High Rate Solids Contact Clarifier (HRSCC)

HRSCC stands for High Rate Solids Contact Clarifier, which is a type of clarifier use in wastewater treatment. It is design to achieve high removal efficiencies of suspend solids and other impurities in a compact and efficient manner.

Process Steps & Key Functions

Solids Contact Zone: The HRSCC includes a solids contact zone where the wastewater is mix with chemicals, such as coagulants and flocculants. The mixing promotes the formation of flocs and facilitates the interaction between the chemicals and the suspend particles.

Flocculation Zone: After the solids contact zone, the wastewater flows into a flocculation zone, where gentle mixing is provide to enhance the growth and development of flocs. This helps in the aggregation of suspend particles into larger, settleable flocs.

Sedimentation Zone: Following the flocculation zone, the wastewater enters a settling zone within the HRSCC. This zone allows the settleable flocs to separate from the liquid and settle to the bottom of the tank under the influence of gravity.

Sludge Collection: The settle flocs form a layer of sludge at the bottom of the HRSCC, which is periodically collect and remove using sludge rakes or other mechanisms. The collect sludge is then direct to further treatment or disposal processes.

After the flocculation stage, the water proceeds to the settling stage within the same tank. The velocity of the water flow is reduce, allowing the form flocs to settle to the bottom of the tank by gravity. The settle particles, along with the form sludge, are collect and remove as sludge from the tank.
The clarifie water, known as the supernatant, is collect from the upper part of the tank, typically using a collection mechanism or launder system. It is then further treat through processes such as filtration, disinfection, or other advance treatment methods to achieve the desire water quality.


HRSCC units are known for their ability to handle high hydraulic loading rates, allowing for a greater flow of wastewater through the clarifier. This, combine with the efficient mixing and flocculation processes, results in a compact design and improve treatment efficiency.
The high rate of solids contact and the enhance mixing and settling processes in HRSCC units enable them to achieve high removal efficiencies for suspend solids, organic matter, and other impurities. They are commonly use in wastewater treatment plants where space is limit, but high-quality effluent is still require.

Targeted Impurities

  • TSS
  • Turbidity
  • BOD
  • Colloidal Particles
  • Partial Color
  • grit
  • Chemical Sludge
  • Hardness
  • Heavy Metals