An Investigation of the Effects of Density,Size and Shape Upon the Air Classification of Municipal Type Solid Waste.

摘要

The objective of this research was to determine the feasibility of separating municipal solid waste type materials into more than two fractions by passing the material through a vertical air classifier. This feasibility was demonstrated by suspending specimens of varying densities, sizes, and shapes in a vertical air classifier and noting the terminal velocities of the materials. Since most shredded solid waste approximates flat plates of varying sizes and shapes, flat plates of six different materials in aspect ratios (length over width) from one to four and in four different sizes from 0.0625 to 1.000 square inches (0.4032 to 6.4516 square centimeters) were evaluated to determine terminal velocity. The materials studied included steel, aluminum, balsa wood, cardboard, paper, cloth, and glass. The theoretical development, the experimental results, and the analysis of variance statistical tests indicate that municipal solid waste type material does exhibit a difference in terminal velocity as a function mostly of density and only slightly of the size and shape parameters tested. This indicates that municipal solid waste may be separable into several fractions provided the proper air classification equipment is used. (Author)