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.
Physical: gravity separation/decanting, filtration, and dissolved air flotation to separate immiscible or suspended phases. Chemical: neutralization (pH adjustment), precipitation (of dissolved metals as hydroxides or sulfides), and chemical oxidation/reduction (e.g. hexavalent-to-trivalent chromium reduction, cyanide oxidation) to destroy or immobilize a hazardous constituent. Thermal: high-temperature incineration to destroy organic hazardous constituents. Stabilization/solidification: encapsulation in a cementitious or pozzolanic matrix to immobilize contaminants before land disposal. Biological: engineered bioremediation or biological treatment for degradable organic hazardous constituents at lower concentrations. Ultimate disposal: secure engineered landfilling or deep-well injection for residuals that cannot be recycled, destroyed or otherwise reduced to a non-hazardous state.
