Question

Explain the formation of sludge during wastewater treatment.

Answer 1

Wastewater treatment:

• The basic purpose of wastewater treatment is to eliminate as many suspended particles as possible before delivering the residual water to the environment as effluent.
• Primary, secondary, and tertiary water treatment are the three phases of wastewater treatment.
• Primary treatment removes around 60% of the suspended particles from wastewater.
• Secondary treatment removes more than 90% of suspended materials.

Primary wastewater treatment:

• Primary wastewater treatment entails the deposition of solid, semisolid, or slurry residual waste inside the water, which is called Sludge.
• This step is done after the water has been filtered to remove large pollutants.
• The water is then allowed to travel through tanks and filters to remove pollutants from the water. The resulting sludge is allowed to digest further.

Secondary wastewater treatment:

Secondary treatment of wastewater makes use of oxidation to purify wastewater further. This can be done in one of three ways:

1. Biofiltration: Sand, contact, or trickling filters are used in biofiltration to guarantee that more sediment is removed from wastewater.
2. Aeration: It is a lengthy but effective procedure that involves mixing wastewater with a microbial solution.
3. Oxidation Ponds: This strategy uses natural bodies of water such as lagoons. Wastewater is permitted to travel through this body for a while before being stored for two to three weeks.

Tertiary wastewater treatment:

The final stage is to purify the water supply of phosphates and nitrates. Activated carbon and sand are two of the most widely utilized elements that aid in this process.