How to improve waste nickel metal hydride battery recycling technology?

Source: 2020 - 04 - 06 12:08 hits: time spent nickel metal hydride battery recycling process improvement nimh batteries with high energy density, big output power, fast charge and discharge and harmful to the environment without heavy metals, and low cost, are widely used in automotive power industry in recent years. However, with the wide use of nimh batteries, also produced a lot of waste. According to statistics, 2005 nimh battery scrap amount has reached 1 billion. These abandoned nimh batteries contain 7500 tons of 1000 tons of nickel, cobalt and 2500 tons of light rare earth elements, these elements into the environment, to a certain extent caused the pollution of the environment. Nimh batteries, on the other hand, the nickel, cobalt and rare earth elements is of valuable metallic elements, low grade, wide application and high value. Therefore, used nimh batteries is the precious resources processing dislocation cells. Among them, the rare earth elements in the nimh batteries are widely used in electronics, petrochemical, metallurgical and other industries. Mining rare earth resources, rare earth resource is more and more nervous, and a large number of rare earth elements contained in the waste nickel metal hydride batteries, so waste nickel metal hydride battery recycling of rare earth elements can not only reduce pollution, also can relieve the pressure on resources, increasingly nervous. Nickel metal hydride battery cathode hydrogen storage material is mainly mixed rare earth series of hydrogen storage alloys. Rare earth elements in the nimh batteries mainly for light rare earth elements, including La and Ce relatively large. At present, the nickel metal hydride battery recycling method are mainly coking processing technology and the technology of wet processing. Coking and purification technology used in coking process. Because the technology can't effectively from the ash in the recovery of rare earth elements, and there are high energy consumption, long cycle, high requirements for equipment, processing process to produce the problem such as harmful gases, is limited in practical application. Hydrometallurgy process because of its maturity, low requirements for equipment, low cost and less environmental pollution has been widely used. The universal methods of dealing with the nimh batteries have a mechanical method, the method and wet method, biological metallurgy method, is the cathode separation technology and nimh batteries renewable technology. Among them is given priority to with wet processing. The main factors influencing the waste nickel metal hydride batteries wet processing with acid, acid concentration, leaching temperature, leaching time, liquid-solid ratio, stirring intensity, etc. Researchers usually by orthogonal test to determine the best treatment process under the influence of these factors. Based on current research reports, waste processing of nimh batteries has achieved fruitful results, but most of these processing method still stays in the laboratory research stage, there are very few large-scale applications, a lot of processing method has inherent defects. A hydrometallurgical studies the terms of the dissolution of spent nickel metal hydride batteries, and the recycling of rare earths conditions were studied. The method has low pollution, high speed, and the advantages of method is simple, is expected to be further applied in industrial production.