reduced the flotation rate. Simple mathematical models of the flotation cell are developed for predicting the flotation rate from first principles. The agreement between predicted and measured flotation rates Is quite good. © 1977, American Chemical Society. All rights reserved.
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1977 |
Jameson GJ, Nam S, Moo Young M, 'PHYSICAL FACTORS AFFECTING RECOVERY RATES IN FLOTATION.', Miner Sci Eng, 9 103-118 (1977)
The physical factors that influence the rate of flotation of particles are reviewed. Particular emphasis is placed on the hydrodynamic interactions between particles and bubbles a... [more]
The physical factors that influence the rate of flotation of particles are reviewed. Particular emphasis is placed on the hydrodynamic interactions between particles and bubbles and the dependence of the flotation rate on the particle and bubble sizes. Theory and experiment indicate that the flotation process is first-order with respect to the particle concentration. However, the rate constant is strongly dependent on the particle size and the bubble diameter. For small particles the flotation rate varies approximately as the diameter to the 1. 5 power, so for particles in the range 4 to 30 mu m the rate of removal from a cell is very low. However, it appears that the rate constant should vary inversely as the cube of the bubble diameter so one remedy for low recovery rates would be to use small bubbles of the order of 100 mu m in diameter.
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1976 |
Burman JE, Jameson GJ, 'Diffusional mass transfer to a growing bubble', Chemical Engineering Science, 31 401-403 (1976)
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1976 |
Collins GL, Jameson GJ, 'Experiments on the flotation of fine particles. The influence of particle size and charge', Chemical Engineering Science, 31 985-991 (1976)
The dispersed-air flotation of polystyrene particles of size 4-20 µm has been studied under conditions in which the effect of particle diameter on the rate of flotation could be a... [more]
The dispersed-air flotation of polystyrene particles of size 4-20 µm has been studied under conditions in which the effect of particle diameter on the rate of flotation could be analysed. The particle charge was controlled by electrolyte addition. The particle charge had a drastic effect on the flotation rate, an increase by an order of magnitude being observed when the zeta potential was reduced from 60 to 30 mV. The flotation rate was found to vary as the 1.5 power of the particle diameter, and this exponent was substantially independent of the zeta potential. It is clear that double layer effects on the surfaces of particles and bubbles have significant roles in flotation of particles as small as those studied here. © 1976.
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1976 |
Jameson GJ, Del Cerro MCG, 'Theory for the equilibrium contact angle between a gas, a liquid and a solid', Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 72 883-895 (1976)
An alternative derivation is presented of the equation for the equilibrium contact angle between a gas, a liquid and a plane solid surface. The excess free energy of the system ar... [more]
An alternative derivation is presented of the equation for the equilibrium contact angle between a gas, a liquid and a plane solid surface. The excess free energy of the system around the contact line is minimized with respect to the contact angle ¿0 at constant surface area. Thus the surface tension (or surface free energy) does not appear explicitly in the derivation, although it can be calculated from the theory. The general theory is applied to a system in which the forces of attraction between atoms are of the unretarded London-van der Waals type. The equilibrium contact angle is found as a solution of A13/A11 = 1/2 + 3/4 cos ¿0 - 1/4 cos3 ¿0 where A13 and A11 are the Hamaker constants of the gas-liquid and liquid-liquid interactions respectively. It is argued that Young's equation ¿SV = ¿LV cos ¿0 + ¿SL is incorrect in principle, because in deriving it, it is assumed that the excess free energy resides in planes such as the Gibbs dividing surfaces. Near the contact line the non-uniform interfacial zones overlap and the excess free energy at a point in a particular phase will depend on the properties of the two adjoining phases and their geometry. Thus it is essential in this instance to treat the free energy as a property of the bulk phases and not to idealize it as a surface property.
