NKK to Test Shredder Dust Separation And Recycling Technology
NKK is working on the commercialization of a technology to recycle shredder dust from end-of-life cars and home electric appliances by using coal tar-based oil, a byproduct of steelworks. The research project is being promoted with a grant from the New Energy and Industrial Technology Development Organization (NEDO), with the aim of finding effective uses for waste shredder dust. NKK's work on the development of high-efficiency waste shredder dust separation and recycling technology began in 1997 at the company's Materials & Processing Research Center in Fukuyama, by installing an experimental facility. In the NKK process, which is based on heterogeneous resin separation technology, the shredder dust is heat-treated using coal tar oil as a thermal medium and separated by gravity to achieve a material recovery rate as high as 90%. At a relatively low temperature of around 300°C, shredder dust is separated completely into waste plastics and metals within 30 minutes. The waste plastics can then be used as blast furnace feed, the precipitated metals can be recovered for reuse, and the only residue is sand and glass. NKK is currently building a demonstration test plant with a processing capacity of around 200kg per hour at its Keihin Works. The test plant, scheduled to be commissioned in January 2000, will consist of a heating and insulation tank that will hold 16 tons of coal tar, a dust feeder and metal and plastic recovery systems. By March 2000, NKK plans to identify the ideal conditions for coal tar and establish the service life and cost of the system in answer to the NEDO grant. The results of the tests will be reflected in the development of a commercial scale system, capable of processing 10,000-100,000 tons a year to be used by steelmakers and shredder dust operators. |
