Recent developments in electrometalurgical tankhouse environmental control

CIM Bulletin, Vol. 87, No. 981, 1994

J.A. Davis, DESOM Engineered Systems Limited King City, Ontario, and W.R. Hopkins, Minproc Engineers Inc., Englewood, Colorado

This paper presents a discussion of the mechanisms by which aerosols of the process electrolyte are entrained into the breathing environment ofcopper, zinc and nickel eIectrowinning tankhouses. Literature outlining the health effects associated with worker exposure to the acidic and metallic contaminants found in the airbome aerosols is summarized and compared with existing North American regulations. A briefreview ofthe existing technologies for the source reduction Of these aerosols is presented. This paper outlines the industry experience with use of covers, balls, beads, shapes, fixtures and chemical surfaetants. Each of these devices is ranked according to ts effectiveness in the process in which it is used, and rated according to its operator acceptance. The various forms of existing in-plant ventilation systems are reviewed with a discussion oftheir relative merits and effectiveness. Actual experience is related, detailing the methods of testing for ambient contaminant levels in a variety oftankhouse environments. duideJines are providedfor the site and process specific criteria which govem the selection and ultimate effectiveness of a particular form of ventilation system. Finally, actual project experience is cited in which hydraulic modelling is used ~ a design tool in tankhouse ventilation design. These projects include the upgrading ofexisting traditional ventilation designs, and the 'grass roots" design of a more efflcient aerosol source control system to be used in high altitude, cold weather sites.
Keywords: Metallurgy, Electrometallurgy, Environmental controls, Health and safety, Ventilation systems, Tankhouses.