Study on composition and particle characteristics of shredded municipal waste for the improvement of separation efficiency in a municipal bulky waste processing facility

Abstract

In order to propose a new and more efficient method of separation for shredded municipal bulky waste (SBW), particle characteristics (namely shape, density and terminal settling velocity) were investigated. It was found that particles of the combustibles such as wood, paper and plastics were included in the fraction smaller than 50 mm. Consequently, separation of SBW into combustibles and non-combustibles by particle size is difficult. Since the particles of the various materials are of all shapes, it is difficult to sort them by shape discrimination. The overall separation efficiencies using air flow and density for SBW separation were estimated and the maximum values are as high as approximately 90% and 99% respectively. However, because of the overlapping ranges of the terminal settling velocities in air for glass, metals, rubber, and plastics, the overall efficiency will become smaller if those materials are major components of the feed. It is concluded that density separation is more suitable for the separation of combustibles and non-combustibles in SBW than air separation.

Keywords

Municipal bulky waste density terminal settling velocity combustible fraction non-combustible fraction wmr 614-4

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References

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