18-Env-A6 Solid Waste Engineering and Management · May 2014
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Reference texts: Tchobanoglous, Theisen & Vigil, Integrated Solid Waste Management: Engineering Principles and Management Issues; Vesilind, Worrell & Reinhart, Solid Waste Engineering; Davis & Cornwell, Introduction to Environmental Engineering (6th ed.); CCME, Guidance Document on Landfill Gas Management; Canadian Environmental Protection Act, 1999.
Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.
(1) Manual and mechanical sorting — picking lines (manual sorters removing target/contaminant items from a conveyor) and automated optical or near-infrared sorters at a materials recovery facility (MRF). (2) Size reduction and screening — shredders/grinders to reduce particle size, paired with trommel or vibrating screens to separate material by particle size. (3) Magnetic and eddy-current separation — overhead or drum magnets recover ferrous metals, while eddy-current separators recover non-ferrous metals (primarily aluminum); air classification (density-based separation of light versus heavy fractions) is a related common unit operation.
