85 Years of "Rosin-Rammler-Sperling-Bennet Distribution"
85 years ago, a group of scientists developed an essential statistical distribution for particle collectives which was very important for the thermal engineering technology of the twentieth century: the Rosin Rammler Sperling Bennet distribution which is even named after the four researchers involved. The RRSB distribution plays an important role in the field of process technology until now, despite being better known as Weibull Distribution since the 1950s, which goes back to a Swedish scientist.
Especially Prof. Erich Rammler is well known in Freiberg as an important German scientist of the second half of the 20th century for the utilization of lignite. His working place, Leipziger Straße 28, a central building at the Campus, is even named after him. But also the scientist Paul Otto Rosin, who worked at the Bergakademie from 1914 until 1932, has never been forgotten, as a commemorative plaque, which was inaugurated in 2013, at the main entrance is demonstrating.
Graduated as an engineer for metallurgy at the Bergakademie Freiberg in 1914, Paul Otto Rosin, as one of the numerous important alumni and an outstanding German scientist, has a crucial position in the history of the Bergakademie. He has been a researcher of utmost importance in the field of pneumatic drying, coal firing and thermochemical process technology. As coal established as an efficient energy carrier in the 1920s, Rosin worked on the efficient and low-emission utilization of coal as a scarce resource.
Already by 1932, Paul Otto Rosin was internationally well established as a researcher, supported by his ties to the Institute of Fuel in London. After his expulsion of Germany, he worked at the Imperial College and at the Institute of Fuel. His achievements are important for teaching and research until today. He is not only one of the pioneers of the modern coal combustion technology, as founder of the most important statistical particle distribution, but also for the It-diagram of combustion calculation, jointly developed with the chemist Hermann Fehling, which is part of the academic teaching at universities until now.
Rammler and Rosin had a close personal relationship. Erich Rammler had not only been employed in Rosin’s laboratory for fuel technology and industrial thermal engineering technology in Dresden, they also often travelled together. In 1936, caused by the political developments and Rosin being from a jewish family, he sold his private institute to Rammler and emigrated to London in the same year. Fortunately, the emigration to London was a chance for Rosin expand his research to an international level and to start a business career.
Sebastian Nicholas Rosin has continued his father’s lifework as an entrepreneur and creative engineer in the business world. He lead entrained-flow drying to a breakthrough in the Anglosaxon market. Later on, he sold his company to GEA, today called Bar Rosin Gea. In 1980, he formed the Atritor Limited. The company is now leading in innovative industrial applications of the so called Dryer-Pulveriser (combined drying and pulverization unit). He introduced the audience to this business, together with his sales director, Andrew Rigg.
“The outstanding pioneer work which represents the Rosin-Rammler-Sperling-Bennet distribution should be equally a commitment and a challenge for us”, Prof. Dr. Klaus-Dieter Barbknecht, rector of the TU Bergakademie Freiberg, said. “The requirements have changed, have become more complex. We are now at the beginning of the transition from a linear economy to the circular economy, the most urgent challenge of our century. To be successful, we need our resource university to have at least the same engineering spirit and creativity in these crucial areas of research as Paul Rosin, and later on his son Sebastian Rosin, have possessed.”