Activated Sludge Process CE 705

Activated Sludge Process

Type: CE 705
Name: Activated Sludge Process
CE 705 - A product from the GUNT 2E range
Technical Description

  The activated sludge process is the most important biological process in water treatment. CE 705 enables this process to be demonstrated.
  A pump delivers raw water contaminated with dissolved organic substances (organic matter) into the aeration tank. Aerobic microorganisms (activated sludge) in the aeration tank use the organic matter as a source of nutrition, biodegrading it in the process. Since aerobic microorganisms need oxygen, the raw water is aerated in the aeration tank. The activated sludge is mixed with the raw water by stirring machines. In the secondary clarifier the activated sludge is then separated from the treated water by sedimentation. A portion of the activated sludge is returned to the aeration tank (return sludge). The treated water is collected in a tank.

  It is also possible to convert ammonium into nitrate (nitrification) and nitrate into nitrogen (denitrification). For denitrification a zone without aeration can be created in the aeration tank by installing a partition wall.
  The following flow rates are adjustable: raw water, return sludge, internal recirculation for pre-denitrification and air. Oxygen concentration, pH value and temperature can be contolled.

  A software program is provided to display the operation states and measure data. A process schematic shows the current operating states of the individual components and the measured data.

  Samples can be taken at all relevant points. Activated sludge from a wastewater treatment plant and analysis technology are required for the

experiments. Recommended parameters are:

- BOD5 (biochemical oxygen demand)

- COD (chemical oxygen demand)

- NH4 (ammonium)

- NO3 (nitrate)


  The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

Learning Objectives / Experiments

- learning the fundamental principle of the activated

  sludge process
- functional principle of nitrification and pre-


- creation of a stable operating state

- identification of the following influencing factors
  * return sludge ratio

  * return ratio of the internal recirculation

  * sludge age

  * sludge loading

  * volumetric loading

  * oxygen concentration, pH value and temperature

- efficiency of the pre-denitrification


* Wastewater treatment plant in laboratory scale1

* Aerobic biological degradation of organic

* Nitrification and pre-denitrification

CE 705 Activated Sludge Process

[1] biological wastewater treatment

[2] aeration tank with 3 stirring machines

[3] secondary clarifier
[4] nitrification and pre-denitrification
[5] separate supply unit with 2 stirring machines
[6] all relevant flow rates adjustable
[7] control of temperature, pH value and oxygen concentration

[8] measurement of flow rate, temperature, pH value and oxygen concentration
[9] GUNT software with display of the operation states and data acquisition via USB under Windows Vista or Windows 7

[10] visual inspection with webcam on PC

Technical Data

Aeration tank
- capacity nitrification zone: approx. 34L

- capacity denitrification zone: approx. 17L

- secondary clarifier: 30L

- raw water tank: 200L
- treated water tank: 80L
Flow rates

- raw water pump: max. 25L/h

- return sludge pump: max. 25L/h

- circulation pump: max. 25L/h

Speeds (stirring machines)

- secondary clarifier: max. 45min-1
- all others: each max. 600min-1


Measuring ranges
- flow rate (raw water): 2...25L/h
- flow rate (compressed air): 50...550L/h
- temperature: 0...40°C
- pH value: 0...14
- oxygen concentration: 0...10mg/L

Dimensions and Weight

LxWxH: 1550x790x1150mm (supply unit)

LxWxH: 2830x790x1900mm (trainer)
Weight: approx. 450kg

Required for Operation

230V, 50/60Hz, 1 phase or 120V, 60Hz, 1 phase

Water connection, drainage, activated sludge, substances for preparation of artificial wastewater, caustic soda, hydrochloric acid

Scope of Delivery

1 trainer
1 supply unit

1 set of hoses
1 GUNT software CD + USB cable

1 webcam

1 measuring cup
1 stopwatch
1 beaker
1 set of instructional material

Order Details

083.70500  CE 705  Activated Sludge Process