Summary: | 碩士 === 國立屏東科技大學 === 環境工程與科學系所 === 100 === In responding to the zero-waste policy, the incineration treatment of municipal solid wastes has become an important issue; therefore, we hope to handle incineration ash wastes effectively in order to achieve zero-waste emissions. Heavy metals and other chlorinated organics are generated from the municipal solid wastes incineration process and they are part of the so called fly ashes, they are usually recognized as hazardous industrial wastes through the Toxicity Characteristic Leaching Procedure (TCLP) test. However, the present treatment of incineration fly ash by means of the solidification/stabilization process, the washing process to remove chloride prior to make cement and lightweight aggregate or to make environmental cement by the high-temperature sintering. These processes have several disadvantages of high technical level required, high initial set-up cost, operations and maintenance costs.
The goal of international trends is to efficiently improve the recycling of the ash wastes. In order to break through the incineration fly ash, unable reused, what is one of the hazardous industrial wastes. In this study, the samples collected from two large incinerators in the southern part of Taiwan included unhandled semi-dry scrubber ash, heat-saving devices ash, super-heaters ash, boiler ash, bottom ash and treatment sediment ash, we used the physical treatment to treat the incineration ash wastes, to effectively decrease the concentration of heavy metals in order to fully fit the regulation levles of TCLP standards. Furthermore, our developed method also achieves the goals of low cost and high engineering feasibility. The results showed that the particle size of ash wastes were sieved over than 0.074 mm and mixed sample together. When the mixing ratio was controlled fewer than 33%, the indicators of the extracted concentrations of Pb, Cu, Cr, Cd, Ba and Se could be effectively reduced to less than TCLP regulatory standards. Therefore, MSWI ash wastes could be considered of reuse purposes.
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