Electrochemical degradation of textile dyeing industry effluent in batch and flow reactor systems

Electrochemical oxidation of organic pollutants present in the dye-bath and wash water effluents from the textile industry was carried out in batch, batch recirculation and recycle reactor configurations under different conditions of current density, treatment duration, effluent flow rate and electrode specific surface. COD reduction of 52.63% to 82.61% could be obtained when the Procion blue dye-bath effluent was treated in the batch reactor for 8 h. In batch recirculation reactor, the reduction was 94.3% for dye-bath effluent and 91.4 for wash water effluent after 6 h of operation at a current density of 5.0 A dm−2 and flow rate of 100 L h−1. The specific energy consumption was found to be 4.32 kWh (kg COD)−1 for dye-bath effluent and 83.8 kWh (kg COD)−1 for wash water effluent. The results for wash water effluent under continuous operation of recycle reactor conditions showed 52.86% of COD removal at recycle flow rate of 100 L h−1 with discharge flow rate of 3 L h−1. The specific energy consumption was found to be 11.9 kWh (kg COD)−1.

► Dye effluent treatment was by electrochemical oxidation for COD removal.
► Treatment process examined in batch, batch recirculation and recycle reactor.
► The electrochemical mineralization enhances biodegradability.
► The specific energy consumption profiles suggest process integration.