Rapid digitization in India has laid pathways for seamless operations and service delivery across the sectors of economy. It is undoubtedly solving many challenges in the 21st century for developing nations, such as India. But along with these progressive developments, the number of electronics discarded every year has risen exponentially. 70% of the E-Waste in India comes from computers; mobiles contribute 12%; and medical equipment contributes 8%. According to the Global E-Waste Monitor 2020, India on an average produces 3.2 million tonnes of E-Waste every year, and this number is only expected to increase.
The Government of India brought in E-Waste Management law in 2011. The law stipulated electronic manufacturing companies and importers to develop plans to manage E- waste. They had to set up E-waste collection centers or employ take back systems. It also mandated that companies inform the end users about the physical hazards of E-waste and educate them about how to handle discarded electronics. The rules were amended in 2016 to clarify the responsibilities of different parties involved. The concept of Extended Producer Responsibility was introduced, under which companies had to ensure that their electronic waste is sent to regulated E- Waste management companies.
There are 312 registered E-waste management companies but still nowhere near the number required to handle the 4.12 million tonnes of E-waste. The informal sector still handles most of the E-waste generated. But unlike the unorganized sector of regular waste management, E-Waste Management requires sophisticated machinery such as granulators, electrolysis systems, and is very capital intensive. The workers in this sector also need to have a specific skill set that might not be available readily.
E-Waste Management plants operate differently according to the metals they are processing, but certain standard processes are still followed.
- Sorting – It refers to segregating material on the b It is the most crucial part of the entire process. Unlike other waste recycling plants, sorting is the key to profitability in E-Waste. When a consignment arrives at the plant, it has everything from laptops, television sets, mobiles to heaters, vacuum cleaners, air conditioners etc. Primary separation is required as different equipment have different types of metals. A TV has lead in high concentration, and a stabilizer will have more copper. So primary separation reduces the effort in later stages.
- Dismantling- The majority of the equipment have plastic parts attached, so it is necessary to dismantle the equipment manually and separate the materials which cannot be recycled as e-waste. Dismantling is done manually on a macro level as it is difficult to disassociate smaller plastic parts manually. For example, when recycling a mobile phone, the glass screen is separated first, and then the chipboard is separated from the main plastic body of the phone. If there are certain plastic parts in the chipboard, they will be sent to the next stage. In this stage, physically hazardous materials such as lamps containing mercury, batteries containing lead, ink and toner cartridges are removed to ensure the safety of workers and end-users.
- Primary Shedding: The material passes through the primary shredder where it is broken down into large chunks of material. It passes through an overboard magnet at the end of the line, which separates the ferrous materials of the line. At the end of the ferrous line, workers manually discard materials that weren’t fully separated to get clean steel and ferrous material. This process is repeated 2-3 times to get more refined and distinct ferrous and non-ferrous material lines
- Secondary Shredding: In this stage, the material is further reduced in size using a heavy shredder and a hammermill. Aluminum or copper stuck to plastic will be separated in this stage.
- Drum Magnet- The material is then sent through a drum magnet, any ferrous or steel material which was not separated in the earlier stage, is separated here
- Eddy Current Separation – In this stage, an alternating current is passed over the material, which gives temporary magnetic properties to materials that conduct electricity. A magnet separates the electricity conducting materials such as aluminum and copper. Many E-Waste recyclers stop at this step and send the separated products to specialized recyclers.
- Smelting- For facilities that further recycle the material, the next major step is smelting. Materials containing copper, aluminum, silver etc are melted. This can be done either through hydrometallurgy or pyrometallurgy. The impure metal is then cooled down and deposited on rod like structures.
- Electro Refining: The impure metal after smelting, is put into an electrolytic solution with a pure metal. When an electric voltage is applied, the pure metal from the impure rod(anode) leaves it and gets deposited on the pure metal rod(cathode). This process is used to get pure copper, aluminum etc.
- Anode Mud Processing – A residue is deposited under the anode rod as the pure metal leaves the anode. This mud is further processed as it can contain other precious metals not separated in the electro refining step.