Purkumerkki quietly crushes concrete with Lokotrack® Urban

Crushing done with significantly lower noise and dust

“The combination of quiet operation, a capacity of more than 200 metric tons, the 17-liter consumption and a magnet that effectively removes concrete reinforcements makes this must-have equipment at all our recycling sites.”

The benefits of this quiet and low dust crushing plant have been experienced first-hand by Mikko Mähönen, the Managing Director of the Purkumerkki Oy demolition company from Iisalmi, Finland. It took him just two working days to form his opinion of this Lokotrack® Urban LT96 plant that was rented from Rotarent.

“All those dreams about demolition buckets are history, because I can now work with Metso’s Lokotrack. Obviously, we’re going to have to purchase this crusher to complement our fleet,” Mikko Mähönen sums it up.

Clean crushed rock from building waste  

Purkumerkki’s first site with this noise- and dust protected Lokotrack Urban was quite demanding. At Kajaanin Romu, they found a huge pile of recycled concrete from a demolished school building waiting for them. The pile included an exceptional number of concrete steel re-enforcement, as well as thicker steel bars and slabs.

Being an expert operator, Mikko Mähönen used the bucket teeth to sort out steel before pouring the material into the rubber-lined feed hopper. By using the tilt, the feed was precisely guided to the feeder and then on to the crusher.

The Nordberg® C96 jaw of the Lokotrack has no problems handling demolition concrete. For the crushing, a 74-mm setting was used, meaning that the resulting end product was clean and certifiable crushed aggregate between 0 and 90 mm. The steel bars did not bridge over the crusher, and the effective magnet removed reinforcements extremely precisely.

At this worksite, the separated steel was swiftly recycled at the facility next to Kajaanin Romu. Clean crushed concrete is used onsite as artificial fill to expand the recycling fields.

Quiet crushing with more than 200 metric tons

The full noise encapsulation of the jaw crusher absorbed the crushing noise so effectively that the only sounds heard at the site were the hum of the diesel engines of the Lokotrack and the excavator, as well as the chink of the steel bars falling onto the pile.

An official crushing noise measurement was taken at the same site, and it proved that the operation noise was significantly lower than with conventional crushers. According to the measurements, the area within 3–5 meters of the machine was the only zone in which the noise exceeded 85 dB, and where hearing protection were needed.

Thanks to the encapsulation of the crusher and the covered conveyor, there was practically no dust during concrete crushing, eliminating the need for the standard high-pressure spraying.

“We’re just learning to use the machine, but we’ve already reached a capacity of more than 200 metric tons per hour and 3,000 metric tons in a 12-hour shift. Who knows where we’ll end up next week, when we start proper work with a machine that is now more familiar to us?” Mikko Mähönen muses.

Recycling instead of high landfill costs

Purkumerkki is a contracting company that was founded in Iisalmi in 2015. It focuses mainly on the demolition and recycling of schools, apartment buildings and industrial buildings. Its operating area covers everywhere from Helsinki to Rovaniemi.

The company has grown quickly every year and has now become one of the major operators in the field. Currently, the company has 15 employees.

“We are renowned in the field for precise recycling of demolition materials, safe operating procedures and an appropriate fleet. We have great partners in our recycling processes, so we can minimize the amount of residual waste,” Mikko Mähönen points out.

“Bringing any demolition material to a landfill can easily cost 10–20 euros per metric ton, so recycling is the way to go.”

During the fall, Purkumerkki is finalizing the construction of its own recycling center in Iisalmi. At this center, it will be possible to separate concrete, wood, felt, insulation wool, metals and mixed waste from demolition materials.