18-Env-A6 Solid Waste Engineering and Management · December 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.
This paper prints marks IN FRONT of the question number on every line (e.g. "5 1. What are the elements…", "4 16. All 29 questions are answered in full.
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.
Effective diversion programs remove the target materials from the residual (disposed) stream, so the residual composition shifts to a higher proportion of non-recyclable, non-compostable and composite materials (e.g. multi-layer packaging, textiles, non-recyclable plastics). Because paper and food/yard waste (high moisture, lower heating value) are diverted first, the residual stream's average moisture content typically decreases and its average heating value (energy content) increases — a consideration for any downstream waste-to-energy facility. Diversion also tends to reduce total residual density (as the denser organics leave) and can shift the residual's chemical composition toward a higher plastics/synthetic fraction.
