General

The activated sludge pilot allows the study and the comprehension of sewage treatment by activated sludge.

This treatment is an intermediate stage between the physical treatments or gridiron, defoliation and primary sedimentation And the final sterilization and chlorination stage, in a sewage treatment station. Its purpose is to eliminate the contaminated

The clarified water flows down to the receiving body, or to a sterilization treatment, while the activated sludge is partially recycled within the oxidation tank in order to stabilize the elimination treatment.

This pilot plant has been designed to enable the students to learn all the fluid-dynamic, chemical-physical problems arising from the realization of an activated sludge process.

Organic substances which are present in the sewage water after the above mentioned physical treatment.

The organic load is measured in BOD (Biological Oxygen Demand) unit and it also causes a partial elimination of COD (Chemical Oxygen Demand). The micro-organisms utilize the contaminated substances as necessary food for their production and their preservation. The aspect for this mass of micro-organisms is that of sludge, from which we have taken the name of the Process. The conditioning process takes place in a tank where the organic load is removed by microorganism (bacteria, rotiferal, vorticella, etc.) which are cultivated under aerobic conditions by blowing in air or sometimes also pure oxygen. After the pollutant elimination phase it is necessary to divide the clarified water from the sludge, operation which is Carried out in the settling tank (stating separator).

The unit is completely instrumented and arranged for the execution of tests that help to understand advanced problems which come from the modern conception of activated sludge plants such as:

The energetic saving and the reliability of the sludge recirculating system by “air-lift

The effect of the work oxygen concentration on the sludge elimination and sedimentation.

The agitation effect in the reaction tank.

Range of Experiments:

Evaluation of the effect at different concentrations of dissolved O2.

Determination of the sludge sedimentation varying the concentration of work 02.

Determination of the purification effect according to the feed hydraulic stay time in the oxidation tank.

Determination of the purification effect according to the mixing.

Influence of sludge age.

Influence of the activated carbon on the purification process.

Influence of pH.

Efficiency of the purification according to the temperature.

Tests using O2 instead of air.

Required services:

Electrical supply: 220V – 50/60 Hz – 3 kW 

Compressed air supply: 800 l/h – 6 bar

Water supply: 200 l/h – 2 bar.

Dimensions and weights

Dimensions: with feed tank 2450 X 700 X 1700 h mm 

Net weight: 270 Kg.