Which operator is not familiar with them – large stockpiles of surplus aggregates, unusable filler fractions, sludges from washing plants or fines from the recycling of demolition materials. During the processing of sand and gravel deposits, fines <63 µm are washed out, dewatered and then landfilled or flushed back into the deposit. Due to the different genesis, considerable quantities of commercially unusable fine sands are also produced, e.g. in Netherlands, Northern Germany, Poland and the Baltics, which also have to be returned to the deposit and incur additional material handling costs. However, large quantities of crushed sands are also produced by the deconstruction and recycling of building materials, the commercial use of which is currently only possible to a limited extent. The amendment of the circular economy also increases the pressure to make previously unused residual materials usable and to use recycled building materials. These secondary fractions take up valuable space on the company premises or have to be landfilled. However, the materials can be valuable components for the production of artificial aggregates.
According to the standard, artificial aggregates are aggregates of mineral origin that have been produced in an industrial process under the influence of thermal or other modification or from recycled material. For example, artificially produced, crushed and uncrushed, dense and porous aggregates from fly ash or slag. Another efficient and economical option is the agglomeration process in the pelletizing disc. With this process, residual materials can be processed into high-quality construction aggregates.
The preconditioned feed materials are homogenized with binder (usually cement) in a mixer and prepared for the pelletizing process by adding water and then continuously fed to the pelletizing disc. By varying the machine parameters (speed, inclination and rim height) of the pelletizing disc, artificial aggregates can be produced precisely in the desired range of product sizes. By using cement as a binder, thermal drying can be dispensed and the green pellets cure independently on a stockpile. After the pellets hardened, they are able to be further processed in a crushing and classifying plant and used as artificial aggregate for concrete production. Due to the low bulk density of the agglomerates, these can also be used as lightweight aggregates.
The SCARABAEUS transfers particularly non-usable residues into usable, valuable and high quality products. This transfer increase environmental protection and sustainability coupled with quality standards and economy profit.
HAVER Engineering awaits you at any time for initial feasibility studies. With little effort, tests on the general suitability of the residual materials can be carried out in the pelletizing pilot plant, recipes can be optimized and the necessary plants can be designed. On the basis of the basic engineering, a first profitability analysis can be carried out. Subsequently, HAVER & BOECKER NIAGARA takes over the further planning for an efficient plant construction with proven process technology.
Haver & Boecker Niagara is the global brand for processing technology! With its main locations in Germany, Brazil and Canada, it combines the many years of experience as well as the success of the Haver & Boecker and W.S. Tyler brands with worldwide engineering and application know-how. We support our customers in meeting tomorrow’s challenges with a world-class portfolio of efficient and profitable machine technology.
Our global network of experience allows us to solve the most unique problems.
Florian Festge, Haver & Boecker Managing Partner
