Processes M.W.W.

 Back
Water treatment Engineering and Technologies
   

Website map

MUNICIPAL WASTE WATER TREATMENT (M.W.W.)

Secondary treatments - Aerobic processes

  • Fixed biomass reactors

    • one or two steps

    • on support in movement – biodiscs principle
    • on support without movement

      BIOFIX

  • Free floating biomass reactor (complete mixed)
    • one or more steps

      All processes mentioned below are compatible with further tertiary treatments (see "tertiary biological treatments")

      • single reactor for aeration

        Single bioreactor

      • two or more serial tanks (with or without flow inversion, periodically or in function of the pollution load)

        AERO-S

      • two or more parallel tanks (with eventually loading repartition in function of the chosen scheme)

        AERO-P

      • with or without "contact tank" (high load sludge recirculation tank in front of the aeration tank)

      • continuous process

      • SBR process ("sequencing batch reactor") – Waste water flows into the aeration tank only during the first period (some twenty hours) and aeration is performed. In the second period, without aeration, settling occurs in the same tank. A the end, part of the clarified water is discharged, followed by the removal of a small part of the sludge. Finally the cycle restart with aeration and waste water inlet.

    Tanks built in :

    • inox 304 or 316

    • concrete
    • steel (with coating, with galvanisation, ….)
    • ...

Position of the different tanks may be, regarding the erection possibilities :

  • concentrically
  • in one or more rows
  • ...

Supply of air by :

  • Surface aeration

    • low speed aerators

    • high speed aerators

  • Immersed diffusers

    • mechanically

    • compressed-air injection through immersed diffusers

      • with or without lifting possibility
      • fine or medium bubbles
      • hard or flexible porous material
      • with volumetric or centrifugal compressor
      • with or without horizontally forced flow
  • Secondary settling for clarification and sludge extraction

    • settling tank with sludge scraper

      • peripherally driving device

      • centrally driving device

    • settling tank with sludge suction system

    • settling in the same tank as the aeration

      • alternated periods of aeration and settling in a discontinuous process

        S.B.R. (Sequencing batch reactor)

      • alternated periods of aeration and settling in a continuous process

        ALTERCYCL A/D

Tanks, circular or rectangular, built in :

  • inox 304 or 316
  • concrete
  • steel (with coating, with galvanisation, ….)
  • ...
  • Secondary flotation for clarification and sludge extraction

    • Dissolved air flotation with indirect pressurisation

      HYDROFLOT - CLi

  • Clarification on porous membranes for clarification

    Water is separated from biomass by passing through porous membranes.

    • B.R.M. reactor with internal ultrafiltration membranes

      AERO-MiCl ("Réacteur Aérobie avec Membranes Internes de Clarification")

    • B.R.M. reactor with external ultrafiltration membranes

      AERO-MeCl ("Réacteur Aérobie avec Membranes Externes de Clarification")

    • B.R.T. reactor with textile membranes

      AERO-MtCl ("Réacteur Aérobie avec Membranes Textiles de Clarification")

  • Sludge recirculation :
    • with or without intermediate thickening
    • by centrifugal, volumetric or Archimedes pumps