New student-made BIS bottle recycling bin made from waste materials will be unveiled on Green Day.
Remember: Keep collecting those used batteries for the house competition on 16th April.
Why do we recycle batteries?
Batteries contain extremely toxic substances like mercury, cadmium, lithium, lead and nickel metal hydride. Battery materials pose no threat to human health when in use, but batteries discarded improperly can have dangerous health and environmental consequences because of the heavy metals the batteries contain. Batteries that end up in a landfill can leach chemicals and heavy metals into the soil, groundwater, lakes and streams. When incinerated, batteries release heavy metals into the air; these metals enter the environment in the ash created during incineration. The most recycled batteries are lead acid batteries.
Lead Acid Battery Recycling
The battery is broken apart in a hammer mill (a machine that hammers the battery into pieces). The broken battery pieces are then placed into a vat, where the lead and heavy materials fall to the bottom and the plastic floats. At this point, the polypropylene pieces are scooped away and liquids are drawn off, leaving the lead and heavy metals. Each of the materials goes into a different recycling “stream”.
Polypropylene pieces are washed, blown dry, and sent to a plastic recycler where the pieces are melted together into an almost liquid state. The molten plastic is put through an extruder that produces small plastic pellets. The pellets are sold to a manufacturer of battery cases and the process begins again.
Lead grids, lead oxide, and other lead parts are cleaned and heated within smelting furnaces. The molten melted lead is then poured into ingot moulds. After a few minutes, the impurities float to the top of the still molten lead in the ingot moulds. These impurities are scraped away and the ingots are left to cool. When the ingots are cool, they’re removed from the moulds and sent to battery manufacturers, where they’re re-melted and used in the production of new batteries.
Old battery acid can be handled in two ways: 1) The acid is neutralized and turns into water. The water is then treated, cleaned, tested in a waste water treatment plant to be sure it meets clean water standards. 2) The acid is processed and converted to sodium sulphate, a white powder that’s used in laundry detergent, glass and textile manufacturing.
Mai Van Trinh 7V