Need In 12-14 Hours

1. on the topic of coagulation and flocculation: what are primary coagulants and what are coagulant aids? give two examples of each and explain when are they usually applied (water softening, color removal, etc).

2. During sedimentation, what is the main goal? can all the floc be removed? why?

3. sometimes a little bit of clay is added to improve flocculation, coagulation and sedimentation. What cases are appropriate for this to happen?

4. Contrast and compare: a slow sand filter, a rapid filter, a pressure filter and a diatomaceous earth filter. What type(s) is/are most commonly used in water utilities? why are slow filters not attractive then? give an example of diatomaceous earth filters use.

5. Slow sand filters, although not as popular, have seen good use over the years. They are not very efficient but have some particularities. One of them is called Schmutzdecke. What is this all about? why is it important that is present in a slow sand filter?

6. Two popular methods for disinfection in water utilities are chlorination and ozonization. Compare and contrast them. Where do we want to choose ozone over chlorine? explain

7. Describe what are membrane processes and electrodialysis. What are the main ideas behind these two?

8. In the water distribution process, what is a Clear Well? what considerations need to be taken into account for that?