Purification and Treatment of Water:

The basic purpose of water treatment system is to provide wholesome water that is aesthetically attractive, hygienically safe and palatable. The extent of treatment of raw water depends on the characteristics of water. There are various methods such as screening, sedimentation, coagulation, filtration, aeration, disinfection and softening, etc. for treating raw water independently or in combination depending on the quality of raw water, desired water quality standard and cost involved in various alternative treatment units. The present unit describes the various types of treatment that are commonly employed for bringing raw water to desired standards of quality.

Objectives

After studying this unit, you should be able to

• develop an overview of the important processes that are employed in treatment of water,
• define pre-treatment and list various treatments that are included in it, and
• describe various treatment processes such as sedimentation, coagulation filtration, disinfection and softening, etc.