Aerobic  treatment  of  waste water  requires  the  continuous  replenishment of  oxygen  economically  in  sufficient  quantities.  Efficient  aerators  are developed  towards  this  end.  Plunging  Hollow  Jet Aerators  consist  of  a cone,  which  deflects  the  water  at  the  end  of  a  discharging  pipe  through the annular opening, forming a hollow jet.  The thin jet striking the water in the aeration tank formed a circular wave front creating high turbulence and  entraining  large  quantities  of  air.  The  efficiency  of  the  device  was high  (1.5  to  2,25    kg./  kW.h)  under  standard  conditions, for the small opening between the pipe and the cone. But this method can be used only when the water does not have solids which may  clog  the  openings.

Venturi  and  Sudden  Expansion  type Aerators

Wastewater  from  the  aeration  tank  is  drawn  by  a  pump  and  discharges towards  the  bottom  of  the  tank  after  passing  through  an  air  aspirating device.  It  could  be  a  Venturi  or  sudden  expansion  downstream  of  which air  is  admitted.  Experiments  have  shown  that  such  devices  can  have high  oxygenation  efficiencies  of  1.5  to  2.25  kg  /.kW.h  under  standard conditions.  These  devices  can  be  used  without  fear  of  clogging  due  to solids  in  the  wastewater.  The  performance  in  model  is  shown  in Photograph  attached.  The  devices  can  be  used  very  efficiently  even  in small  package  wastewater  treatment  plants. The  sudden  expansion  air  aspirating  aerators  are  being  used  in  a  new waste  water  treatment  plant  in  the  Ettimadai  campus.

Project Details
Dr. K.M. Mini
Dr. N. Narayana Pillai
Start Date: 
Wednesday, May 1, 2013


Funding Agency: