4. Optimization of Second Step Scrap Iron processing line _ GISEMENT
Second Step Scrap Iron is a mix of scrap iron with plastic, textiles and foams. Non-metallic material presence in this sub-product is not in conformity with the extraction process role. Scrap merchant who purchase this mix consider that scrap iron represent only 40% of the total mass of this mixture. Therefore they buy it cheaper than first step scrap iron,considering they have to implement another selecting step. Improvement of second step scrap iron only implies a technological change on the treatment chain. It consists in a structural optimization of the present implantation. At the present time, the extraction process for this mixture is the following one. An overband is placed above the main conveyor belt. Scrap metal is attracted by the overband and it falls in a kind of funnel to get to another conveyor. At its end, it falls again on the ground. The issue of this specific material is that when it is extracted from the global treatment chain _ plastics, textiles, foam and fragments of wood, hooks metallic pieces are dug up too.
First of all, it was obvious that the present Second Step Scrap Iron mix
quality can be improved. A manual selection had been
implemented in the reception area under the exit conveyor.