Waste battery recycling
There are three types of waste batteries that are commonly used in the world: solidified and buried, stored in waste mines, and recycled.
1. Solidified and buried in waste mine
For example, a factory in France extracts nickel and cadmium, and then uses nickel for steelmaking, and cadmium is reused for battery production. The rest of the waste batteries are generally shipped to specialized toxic and hazardous landfills, but this practice is not only too expensive but also wasteful because there are many useful materials that can be used as raw materials.
2. Recycle and re-use
(1) Heat treatment
There are two factories in Switzerland that specialize in the processing of used batteries. The method used by the company is to grind the old batteries and send them to the furnace for heating. At this time, the volatilized mercury can be extracted. At higher temperatures, the zinc also evaporates. The same is precious metal. After the iron and manganese are fused, they become the ferromanganese alloy required for steel making. The plant can process 2,000 tons of waste batteries a year, and can get 780 tons of ferromanganese alloy, 400 tons of zinc alloy and 3 tons of mercury. Another factory directly extracts iron from batteries and sells metal mixtures such as manganese oxide, zinc oxide, copper oxide and nickel oxide directly as metal scrap. However, the heat treatment method is costly, and Switzerland also requires a small amount of waste battery processing fee to be charged to each battery purchaser.
(2) "Wet treatment"
A “wet treatment” device is being built in the suburbs of Magdeburg. In addition to the lead storage battery, all kinds of batteries are dissolved in sulfuric acid, and then various metals are extracted from the solution by means of ionic resin. The heat treatment method is pure, so it is sold at a higher price in the market, and 95% of the various substances contained in the battery can be extracted. Wet processing eliminates the sorting process (because sorting is done manually, it adds cost). Magdeburg's annual processing capacity can reach 7,500 tons, although its cost is slightly higher than the landfill method, but the precious raw materials will not be discarded and will not pollute the environment.
(3) Vacuum heat treatment
The vacuum heat treatment method developed by Alte Company of Germany is cheaper, but this first needs to sort out the nickel-cadmium battery in the waste battery. The waste battery is heated in vacuum, and the mercury is quickly evaporated, then it can be recovered, and then the remaining raw materials are used. Grinding, extracting metallic iron with a magnet, and extracting nickel and manganese from the remaining powder. The cost of processing one ton of used batteries is less than 1,500 marks.