Although the waste battery is small, it is harmful. However, the pollution of waste batteries has not received due attention, because it can not be felt through the senses like garbage, air and water pollution, and it has great concealment. At present, China has become a big country in battery production and consumption, and the pollution of waste batteries is a major environmental problem that needs to be solved urgently. In terms of volume and weight, waste batteries are insignificant in domestic garbage, but their harm is very great. Batteries contain heavy metals such as mercury, cadmium and lead. Mercury is very toxic, and lead can cause nervous disorder and nephritis. Cadmium mainly causes kidney injury and bone diseases-osteoporosis, rickets and fractures. If waste batteries are mixed with domestic garbage and buried, heavy metals seeping out over time may pollute groundwater and soil.
For a long time, when producing dry batteries in China, a toxic substance-mercury or mercury compounds has to be added. In China, the mercury content of alkaline dry batteries is 1 ~ 5%, and that of neutral dry batteries is 0.025%. Every year, the mercury used in the production of dry batteries in China reaches dozens of tons. Mercury is commonly known as "mercury". Mercury and its compounds are toxic. Scientists have found that mercury has obvious neurotoxicity and has adverse effects on endocrine system and immune system. Minamata disease is a public hazard that shocked the world in Japan in 1950s, which was caused by mercury pollution.
More than 40 years ago, in Minamata, a seaside town in southern Kyushu, Japan, a strange disease appeared among local residents. The patient began to lisp, gait instability, quadriplegia, and finally the whole body spasms, mental disorders, and died in painful torture. Later, more and more people were infected with the disease, and even cats and seabirds showed the same symptoms. Later, medical workers found toxic methylmercury from the dead and the bodies of marine fish, which proved that people were poisoned by eating contaminated fish. After investigation, it turned out that the local Japanese nitrogen fertilizer industry company discharged mercury-containing wastewater into Minamata Bay all the year round, which polluted the seawater with mercury, and the seafood caught locally contained high concentration of methylmercury.
In order to restore the ecological environment of Minamata Bay, the Japanese government spent 14 years and invested 48.5 billion yen to excavate 4 meters of mercury-containing sediments in Minamata Bay and completely remove them. At the same time, an isolation net was set at the entrance of Minamata Bay to catch all the polluted fish in the bay for landfill. Masayoshi Yoshii, the mayor of Minamata, Japan, who witnessed the outbreak of Minamata disease, said with emotion: "After nearly half a century of unremitting efforts, we finally got out of the shadow of Minamata disease and are building a new Minamata city. I hope that the whole world will learn from the lessons of Minamata disease in Japan, get rid of ignorant production methods and advocate civilized production methods. "
It can be seen that the harm of waste batteries to the environment and human body is far beyond our imagination. Discarding batteries at will not only pollutes the environment, harms human health, but also wastes resources. Based on the annual output of 654.38+000 billion batteries, the annual consumption will be 654.38+0.56 million tons of zinc, 226,000 tons of manganese dioxide, 2,080 tons of copper, 27,000 tons of zinc chloride, 79,000 tons of ammonium chloride and 43,000 tons of carbon rods. Therefore, it is imperative to recycle waste batteries to benefit the country and the people. This requires people to find ways to solve the pollution problem of waste batteries.
Disposal of waste batteries
The recovery of waste batteries is the first step of recovery, and reprocessing is the key to recovery. At present, the recycled waste batteries are still lying in the warehouse and homeless.
The technology of disposing of waste batteries is not a problem. Developed countries already have ready-made technology, so just use it. It is understood that a "wet treatment" device is being built in the suburb of magdeburg, Germany, in which all kinds of batteries except lead batteries are dissolved in sulfuric acid, and then various metals are extracted from the solution with the help of ionic resin. The raw materials obtained in this way are purer than the heat treatment method, so the price is higher in the market, and 95% of the substances contained in the battery can be extracted. Wet processing can save the sorting process (because sorting is manual operation, which will increase the cost). The annual processing capacity of this device in magdeburg can reach 7,500 tons. Although its cost is slightly higher than that of landfill, precious raw materials will not be discarded and will not pollute the environment. The annual processing capacity of the device can reach 7500 tons.
The vacuum heat treatment method developed by Alte company in Germany is cheaper, but it needs to sort out the nickel-cadmium batteries from the waste batteries, heat the waste batteries in vacuum, quickly recover mercury, then grind the remaining raw materials, extract metallic iron with magnets, and then extract nickel and manganese from the remaining powder. The cost of treating one ton of waste batteries is less than 1500 mark.
Switzerland: There are two factories specializing in the processing and utilization of waste batteries. The method adopted by Butrick Company is to grind the waste batteries and send them to the furnace for heating. At this time, the volatilized mercury can be extracted, and zinc will also volatilize at a higher temperature. It is also a precious metal. Iron and manganese are melted to form ferromanganese alloy for steelmaking. The factory can process 2000 tons of waste batteries a year, and can obtain 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 as metal scrap. However, the heat treatment method is expensive, and Switzerland also stipulates that each battery buyer should be charged a small amount of special expenses for waste battery treatment.
As far as we know, some domestic scientific research units and enterprises have also developed related technologies. The Donghua Xinxin Waste Battery Recycling Factory in Hebei Province, which adopts the technology of University of Science and Technology Beijing, is under construction. The Beijing Municipal Development Planning Commission also approved the adoption of European technology and equipment to establish a waste dry battery treatment plant. Henan Xinxiang Battery Factory has technicians who have designed a set of technology and production equipment for recycling used batteries. After two years of tackling key problems, Anshan City, Liaoning Province has successfully developed a harmless treatment process for recycling used batteries, which has been demonstrated by relevant experts and departments.