About us

Celitement GmbH was founded in 2009 as part of a collaboration between research (KIT) and industry (SCHWENK Zement KG).

A laboratory and administrative building was constructed in 2011 together with a pilot plant. Test material for practical application tests with the new binding agent are produced in this facility. Product features and recipes can be tested together with selected innovators to develop Celitements up to market readiness.
In early 2020, Celitement GmbH was fully taken over by its shareholder, SCHWENK Zement KG. From having been a SCHWENK affiliated company it became a full subsidiary of the well-established building materials group from Ulm. With the full takeover of Celitement GmbH by SCHWENK Zement KG, the financial resources for further expansion of the pilot plant were provided.

This means that after purely basic research at KIT and a phase of products and process development which was also very research intensive in the past years, Celitement GmbH is now entering the final phase of securing a decision, which has yet to be made, regarding the construction of a first industrial reference plant.

Celitements are high quality hydraulic binding agents which are manufactured using a patented, energy-efficient process. Compared to Portland cement clinkers, they are characterised by a specifically lower use of limestone as main raw material and lower process temperatures in the manufacturing. We develop and optimise these innovative hydraulic binding agents with the aim of creating marketable products, thereby contributing to decreasing the CO2 intensity of cement manufacture. In order to do this, we use the latest analytical equipment and have many years of experience in the field of cementitious material development to fall back on.
Until June 2013, the optimisation of the production process was the subject of a funding project by the Federal Ministry of Education and Research and the project sponsor Jülich entitled: “Celitement - development of sustainable cement”.

2020 - The Celitement GmbH ist taken over by SCHWENK

Celitement GmbH 2.0 - change of the corporate structure of Celitement GmbH

Foto: Schwenk Zement KG Hauptverwaltung Ulm
Foto: Schwenk Zement KG Hauptverwaltung Ulm

Retroactively to 1 January 2020, SCHWENK Zement KG took over all shares of the previous fellow shareholders in Celitement GmbH, in other words the Karlsruhe Institute of Technology and the four inventors as shareholders. From having been a Schwenk affiliated company, Celitement GmbH became a full subsidiary of the well-established building materials group from Ulm.

Celitement GmbH was founded in February 2009 and by autumn 2011 had a pilot plant erected on the KIT site (North Campus, Eggenstein-Leopoldshafen) to develop the process and manufacture test material of the novel binding agent.

As part of a collaboration agreement with the KIT which expired in late 2019, Celitement GmbH continued to develop the manufacturing process based on several patents for these innovative hydraulic binding agents (known as hydraulic calcium hydrosilicate - hCHS).

SCHWENK Zement KG will initially invest in expanding the existing pilot plant. The plans for this are almost complete. This will significantly increase the actual production output. After the expansion has been commissioned, selective innovators will be able to have test quantities amounting to single-digit tonnes. These quantities are still not yet sufficient to construct larger concrete buildings with the innovative binding agent, but will enable large scale practical tests to be carried out in all of the areas of application that have been tested so far.

This means that after basic research at KIT and a phase of products and process development which was also very research intensive in the past few years, Celitement GmbH is now entering the final phase before a decision is made by SCHWENK regarding the construction of a first industrial plant.

For Schwenk Zement KG, investments in Celitement GmbH are not just a logical continuation of their previous innovation and development strategy in the field of development of entirely new construction materials. The takeover of the pilot plant expands the previously already excellent research opportunities at Schwenk Zement KG to include a unique technical pilot plant that includes a very innovative grinding technique among other things.

2013 - Expansion of the pilot plant

Foto Celitement: Lager- und Werkstatthalle im Anschluss der Pilotanlage
Foto Celitement: Lager- und Werkstatthalle im Anschluss der Pilotanlage

As the production capacity of the pilot plant increased, a first expansion to include a storage hall with a workshop area was necessary in 2013. This investment enabled the work processes in the actual pilot plant to be further optimised.

2011 - Completion of the building and the pilot plant

Foto: Markus Breig KIT
Foto: Markus Breig KIT

The pilot plant integrated into the company headquarters of Celitement GmbH was put into operation on 11 October 2011. It has a production capacity of up to 100 kg per day. The pilot plant replicates both of the core processes for manufacture: the autoclave area to manufacture an amorphous CSH phase as an intermediate product and the mill area which contains the grinding technology to generate the final products using what is known as activation grinding.

2007 - Patented Family of Binding Agents

Based on the results of the basic research on the structure and properties of calcium silicate hydrates (C-S-H), KIT patented the principles of the manufacture of the novel innovative binding agent in 2007 under the brand name Celitement®, which was also protected. In 2009, Celitement GmbH received a global exclusive licence based on these basic patents held by KIT.

1994 - Celitement - hydraulische Calcium-Hydro-Silikate

Work has been carried out on hydraulic binding agents at the Karlsruhe Institute of Technology KIT for several years. The focus was and is on tests of the structure and the reactions of calcium silicate hydrates. Very simply put, the manufacturing principle of Celitement consists of a basic principle which is somewhat unusual at first glance:

First you manufacture an intermediate product which is actually very similar to the subsequently desired end product but which is hydraulically inactive because it has already “hydrated” (this is known as the CSH phase). The manufacture of comparable phases is known from aerated concrete and sand-lime brick manufacture. Here, too, comparable phases known as calcium silicate hydrates (C-S-H), the “glue” which gives concrete and mortar their strength, are manufactured in autoclaves.

This hydraulically inactive intermediate product is then “destroyed”, or converted into the reactive (hydraulic) end product (calcium hydro silicate = hCHS phase) by means of special activation grinding. Celitement is therefore created through a tribochemical or mechanochemical grinding process. When water is added (hydration), this hCHS (Celitement) then reacts back to a strength giving C-S-H phase.