Hager + Elsässer GmbH as we know it today is the history of two pioneers in the field of water treatment: Philipp Müller and Hager + Elsässer.

Philipp Müller GmbH was founded in 1896. Over the years, the company developed from a manufacturer of heating systems to a leading water treatment company. From the start, large-scale plants, such as water treatment plants for power stations, waste water treatment plants for pulp and paper mills and the food industry were our main focus. Another major sector of activity was water treatment for municipalities. In 1967, Philipp Müller was acquired by the French company Degrémont.

Hager + Elsässer GmbH was founded in 1932 and became a market leader thanks to its visionary gift for developing and marketing state-of-the-art process technologies. In 1975, Hager + Elsässer GmbH was acquired by Energie- und Verfahrenstechnik GmbH (EVT). Acquisition of the activities of Permutit GmbH Berlin allowed Hager + Elsässer to become more deeply involved in the large-scale plant segment. In 1990, EVT – and thusHager + Elsässer – were acquired by a new partner, the former GEC Alsthom. 

Hager + Elsässer was bought by Philipp Müller GmbH in 1998, and the merger in the following year with Philipp Müller Hager + Elsässer GmbH (PMHE) gave rise to a company with a tremendous spectrum of experience in plant engineering, process engineering and customer service for water treatment plants in all markets and industries.

In 2001, the industrial business was spun off from Degrémont to Ondeo Industrial Solutions, which in 2002 led Philipp Müller Hager + Elsässer to be renamed Ondeo Industrial Solutions GmbH.

Another change of shareholders came in 2006. The company, now part of the Stulz Hager + Elsässer Group, has changed its name back to Hager + Elsässer GmbH, and is looking confidently ahead to the future in a medium-sized business environment.