What happens to the old batteries?
Lead Acid batteries such as those used in automobiles and golf carts have a long history of being one of the most environmentally friendly resources on the free market and are actually “greener” then soft drink cans, beer cans, newspapers, glass bottles, and tires. Indeed lead-acid batteries are an environmental success story of our time.
More than 97 percent of all battery lead is recycled. This is almost twice as much as aluminum soft drink and beer cans, newspapers, glass bottles and tires. In fact lead-acid batteries are the most recycled consumer product of our time. How are lead acid batteries recycled and reused in brand new batteries? What is the recycling process of lead acid batteries? Let’s find out.
Lead acid batteries are transported via trucks to recycling centers. Once at recycling centers batteries are broken apart in a hammermill, which is a machine that hammers the battery into pieces. Once broken the batteries components are separated into 3 categories:
Broken pieces of polypropylene plastic are collected, washed, blown dry and sent to a plastic recycler. At the plastic recycler the broken pieces of polypropylene are melted at the plastics correct melting point which is the temperature at which a polymer changes from hard and brittle to soft and pliable. Then the molten plastic is passed through a machine called an extruder that shapes the molten plastic into pellets which are then sold back to battery manufacturers to begin the new battery’s manufacturing process.
The lead acid batteries lead grids, lead oxide and other lead parts are cleaned and then heated to 621.5 degrees Fahrenheit – lead’s melting point. After the lead reaches its melting point, the molten lead is poured into ingot molds. The lead’s impurities, known as dross, float to the top and subsequently scraped away and then the ingots sit there until they are cooled. After cooling the ingots are sold back to manufacturers for use in new lead plate production.
Electrolyte – Sulfuric Acid
Spent battery acid can be neutralized using an industrial grade baking soda compound. After neutralization the acid turns into water, treated, cleaned to meet clean water standards, and then released into the public sewer system. Or another option would be to convert spent battery acid into sodium sulfate, which is used in laundry detergent, glass and textile manufacturing. Considering that a typical battery recycling plant recovers 10,000 tons of lead, about 4000 tons of sulphuric acid, and can produce about 6000 tons of sodium sulphate – there is definitely some merit into this conversion process.