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Fernando J. Muzzio – One of the best experts on this subject based on the ideXlab platform.
comparing mixing performance of uniaxial and biaxial bin BlendersPowder Technology, 2009Co-Authors: Amit Mehrotra, Fernando J. MuzzioAbstract:
Abstract The dynamics involved in powder mixing remains a topic of interest for many researchers; however the theory still remains underdeveloped. Most of the mixers are still designed and scaled up on empirical basis. In many industries, including pharmaceutical, the majority of blending is performed using “tumbling mixers”. Tumbling mixers are hollow containers which are partially loaded with materials and rotated for some number of revolutions. Some common examples include horizontal drum mixers, v-Blenders, double cone Blenders and bin Blenders. In all these mixers while homogenization in the direction of rotation is fast, mediated by a convective mixing process, mixing in the horizontal (axial) direction, driven by a dispersive process, is often much slower. In this paper, we experimentally investigate a new tumbling mixer that rotates with respect to two axes: a horizontal axis (tumbling motion), and a central symmetry axis (spinning motion). A detailed study is conducted on mixing performance of powders and the effect of critical fundamental parameters including blender geometry, speed, fill level, presence of baffles, loading pattern, and axis of rotation. In this work Acetaminophen is used as the active pharmaceutical ingredient and the formulation contains commonly used excipients such as Avicel and Lactose. The mixing efficiency is characterized by extracting samples after pre-determined number of revolutions, and analyzing them using Near Infrared Spectroscopy to determine compositional distribution. Results show the importance of process variables including the axis of rotation on homogeneity of powder blends.
effect of high shear blending protocols and blender parameters on the degree of api agglomeration in solid formulationsIndustrial & Engineering Chemistry Research, 2009Co-Authors: Marcos Llusa, Kurt Sturm, Osama S Sudah, Howard J Stamato, David J Goldfarb, Hanu Ramachandruni, Steve Hammond, Mark R Smith, Fernando J. MuzzioAbstract:
This paper examines the effect of three protocols with several units and blender parameters on the mitigation of active pharmaceutical ingredient (API) agglomeration in solid formulations. The three protocols either preblend API with a portion of excipients in a high shear unit followed by dilution in a large blender or prepare the entire blend in a single blender followed by milling. In general, the three protocols yield blends with statistically similar API concentration variance and deagglomeration. The scale-up of the three protocols leads to more extensive API deagglomeration, which suggests that blender parameters still influence the degree of API deagglomeration, even when high shear units are present in the protocol. Lower blender fill levels and larger Blenders lead to blends with fewer API agglomerates. Regarding the use of blender internals, results show that baffles have no substantial effect on API agglomeration. The inclusion of a moving internal (i.e., impeller) in a bin blender may not alw…
Quality by Design Methodology for Development and Scale-up of Batch Mixing ProcessesJournal of Pharmaceutical Innovation, 2008Co-Authors: Patricia M. Portillo, Marianthi Ierapetritou, Silvina Tomassone, Christine Mc Dade, Donald Clancy, Petrus P. C. Avontuur, Fernando J. MuzzioAbstract:
In this study, a quality by design approach was applied to the design and scale-up of a batch mixing process. Mixtures of acetaminophen and lactose were sampled at different mixing times using a groove sampler. Samples were subsequently analyzed using NIR reflection spectroscopy. The effects of four processing parameters on the empirical mixing rate in a bin blender were examined. Blender rotation rate (two levels), powder fill level (two levels), powder cohesion (two levels), and blender size (three levels) represent the four parameters studied. Blender geometry and blender loading method were treated as constant parameters. Statistical analysis was used to assess the impact each parameter had on the mixing rate. Blender size ( p = 0.02), powder cohesion ( p = 0.05), and rotation rate ( p = 0.07) all significantly affected the mixing rate. The least significant parameter was the vessel fill level ( p = 0.18), indicating mixing performance is not strongly affected by fill level, given the range studied.
Best Amazon Blenders – One of the best experts on this subject based on the ideXlab platform.
The Best Blenders: CleanBlend Professional 3-Horsepower Commercial Blender, 1999Co-Authors: Best Amazon BlendersAbstract:
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the best Blenders waring 018794 blender switch, 1999Co-Authors: Best Amazon BlendersAbstract:
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The Best Blenders: Bosch MUM4405UC Compact Mixer With Blender & Shredder, 1999Co-Authors: Best Amazon BlendersAbstract:
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Troy Shinbrot – One of the best experts on this subject based on the ideXlab platform.
V-blender segregation patterns for free-flowing materials: effects of blender capacity and fill level.International Journal of Pharmaceutics, 2004Co-Authors: Albert Alexander, Troy Shinbrot, Barbara Alice Johnson, Fernando J. MuzzioAbstract:
Stable segregation patterns are shown to form in V-Blenders over a wide range of vessel capacities, fill levels, and rotation rates. Slight changes in either rotation rate or fill level induce changes in pattern formation. Trajectory segregation in two regions of the flow, accumulating over many flow periods, drives segregation pattern formation. Scaling criteria derived to relate particle velocities to vessel size and rotation rate in rotating cylinders successfully predict the rotation rate for the transition between patterns across V-Blenders of 0.8-26.5 quart total capacity. This agreement suggests that pattern formation is governed by the magnitude of particle velocities. Regardless of vessel size, when particle velocities at specific regions of the blender are below a certain value, one particular pattern appears, and when they increase beyond that speed (i.e. by changing the rotation rate or the vessel size), a different pattern emerges. A scaling relation between segregation pattern formation and blender fill level was not identified because the complex flow patterns in the V-blender (the length of the flowing layer and the mixture center of mass relative to the blender are constantly oscillating) preclude the determination of a relationship between blender fill level and particle velocities.
Segregation patterns in V-BlendersChemical Engineering Science, 2002Co-Authors: Albert Alexander, Fernando J. Muzzio, Troy ShinbrotAbstract:
Abstract We report several segregation patterns in V-Blenders partially filled with mixtures of glass beads differing in size. Three dominant patterns are found, including one in which larger and smaller particles migrate to opposite halves of the blender. Changes in the rotation rate by as little as 3% can cause a change of pattern. Analysis of particle pathlines suggests that segregation in this vessel may be dominated by ‘trajectory segregation’, i.e. the inability of larger, more inertial, particles to navigate sharp bends in pathlines.
Computational approaches to granular segregation in tumbling BlendersPowder Technology, 2001Co-Authors: Troy Shinbrot, Marco Zeggio, Fernando J. MuzzioAbstract:
We discuss cellular automata (CA) simulations of granular segregation in several different tumbling Blenders, including simple rotating drums, V-blender shells, drums tumbling end-over-end and double-cones. In all cases, simplified CA generates data that agree surprisingly well with companion experiments. This implies that a predictive understanding of segregation mechanisms in a wide variety of problems may be achievable using relatively simple algorithms.