ECUVal is especially efficient for the treatment of effluents with high colouration and high conductivity values, such as the exhausted dyebaths and washing effluents from the reactive dyeing process. ECUVal uses the residual salts present in the effluents to generate oxidants which break down the dye molecules.
ECUVal system can operate in two modes:
Decolouration mode: The effluents are decolourised by means of the ECUVal system and then are discharged to the wastewater treatment plant in order to achieve the full elimination of the residual organic matter. In this mode, the ECUVal treatment is an alternative to the current tertiary methods used for colour removal.
Reuse mode: ECUVal is equipped with an automated system to reconstitute the uncoloured effluents before being reused. The reconstitution is carried out in the following steps:
The reconstitution is carried out in the following steps:
- Removal of carbonate and bicarbonate by adding acid and subsequent stripping.
- Neutralization of the effluent by adding alkali.
- Removal of residual oxidants by UV irradiation and addition of a reducing agent.
At the end of this step, water suitable for reusing in the dyeing process is obtained.
Industrial tests have demonstrated that the ECUVal system is a flexible and versatile treatment that provides excellent results both for colour removal and for reuse purposes. Consequently, ECUVal solves the problem of effluent colouration and enables the reuse of water and salts in new dyeing processes with a low energy consumption:
Examples of exhausted reactive dyebaths from jet processes treated with the ECUVal system.