aluminium Scrap Decoating (USA)


CASE STUDY 11. Aluminium Scrap Decoating US Granules (USA) 2001

HCl emissions reduced from 1000mg/Nm3 to 5mg/Nm3

Process: To recover aluminium scrap from plastic foil.

A Glosfume high temperature ceramic filter system replaced an existing bag filter that had suffered severe corrosion. This was due to being operated at low temperatures, combined with extremely high HCl levels, during aluminium scrap decoating.

Lime injection provided inadequate HCl removal and led to problems with CaCl2 'setting' in the bag filter house. The problem was eventually overcome by utilising sodium bicarbonate at high temperature in conjunction with the new Glosfume high temperature ceramic filter system.

This aluminium scrap decoating customer benefited from a more appropriate hot air filtration solution, giving greater efficiency and reliability, as well as consultancy to diagnose and rectify the CaCl2 'setting' problem - again leading to enhanced decoating plant performance.

Emissions levels after the Glosfume filter.

Element life span 6 years