Understanding powder behavior can be daunting but a pragmatic approach can be very effective, says Freeman. It involves making good use of process experience most companies already have.
"The process plant will have been a major investment and often is used to manufacture or process various formulations, whether making bulk material, filling bags or making tablets or capsules. Process engineers will know which materials process efficiently and which are problematic — prone to stoppages and quality issues. Our perspective is that with the FT4 it is now possible to understand why some powders process well and others do not. The benefits of this are that stoppages can be reduced or eliminated and, importantly, new formulations can have properties that suit the plant. This approach works for whole process lines as well as for individual items of plant such as a hopper, feeder or granulator."
BASF, Ludwigshafen, Germany, also is focusing on DEM technology. "BASF Engineering is a partner of the European research program 'PARDEM [particle DEM],' intending to validate the method and parameters for simulation purposes," notes spokeswoman Laura-Rebecca Janz.
Particles and granular solids constitute more than 75% of all raw materials used by industry, according to a European Union (EU) study. Attempts to improve processing via simulations based on classical continuum theory and standard numerical methods and design tools can't always succeed because they can't treat materials as assemblages of discrete objects.
A promising interdisciplinary alternative is DEM, which follows in detail the motion and interaction of particle assemblies. While already established in academia, the method as yet can't handle realistic particle systems of industrial relevance.
The overarching aim of the PARDEM project is to provide high quality training to a group of young researchers to foster multidisciplinary and mutli-industry use of DEM for granular processes. Part of the EU-funded Framework 7 Marie Curie Initial Training Network, it runs from 2009–2013 and currently involves 15 research projects across Europe. The EU has earmarked nearly €5 billion for research within different Marie Curie priority areas.
BASF is heading efforts in the chemical processing sector, with 10 other companies and organizations including Nestle, P&G and NASA leading work in other sectors, ranging from food to equipment manufacturing to space exploration.
The company also is very interested in research for improving reliability of shearing tests commonly used to characterize solids. To this end, it's involved in a series of ongoing round-robin trials being organized by the European Federation of Chemical Engineering that complement efforts to develop its own instruments for measuring and characterizing solids.
Meanwhile, established approaches continue to evolve. Laser diffraction technology in particular may expand its role. Such systems already are widely used in the process industries. For example, Indorama Petrochem recently chose the Mastersizer 2000 particle size analysis system from Malvern Instruments, Malvern, U.K., to provide quality control (QC) for purified terephthalic acid (PTA) production at its site in Rayong, Thailand. A similar system is at the heart of explosivity and powder-handling safety studies by process safety specialist Chilworth Technology, Plainsboro, N.J. Particle size is one of a range of properties examined by Chilworth when determining the flammability of materials and also is a critical parameter in toxicological safety testing of powders.