Primary treatment

Primary treatment is the first phase of wastewater treatment and involves the removal of large, easily visible debris and solid particles from the wastewater. This process is typically achieved through the use of physical processes such as sedimentation and filtration.

Process

The primary treatment process begins with the wastewater being directed into a large tank known as a primary clarifier. Here, the wastewater is allowed to sit undisturbed for a period of time, allowing the solid particles to settle to the bottom of the tank. These solids, known as sludge, are then removed from the tank and further treated or disposed of.

The remaining wastewater, now relatively free of solid particles, is then moved on to the next phase of treatment, known as secondary treatment.

Efficiency

Primary treatment is capable of removing approximately 50-70% of the total suspended solids (TSS) and 25-50% of the biochemical oxygen demand (BOD) from the wastewater. However, it is not very effective at removing pathogens, nutrients, or dissolved organic matter.

Limitations

While primary treatment is an important first step in the wastewater treatment process, it is not sufficient on its own to produce water that is safe for discharge into the environment. Additional treatment steps, such as secondary and tertiary treatment, are necessary to further reduce the levels of pollutants in the wastewater.

See also

• Wastewater treatment
• Secondary treatment
• Tertiary treatment
• Sludge

Primary treatment Resources
Latest articles Most recent articles Ongoing trials	Wikipedia