Kunda plant ends clinker and trials lower-carbon cement materials

Riho Iskül, manager of construction-materials producer Kunda Heidelberg Materials, the former Kunda cement plant, told Vikerraadio’s Friday interview that Estonia’s industrial policy is broadly in good shape, while odd anomalies remain, including laws that intervene in the market economy. He called promises by some politicians to halt the green transition after taking power a catastrophe for an industry that has invested billions.

The plant, more than 150 years old in a town long built around a single industry, still stands beside a beach and a port. It no longer makes clinker, the part of cement production with the largest CO2 footprint, and Iskül said it should not be described as a full cement works. Clinker now comes from the Slite plant on Gotland in Sweden and the Brevik plant in Norway, a shift he linked in part to the green transition. Kunda’s own clinker line closed six years ago. Its clinker carried about one tonne of CO2 per tonne of product. Material from Sweden is at 0.7 tonnes, and the Norwegian average is under 500 kilograms, about half the old Kunda figure.

With the CO2 price near €85, Iskül said a simple comparison on the carbon price alone would have left Kunda €40–50 a tonne more expensive. He still called the closure the right decision. Some people lost their jobs and less local raw material is upgraded, and the old Kunda kiln was a wet-process plant while dry process is now standard. Even a rebuilt line would have faced a regional surplus: when producers across Europe made clinker, much of it was sold outside the EU to Africa, North America and elsewhere, but the emissions-trading system ended profitable exports and the material has to be used inside the market. He believes delaying the decision would have left the plant in a very difficult position.

Cement remains the largest volume, alongside crushed construction stone from limestone and granite aggregate brought from Scandinavia. A newer, still small line is secondary cement material. Additives replace part of the clinker. Iskül expects that share, tiny in today’s portfolio, to stand out beside ordinary cement within five years. Estonians rarely buy bagged cement and usually order ready-mixed concrete. When Kunda last packed cement, bags were about 1% of output, against about 40% in Lithuania. Saint-Gobain, through Weber, now packs Kunda cement.

Kunda has long substituted oil-shale ash for clinker, with strong results at a time when others used cleaner mixes without additives. Coal-plant ash later became common elsewhere, but supplies are tightening as coal stations close. Demand for secondary materials is high enough that waste from someone else may not be enough and the additives may have to be made. Oil-shale ash is still used, yet the Narva plants are large emitters, reach the market only at very high power prices, and only ash from one unit suits Kunda, which is not enough. Last year the company began bringing volcanic ash, a pozzolan, from Iceland. It must be dried and ground and performs very well. Inside the group, demand for that material alone is on the order of 300,000 tonnes in the coming years, more than Kunda’s whole cement output of about 250,000 tonnes. A third option is calcined clay. The group holds a fairly large clay reserve, trials are done and a decision is pending. The main CO2 release in clinker comes from breaking down limestone. Calcining clay does not do that and leaves a low-carbon additive with strong results.

One lower-footprint grade, EvoBuild, must be 30% below the 2020 footprint. Its price gap is modest, achieved with domestic ash where possible or with dearer volcanic ash. Near-zero-CO2 clinker is a different case. Clinker from carbon capture and storage contains 46 kilograms of carbon per tonne, against a tonne per tonne for the former Kunda product, and Iskül said the price differs by multiples, not by a few tens of percent. The latest capture unit in the region is at Brevik. The Norwegian state contributed heavily. The capture plant cost more than a cement plant, in the billions, and running it is very expensive. Set against a square metre of a finished building, he said the gap is still a fraction of a percent.

He traced the pressure to the EU emissions-trading system, which he placed around 2003, allowing that he might be a year out. Early caps were wide, cement received free quotas, the price stayed under €10 and in 2007 fell to about zero. Alternative fuels and a lower clinker share were enough at first. The bar keeps dropping, and staying viable now means carbon-capture equipment at the plants. If the public has set the rules, he said, the industry has to accept them, including the cost of carbon neutrality.

Employment has collapsed with the process. At the Soviet peak, when almost everything in Kunda was tied to the plant, about 1,800 people worked there. Today there are 63. Machines do the work. Maintenance and transport are no longer done in-house. Iskül said labour cost pushes every producer the same way. Most staff are local to Kunda, some come from Rakvere, and sales and finance sit in a Tallinn office. Labour mobility is basically zero. The workforce is ageing, ready-trained operators are not available from schools, and machinists are trained on site and retained.