If the term “industrial quantities” is taken to mean an annual tonnage of 50,000 tonnes, which is certainly not enormous for building materials, this quantity could be produced when a licensee is prepared to invest in such an industrial plant. We, together with machine and plant manufacturers, are in the process of designing a first industrial reference plant of this size.
Commercially available quantities of Celitements require an expensive industrial production plant. However, the decision to build such a plant has not yet been taken.
Any investment decision in what we will call a first industrial reference plant, to differentiate it from the existing pilot plant, will be based on three cornerstones:

– A dependable mechanical and plant design concept backed by the plant constructors and manufacturers of the requisite technology. This can only be accomplished when the entire mechanical, process and control technology and the storage and utilities infrastructure for an industrial plant as well as the appropriate systems for production and quality assurance have been fully defined. This is well on the way, one might say on the “final lap”, but is not yet completely finished.
– Before new substances can be placed on the market they must fulfil all the legal chemical preconditions (REACH registration). This we achieved in 2018.
– The product must be marketable from the technical and price aspects so that potential customers are able to use it in practice in fairly large quantities immediately after the first industrial plant comes into operation. This process, i.e. preparation of the market, has not yet been completed. We are working on it with numerous innovators from a wide range of applications. Even the development of “simple” plaster systems based on new types of cement can easily take 12-18 months with the producer. This preparation work must have been completed when the industrial plant comes into production

Fulfilling all three minimum requirements for the development of a completely new binding agent system is a tedious and expensive process.

We are breaking completely new ground in many areas, which means that we are faced with a great deal of hard work. Perseverance and patience is needed for such new developments, especially in the building materials sector.

Relatively large capital investment in machinery and plant is always needed at first just to be able to embark on industrial-scale development of building materials and, later on, production. It was only when our pilot plant was commissioned at the end of 2011 that it was possible to continue the development of the production process, which had previously only been tested on a laboratory scale, until it is ready for industrial use. The technologically most complex and demanding process step is the mechanochemical (“tribochemical”) activation grinding.

Choosing the optimum grinding technology for this purpose required very extensive and time-consuming preliminary trials with a wide range of grinding systems. It was only in 2013 that a vibrating tube mill was installed in the pilot plant. This was chosen because the energy input and the stressing period as well as the type of stressing can be varied very flexibly. This made it possible for the first time to produce test materials in fairly large quantities (approx. 100 kg per day) and carry out realistic tests on the product properties. In the meantime we have identified the eventual grinding system that is also intended for the industrial plant. Such a system is now to be integrated into the pilot plant as part of the extension of the plant. This means that the most important component in the Celitement production process has been conclusively defined. The dimensioning and design engineering for the complete industrial plant to the stage where it is ready for placement of an order are well advanced but not yet finally complete.

We designated the plant completed in 2011 on the North Campus of the Karlsruhe Institute of Technology in Karlsruhe as the “pilot plant”. It is not intended for producing industrial quantities of Celitement. This is to take place in the “industrial reference plant”. The pilot plant is already in existence but the decision to build an “industrial reference plant” has not yet been made.

The first industrial reference plant has been planned and designed for a maximum annual capacity of 50,000 t Celitement. This design capacity was chosen after evaluation of the market research. When such a plant has reached industrial operational readiness a high level of utilization and therefore cost-effective operation of the plant can be ensured very quickly. Such a plant size also ensures technical scale-up to even large licensed projects.

It will be possible to make a relative rapid decision on investment in the first industrial plant as soon as the extension to our pilot plant has been commissioned and there is correspondingly positive feedback from the production trials with selected innovators that will be then possible with the larger quantities of material. Assuming a construction and commissioning phase of about two years, entry into the market cannot be expected before 2024. To explain the individual development stages from the first idea to final industrial implementation reference should be made to the following designations of the TRLs (Technical Readiness Levels). The figures given in brackets represent the respective periods involved:

TRL 1: Study of the functional principles (1994-1996)
TRL 2: Description of the product/technology (1997-2000)
TRL 3: Functional verification of the product/technology (2001-2004)
TRL 4: Experimental set-up on a laboratory scale (2005-2008)
TRL 5: Design/construction of the pilot plant (2009-2013)
TRL 6: Test operation in the pilot plant (2014-2017)
TRL 7: Normal operation of the pilot plant (2018-2021)
TRL 8: Planning/construction/commissioning of the first industrial reference plant (2024-2026)
TRL 9: Normal operation of this reference plant and issuing of further licences (from 2026)

The validation, scale-up and transfer of the production method for a completely new type of binding agent requires a stepwise approach because of the varied technological and economic challenges. The plant size of 50,000 t/a represents a good compromise between the CAPEX (capital expenditure) and OPEX (operating expenditure) costs. Small plants that consist only of components and building elements with special sizes that possibly have to be manufactured individually have very high specific CAPEX costs. It is better to make use of machine and plant technology that corresponds to standard equipment sizes already established in the market. Another scale-up step would also probably entail a completely new design. A 50,000 t/a plant makes it possible, in principle, to use absolutely any highly scalable individual units. Also, because of the lack of building regulation approval for Celitement, this binding agent cannot be used immediately in structural concretes, which means quite simply that the most important mass application is missing. However, the chosen production quantity is sufficient to cover all the other planned applications. To plan on too large a scale is risky while too small a plant might not be able to service the customer’s requirements adequately.

Celitement cannot be produced with the plant technology used in existing cement plants. However, what will really make sense is the integration of Celitement plants into existing cement or lime plants to make use of the infrastructure that is already there (quarry, dispatch system, incoming goods department, shop, workshop, laboratory capacity, administration, etc.). We are assuming that the first industrial plant will be a “brown field” plant, i.e. it will be integrated into an existing production site for binding agents. “Green field” sites that are completely independent in all sectors are only likely to be realized at some later date.