New Municipal Solid Waste Fluidized Bed Incinerator - The Development Of Tubular Fluidized Bed

With the rapid development of economy, the disposal of municipal solid waste (MSW) has drawn great attention all over the world. The conventional method for disposing MSW couldn't meet with the new demands of the society. MSW combustion technology, one of the MSW disposing technologies, has been paid much attention to because it can make MSW volume reduction, energy recovery and harmless. New kind of incinerators should be designed according the situations in our country. The technology of MSW incineration is on the elementary stage, and little work has been done in this field. So it is necessary to research and develop a new MSW incinerating technology that can deal with Chinese MSW well. According to the background of simplifying the pretreatment equipment, as well as incinerate Chinese MSW well, the purpose of this paper is to research a new style of distributor that can be used in the MSW incinerator.The pipe air distributor is a new style distributor in the fluidized bed incinerator. It combines merits of the fluidized bed and the moving bed. It can meet the needs of cooling the clinkers quickly and removing big clinkers smoothly. This device successfully solves the conflict between clinker cooling and the feeding of the bed materials. This equipment has a lot of advantages, such as simple structure, low costs, low-pressure loss, smooth discharge, convenient maintenance, and so on. Two test facilities of pipe air distributor have been built up. In this paper the characteristics of fluidization of the new system have been studied. The hydrodynamic and mixing in the cool tester are also studied. The result of experimentation indicates that the pipe air distributors have different fluidization and lower distributor pressure drop than the conventional distributor incinerator with better mixing property. When combustors are running, the fluidized zone and moving zone distribute in the bed in turns; the pipe distributor fluidized bed combustor have the similar minimum fluidized velocity to the conventional fluidized bed combustor with slightly higher pressure drop, otherwise, the pressure drop without particle is lower than the conventional fluidized bed. The mixture in the pipe distributed fluidized bed is independent with the physical characters of the bed materials, such as density volume. Materials can get uniformity mixture with the enough fluidized velocity and enough time. The result of discharge test proves that pipe distributor fluidized bed incinerator can remove clinker and incombustible things in time under successive function. At the same time it can assure the material balance in the incinerator and cool the bed. But the pipe air distributor has a disadvantage of asymmetrical distributing gas in the direction of axis. This paper put forward three solutions to this problem. Thus it can be seen that pipe distributor incinerator is the ideal MSW incinerator in our country. This paper establishes the theoretical foundation for the design and application of pipe air distributor MSW incinerator.