John Davidson, emeritus professor of Chemical Engineering at Cambridge University, U.K., received the Prince Philip Medal from the Royal Academy of Engineering (RAE) at a June 7 awards ceremony in London.
Founded in 1976, the RAE promotes the U.K.'s engineering and technological welfare, and includes some of the country's most eminent engineers. In 1989, Prince Philip, Duke of Edinburgh, a RAE senior fellow, commissioned a gold medal to be "awarded periodically to an engineer of any nationality who has made an exceptional contribution to engineering as a whole through practice, management or education." That's the Prince Philip Medal.
Davidson has contributed significantly to chemical engineering on a global scale, most notably in research in multi-phase flow in fluidization and bubble flow, publishing more than 250 papers in this field. He's still very involved in the industry and is currently working on key projects such as clean coal combustion, which looks to underpin the design of zero-emission coal-fired power plants.
One of his projects focuses on fluidized-bed gasification of sewage sludge. Burn-out studies show how volatiles from a sludge pellet are released and decomposed in a hot fluidized bed of sand. Buoyancy of the pellet is an important factor because it's desirable for volatiles to be released before the pellet rises to the bed's surface. The pellet's rise rate can be surpressed using a slugging bed. Dealing with sewage sludge is a major challenge for U.K. water companies as landfill costs continue to rise.
Another project focuses on the break-up of oil droplets in aqueous liquids. Formation of very fine edible oil droplets in water is important for many industries.This project is taking place in collaboration with Quest International, Naarden, The Netherlands, part of leading flavors and fragrance company Givaudan. Oil droplets are broken up by by passing the suspension through a nozzle with a very high pressure (50–100 bar). Extensive experiments, using the multi-pass-rheometer, show fair agreement between measured droplet size distributions and predictions using computational fluid dynamics to predict the pattern of strain rates.
Davidson and many of his students also worked with and for ICI, which is now defunct (see: "ICI Fades into History," www.ChemicalProcessing.com/articles/2008/082.html). There they focused on fluidized-bed reactor technology and helped develop Pruteen biofermentation reactors. Pruteen is what ICI called microbial protein produced by bacteria grown on methanol produced from methane or natural gas.
The Pruteen project was a pioneering attempt to produce food using microorganisms. The company invested well in excess of £100 million in the initiative, but high production costs and falling prices of competing products led to its demise. Although nutritionally excellent, Pruteen was just too expensive to produce. Like many companies pursuing similar technologies in the 1970s and early 1980s, ICI had no answer to the huge rise in oil prices.
Nevertheless Pruteen technology laid foundations for later work that has produced foods such as Quorn, the low-fat meat-free mycoprotein manufactured by Marlow Foods at Stokesely in Northern England — not far from where ICI conducted the original research.
Additionally, Davidson served on the official committee that investigated the 1974 Flixborough disaster when a cloud of cyclohexane vapor ignited over the Nypro caprolactam plant in the town. With 28 dead and 36 injured, it still ranks as one of the country's worst industrial accidents. (For more on Flixborough and other major chemical industry disasters, see "Bhopal Leaves a Lasting Legacy," www.ChemicalProcessing.com/articles/2009/238.html.)
Davidson also worked briefly with Francis Bacon on developing the Bacon fuel cell, which powered the electrical systems on Apollo 11 and took Neil Armstrong to the moon.
"I am delighted to receive the Prince Philip Medal," Davidson said at the London ceremony. "It gives me the feeling of being a real engineer and not just an academic theoretician."
His accolades include being a foreign associate of the U.S. National Academy of Engineering, Washington, D.C., a foreign fellow of the Indian National Science Academy, New Delhi, India, and foreign member of the Russian Engineering Academy, Moscow, Russia. Davidson also is a past president of the Institution of Chemical Engineers, Rugby, U.K.
"His enthusiasm for his work has inspired many students who have gone on to hold prominent positions in industry and academia," said Lynn Gladden, head of chemical engineering and biotechnology at Cambridge University. "He has made significant contributions to the Pruteen biofermentation reactors — and is seen very much as the father of their subject."
Seán Ottewell is Chemical Processing's Editor at Large. You can e-mail him at firstname.lastname@example.org.