Waste water treatment

Waste water treatment represents the set of all the physical, chemical, biological and bacteriological procedures that reduce the water charged with polluting substances : organic or inorganic and bacteria. Result : clean waters, with different degrees of purification, depending on the technologies and the equipment used, as well as separated residues : under solid form and sludge.

In the field of domestic and industrial waste waters treatment, our company’s activities include :
    - advisory services ;
    - the elaboration of treatment technologies ;
    - the performance of feasibility studies ;
    - the preparation of technical designs ;
    - the technology updating of the existing plants ;
    - building of new waste water treatment plants;
    - technical expertises ;
    - the manufacturing of parts and equipment for waste water treatment ;
    - the commissioning of waste water treatment plants and the setting of the exit water according to the parameters ;
    - the operators’ training for waste water treatment plants.

The technologies elaborated by our company include physical-chemical and biological treatment processes comprising the following kinds of treatment :

The mechanical treatment aims at removing the settlable solid matters and the floatable or semi-floatable ones, whatever their organic or inorganic nature. The typical methods used at this level are the gravitational separation, decantation and floatation. The removing efficiency amounts to 40–60% for the solid suspensions and around 30% for the organic charge expressed in CBO5, without however the reduction of nitrogen or phosphorus based compounds.

The biological treatment aims at removing the soluble organic substances – in a colloidal condition or as fine suspensions, which could not be retained in the physical stage – and those specially added, such as active sludge. The biological purging processes are based on the metabolic activity of certain groups of micro-organisms that mineralise the organic substances to carbon dioxide and water. The separation efficiency is 80–90% for the organic charge expressed in CBO5 and around 10 % for the compounds based on nitrogen and phosphorus.

The advanced treatment aims at removing the compounds based on nitrogen and phosphorus, which contribute to the eutrophisation of the natural tanks but also other specific pollutants existing in the amount of water in suspension and of the active sludge within the process of extended aeration. The removal of phosphorus by the chemical process of precipitation-coagulation-flocculation brings forth its reduction by 80-90%. The elimination of the nitrogen-based compounds by the biological process of nitrification–denitrification may reach a 90% yield.

The disinfection of the treated water aims at destroying the pathogenic germs and it can reach a 98–99% efficiency. This is achieved by using chlorine, chlorine dioxide, ozone or UV radiations.

The applied technologies are highly flexible from the standpoint of the flow rates and the entrance parameters of the used waters, of the automated operation with the possibility of integration into SCADA systems, of the high reliability and by a quick efficient maintenance system by on-line monitoring.