Treatment of strained yoghurt wastewater by electrochemical oxidation method using Taguchi experimental design

Abstract

In this study, the efficiency of different electrode pairs in the treatment of strained yoghurt wastewater with electrochemical oxidation method and the operating conditions in the reactor (distance between electrodes and applied potential) in specific energy consumption (SEC) for COD removal were investigated by applying the Taguchi experimental design and ANOVA analysis. For different electrode pairs, the highest COD removal was obtained as 24.79-28.9%, and it was observed that the electrode type did not have a significant effect on organic matter removal. It has been found that the operating conditions for different electrodes show similar trends for SEC in COD removal. The applied potential for all electrodes was determined as the most effective operating condition, followed by the reaction time and the distance between the electrodes. According to the results of ANOVA, the correlation coefficients of different electrode pairs were determined in the range of 82.33-91.21% for the SEC in COD removal. SEC under the studied experimental conditions is between the following values: 0.0019-2.5695, 0.0011-0.5702, 0.0007-0.5721, and 0.012-0.3641 kW h kg COD-1 for steel (anode)-steel (cathode), graphite (anode)-graphite (cathode), graphite (anode)-steel (cathode), and BDD (anode)-graphite (cathode) electrode pairs, respectively. It is thought that the electrochemical oxidation process will be a good alternative treatment method for strained yoghurt wastewater, which has a very high COD content and low pH value, as a post-treatment unit or in combination with other methods, due to an effective COD removal at low reaction times and low SEC. [GRAPHICS] .