Roskilde Sten & Grus uses Lokotrack to produce special aggregates for meeting climate change challenges
Climate change is boosting the innovation of brand-new aggregates types. Roskilde Sten & Grus, one of the leading sand and gravel refining companies in Denmark, has developed an aggregates mix that allows water to penetrate more efficiently during increasing downpours. The new climate change aggregates is becoming more popular, and its primary crushing is done with Metso’s Lokotrack® jaw crushing plant.
“Our new aggregates type allows water to soak through up to three times more efficiently than traditional aggregates. We’ve been developing this product for many years, and our challenge was to find the correct mixture of different rock sizes,” Anders Jensen, CEO of Roskilde Sten & Grus ApS, describes the development of the new aggregates type.
“New Danish legislation requires that aggregates developed for climate change needs must be used in the foundations and parking areas of the state’s construction projects. This means the ground effectively absorbs water so that it doesn’t flow into the sewage network and cause flooding,” Jensen continues.
More than 100,000 metric tons of aggregates to tackle climate change
Roskilde Sten & Grus refines this climate change aggregates and other required varieties from gravel and sand from the former seabed. Over an area of 200 hectares, the company uses 17 crushing, screening and washing plants to produce more than 50 end products – between 1.5 – 2 million metric tons a year.
There are aggregates types for everything: foundations, concrete and asphalt production, and building golf courses. Each year, the company produces approximately 100,000 metric tons of climate change aggregates, and demand for it is growing quickly.
“During the development phase for the new aggregates, we carried out multiple tests. The recipe for our water-permeable product includes crushed stone of 0–32 mm and a small quantity of fines. However, most of its structure consists of larger crushed stones,” Anders Jensen says.
“The situation today is quite interesting for a producer. In Denmark, climate change has forced us to replace certain end-products in our portfolio with brand new ones. As entrepreneurs, we need to stay aware of the trends and their fluctuations.”
A mobile plant with an hourly output of 350 metric tons
The company’s newest combination of a Lokotrack LT106 jaw plant and a Jonsson 6800 cone-screen plant produces climate change aggregates with an hourly capacity of 350 metric tons. P.J. Jonsson och Söner AB has been part of Metso group since July 2018.
A wheel loader feeds 0–300 mm gravel into the LT106, which has a closed side setting of 65 – 70 mm. After primary crushing, the material goes to the Jonsson cone-screen plant.
“Metso’s LT106 has worked well, and we’re very pleased with it. Apart from the production capacity, its fuel consumption was a positive surprise. It only consumes 14 liters of fuel per hour,” says Production Manager Kim Østergaard.
Reconstructing nature with landscaping
Roskilde Sten & Grus was founded by Jørgen Jensen in 1980. His son Anders is currently the CEO. The company employs about 40 people.
At the Roskilde location, the company has gravel reserves for 10–15 years. In addition, Roskilde Sten & Grus has production facilities at four different places in Denmark.
After production, the gravel sites are carefully landscaped to match the original natural surroundings. There are plenty of uses for the site.
“Because Copenhagen is so close, Roskilde is becoming more popular as a residential area, so good building land is always required. The gravel pit can later be turned into a comfortable residential area, with greenery and a lake view,” Anders Jensen points out.