22
C. Gutiérrez-Bouzán et al.
Fig. 17 ReCipe midpoint characterisation values for the three scenarios
Some textile companies use mixtures of Na 2 CO 3 and NaOH to adjust the pH.
Based on this, a new LCA was performed considering the total replacement of
Na 2 CO 3 by NaOH. In comparison to the conventional process (Scenario 1), the
use of the system running in decolourisation mode (Scenario 2 with NaOH instead
of Na 2 CO 3 ) decreases by 20% the environmental impact, whereas the reuse of water
and salt (Scenario 3) by 60%.
9 Conclusions
The EC-UV system, based on the degradation of dyes by combining an electrochemical process with UV radiation, has demonstrated to be an innovative and interesting
process for its application in the textile industry.
The EC-UV system has significant advantages with respect to the methods
currently used for the treatment of textile wastewater:
• EC-UV is able to treat the more coloured and with high salt content effluents.
• No chemicals are required to carry out the electrochemical process.
• The only cost of the EC-UV treatment is the electric power supply.
• No wastes are produced.
• As the high coloured effluents are segregated to the EC-UV system, the tertiary
treatment for colour removal can be supressed in the wastewater treatment plant.
This results in a significant reduction of reagents and sludge disposal costs.
• Discharge taxes are lowered due to the reduction of wastewater salinity.
• The system does not need maintenance since the electrodes are very stable and
can be used over 5–10 years.
• Less cost in water due to the reuse of 70–100% dyeing water
• Less cost in salt as a consequence of reusing the treated effluents that still contain
salts. Savings up to 100% salt can be achieved.
C. Gutiérrez-Bouzán et al.
Fig. 17 ReCipe midpoint characterisation values for the three scenarios
Some textile companies use mixtures of Na 2 CO 3 and NaOH to adjust the pH.
Based on this, a new LCA was performed considering the total replacement of
Na 2 CO 3 by NaOH. In comparison to the conventional process (Scenario 1), the
use of the system running in decolourisation mode (Scenario 2 with NaOH instead
of Na 2 CO 3 ) decreases by 20% the environmental impact, whereas the reuse of water
and salt (Scenario 3) by 60%.
9 Conclusions
The EC-UV system, based on the degradation of dyes by combining an electrochemical process with UV radiation, has demonstrated to be an innovative and interesting
process for its application in the textile industry.
The EC-UV system has significant advantages with respect to the methods
currently used for the treatment of textile wastewater:
• EC-UV is able to treat the more coloured and with high salt content effluents.
• No chemicals are required to carry out the electrochemical process.
• The only cost of the EC-UV treatment is the electric power supply.
• No wastes are produced.
• As the high coloured effluents are segregated to the EC-UV system, the tertiary
treatment for colour removal can be supressed in the wastewater treatment plant.
This results in a significant reduction of reagents and sludge disposal costs.
• Discharge taxes are lowered due to the reduction of wastewater salinity.
• The system does not need maintenance since the electrodes are very stable and
can be used over 5–10 years.
• Less cost in water due to the reuse of 70–100% dyeing water
• Less cost in salt as a consequence of reusing the treated effluents that still contain
salts. Savings up to 100% salt can be achieved.