HYDROPLUME -A high Rate Secondary Clarifier for waste water treatment

Conventional secondary clarifiers can have problems regarding the hydraulics of incoming flow, so a new novel clarifier called the Hydroplumehas been developed to optimize inflow and sludge settlement. In the activated sludge process the quality of the effluent,to a large extent, depends on how efficiently
the biological sludge mass is separated from the treated wastewater.The solids-liquid separation traditionally takes place through the separation of spontaneously aggregated flocs of activated sludge by gravity sedimentation in secondary clarifiers.Therefore,secondary clarifiers combine the functions of: a thickener to thicken the returned sludge to the required concentration; a clarifier to produce a clear effluent; and a storage tank to store sludge during peak flows. The design of conventional secondary clarifiers does not take hydraulic energy dissipation into account,hence they are either too large or often fail to ensure efficient solids -liquid separation.Therefore,the key issue is to improve the hydrodynamics of the secondary clarifier by optimizing the velocity gradient and hydraulic energy dissipation to ensure natural flocculation to enhance the solidsliquid separation. HYDROPLUME has potential application in solids –liquid separations in WTPs, ETPs, STPs and CETPs


IPR Status

  • USA (No. 7637379)
  • Europe (No. EP 2091624)
  • South Africa (No. 2008/07739)
  • India (Application No. 2623 Del 2006)



  • Dr. Girish Pophali
    Wastewater Technology Division


IPR Status

  • Patent draft in progress with minor improvements. Sent to BDTT for final approval and the same will be sent to CSIR on or before July 31, 2017.

Salient Features

  • Improved solids-liquid separation ensures minimum suspended solids (SS) concentration in the treated effluent
  • It requires minimum hydraulic retention time (1 – 1.5 hours) and saves at least of 25 – 30% foot print area thereby facilitates up to 40% savings in capital and recurring costs
  • It produces excellent effluent quality (98 – 99% SS removal) and helps in attaining the treated effluent quality according to the prescribed discharge standards
  • High underflow solids concentration minimizes pumping rate, and maintains desired active biomass concentration in aeration tank
  • HYDROPLUME does not require a separate sump cum pump house for sludge recycling/removal, thereby saves capital and recurring costs
  • HYDROPLUME provides natural flocculation and does not require separate flocculation facility, thereby reduces capital
  • Included in MOUD’s CPHEEO revised manual on ‘Sewerage and Sewage Treatment’, 2012