Natural Sciences and Technology Grade 6 Term 2: Matter and Materials Processes to Purify Water (ppt 2)

Topic 6 Processes to Purify Water Treatment of Municipal Water Gr. 6 Natural Sciences and Technology – Term 2, Topic 6

How is water cleaned by municipalities? Tap water does not start off clean. The process of cleaning it is called water treatment. This usually happens in a water treatment plant. Gr. 6 Natural Sciences and Technology – Term 2, Topic 6

Water treatment Gr. 6 Natural Sciences and Technology – Term 2, Topic 6

Water treatment processes Water is treated through a number of processes such as: Step 1: Screening Screening for obvious pollutants – water passes through a screen that is like a huge sieve. Step 2: Settling Settling is when the water and other pollutants sink to the bottom of the tank. Gr. 6 Natural Sciences and Technology – Term 2, Topic 6

Water treatment processes Step 3: Aeration Aeration is when useful bacteria are used to break down pollutants and air is pumped into the water to keep the bacteria alive. Step 4: Filtering Filtering is when water is put through a filter of sand and gravel. Step 5: Disinfection Disinfection is when chemicals are added to the water to kill harmful germs. Gr. 6 Natural Sciences and Technology – Term 2, Topic 6