Water and Water Quality
Water…. What a wonder! People use it in so many ways, it is perhaps unrealistic to expect it to meet all the demands they make of it, water can and does meet all its obligations.Public health authorities, industrial firms, commercial firms, hospitals and institutions, farmers and homemakers…. each has special requirements in terms of water quality. And when water quality fails to meet these requirements, trouble begins.
Even the space age scientist gets into act when calls for deionized water t to clean the metal skins of his satellites. His request for the deionized water streams from the fact that it prevents local “hot spot” corrosion and those unwanted residue weight as his ships soar out into space. More mundane uses are for final rinsing of automobiles trucks and Aircraft
To provide the water for any demand, whether it be that of the public health authority the home maker or the space age scientist, two all-important factors must be considered: - Precisely what does analysis of the raw water supply indicate?
- To what end use will the water be put?
Analysis of water may show that it contains: - Dissolved minerals
- Dissolved gases
- Turbidity and sediment
- Colour and organic matter
- Taste and odor, and/or
- Micro -organisms.
Whether or not any of these impurities are harmful in a given situation in turn depends on:
The Nature and the amount of impurities: - The tolerance permissible for each of these impurities: and
- The end use of water.
Water of a quality that may prove unacceptable or unsatisfactory for certain requirements may be quite satisfactory in other instances. To cite an example. Water with 15grains per gallon of hardness (257 mg/liter) is objectionable for laundering and bathing. This same water however, is satisfactory for sprinkling the land
What is pure water? Can it really exist?Pure ordinary water (H20) consists of hydrogen (11.1888) percent by weight and oxygen (88.812%)
It has a slightly blue Colour and is very slightly compressible. At its maximum density at 39.2 F or 4 C, it is the standard for the specific gravities of solids and liquids. Its specific heat is the basis for the calorie and the B.T.U units of heat. It freezes at 32 F or zero degree C. Note the term “Pure water “in this definition. Though we take a great deal about “Pure water” .The phrase is more of a designation than an actuality.
Actually,”pure water” (H20) accures so rearly, that for all intents and purposes, it is a non-existent liquid. Even the term pure water is somewhat ambiguous .It has different connotations to individuals in various fields
The bacteriologist, for example, is apt to regard “pure water” as sterile liquid, that is, one with no loving bacteria in it. The chemist, on the other hand, might well classify water as pure when it possesses no mineral, gaseous or organic impurities. It is obvious that “pure water” as described in this paragraph is likely to found only in laborites…. And even there only under ideal conditions.
The source of water will by far define the pollution or impurities that it may hold.