F.E. Schulte Strathaus GmbH & Co. KG has won a competition for best scraper.
Dissatisfied with the quality of scrapers on its new conveyor belt system, Danish recycling company Afatek organised a competition. Five internationally renowned manufacturers took part, and German firm Schulte Strathaus, a member of the Fess Group, was declared the winner.
There were no preconditions in the content. Each competitor could choose a belt. The winner would be the entity whose scraper returned the best cleaning results. The measuring method in each case was identical. A second scraper covering only a small section of the 120cm-wide belt was mounted behind each scraper.
“Then we hung a bucket underneath, and after 10 minutes removed it and weighed the contents”, explained Afatek project manager Henrik Juul Rysgaard. The result was easy to calculate on an hourly, daily and weekly basis, he added. Only secondary belt scrapers were tested.
Afatek is a recycling company that processes slag. Annually, 235 000t are processed at the firm’s headquarters in Copenhagen harbour. Waste in Denmark is sorted in various fractions. Even after sorting and incineration, valuable residue can be found in the residual slag, which is what Afatek salvages.
The plant, with 52 conveyor belts, is housed in a 70m-long, 30m-wide tent, which is 11m high at its highest point. In there, said Rysgaard, “it has to be clean”. But that was not the case with the newly delivered conveying system. “We were not happy with the scrapers,” continued Rysgaard. “We wanted equipment which met our demands. And we organised the competition to find it.”
Afatek processes slag with different humidity. That is a challenge for scrapers. The test took place with moist and drier material.
Competition winner Schulte Strathaus said that differences compared to the other competitors’ scrapers were “enormous”. In the test with drier material, it claimed that residue could be reduced more than four-fold compared to the runner-up. Whereas Schulte Strathaus recorded an hourly average of just 3.15 kg, the next best was 12.6 kg. Third place resulted in 13.61 kg, and 51 kg were measured for the fifth and final competitor.
The test with moist material produced similar results. Schulte Strathaus again took first place with 6.75 kg, while second place turned in 19.54 kg. The third place measured 21.38 kg, while the fifth and final place measured 42.9 kg.
Rysgaard gave two reasons for Schulte Strathaus outstanding performance in comparison with the other competitors. Firstly, the German manufacturer chose the belt with the widest variety of material, with granulation ranging from 0mm to 50mm. The other competitors chose belts with finer material.
But Rysgaard considered the segmented pressure roller system employed by Schulte Strathaus to be the main reason for their excellent results. This ensures that the metal carbide strip is always correctly aligned to the belt.
“This pressure roller system is a very good solution particularly when belt tension varies, as in our case,” said Rysgaard.
Now, Afatek intends to retrofit the German manufacturer’s Starclean scrapers wherever it makes sense to do so.