Dr. Leonardo Borras
Alcon Labs (Novartis company) – leonardo.borras@alconlabs.com The Importance of Early Biophysical Characterization of Antibodies in the Lead Selection Process A critical aspect of the antibody lead selection process is assessing and understanding the biophysical properties of antibody lead candidates. An early characterization helps to reduce or eliminate development issues while allowing for ideal lead selection. We have […]
Taming the material; Techniques for modifying the flow properties of powders
Mike Bradley, Rob Berry and Richard Farnish – The Wolfson Centre, University of Greenwich Powder flow properties can now be measured in ways that give a good indication of the likely behaviour of the powder in a given process, or conversely allow us to design a process so that it will work reliably with a given […]
Characterisation of Flowability of Cohesive Powders by Indentation
The characterisation of bulk behaviour of cohesive powders is very important in processing of particulate solids, e.g. for reliable powder flow out of storage vessels. Therefore the bulk mechanical properties of cohesive powders have been analysed extensively at large operational scales and applied stresses, typical of those prevailing in storage vessels. However for filling and […]
Determination of the Macroscopic Cohesion of Fine Powders by the Rain-off Experiment
Abstract The interparticle attraction forces acting between particles or a particle and a device wall play an important role in many powder handling processes such as fluidisation, dry dispersion, transportation etc. In macroscopic modelling of these operations, a popular method of accounting for the effect of internal forces within a bulk powder is to measure the cohesion of […]
Modelling of adhesive frictional material for powder handling applications
Particulates and powders constitute over 75% of material feedstock in industry. Many of these solids exhibit complex cohesive behaviour, leading to handling problems including arching and rat-holing in silo discharge. It is generally recognised that the cohesive strength of a bulk solid is dependent on the prior consolidation stress exerted on the solid. Such cohesive […]
Use of silica nanopowder to improve the fluidization of highly cohesive CO2 adsorbent powders
The flow and fluidisation properties of dry mixtures of highly cohesive Ca(OH)2 fine powder with silica nanopowder were studied with a view to improve the performance of CO2 adsorption by Ca(OH)2 in fluidized bed carbonators. We will show how the light agglomerates of the silica nanopowder act as dispersants for the Ca(OH)2 fine cohesive particles, […]
Micro and Macromechanics of Particle Contacts, Flow and Compression of Ultrafine Cohesive Powders
The rapid production of ultrafine, and therefore cohesive to very cohesive powders (d<10 µm, e.g. very adhering pigment particles) in biotechnology, pharmacuticals, auxiliary materials in catalysis or chromatography, generates a number of serious technical problems and issues due to inadequate apparatus and reliability of processing plants. These problems include particle adhesion or sticking during processing […]
Cohesive Interparticle Forces and Bulk Flow Properties in Fluidisation and Powder Flow
Binary cohesive interparticle forces are often used to describe the aggregative behaviour of particles in gas fluidization applications of fine powders and, sometime, to explain other phenomena in fluidization such as the delayed bubbling in aeratable powders. These forces can be theoretically estimated but hardly measured. The direct measurement of bulk flow properties is a […]
Dense flows of cohesive materials
Flows of granular media still attract attention due to the difficulty to accurately model them. The continuum closure equation allowing predicting such flows are still to be assessed, including in the simplest situations: parallel or steady state dense flows. It has been developed in the recent year a non-Newtonian rheology, so-called µ(I)-rheology, where some viscosity […]