Searching for the next generation of process engineering experts – between science, courage and hands-on work

About Christian Gäbelein

What brought you into the brick industry?

Christian Gäbelein: I studied mechanical engineering and after graduating I started working as an operations assistant at Braas, a company that manufactures pitched roof products, primarily concrete roof tiles. Looking back, it was a classic career path with moves and promotions every few years: to operations manager, plant manager, production manager for northern and finally western Germany. I really enjoyed the changing areas of responsibility and the growing responsibility.

Was that during the construction boom in the early 1990s?

CG: Yes, I started right in the middle of reunification. To meet the enormous demand, Braas built new factories, expanded others and invested wisely in the capacity and rationalisation of what were then 21 concrete roof tile and four roof tile factories. It was an exciting time and a very instructive one, both professionally and personally. Braas always gave young people the opportunity to take on responsibility. After one to two years of training, it was possible to be promoted to plant manager. I wouldn’t want to have missed those eleven years.

But no boom lasts forever. The subsequent market decline was drastic, with sales falling by ten per cent year after year. I learned an important lesson for businesses from this period: fixed costs, fixed costs, fixed costs.

At that time, I had already been wanting to start my own business for quite some time. The structural adjustments that followed the crisis and the resulting sharp decline in success stories were the final deciding factors.

I have remained in touch with many people from that time. I still visit my first boss once or twice a year when I am near Würzburg, and I am on friendly terms with many former colleagues.

What was the next step?

CG: After that, I founded a sole proprietorship and worked for various companies as an external contractor for a few years, providing technical consulting, implementing and coordinating projects. When Braas had to streamline operations at its roof tile factories, I was also given projects to increase technical efficiency. This involved classic operational analyses, i.e. identifying bottlenecks, downtime and waste in production.

So you already had experience in optimising brickworks before Keratek?

CG: During this project work, I was still working purely as a mechanical engineer. I still knew relatively little about thermal process engineering, drying and firing technology. However, I found roof tile production extremely interesting due to the more complex technology involved. The knowledge of materials science I had acquired during my mechanical engineering studies would also prove useful later on. But as an employee at Braas and later as a contractor, process engineering played a subordinate role. In this respect, concrete is somewhat less complicated than ceramics. In addition, my main focus as plant manager and later as a contractor was not on the technical side, but on the organisational and human side. Plant manager is a management job.

Joining Keratek

How did you come across Keratek?

CG: Through a tip from a good friend, Frank Kordes. I know him from my time as regional production manager at Braas in Petershagen and later from several projects in the brick industry as a self-employed person. He drew my attention to an advertisement in Ziegelindustrie International by Karl-Heinz Brakemeier, who was looking for a successor for Keratek. I was intrigued and got in touch with him.

How did you manage to get started without any major process engineering knowledge?

CG: I worked very closely with Mr Brakemeier for over three years and paid close attention. He is an outstanding process and plant engineer. Very few people have mastered the subject at this level. Fortunately for me, he was happy to share his knowledge and I was able to learn a great deal from him. Not only about process engineering, but also about how to deal with customers. Because Keratek was small then, as it is today. It was also Mr Brakemeier who put me in touch with the IZF and the FGZ, the research institutes of the brick industry.

Three years is a long apprenticeship. Is heavy clay process engineering such an arcane art?

CG: It’s not rocket science, but it’s not trivial either. There aren’t many experts left who are at Brakemeier’s level. My colleague Wolf Reschke, who has decades of experience in various companies, most recently at Lingl as head of process engineering, is one of them. There are a few other experts whom I have come to know and appreciate through my involvement with the FGZ, for example. I consult with them when in need of advice or a second opinion. It often takes a bit of courage to try something new. This is regularly reflected in our products and services.

About Keratek

Is this expertise a unique selling point for Keratek?

CG: In a way, yes. We are the only office specialising in heavy clay process engineering and, in addition, we are a supplier-neutral engineering office. We carry out kiln and dryer measurements and prepare energy balances and concrete optimisation proposals for both, without being bound to any plant supplier. To my knowledge, this combination is unique.

What exactly do you do at Keratek?

CG: Keratek has three main areas of activity. The first is classic plant engineering, specialising in conventional circulators and, in particular, our turbo block. However, we do not simply offer the units on the market, but always within the framework of process optimisation. Normally, this is always preceded by process engineering consulting.

The second pillar consists precisely of this consulting in the form of furnace measurement, dryer measurement, energy balance reports and everything that goes with it, right down to recommendations based on this. In the best case scenario, this results in a plant construction order. That doesn’t always happen, but it often does.

The third pillar is classic project management for large-scale projects. Over the last five years, I have carried out two major projects with a refractory manufacturer. One involved the construction of a new tunnel kiln with the aim of increasing performance while reducing energy consumption, expanding storage areas, water retention and hall extension. The budget was in the double-digit million range. For three years, I managed every single step without selling a single screw or providing a minute of process engineering consulting. It was an extraordinary project and an excellent collaboration with the customer’s project team.

How is Keratek’s business doing currently?

CG: When Wolf Reschke started here in June 2020, we both hoped to be able to work a little less. That’s why I was looking for a partner and why Wolf Reschke wanted to start at a small company. The end result was that we both continued to shoulder a considerable workload over the past three years. Demand for process engineering consulting with a view to increasing efficiency has risen significantly as a result of higher energy prices in 2022 and the slump in brick sales markets shortly thereafter.

This year is a little quieter, which is quite welcome. Of course, we are continuing to pursue new business and are meeting demand from existing and new customers.

There is still pressure to act in the industry due to rising CO₂ prices as a result of the corresponding regulations. We must take action together here, otherwise we will see the industry go down the drain. And nobody wants that.

The energy future of the brick industry

How do you see the brick industry moving towards climate neutrality?

CG: First of all, we have to acknowledge that implementing the upcoming transformation concepts towards climate neutrality will simply be expensive. In addition to the market situation, this is an additional burden for brickmakers.

The first step in any transformation concept is always to increase efficiency. Alongside the realisation that hydrogen combustion is technically feasible, this is one of the most important findings of the hydrogen tunnel kiln project (H2TO) in which Keratek is involved.

The real sticking point with H2TO, however, is that there will be no economically available, i.e. affordable, hydrogen in the foreseeable future. Furthermore, all the effects in production lead to the same conclusion: igniting the hydrogen produced afterwards does not make sense from an energy and economic point of view.

That is why it is imperative to optimise the entire process first. But even if the plant is completely optimised, it will still be a very long time before hydrogen can be used sensibly as a fuel for the production of building ceramics. The Ariadne study of the Copernicus project predicts a price of 12 to 15 cents per kWh even in optimistic scenarios.

If energy becomes significantly more expensive, what options do brick manufacturers have?

CG: One solution is to build up the capacity to produce it themselves and make it reasonably stable and available. Many brick manufacturers are trying to obtain permits for wind turbines or are investing in their own PV systems. Their problem is often that they have to bear the grid connection costs themselves. This is also an obstacle to efficient energy production and use.

What do you see as the most plausible option for climate-neutral brick production?

CG: In my opinion, the concept of hybrid brickworks operation, as presented by Prof. Christian Schäffer in ZI 6/2015 and 7/2015, is the right approach during the transition period.

We have to differentiate between products. Backing bricks (HMZ) currently perform quite well in terms of energy consumption. We are talking about approximately 200 kWh per tonne of dried and fired goods after optimisation. This value is due to the porosity agents, which provide part of the firing energy. Of course, they also emit all kinds of gases, including CO₂. Many backing brick mixes in southern Germany also have a high lime content. Lime burning requires a lot of energy and also produces CO₂. At an HMZ plant, there is a good chance of making the processes reasonably climate-neutral through process engineering and electrification. All that remains are the emissions from the raw material and perhaps some emissions from sub-processes that cannot be completely covered by green electricity.

So, is it technically possible to achieve largely climate-neutral production?

CG: Basically, yes, with electric auxiliary heating via circulators and decoupling of the kiln and dryer. I once heard a nice and apt phrase at a seminar in England on the basics of brick firing: ‘A tunnel kiln is not a source of free energy.’ A tunnel kiln does not produce energy, it only consumes it. If warm air is extracted from the cooling zone at any point for other purposes, it is then missing in the kiln. It would be better to instead treat the kiln as a pure heat exchanger, extend it and decouple it from the dryer.

This also makes sense because drying is a low-energy process that requires no more than 200 degrees Celsius and often less. The possibilities of low-energy drying have now been very well researched. It can be electrified and, if green electricity is used, carried out in a climate-neutral manner.

What about the kiln?

CG: It’s a little more difficult with the kiln. For HMZ, I believe it is still reasonably feasible due to the comparatively low amounts of energy involved. Here, I see the greater challenge in the process-related emissions. Biogenic porosity agents from renewable raw materials can still be used at the moment. But the question remains as to how long this will still be permitted.

Is the transition more complex for other product groups?

CG: Yes, because the energy consumption is many times higher. For clinker and roof tiles, we are talking more about 700 to 1,000 kWh per tonne. Supplying this energy from electrical sources to a standard tunnel kiln load in a two-metre-high kiln poses a process engineering challenge. To do this, I have to move the atmosphere. In addition to reducing the size of the ceiling and edge gaps, radiation shields may also be an option. It would also be conceivable to form flatter loads in the direction of roller kilns. However, this results in other losses that need to be optimised, and the throughput is lower.

In any case, I believe that two things are emerging in development: electric heating and combustible gases such as synthesis gases, wood gas, etc. The problem with this is reaching the required temperatures. The known green gases have too low a calorific value. The building ceramics industry faces fewer challenges in this respect than refractory manufacturers, glass manufacturers, etc., who have significantly higher temperatures.

How do you assess the situation for brick manufacturers?

CG: The goal of climate-neutral production is clearly defined, even if the path to achieving it is not yet clear. What is clear is that investing in efficiency has never hurt anyone. Higher efficiency is definitely a competitive advantage.

I believe it is right to do everything possible to become climate-neutral. Not only because the EU requires it, but because it simply makes ecological and economic sense.

The future of Keratek

What does the future hold for Keratek?

CG: We are looking for reinforcements with the aim of training a potential successor. I turned 60 last year and would like to work less when I reach the statutory retirement age. I enjoy my job, and there are many good and nice people in the brick industry who have become friends over the years. I can imagine continuing at least the consulting and project management business.

For my colleague Dr Reschke, that time will come this year. However, he will continue to work a few days a week after he retires.

What and who exactly are you looking for?

CG: Wolf Reschke and I would like to pass on our knowledge and customer relationships. I believe that we have a wealth of experience in application-oriented ceramic process engineering going far beyond what is taught at university. It is very important for the industry that this know-how is passed on.

The ideal candidate would be a middle-aged person with knowledge of process engineering and/or ceramics who is willing to learn and take on entrepreneurial responsibility for a small, well-run and established company. We enjoy a stable customer base with many regular customers and, I believe, a very good reputation. The work is interesting and exciting, but as managing director you also have to be willing to lend a hand, for example in plant construction. With its focus on process engineering consulting, Keratek is not necessarily dependent on the sale of plants, which reduces fixed costs and makes management easier. Nevertheless, I am convinced that modern process engineering plants from KERATEK will continue to play an important role for many years to come.

Dear Mr Gäbelein, thank you for talking to us.