Professor Michael Bradley BSc Hons, PhD

• Leadership of The Wolfson Centre team in research, consultancy and education
• Member of executive committee of School of Engineering

2013: Bulk Solids Handling Award of the Institution of Mechanical Engineers, for personal contribution to the field of bulk materials handling

2012: Principal investigator of international team receiving the Institution of Mechanical Engineers Bulk Materials Handling Award for Innovation, for development of the Brookfield powder flowability tester

2011: USA R&D Magazine, R&D Top 100, for the powder flowability tester

2010: Shortlisting for Times Higher Education award Research Project of the Year, also shortlisting for IChemE Innovation Award for the powder flowability tester

2006: Member of the team receiving "Highly Commended" in IChemE Chemistry Innovation Award – 'Innovation in Applied Catalysis and Colloid Science for the Quality in Particulate Manufacturing' project

• Chairman of Technical Committee of Solids Handling and Processing Association (SHAPA)
• Member of Council of Solids Handling and Processing Association (SHAPA)
• Member of editorial board of IMechE Journal of Process Mechanical Engineering
• Member of international scientific council of the tri-ennial international conference on conveying and handling of particulate solids
• Member of the European Federation of Chemical Engineers' workshop on the mechanics of particulate solids
• Previously member of British Standards Institution technical panels MHE/9 Materials Handling and MHE/9/1 Pneumatic Conveying
• Founder member of ISO standardisation committee TC 238 / WG4 / TG1, Safety Standards for Pelletised Biofuels

Professor Bradley's interests lie in the behaviour of powders and particulate materials. Researching the science behind how they behave, developing characterisation techniques to measure how they behave, models to predict their behaviour in manufacturing and handling processes, and the use of these techniques in advanced professional practice for design of improved solids handling and processing systems in all industries that use powders and bulk materials.

Powders and bulk solids are critical to our lives, used in every manufacturing industry, from pharmaceuticals to coal mining and food to construction; yet their behaviour is still only loosely understood and there is vast work to do to improve the poor performance of industrial solids handling systems which lead to losses of billions world-wide in productivity.

Professor Bradley's research, funded by many different bodies and also industry, has contributed many new techniques that have been applied to hundreds of industrial solids processing systems by not only blue chip companies from Glaxo SmithKline to Unilever and BP to United Biscuits, but also many SMEs processing metals, solid fuels, foods, plastics, waste etc.

In addition to research, Professor Bradley leads a very strong outreach effort from The Wolfson Centre, including training around 200 engineers from industry every year in solids handling technology, undertaking around 50 consulting projects of values from £500 to £100,000 each annually, and supporting around 30 conferences and seminars annually. This is having a real effect on practice in the industry, with now well over 500 companies internationally having embedded his research results to improve their operations.

Key funded projects

The following three examples cover only a narrow part of the broad range of research conducted by Professor Bradley into powder behaviour and utilisation, and engineering of powder processing systems. However, they serve to illustrate the significant depth of impact that his research has had, on a wide range of manufacturing and other industries that utilise powders.

A particularly influential research project was the 'Development of an economic yet useful powder flowability measuring device' This was a collaborative with six industry partners from Europe and the US which sought to deliver a novel instrument for measurement of powder flow properties, for purposes of powder formulation development and quality assurance. Although powders are an input to almost every manufactured material and item and the flow properties of these powders affects their performance profoundly, previously the only instruments available for measuring the flow properties were either very expensive and requiring an expert to use them, or crude and without scientific link to the real powder behaviour in the plant. The project successfully delivered a completely new design of instrument that is now sold around the world, and used by many blue-chip companies as an inherent part of their development and QA processes, from food, pharmaceutical and cosmetics to chemicals and minerals.

The project was strongly grounded in the practical powder processing problems, product development and QA requirements within the industrial collaborators which were established by a thorough survey and analysis of their plant operations. These were set against the existing knowledge of powder mechanics and established measurement techniques, and a new instrument conceived. Much detailed research was undertaken to determine the optimum test cell geometry, testing protocol and data analysis methods. Testing was also carried out to ensure that the machine has very low dependency on user skill or technique, very good repeatability, that it can deal with all the many different patterns of powder behaviour that are seen in practice, and has a direct impact on the plant problems identified. Much additional research was required to come up with the right mechanical, instrumentation and control arrangements to give the required high accuracy in a design suitable for high volume, low cost production.

In just three years since launch, this has become the most widely used tester in the world for measuring the shear properties of powders. The project and the instrument have received many accolades, including the prestigious R&D 100 award of the US R&D magazine (www.rdmag.com/award-winners/2011/08/powder-flow-measurement-gets-twist), the 2012 Institution of Mechanical Engineers Innovation in Bulk Solids Handling award, and short listing for a Times Higher Education award and an IChemE Innovation award (2010).

