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First you will need some dirty water. Dissolving fine dirt into some water can do this. Let this set overnight to ensure that as much dirt as possible is dissolved.
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The next day, separate the water from the undissolved dirt by carefully pouring it into a clean, clear jar. (An old mayonnaise or mason jar works well.)
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The first step used in the water treatment process is aeration. We do this through powerful blowers that bubble air up through the water. This helps to remove any "fishy or earthy" odors and smells. Using a straw, blow into the water. Your lungs are your own powerful blowers.
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The next stage in the process is the rapid mixer. This is where we add our chemicals. In order to ensure that they are mixed thoroughly we have several high-speed mixers. You can use a spoon as your mixer. Be careful not to hit the sides of the glass too hard with your spoon, it could cause the glass to break.
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Once you have a whirlpool in your beaker from the stirring, you can add the chemicals. The treatment plant uses dry or liquid alum (aluminum sulfate)
or ferric chloride. You can buy alum in a weaker form in your local grocery store. It is used during the pickling process. The alum you buy comes in a dry form. You will have to experiment to see how much alum you need to add to your treatment plant. Remember, the more water you have the more alum you will need. Start out with a very small amount of alum (1/4 tsp). Add the alum into the center of the whirlpool. This will mix the chemicals fastest.
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Once the alum has been added, slow the stirring down. This is called coagulation. During this step you want to slowly stir the water (one circle every five seconds should be about right). Do this for about thirty seconds. You should notice some small floating particles forming in your jar. These are the floc particles. They are formed when the alum acts like a big magnet and attracts the negatively charged dirt particles.
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Now, remove your stirrer and let the water sit for about 10 minutes. You will notice that the floc particles you just formed will slowly sink to the bottom of the glass. This is called sedimentation.
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You can see that there are still particles in the top half of the water. You would not want to drink these,
so you will need to filter them. Take a funnel and place several wadded-up paper towels in it. Carefully, pour the top half of the water into the center of the funnel. Catch the clean water in a new bottle placed underneath the funnel. Look at how dirty the paper towels get.
We have to clean our sand and carbon filters, but it would be too expensive to put all new sand and carbon in the filter, so we do a backwash. This means that we force water up through the filter instead of letting it travel down. This water is then discarded.
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Now add one
to two drops of household bleach. This represents the disinfection stage
in the water treatment. We use chlorine. Household bleach contains
hypochlorite, which is a product of chlorine.
