Report on the generation and recycling of nickel cadmium battery
- Production and scrapping of nickel cadmium battery
- Status of nickel cadmium battery recycling
- Countries that mainly recycle nickel cadmium battery
Nickel cadmium battery refers to an alkaline battery that uses metal cadmium as the negative electrode active material and nickel hydroxide as the positive electrode active material. The positive and negative electrode materials are respectively filled in the perforated nickel-plated steel strip (or nickel strip), and the plates are made by pulping, rolling, sintering, forming or pasting, drying, and pressing, etc.
The material such as woven cloth is used as the isolation layer, the potassium hydroxide aqueous solution is used as the electrolyte solution, and the electrodes are assembled in a plastic or nickel-plated steel shell by winding or stacking.
Large pocket and open nickel cadmium battery are mainly used for starting or emergency power supply for railway locomotives, mines, armored vehicles, aircraft engines, etc. Cylindrical sealed nickel cadmium battery are mainly used in portable appliances such as power tools and shavers. Besides, lithium battery is also used for power tools and there are some famous factories. You can read our top 10 lithium battery factory for power tools article to get more information.
Small button nickel cadmium battery are mainly used for cordless phones and electric toys with low current and low rate discharge. Due to the pollution of waste nickel cadmium battery to the environment, they are gradually being replaced by metal hydride nickel batteries or lithium-ion batteries with better performance.
Recycling of used batteries refers to the recycling and reuse of used batteries. Waste nickel cadmium battery are hazardous waste, and their recycling is included in the management scope of China’s hazardous waste recycling certificate.
Production and scrapping of nickel cadmium battery
Production of NiCd Batteries
In 2013, the output of nickel cadmium battery in China was about 161 million pieces. The EU battery directive clearly restricts the use of nickel cadmium battery for civilian products, and the output of nickel cadmium battery is declining year by year. In 2018, the output of nickel cadmium battery was about 83.6957 million pieces, and the export volume was 58.587 million pieces, a year-on-year decrease of 24.13%.
The import volume was 8.4252 million pieces, a year-on-year decrease of 1.18%; China’s supporting and consumption volume was 33.534 million pieces, a year-on-year decrease of 19.43%.
In 2015, China’s total cadmium output was 8,162 tons, of which the production of 110 million nickel cadmium battery consumed about 4,009 tons of cadmium, accounting for 49.12% of the country’s total cadmium use; in 2016, China’s nickel cadmium battery used about 4,000 tons of cadmium, accounting for It accounts for 49% of the total use of cadmium in the country; in 2018, China produced about 83.7 million nickel cadmium battery, consuming about 3,050 tons of cadmium.
Number of nickel cadmium battery enterprises
At present, there are about 120 manufacturers of nickel cadmium battery and nickel-hydrogen batteries, and more than 60 enterprises engaged in the recycling of waste nickel cadmium battery.
Nickel-cadmium battery enterprises are mainly concentrated in Guangdong, Jiangsu, Tianjin and other regions. Usually, companies that produce nickel cadmium battery also produce nickel-hydrogen batteries, and their market channels, production process equipment, and material configuration are basically similar. The main manufacturers of nickel cadmium battery include BYD, etc. The production of nickel cadmium battery in Guangdong Province accounts for about 40% to 50% of China’s total production.
The amount of waste nickel cadmium battery
In 2014, the production of waste nickel cadmium battery was about 300 million; in 2017, the production of waste nickel cadmium battery was about 240 million. In 2018, about 62 million used nickel cadmium battery were produced. showing a downward trend year by year.
Status of nickel cadmium battery recycling
At present, the recycling and processing technologies of waste nickel cadmium battery are mainly divided into two categories: wet method and pyrotechnical method, among which pyrotechnical processing includes vacuum processing technology and conventional pyrometallurgical processing technology.
Different methods have their own advantages and disadvantages: hydrometallurgy has disadvantages such as low purity of recovered products, low recovery rate and high cost, and the treatment process is long, and a large amount of discharged sewage may cause secondary pollution to the environment.
Although pyrometallurgy has no concerns about waste water, if the waste gas and waste residue are not effectively treated, it will still lead to secondary pollution. Vacuum metallurgy has the least impact on the environment, but the equipment investment is relatively large, which is a better choice in the long run.
- Wet recycling
The principle of hydrometallurgy is based on the fact that metals and compounds in waste nickel cadmium battery can be dissolved in acid, alkaline solution or some kind of solvent, and then they can be removed by selective leaching, chemical precipitation, electrolysis, solvent extraction, replacement and other means. Valuable metals are recovered, thereby reducing the pollution of waste nickel cadmium battery to the environment.
- Fire recovery
The nickel-cadmium battery is broken, and the volatile nature of metal cadmium is used to recover cadmium by distillation in the presence of a reducing agent, and then recover nickel or form Ni-Fe alloy with nickel and iron. The pyrotechnic process is simple, the purity of recovered cadmium is high, and it is easier to realize industrialization, but the energy consumption is large and the effective recovery of nickel is often neglected.
Countries that mainly recycle nickel cadmium battery
At present, there are mature waste nickel-cadmium battery treatment technologies. China is also active in research on waste nickel-cadmium battery treatment and recycling technologies, but most of them remain in the laboratory stage. With the gradual elimination of nickel cadmium battery, China currently specializes in recycling nickel There are very few cadmium battery companies.
Denmark is the first country in Europe to recycle batteries. In 1997, the recycling rate of nickel cadmium battery has reached 95%. The United Kingdom began to recycle batteries in 1998. The main types of recycling are nickel-cadmium and nickel-metal hydride lithium batteries. In 1999, about 450 tons of waste batteries were recycled.
France has been recycling waste batteries since 1999, and has several large-scale battery recycling enterprises, mainly using the method of first decomposition and classification, and then pyrometallurgy to recycle and treat waste nickel cadmium battery.
Japan has always been at the forefront of the world in the treatment and recycling of waste batteries. The recovery rate of secondary batteries such as nickel cadmium battery has reached 84%. Generally, the method of first dissection and roasting, and then separation is used to recover useful metals or their compounds.
At present, China’s management system for waste batteries is still in the process of standardizing and forming, especially for the lack of management rules for the recycling of waste nickel cadmium battery. At the industrial level, there is a lack of specialized waste nickel-cadmium battery recycling and processing enterprises. Most of the enterprises mainly focus on the recycling of resources of various types of batteries, and have not yet formed large-scale and industrialization.
Although in the long run, most of the nickel cadmium battery will be replaced by more environmentally friendly nickel-hydrogen batteries, lithium-ion batteries, etc., and gradually withdraw from the market, there are still some application fields that have a certain demand for nickel cadmium battery.
Therefore, in order to reduce the environmental risks that may exist in the collection, transportation, storage, and disposal of waste nickel cadmium battery, the recycling and reuse of nickel cadmium battery should be taken as an important part of the construction of China’s waste battery management system. Refine and improve the relevant recycling technology management norms and standard systems, carry out recycling pilot work, study recycling technology and equipment, and explore the formation of a recycling industry model.