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SANITATION
 SANIT A TION


 Ÿ To meet the water requirements of units coming up   state-of-the-art  GE  Membrane  Technology  (ultra   followed  by  Flocculation-Clarification  in  Claritube   the Moving Bed Biological Reactor.
 inside Mangalore SEZ, Mangalore SEZ Ltd (MSEZL)   filtration)  for  re-use  of  Secondary  Treated  Sewage   Flocculator (CTF).   Claritube Flocculator (CTF):
 was provided with the wastewater from 3 STPs as one   Water from Kavoor STP during the year of 2011.   Ÿ Filtration by Membrane-based Ultrafiltration system.
 of  the  sources.  Since  the  Netravathi  river  is  being   Ÿ State-of-the-art plant with process automation and the   Ÿ The  Sewage  from  MBBR  flows  to  the  Claritube
 utilized for drinking purposes, drawing of additional   plant is being controlled and monitored through PLC-  Ÿ Disinfection using ClO2 with onsite ClO2 unit.   Flocculator. At the inlet of CTF alum is dosed in the
                                                                 flash mixer. The solids separated here are settled and
 water  was  not  allowed  from  the  river  hence  the   based SCADA system.   Ÿ Sludge handling Filter Press Unit.   the sludge formed is withdrawn from the Claritube
 MSEZL had to settle with the wastewater from 3 STPs   Ÿ The tertiary treated sewage is then stored in a tank,
 Ÿ Plant  is  commissioned  and  MSEZL  is  supplying            Flocculator which is taken to the sludge sump.
 as one of the Sources.   from where it is pumped to SEZ area.
 treated  water  to  MRPL/MSEZL  from  November               Ÿ The Claritube Settler comprises of Tube settler formed
 Ÿ Several meetings were carried out with MSEZL and
 2012.   Stilling Chamber:                                       by specially designed Tube Modules. In tube settler
 formed SPV-Mangalore STP Limited for reusing the
 secondary treated sewage water.   Ÿ Tertiary  Treatment  Plant  is  mainly  designed  for   The treated sewage outlet from the existing STP is raw   the effective surface area required for the separation of
 removal of TSS, turbidity and for further reduction of   water for Stilling Chamber (SC), where the turbulence is   suspended solids is provided in relatively much less
 Mangaluru  City  Corporation  has  provided  the  below   reduced. The sewage pumped to Stilling Chamber with   volume compared to conventional clarifiers.
 BOD & COD from secondary treated sewage water.
 mentioned civil & mechanical structures and handed over   1162m3/hr to the downstream units.   The Tube settler is divided into four zones.
 to SPV.   Ÿ The designed parameter of TTP is given in the table   Moving Bed Biological Reactor (MBBR):
 1. Inlet Chamber  below.                                     Ÿ  Distribution zone
         Ÿ The  main  pollutants  in  the  treated  sewage  are   Ÿ  Inlet zone
 2. Screen Removal
 Parameter of TTP  represented  in  the  form  of  Biochemical  Oxygen   Ÿ  Settling zone
 3. Grit Chamber    Demand  (BOD)  and  Chemical  Oxygen  Demand
                                                              Ÿ  Discharge zone
 4. Parshall Flume   Sl.   Parameter  Unit  Inlet  Outlet  (COD).   Ultra filtration:
 No.
 5. UASB   Ÿ The  bio-reactions  are  carried  out  in  the  controlled
 1.  pH  -  6.5-7.5  7.0-7.5  environment  in  the  Moving  Bed  Bio-Reactor   Ÿ The clear overflow from CTF gravitates through the
 6. Preaeration                                                  UFC  channel  to  UFMT.  ZW-1000  UF  Membrane
 2.  TSS  mg/l  30  < 1  (MBBR). The bioreactor comprises of a tank, fitted
 7. Aeration                                                     system is used for treating the clarifier outlet water.
 0
 3.  BOD5 at 20  C  mg/l  20  <2  with  an  aeration  grid.  The  bacterial  activity  needs   The basic purpose of the UF system is to remove the
 8. Clarifier    dissolved oxygen, to synthesize the organic matter.
 4.  COD  mg/l  100  < 30                                        fine colloidal impurities and thereby removes BOD.
 9. CCT- Let off natural drains   This  is  supplied  by  passing  air  in  form  of  small
 5.  Nitrogen  mg/l  15 (Total   < 5   bubbles.               Ÿ The complete UF system is automated and processes
 10. Thickener & Sludge Recirculation
 Nitrogen)  (Ammonical                                           are typically operated in the following modes.
 11. Drying Bed  Nitrogen)  Ÿ The air is passed at the bottom of the tank so that the
           complete  volume  of  the  tank  is  utilized.  Dissolved   -   Permeation
 The treatment Process Involves:   6.  Fecal Coliform  MPN  -  <1/100ml
           oxygen can be used by the bacteria.                    -   Backwash
 Tertiary Treatment Plant   7.  Turbidity  NTU  -  <0.5           -   Maintenance Clean (MC)
         Ÿ The  bacterial  population  is  present  on  the  media,
 Ÿ MSEZL  has  taken  up  the  construction  of  5  MGD   which forms an integral part of the reactor system. The   -   Recovery Clean (RC)
 Advantage of TTP water reuse
 (22.7MLD)  Tertiary  Treatment  Plant  (TTP)  using   media is made of small plastic elements. Millions of   -   Stand-by
 Ÿ Reduction  in  the  dependency  on  natural  water
           such pieces are present in the reactor.                -   Shutdown
 resources.
         Ÿ A very large surface area is available for the bacterial   Disinfection System:
 Ÿ Reduction  of  financial  burden  on  Mangalore  City   population to grow. The bacteria grow on the plastic   Ÿ The treated filtered sewage is then added with ClO2
 Corporation for O&M of STP.   media by using the organic content in the raw sewage   for Disinfection. Chlorine Dioxide is generated using
 Ÿ Avoiding  disposal  of  secondary  treated  sewage  in   and the dissolved oxygen available. Due to constant   Acid Chlorite technology.
 natural river body thereby minimization of pollution   aeration, the media is set in whirling motion so that   Sludge handling:
 loads  on  freshwater  sources  and  improving   continuous mixing takes place.
                                                              Ÿ The  sludge  from  the  Claritube  Flocculator  (CTF)
 Environmental quality.   Ÿ The  bacterial  layer  growth  on  the  media  surface
                                                                 flows to Sludge Sump (SC) and then it is pumped to
 Ÿ Employment generation.   increases to a certain extent and then gets sloughed off   Filter Press (PS) for Solid Liquid Separation.
           after a specific period.
 Tertiary Treatment process:                                  Ÿ The dewatered sludge is further used for Green Belt
         Ÿ Around 60% to 70% of the BOD is further reduced in
 Ÿ Biological  treatment  comprising  of  Aerobic                development.
 Treatment  in  Moving  Bed  Bio-Reactor  (MBBR)              Final Storage Tank:
 STP and TTP Flowchart
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