On September 4, 2026, there was a special occasion to celebrate at Cornelsen: The Cornelsen Group looks back on 25 years of company history. Employees, long-standing partners and colleagues, as well as guests from politics, business, and science, gathered at the headquarters in Essen.
The morning began with a focus on the official anniversary. In addition to a review of the company’s development, the main topics discussed were those that will concern us today and in the years to come: the protection of the water resource, the role of new environmental technologies, and the question of how to accelerate the transfer of innovations from research and development into practical application.
Exchange with politics, business and science
Among the guests in Essen were Alexandra Landsberg, Head of Department at the Ministry of Environment, Nature Conservation and Transport of the state of North Rhine-Westphalia, Julia Klewin, Deputy Mayor of the city of Essen, as well as Matthias Hauer MP, directly elected Member of the Bundestag for Essen III, Parliamentary State Secretary for Research, Technology and Space and Chairman of the CDU Essen.
Also following the invitation were Fabian Schrumpf, MdL, member of the North Rhine-Westphalia state parliament for the Essen IV constituency and chairman of the CDU parliamentary group in the city council of Essen, Frank Müller, MdL, member of the North Rhine-Westphalia state parliament for the Essen II constituency, and Julia Kahle-Hausmann, MdL, member of the North Rhine-Westphalia state parliament for the Essen III constituency.
Among those from business and science were Gerd Kleemeyer, President of the IHK in Essen, and Prof. Dr.-Ing. Christian Doetsch, Head of the Institute at the Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT.
Together with Dr. Ing. Martin G. Cornelsen, founder and managing director of Cornelsen Umwelttechnologie GmbH, the guests first looked at the company's development and the importance of medium-sized technology companies for the region and beyond.
As the second mayor of the city of Essen, Julia Klewin focused on Essen as a business and innovation location and on the role of companies that have their roots in the region and continue to develop internationally from here. Subsequently, Matthias Hauer spoke about research and technology as well as the framework conditions that are necessary for innovations to emerge in Germany and find their way from development to implementation.
Afterwards, there was a joint discussion with Dr. Martin Cornelsen, Julia Kahle-Hausmann, Gerd Kleemeyer and Prof. Dr.-Ing. Christian Doetsch. The focus was on the transfer between science and industry, the prerequisites for successful innovations, and the importance of modern environmental and water technologies for the economic location of Germany. Daniela Ulbing conducted the official part of the event.
From Essen to the world
25 years of company history can hardly be reduced to a single moment. From a company in Essen, an internationally active group has emerged over the years, which today operates with teams and locations in Germany, Great Britain, Sweden, the Netherlands and the USA. The origins remain in the Ruhr region.
Technologies were developed and projects implemented here; over many years, partnerships with companies, research institutions, and other partners were established. One of these connections has existed for many years with the Fraunhofer Institute UMSICHT. The joint work resulted in, among other things, the patented PerfluorAd® technology for treating PFAS-contaminated waters, a solution from the heart of the Ruhr region that is now used internationally.
This development pretty well describes what Cornelsen has been all about over the past 25 years: not leaving technical ideas to stand in the development stage, but developing solutions that can be put into practice under real-world conditions.
Many companions, a common history
The anniversary was also an opportunity to bring together the people and organizations that have supported Cornelsen along the way. Research partners, customers, companies, institutions, and personal mentors have all contributed their share to the development over the years. Some of them have been accompanying Cornelsen for a long time, others have joined in recent years.
Bringing many of them together in Essen on one day made the anniversary something special. In addition to the official program, time was deliberately left for personal conversations, new contacts, and the shared exchange of ideas.
After the official part of the event ended, the employees continued to celebrate together. Colleagues from the international locations also came to Essen to join in the festivities. By now it was clear how much Cornelsen has changed in 25 years. A story that began in Essen has long since become an international one.
The day in retrospect
A short compilation of the anniversary day in Essen, featuring the voices of our guests and impressions of the location.
The gaze continues
The challenges that Cornelsen is currently addressing are not getting any smaller. PFAS, increasing demands on water treatment, new regulatory requirements, and responsible management of the water resource present concrete challenges for industry, municipalities, and operators. At the same time, the demands on technologies and treatment concepts are increasing.
For us, this means developing existing solutions further, pursuing new approaches, and implementing technologies where they are needed.
September 4th was a good moment to take a look back after 25 years. But above all, it was a day with many good conversations, familiar faces, new contacts, and our international team in one place.
Many thanks to all the guests, partners, supporters, and employees who celebrated this day with us, and to all who were part of the past 25 years of Cornelsen. We look forward to what comes next.
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