Waste used in the cement industry

For the first time in Lithuania and the Baltic States, mixed municipal waste collected from residents is being utilized in the cement industry.

Waste becomes an alternative fuel used in cement production, thereby reducing the consumption of fossil fuels, emissions of greenhouse gases into the atmosphere, and the amount of waste incinerated in cogeneration power plants.

Mixed municipal waste is also used as raw material because the ashes of a special waste mixture formed during combustion enter the clinker composition, allowing for a reduction in the use of natural resources such as clay, sand, and limestone.

Better waste management

The operator of the Vilnius Mechanical and Biological Treatment (MBT) plant, UAB Energesman, plans to produce approximately 80,000 tons of special SRF (Solid Recovered Fuel) product per year, which has already been used at the AB Akmenes cementas plant. Energesman has already invested EUR 2 million in the production and certification of the new product.

“This is an excellent example of a circular economy, where waste is reused in the production of new products. We were the first in Lithuania and the Baltic States to certify the technological process for mixed municipal waste because waste used in production must meet high-quality criteria. We mix different types of waste in certain proportions, which need to be separated from mixed waste streams, shredded to the required size, and dried.

We are pleased to have achieved this. It is an excellent opportunity to utilize soft plastic products – various packaging materials for which recycling options are currently limited. This is a real challenge for the European Commission in achieving its goals in the field of plastic recycling,” says Algirdas Blazgys, CEO of Energesman.

Energesman is the first company in Lithuania and the Baltic States to receive certification from Bureau Veritas, allowing the production of a special SRF mixture from waste streams and its supply to the cement production process in Naujoji Akmene.

“The Lithuanian waste management system has become smarter and has gained many advantages,” says Gintaras Denafas, a professor at the Faculty of Chemical Technology at Kaunas University of Technology, who researches waste management technologies.

AB Akmenės cementas is refusing fossil fuels

AB Akmenes cementas has invested around EUR 25 million in new equipment, which allows for the acceptance and use of a larger quantity of SRF product from waste and its use in cement production, thereby reducing the use of fossil fuels in production.

It is planned that by the end of 2027, up to 90% of coal will be phased out, replaced by alternative fuel – SRF made from waste. This year, the plant plans to increase the use of SRF to 75%.

“We are the only cement plant in Lithuania and part of the German company SCHWENK, focusing on product quality, supporting personnel, implementing investment projects, and rational solutions to environmental issues. Therefore, it is important for us to work more sustainably, abandon fossil fuels, reduce the use of natural resources, and move towards a circular economy. This will have a significant impact on the entire Lithuanian economy,” says Arturas Zaremba, General Manager of “Akmenes cementas.”

Cement is made from clinker, which is made from clay, limestone, iron oxide-containing materials, and sand. The SRF waste mixture accounts for about 0.1% of the clinker, which is later ground with additives to produce cement.

As noted by Denafas, the greatest environmental advantage of the SRF product is reducing the impact on the greenhouse effect.

“The SRF fuel consists partly of paper, wood, and textiles – biogenic materials formed during photosynthesis – so the carbon dioxide emitted during SRF combustion less disrupts the carbon balance in nature and has a lesser impact on the greenhouse effect,” says the professor.

Already used in other countries

“Solid Recovered Fuel (SRF) is already successfully used in other countries as well. In Sweden, on the island of Eland, a cement plant uses this fuel in clinker and cement production. It can also be used as a raw material in the chemical industry to extract compounds that are traditionally derived from oil,” says Professor Denafas.

According to data from the Ministry of Economy and Innovation, only about 4% of waste in Lithuania is reused in production. This is three times less than the circular economy share of the European Union, which is 12%.

Because Lithuania does not recycle the amount of plastic set by the European Union, it pays the European Commission EUR 13 million in plastic tax annually. For waste used in cement production – including non-recyclable plastics – to be recognized as raw material and no longer subject to tax, a decision by the Ministry of Environment is required. Such a decision would be more sustainable and environmentally friendly, reducing the amount of waste entering cogeneration plants because some of it would become part of the SRF.

The production of SRF products is one of the parts of the EUR 10 million investment program by Energesman. The plant has also invested in new equipment to increase glass sorting to 10-11 thousand tons per year for further recycling.

The Vilnius Mechanical and Biological Treatment plant managed by Energesman sorts mixed municipal waste from the entire Vilnius county, which includes 8 municipalities: Vilnius city and Vilnius, Trakai, Elektrenai, Ukmerge, Svencionys, Salcininkai, and Sirvintos districts. The plant sorts about 220,000 tons of waste per year.