The overwhelming majority of the UVBs currently collected are lead-acid, which are mainly composed of lead (64%), sulphuric acid electrolyte (28%) and plastics (8%). Lead is a material that is very easy to recycle, and can be reused an indefinite number of times.
The UVB recycling process begins with its milling in a wet medium and the subsequent separation of the electrolyte, the plastic from the casing (polypropylene) and the lead compounds. Next:
• The electrolyte is neutralized using caustic soda and subsequently sent for
treatment in a WWTP or converted into sodium sulphate, which can be used,
for example, in the manufacture of detergents or glass;
• The plastic is then processed by extrusion and used in the manufacture of,
for example, new battery casings, urban furniture, irrigation pipes or pots
• Lead compounds are fused with other materials (according to the composition
of the scrap and the specifications of the final product in production) and purified,
producing ingots or moulds. The best quality lead is used to make new batteries,
the rest being used for hunting cartridges, radiation protection barriers,
counterweights for lifts, ballasts for ships, etc.