John Bridgwater, 1938–2021

Professor John Bridgwater, who shaped the chemical engineering departments at Cambridge and Birmingham, and who as President of IChemE pushed for chemical engineering to realise its role in sustainable development, has died aged 83.

Professor Bridgwater obtained an MA in chemical engineering from St Catharine’s College Cambridge in 1959, and an MSE in the same subject from Princeton University in 1961. He worked as a chemical engineer at Courtaulds before moving into academia in 1964 at the University of Cambridge, while at the same time studying for his PhD, which he gained in 1973.

He was appointed Esso Research Fellow in Chemical Engineering at Hartford College, Oxford from 1971-1973, subsequently taking on the role as Lecturer in Engineering Science at the University of Oxford and being appointed Lubbock Fellow in Engineering at Balliol College from 1973-1980.

A move to the University of Birmingham followed as he took up a post as Professor in the School of Chemical Engineering, becoming Head of the School three years later in 1983. In 1989 he became Dean of the Faculty of Engineering and would go on to lead the Ceramics Processing Group in the university’s IRC in Materials for High Performance Applications. His time at Birmingham coincided with a significant expansion of the university and changes in structure, including merging the departments of chemical engineering and minerals engineering. Professor Bridgwater also oversaw the changes introduced by the Engineering Council’s Standards and Routes to Registration (Sartor) which brought in BEng and MEng degrees. In parallel, specialist versions of the chemical engineering degree were introduced for biochemical engineering, environmental management, and minerals engineering.

Professor Bridgwater’s key interest was in particle technology and he did much to initiate new lines of work to open up the discipline and to persuade the funding bodies to support it. Early work with David Bagster in the 1970s on flow over blades led to a series of papers on the fundamental processes that determine the relative motion of particles when these are deformed in the bulk. This could not be exploited until the advent of the positron camera, and he was among the first to recognise the potential of positron emission to make measurements of use to chemical engineers, particularly through the emerging technique of positron emission particle tracking (PEPT). He is also remembered for significant work on attrition and particle breakage and for his work with John Benbow on paste extrusion, which led to the development of the widely used Benbow and Bridgwater equations. In 1983 he became Executive Editor of Chemical Engineering Science, a role which he fulfilled for some 13 years before becoming the Chairman of the journal’s Editorial Board.

In 1993, he returned to Cambridge as Shell Professor of Chemical Engineering and Head of Department. He gave a public lecture published by Cambridge University Press, in which he noted many changes in the subject, including industry becoming interested in designing products and conserving both resources and the environment. Professor Bridgwater oversaw significant changes at Cambridge, including strong growth in student numbers, a redesign of the departmental building, the development of the Magnetic Resonance Research Centre, and the transformation of existing laboratories into the CUBE for bioengineering and biotechnology research.

Professor Bridgwater joined IChemE in 1962, transferring to Fellow in 1974 and served on its Council as an elected member from 1987-1990 before returning as Vice President in 1995 for two years before serving as President from 1997-1998.

When he retired he and his wife Diane went to live in Portishead near Bristol in order to be nearer to their family. They were actively involved with their local church and it was only in the final year before his death in May that he lost his sight and good health. In a memorial published by the University of Cambridge, former colleagues noted his passion for the discipline along with his kindness and desire to help academics, students, support staff and the wider community.

In the Presidential Address he gave in 1997, Professor Bridgwater noted that the profession’s key challenge in the 21st century would be for chemical engineers to use their skills to improve quality of life by fostering employment, advancing economic and social development, and protecting the environment. As had been laid out in the London Communique co-signed by 18 chemical engineering societies, he said that “this challenge encompasses the essence of sustainable development. We will work to make the world a better place for future generations.”

The breadth of the profession, he said, is limited only by the vision of those within it.

Acknowledgements: we thank Professor Bridgwater’s former colleagues at Birmingham and Cambridge for their assistance. These include Professors Joe Biddlestone, Jonathan Seville and Malcolm Mackley. Read Cambridge University’s memorial at https://www.ceb.cam.ac.uk/news/in-memory-john-bridgwater