Batteries and accumulators placed in red and black collection boxes are taken from the store to the Akkuser Oy processing plant in Nivala. Akkuser is a logistics centre of sorts: it sorts different batteries and accumulators into different fractions. This is important, as each type of battery and accumulator requires a different kind of processing procedure in order for the materials contained in them to be recycled into new raw materials as thoroughly as possible. In total, more than 50% of the raw materials contained in batteries and accumulators can be reutilised as industrial raw materials.
The majority of batteries on the Akkuser processing line are alkaline batteries – they comprise approximately 80% of all batteries and accumulators recycled in Finland. First, the line workers separate other battery types from the alkaline batteries. Recognising the different battery types requires experience and a good eye, as they can sometimes look confusingly similar.
When other fractions have been separated from alkaline batteries, the line conveys the alkaline batteries to a crusher. Magnetic iron (less than 25%) is the first material separated from the crushed alkaline batteries. In Finland, the iron is refined into raw materials for construction equipment, cars, tools, etc. The remaining so-called black mass is currently delivered to a zinc smelter, where the zinc (approx. 25%) contained in the mass can be recycled to be used by the construction, automobile or pharmaceutical industry, among others.
The Finnish company Tracegrow Oy is the only company in the world to have developed technology for manufacturing ecological agricultural nutrient products from trace elements in the black mass, zinc and manganese (more than 75%). The company has successfully implemented the technology it has developed and sales of the ZM-Grow product have started worldwide.
Tracegrow is already able to recycle some of the black mass collected from recycled batteries by Paristokierrätys. In the future, it is possible that the company will convert all the black mass it receives from recycling into fertilizer.
Lithium primary batteries are carefully separated from alkaline batteries. It is imperative that their terminals have been taped over, as they may cause a fire if they short-circuit. This is why Akkuser stores them outside under a separate shelter.
From there, the batteries are delivered to Riihimäki to undergo a high-heat treatment process by Fortum. The process is designed for hazardous waste, and the flue gases generated from processing the waste are carefully processed as well. The process is less harmful to the environment than incinerating the waste with normal mixed waste.
Lithium-ion batteries that contain cobalt, i.e. primarily mobile phone and laptop batteries, are processed at the Akkuser recycling plant in a two-stage crushing process that enables safe handling of the ignition-prone and volatile Litties.
The fractions resulting from the process contain significant amounts of ingredients such as cobalt (25–30% concentrate) and copper (15–20% concentrate) that are reutilised as industrial raw materials. Cobalt is an important raw material for batteries while copper is needed in the electronics industry, among others.
The cobalt is delivered to Kokkola to the world’s largest cobalt refinery, where recycled cobalt is refined to be reutilised by the industry. Not only does recycling cobalt save energy, it also saves pristine cobalt, which is mined primarily in the Congo area under primitive conditions.
Low-cobalt or cobalt-free Lithium-ion batteries used in tools, for example, contain materials such as copper, nickel, manganese, aluminium and iron, depending on the battery type. These batteries currently comprise only a relatively small portion of all recycled batteries and accumulators, but their amount is expected to increase significantly in the near future. Akkuser is currently developing a dedicated process for batteries of this type in order to recover the materials contained in them for reutilisation as efficiently as possible.
Nickel-metal hydride batteries and accumulators, such as rechargeable small batteries that resemble alkaline batteries, are processed after sorting at the Akkuser plant. Akkuser has developed a proprietary Dry-Technology method in which the batteries are crushed and different ingredients can be separated magnetically and with other mechanical means.
The most important metals recovered from nickel-metal hydride batteries are nickel and cobalt (approx. 35% in total). Nickel is used for applications such as manufacturing stainless steel, whereas the rare cobalt is used for manufacturing batteries for various devices, especially smartphones.
Akkuser’s processing line mechanically separates button cell batteries from other batteries and divides them into large and small batteries. The small batteries are often so-called silver oxide batteries by chemical composition, containing 2–4% silver. They are delivered from the Akkuser plant to a precious metal refinery for recovery, and the silver can be reutilised by the electronics industry, among others.
Box-shaped, sealed lead gel batteries contain 65–90% lead, which is extremely harmful to the environment but easy to recycle. From the Akkuser processing plant in Nivala, lead gel batteries are delivered through a Finnish collector to foreign lead battery recycling plants for processing, where the lead is recovered and used primarily for manufacturing new lead-acid batteries. The process also involves neutralising the acids contained in the batteries.
Nickel-cadmium batteries used in devices such as old cordless tools are delivered from Nivala to suitable recycling plants, where the materials contained in them are separated in a multi-stage process.
The ferro-nickel (60%) contained in nickel-cadmium batteries is reutilised in the manufacturing of steel and the cadmium (15%) is used for applications such as the manufacturing of new batteries. Using recycled nickel saves up to 75% of energy when compared to mining pristine material.