perhaps the most important nutrient in our diets. In fact, a human adult needs
to drink approximately 2 liters (8 glasses) of water every day to replenish the
water that is lost from the body through the skin, respiratory tract, and urine.
But some water sources cannot safely be used to meet our requirement for
drinking water. In fact, 99.7% of the Earth's water supply is not usable by
humans. This unusable water includes saltwater, ice, and water vapor in the atmosphere. Only freshwater,
which is contained in rivers, lakes, and underground sources, can be used for
human consumption. Furthermore, many freshwater sources are not suitable for
humans to drink. Many serious diseases, such as cholera, are caused by drinking
water that contains parasitic microorganisms.
Water containing large amounts of industrial waste or agricultural chemicals (e.g.,
pesticides) can also be toxic and unfit for drinking. Hence, humans have a
great need for a reliable source of clean freshwater for drinking.
Water treatment is a process
of making water suitable for its application or returning its natural state.
Thus, water treatment required before and after its application. The required
treatment depends on the application. For example, treatment of grey water (from bath, dish
and wash water) differs from the black water (from flush toilets). Composting
toilet is not allowed in urban
dwelling. Yet, composting toilets are used in a 30,000-square-foot office
complex at the Institute of Asian Research, University of British Columbia.
treatment involves science, engineering, business, and art. The treatment may
include mechanical, physical, biological, and chemical methods. As with any
technology, science is the foundation, and engineering makes sure that the
technology works as designed. The appearance and application of water is an
- Chemical education and treatment
- Water treatment chemicals
- Industrial water treatment