Treatment of municipal solid wastes by steam classification for recycling and biomass utilization

A patented method of steam classification (the Holloway Process) and a prototype process unit have been investigated. The process treats municipal solid wastes (MSW) with steam and pressure to yield sterilized recyclable metals, glass, and plastics and a cellulosic pulp. After processing, the components of the mixture are separated into three sizes by vibratory screening. The recyclable materials must be subsequently separated from the screened fractions. Process conditions have been optimized to maximize the yield of a sterile cellulosic fraction that has a variety of possible end uses, such as compost, combustion fuel, and feedstock for conversion to fuels and chemicals.