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1976 |
Seaborn DJ, Jameson GJ, 'Some ion exchange properties of exfoliated vermiculite', Hydrometallurgy, 2 141-155 (1976)
Exfoliated vermiculite was used as an ion exchange medium for the removal of transition metal ions from dilute aqueous solutions. Two different grades of a commercial exfoliated v... [more]
Exfoliated vermiculite was used as an ion exchange medium for the removal of transition metal ions from dilute aqueous solutions. Two different grades of a commercial exfoliated vermiculite were employed. Ion exchange was effected by continuous flow through a packed column. A simple favourable-equilibrium model for the breakthrough curve was found to fit the data provided the flow rate was less than 1.5 ml/cm2 min. Diffusion coefficients for the ions in the vermiculite were estimated from the model to be of the order of 10-9 cm2 sec-1. The times taken to breakthrough were in the order Ni2+ > Cu2+ > Zn2+ > Cr3+. It was found that the breakthrough time of the smaller vermiculite particles was considerably greater than that of the larger particle size. Total cation exchange capacities were determined by batch equilibration. Those of nickel and zinc were of the order of 1 meq/g, whilst those of copper and chromium were of the order of 2 meq/g. These values are of the same magnitude as those found in the literature for similar ions. © 1976.
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1975 |
Lemcoff NO, Jameson GJ, 'Hydrogenation of acetone in a vibrating slurry reactor', AIChE Journal, 21 730-735 (1975)
The behavior of a vibrating column of liquid as a slurry reactor and the dependence of the mass transfer resistances on the frequency of oscillation and liquid temperature were st... [more]
The behavior of a vibrating column of liquid as a slurry reactor and the dependence of the mass transfer resistances on the frequency of oscillation and liquid temperature were studied. The hydrogenation of liquid acetone over Raney nickel was chosen as the model reaction. The tortuosity factor of the catalyst was determined from measurements with two different particle sizes. Copyright © 1975 American Institute of Chemical Engineers
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1975 |
Lemcoff NO, Jameson GJ, 'Solid-liquid mass transfer in a resonant bubble contactor', Chemical Engineering Science, 30 363-367 (1975)
The resonant bubble contactor is a device in which a column of liquid is made to oscillate in a vertical direction, thereby entraining gas bubbles which are carried to the bottom ... [more]
The resonant bubble contactor is a device in which a column of liquid is made to oscillate in a vertical direction, thereby entraining gas bubbles which are carried to the bottom of the column by Bjerknes forces. Large volumes of gas can be entrained, and the fluid becomes highly agitated. In this work, mass transfer to small solid particles in the contactor has been investigated. A study of the effect of frequency of oscillation and diameter of particle on solid-liquid mass transfer rates has been made. The results show a considerable increase in mass transfer coefficient over those normally observed in stirred tanks. Correlations were obtained to represent the data when bubble cycling does and does not occur in the system. © 1975.
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1971 |
Saddy M, Jameson GJ, 'Experiments on the dynamics of phase growth', Chemical Engineering Science, 26 675-684 (1971)
The growth of vapour bubbles at a prepared nucleation site in uniformly superheated liquids has been observed. With acetic acid, the bubble growth follows the asymptotic theory: {... [more]
The growth of vapour bubbles at a prepared nucleation site in uniformly superheated liquids has been observed. With acetic acid, the bubble growth follows the asymptotic theory: {A figure is presented} However for water and solutions of glycerol in water, the exponent was in the range 0·75 to 1·0. It is suggested that the discrepancy is due to the translatory motion of the bubbles as they grow. © 1971.
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1971 |
Saddy M, Jameson GJ, 'Prediction of departure diameter and bubble frequency in nucleate boiling in uniformly superheated liquids', International Journal of Heat and Mass Transfer, 14 1771-1785 (1971)
A theory is presented to describe the motion of vapour bubbles growing at a nucleation site in a uniformly superheated liquid. By incorporating the classical theory for spherical ... [more]
A theory is presented to describe the motion of vapour bubbles growing at a nucleation site in a uniformly superheated liquid. By incorporating the classical theory for spherical phase growth, the equations of translatory motion were solved, enabling the radius and position of the bubble to be calculated as a function of time. The theoretical results are compared with experiments using boiling water and acetic acid. For water the bubble radius was found to vary as (time) 3 4 rather than (time) 1 2 as in the theory, whereas the data for acetic acid were in close agreement with the theory. The predicted values of the departure time of the bubbles were in good agreement with the data, especially at the larger superheats. © 1971.
