UNIT 5 PROPOSAL

Running Head: WASTEWATER TREATMENT

WASTEWATER TREATMENT 2

FEEDBACK FROM INSTRUCTOR:

You need to include the whole thing from the Unit I.  

Also you need to pay attention to how to write pH.

Wastewater treatment

The two most used processes of water purification are the chemical and the biological processes. However, most of the purification methods that lie under the chemical and the biological means purify water only to about 95%. There is therefore a need to come up with a way to make the water totally clean and safe for use. This is where comes in flocculation, sedimentation and coagulation.

Coagulation is the process of compacting diffused impurities to form solid or semi solid lumps that can be filtered out of a solvent. The process mostly leads to a suspension being formed. Sedimentation process is the process where a solid is formed at the base of a liquid after separation with a liquid. Most of the time, settling the wastewater that was getting treated forms sediments. Flocculation is a process focused on removal of the suspension.

First, the PH of the wastewater needs to be established. This is done using a PH scale that ranges from zero to fourteen. If the Ph is less than seven, a basic solution needs to be added to the water to achieve a PH of seven. If has PH greater than seven, an acidic solution needs to be added to bring PH down to seven. The reactions that occur form salt and water, where the salt will be the metal precipitate.

Most of the flocculation processes that are done first by water are agitation or the addition of the flocculation agent. The use of the water has to be considered carefully before flocculation. Some of the flocculation agents added are toxic and are used for water that is not for human consumption but other industrial use. They have to be used based on the particles to be removed in the wastewater. Secondary clarifiers should have an energy dissipater inlet to avoid disturbance of the elaborate sedimentation. Sludge withdrawal system is important to keep the clarifier as less clogged as possible and finally have a full surface skimmer.