18-Env-B5 Industrial & Hazardous Waste Management · May 2016
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Reference texts: Nemerow & Dasgupta, Industrial and Hazardous Waste Treatment, 2nd ed.; Metcalf & Eddy, Wastewater Engineering: Treatment and Resource Recovery, 5th ed.; Davis & Cornwell, Introduction to Environmental Engineering, 6th ed.; LaGrega, Buckingham & Evans, Hazardous Waste Management, 2nd ed.; CCME, Guidelines for the Management of Biomedical Waste in Canada (1992); Canadian Environmental Protection Act (CEPA), 1999; Basel Convention on the Control of Transboundary Movements of Hazardous Wastes (1989); Canadian Nuclear Safety Commission (CNSC) regulations on radioactive waste; provincial hazardous waste regulations (e.g. BC's Environmental Management Act and Hazardous Waste Regulation).
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.
The greatest challenge is the extreme variability of industrial wastewater — in flow rate (batch operations, shift changes, seasonal production), in strength (BOD/COD/TSS concentration can swing by an order of magnitude within a single process cycle), and in composition (a different, sometimes toxic or inhibitory, constituent mix from one industry, or even one production run, to the next). This variability makes it difficult to design a single treatment train that reliably meets discharge limits at all times, unlike relatively steady, well-characterized municipal sewage; equalization, robust process control, and industry-specific pretreatment are all responses to this fundamental unpredictability.
