HOW TO REMOVE GASES FROM WATERS, AS CORROSIVE TO METALS AND POISONOUS IN CONCENTRATION

GASES IN WATER:-- (CARBON DIOXIDE) :- It is trouble some of all the gases present in the waters. It is dissolved by water from the atmosphere from de-composing organic matter. Its presence encourages the formation of bicarbonates of calcium and magnesium carbonate. Natural water containing carbon dioxide will dissolve various mineral salts while flowing through the ground which give hardness, alkalinity and saltish taste to the water. Such waters cause heavy and rapid corrosion of unprotected pipes, or deposit a film of carbonate. Carbon dioxide may also stimulate heavy growth of algae , if water is exposed to sunlight. Excess carbon dioxide can be removed by aeration or by addition of lime. To prevent corrosion and scale due to water containing carbon dioxide and bicarbonate alkalinity it may be passed through a bed of marble stones or limestone chips. This process is simple and requires no special equipment and the carbon dioxide is used to reduce the pH values and to liberate hydrogen sulphide from sulphur waters. (2) HYDROGEN SULPHIDE :- gas gives objectionable smells, has rotten egg odour. It attacks cement and concrete and destroy sto