Montirone Plant

In the Montirone production plant (BS) the following processes are carried out:

  • Preparation, selection and refining of materials for scrap casting and refining to produce secondary aluminium;
  • Recycling of waste and scrap from Raffineria Metalli Capra's Castelmella Plant and from third parties.

The plant contains two technologically-distinct systems that allow 100% recycling of the aluminium that is contained in scrap, in material coming from the dismantling of abandoned buildings and in waste from primary and secondary aluminium production. Raffineria Metalli Capra recovers and recycles metallic aluminium waste, such as scrap from aluminium foundries, salt waste and aluminium screened waste; it also recovers aluminium scrap such as turnings, aluminium castings, aluminium plate and radiators coming from demolition, production waste, and selection and flotation plants.

Systems and production processes.

The production process is split into two different phases carried out by two distinct procedures with two systems:

  • Dry grinding system;
  • System for sodium chloride recovery through salt waste used in wet grinding process.

Grinding system.

The process differs according to the raw material used:

A) Aluminium scrap: size reduction with shearing system, which optimises a further size reduction with hammer mill that grinds and homogenises the material which is then stored in silos. During the manufacturing, cycle iron removal systems eliminate the iron and screening systems remove the small particles (>1mm) of inert material that are of no use for casting and refining. The finished product of the correct size is then stored in silos ready to be sent to the Castelmella plant.

B) Aluminium waste and salt waste from rotary kiln: after size reduction with hydraulic brake systems, the material is placed into the hammer mill in order to obtain a grinded product (aluminium grains) which, following iron removal and screening, is stored in silos and transferred to Castelmella plant.

C) Aluminium and salt powders obtained from screening systems are also stored for use in the sodium chloride recovery system.

All processes are controlled by suction systems that capture the powder and the fumes are then purified.

The process is divided into the following steps:

  • Salt waste grinding process to recover the trapped metal;
  • Powder dissolution within a completely closed system;
  • Vacuum filtering of the product to obtain the liquor (H2O and sodium chloride solution);
  • Liquor crystallisation to obtain sodium chloride to be used in the refining process.