18-Env-B5 Industrial & Hazardous Waste Management · May 2013
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 Nuclear Safety Commission (CNSC) regulatory framework and NWMO Adaptive Phased Management; Canadian Environmental Protection Act (CEPA), 1999.
All nineteen questions are compulsory on this paper and are answered in full below.
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.
Three basic factors govern the selection of an industrial wastewater treatment process. First, the influent characteristics and the required effluent quality: the process (or train of processes) must be matched to the actual flow, strength, variability and any toxic/inhibitory constituents of the specific wastewater, and sized to reliably achieve whatever discharge standard applies (a municipal sewer-use bylaw, a direct-discharge permit, or a receiving-water objective). Second, cost and resources: capital cost, operating and maintenance cost, available land area, energy demand, and the availability of trained operating staff all constrain which otherwise-technically-suitable process is actually practical for the facility. Third, reliability, flexibility and compatibility: the process must reliably handle the production-driven variability in flow and load typical of an industrial (rather than steady municipal) source, must be able to be modified or expanded as production changes, and must produce a residual (sludge, concentrate, spent media) that can itself be legally and economically managed — a process that solves the liquid-stream problem while creating an unmanageable solid-waste problem is not a real solution.