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1970 |
Rutland DF, Jameson GJ, 'Theoretical prediction of the sizes of drops formed in the breakup of capillary jets', Chemical Engineering Science, 25 1689-1698 (1970)
The breaking up of a liquid jet subject to small disturbances was studied experimentally and theoretically. A non-linear theory was used to calculate the profile of the waves on t... [more]
The breaking up of a liquid jet subject to small disturbances was studied experimentally and theoretically. A non-linear theory was used to calculate the profile of the waves on the surface of the jet at breakup, and also to predict the volume of the main and satellite drops. It was found that the theoretical and experimental drop volumes were in good agreement. However, satellites were observed in all experiments whereas the theory predicts that satellites should not form for dimensionless wavenumbers greater than 0·7. In the experiments it was not possible to make the jets break up into single main drops of uniform size. The results suggest that it may be possible to produce uniformly sized drops if the main and satellite drops have the same volume. © 1970.
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1970 |
Rutland DF, Jameson GJ, 'Droplet production by the disintegration of rotating liquid jets', Chemical Engineering Science, 25 1301-1317 (1970)
The linearized equations of motion for an axially rotating jet of liquid, subjected to an axi-symmetric sinusoidal perturbation, have been solved to give the growth rate of the di... [more]
The linearized equations of motion for an axially rotating jet of liquid, subjected to an axi-symmetric sinusoidal perturbation, have been solved to give the growth rate of the disturbance as a function of the dimensionless wavenumber with the kinematic viscosity, surface tension and rotational frequency appearing in two dimensionless parameters. The results show that the effect of rotation on the instability is to increase the range of unstable wavelengths, to increase the growth rate and to move the point of maximum instability to a shorter wavelength than would occur in a stationary jet of the same viscosity. The theory is tested by measuring the growth rates of controlled disturbances on the surface of axially rotating jets of viscous liquid. It is found that the predicted growth rates are in reasonable agreement except at large wavenumbers. The sizes of the main and satellite drops formed by jet breakup were also measured. The rotation, by increasing the growth rates, markedly reduces the length to breakup. However the centrifugal pressure gradient causes an increase in the rate of growth of the wave crests, resulting in smaller main drops and larger satellite drops than with the non-rotating jet. The sizes of the main and satellite drops have been correlated by simple expressions, being dependent simply on the dimensionless wavenumber. © 1970.
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1970 |
Jameson GJ, Burchell SRC, Gottifredi JC, 'Mass transfer with chemical reaction in a finite falling film', International Journal of Heat and Mass Transfer, 13 1629-1632 (1970)
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1969 |
Cetinbudaklar AG, Jameson GJ, 'The mechanism of flooding in vertical countercurrent two-phase flow', Chemical Engineering Science, 24 1669-1680 (1969)
When a liquid flows down the inside walls of a vertical pipe in which a gas is flowing upward, a critical gas velocity is reached where waves are formed which can grow so large as... [more]
When a liquid flows down the inside walls of a vertical pipe in which a gas is flowing upward, a critical gas velocity is reached where waves are formed which can grow so large as to bridge the tube and cause a change in the flow patterns. This phenomenon is known as "flooding". It is suggested that flooding is caused by the appearance of infinitesimal waves moving with the interfacial velocity of the liquid. The stability of the gas-liquid interface has been examined using a linearized small-perturbation technique, and the critical gas velocity required to cause unstable waves has been calculated. These critical velocities are in excellent agreement with experimental data for the flooding velocity over a wide range of liquid viscosities. Although most of the available experimental data is for air and water (or glycerol-water solutions) the predicted flooding velocities are given in graphical form to enable the flooding point to be calculated for other gases and liquids. © 1969.
