On completion of this subject the student should be able to:
1. Discuss fully the different types of water and its quality, sources of water and their likely contaminants, different process in water treatment and design simple water supply system;
2. Discuss fully the different sources of wastes entering the water system, how waste water is treated to safe level before discarding into the environment, ultimate waste disposal and transformation of waste into useful bio products.
3. Apply the principles of cleaning and sanitation and their applications in the food industry;
4. Carry out water quality tests such as BOD, COD, water hardness, turbidity, alkalinity, trace metals, etc. and microbial quality of water and waste water.
Water treatment: identify the sources of water, define water quality, describe the water treatment process – discussing screening, coagulation and flocculation process, filtration, removal metals and water softening process, chlorination – chlorine break points and concentration of chlorine and removal of dissolved gasses, colours and foreign matter; The principle of water hardness and how to soften water. There is a project component to design a simple water supply system for village or factory usage; Cleaning and sanitation: the mechanism of cleaning and sanitation as it applies to different food systems, cleaning practices in food and allied industries; Waste treatment: identify sources of contaminants entering the water system, factory waste treatment and discuss different levels of BOD associated wastes leaving the factory floor, Steps in the waste treatment process: (a) primary waste treatment – screening, flocculation and coagulation, filtration and sedimentation and chlorination/disinfection (b) secondary waste treatment – subjecting the waste to aerobic and anaerobic treatments in lagoons, ponds and digester; Waste product utilization in particular, methane production as clean energy source; Ultimate waste disposal: merits and disadvantage of disposal means such as composting, incineration and landfills and how safe the liquid is putted back into the environment; Quality testing covers both theory and practical aspects – major test areas to concentrate on pH, temperature, water hardness, alkalinity, heavy metal contaminants, COD, BOD, turbidity and others.
De, A. K., Environmental chemistry, New Age International, New Delhi, India, 2010.
Brennan, J. G., Butters, J. R., Cowell, N. D., Lilly, A. E. V., Food engineering operations, Elsevier Applied Science, London, UK, 1990.
Kiely, G., Environmental engineering, McGraw-Hill, London, UK, 1997.
International standards for drinking water, WHO, Geneva, Switzerland, 1971.
Operation of waste water treatment plants, Water Pollution Control Federation, Washington, USA, 1976.
Continuous assessment 40%
Written examination 60% (1×3 hrs.)
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