Control of Glass in Waste‐to‐Energy Production

Mechanisms that contribute to glass contamination of waste‐to‐energy products from air classifiers are studied, and modifications to unit processes are suggested. Vertical air classifiers are used to extract the combustible organic fraction from municipal solid waste (MSW); however, unit operations preceding these classifiers tend to produce glass particles which, despite a relatively high density, tend to move with the organics once they reach the classifier. Experience in burning waste‐to‐energy fuel indicates critical problems are associated with the presence of these inorganic fines in the fuel, including excessive slagging on incinerator walls and abrasion of mechanical parts. This research investigates the relationships between glass particle size and air velocity within the classifier, and details the effects paper particles and moisture have on glass particle transport. Laboratory results lead to conclusions which suggest changes in the operation of air classifiers, and imply designs for selected unit operations which precede the classifiers.