This project has continued to spawn further research projects, for example, DEFRA Advanced Food Manufacturing LINK project 'Control of Powder Flow Properties' which is developing a toolkit consisting of the powder flow tester, a software model and an operational protocol to allow manufacturers of engineered food powders to quickly optimise powder formulations to meet the necessary flow property window for efficient dispersion and processing. Further research is expected to follow, due to the ongoing challenges that food and other powder manufacturers face in obtaining optimum process yield, consistency of quality and minimum cross-contamination. All of these are critically controlled by powder flow behaviour (including powder-surface interaction) which can now be studied much more quickly, efficiently and accurately thanks to the powder flowability tester. A substantial and increasing flow of industrial consultancy in this topic has been established, currently around 30 projects per annum in The Wolfson Centre involving the use of the PFT in various aspects of powder development and process optimisation across diverse fields from minerals and powder metals to pharmaceuticals and petro-chemicals, as well as food.

Another particularly influential project was 'Handling Characteristics of Biomass/ Coal Mixes for Co firing: Measurement techniques and establishing benchmarks' which received a British Coal Utilisation research association grant and was supported by E-On, intended to identify key fuel handling issues at the time the UK power generation industry was just beginning to burn renewable solid fuels (biomass) for carbon reduction. With many different candidate biomass materials under consideration, and early experience of expensive process stoppages and safety issues, this project was funded by the industry to uncover the fundamental relationships between the raw materials the processing, the effects of handling and the resulting handling and safety.

In addition to some important peer review papers, the new knowledge yielded by the project also resulted in a document Best Practice Guide for Handling of Coal and Coal/Biomass Mixes for Power Generation, endorsed by industry bodies the Solids Handling and Processing Association and the Materials Handling Engineers' Association, and also a comprehensive post-experience short course. These embody a concise set of principles for power generators, biomass importers and logistics companies, plant constructors and maintenance personnel, covering such issues as reliable flow, dust hazards and how to contain them, occupational safety, material spoilage, self heating and fire, equipment selection and design, and a wide range of other technical issues relating to safe, efficient and economical operation of the biomass logistics chain from field to furnace. The Best Practice Guide is in use in over 300 companies in 34 countries around the world, and the principles determined have been embodied in many of the large scale biomass conversions of coal-fired power plants, including the Drax Eco-Store, a£90 million project to convert the UK's largest coal fired station to biomass, for which Professor Bradley was a member of the principal design team.

Industry has funded 31 follow-on projects in The Wolfson Centre on biomass. These include further research on extreme shape particles, particle breakage and dust production in handling, and how these behaviours are influenced by the production conditions of the pellets. The centre also carries out consultancy, including for Tilbury, Uskmouth, Eggborough power stations, power generators Alstom, Vattenfall, E-On, RWE etc. and various ports, terminals and construction companies. In many cases the project teams have appointed either Professor Bradley or one of his Wolfson Centre research team as a member or advisor, to ensure their system designs observe the principles identified. In the last three years, more than 250 engineers from 80 companies in 13 countries have paid to attend the Wolfson Centre technical course 'Biomass Handling' arising from the original and spin-out projects, either at the university or as in-company courses in order to obtain the knowledge required to embed the design principles in their plants and projects.

Both research and consultancy in biomass handling and processing logistics are continuing to grow at The Wolfson Centre and this trend is likely to continue as the use of biomass for power generation and bio-fuel production around the world increases.

'Evaluation of Electrostatic Effects in Pharmaceutical Blend Processing' was a pharmaceutical industry-funded project which sought to investigate quantitatively the role of electrostatics versus other driving forces in a number of common powder handling issues, with particular reference to undesired segregation of active ingredients in blends, and coating of these on surfaces. These phenomena, which cost many millions of pounds a year of loss due to disposal of out-of specification blends, are often blamed on electrostatic effects, but little hard evidence was previously available to be confident about the relative effects of electrostatics versus other natural forces commonly controlling powder behaviour. Engineers in industry tended to have a lack of confidence in going forward with process changes, especially given the massive cost of re-validation of the processes following changes.

The project involved the setting up of a unique facility at The Wolfson Centre in which electrostatic charging on powders could be measured and controlled, and the effects on flow and movement measured, all under controlled ambient conditions.

The study included a series of real-world case studies in operating pharmaceutical plants, fundamental investigations in charge measurement and neutralisation in the lab, and significant pilot plant work. This revealed that in most cases of real processing systems in industry, segregation is not driven by electrostatics but by air flow effects. Adhesion of dust to plant surfaces that are not subject to sliding of bulk powder can be aided by electrostatics. This was a fundamental breakthrough, showing how these common problems need to be approached in order to solve them in real plants, and has led on to various follow-on projects funded by industry.

Equally significantly, the project led to suspicion that the powder blends in question are likely to contain bi-polar charge which was not detectable by measuring methods then available apart from one highly expensive and sophisticated method.

Accordingly, further work (a PhD project) was funded from University investment to investigate whether it would be possible to measure bi-polar charges on powders using simple, lower-cost sensors by introducing novel data analysis methods. The result has been a prototype instrument that is small and light-weight, potentially cheap to manufacture, and able to detect when a powder has both positive and negative charges present and quantify them. Apart from two peer review papers describing this technique and its use, the prototype instrument has been tested by a major pharmaceutical manufacturer and found to give very useful insight into the charging behaviour of blends in real processing scenarios. Currently, discussions are being held with an instrument manufacturer that sells electrostatic monitoring equipment, with a view to commercialising the instrument in the next couple of years.

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