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TITLE Development of Melting Technology for Waste Dedicated to Environment
(Joint Program to Promote Technological Development with the Private Sectors)
AUTHOR qhsd|`l`f`r`jh mnDR k`anq`snqx in Kubota Corporation

In Japan most of waste is incinerated and the incineration ash is disposed to final site, however, it has been serious problem that we are lack in land for the new site. It's said that we just have the room for only a couple of years, and the problem is increased due to plastic waste which is hard to treat with current process. In addition, the site may have pollution problem caused by hazardous. For these reasons, there are some incinerator systems in which melting furnace is installed, however, the system is complicated and required some progress in terms of energy efficiency.

To solve these problems, we have started three years research mission, qhsd|`l`f`r`jh mnDR k`anq`snqx, in charge of RITE since 1995. We think about the proposition that 'What concept of technology is essential and necessary for waste treatment?'. First, it should melt the waste to slag without any pollution and make the slag as re-usable as possible. Second, it should make the system simple and increase energy efficiency. Third, it should keep the mass of flue gas as low as possible.

To realize this concept, we utilize the combustion of combustible in waste and pure oxygen to melt remaining incombustible. We basically don't use any fuel which leads to reduce mass of CO2, thermal NOx and etc in flue gas. We apply shaft type furnace, and drying, volatilizing, burning and melting process is proceeded in a furnace simultaneously, which leads to make the system simple and increase energy efficiency. We also make it without shredder or remover for incombustible in waste. It is also possible to build the energy self-supply system by combining with steam generator, electric power generator and oxygen generator.

To realize this process, we built test-bench in 1995 and made experiments to get essential data for the process. We observed that the slag was spilt from outlet of the furnace. We also built pilot plant (scale: 4ton a day) in Dec 1996. We continue to try to ac hieve our goal that is making stable and efficient system.