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1968 |
Gottifredi JC, Jameson GJ, 'The interpretation of measurements of the amplitude of capillary waves generated by a wind', Chemical Engineering Science, 23 403-405 (1968)
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1968 |
Motamedi M, Jameson GJ, 'A new method for the measurement of the incipient fluidizing velocity', Chemical Engineering Science, 23 791-793 (1968)
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1968 |
Gottifredi JC, Jameson GJ, 'The suppression of wind-generated waves by a surface film', Journal of Fluid Mechanics, 32 609-618 (1968)
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1967 |
Jameson GJ, Kupferberg A, 'Pressure behind a bubble accelerating from rest: Simple theory and applications', Chemical Engineering Science, 22 1053-1055 (1967)
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1966 |
Jameson GJ, 'The motion of a bubble in a vertically oscillating viscous liquid', Chemical Engineering Science, 21 35-48 (1966)
When a small gas bubble is placed in a vertically vibrating viscous liquid, it is subject to a downward force which opposes the buoyancy force due to gravity. In this paper, the m... [more]
When a small gas bubble is placed in a vertically vibrating viscous liquid, it is subject to a downward force which opposes the buoyancy force due to gravity. In this paper, the motion of such a bubble is considered for the special case where the nett force on the bubble is zero, and the bubble undergoes no nett displacement in the liquid. The linearized Navier-Stokes equations are solved to find the viscous drag on the bubble as it moves through the liquid. The theoretical predictions are compared with experimental results and are shown to agree quite well at low Reynolds numbers. © 1966.
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1966 |
Jameson GJ, Davidson JF, 'The motion of a bubble in a vertically oscillating liquid: theory for an inviscid liquid, and experimental results', Chemical Engineering Science, 21 29-34 (1966)
A theory is given to describe the motion of a small spherical bubble in an inviscid liquid which is in forced oscillation with an up and down movement. The theory gives the freque... [more]
A theory is given to describe the motion of a small spherical bubble in an inviscid liquid which is in forced oscillation with an up and down movement. The theory gives the frequency at which the downward force due to oscillation balances the buoyancy force; in this condition there is no net movement of the bubble, and the theory predicts that it should oscillate about a fixed point with an amplitude three times the amplitude imposed on the liquid. These results are only roughly in agreement with experimental data; it is clear that with all conceivable experiments in which a bubble is held stationary by vibration, the effect of viscous forces is important. © 1966.
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1964 |
Jameson GJ, 'Mass (or heat) transfer from an oscillating cylinder', Chemical Engineering Science, 19 793-800 (1964)
An equation has been derived for predicting the rate of mass (or heat) transfer from a cylinder oscillating with simple harmonic motion in an infinite body of fluid. It is shown t... [more]
An equation has been derived for predicting the rate of mass (or heat) transfer from a cylinder oscillating with simple harmonic motion in an infinite body of fluid. It is shown that in certain circumstances the mechanism of the transfer is similar to that of heat transfer from a hot body in a fluctuating stream, in that the bulk of the transfer takes place in a steady streaming flow. The equation has been compared with experimental results obtained in the system benzoic acid/glycerol-water solution, and shown to be in reasonable agreement. The mass transfer coefficients obtained with vibration were up to 28 times higher than those due to free convection alone. © 1964.
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1962 |
Buchanan RH, Jameson G, Oedjoe D, 'Cyclic migration of bubbles in vertically vibrating liquid columns', Industrial and Engineering Chemistry Fundamentals, 1 82-86 (1962)
A new procedure has been developed for bringing gas, liquid, or solid phases into contact to promote exchange phenomena. When liquid columns are subjected to high-amplitude low-fr... [more]
A new procedure has been developed for bringing gas, liquid, or solid phases into contact to promote exchange phenomena. When liquid columns are subjected to high-amplitude low-frequency vertical vibrations, bubbles migrate cyclically from the surface to the bottom, where they aggregate and then move back up the column. The result is violent and rapid mixing of the gas with the liquid and with suspended solids. An equation is derived which permits accurate prediction of the minimum frequency for cyclic migration for the air-water system at atmospheric pressure. Some deviation occurs with liquids whose properties differ markedly from water and at pressures other than atmospheric. © 1962, American Chemical Society. All rights reserved.
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