• Journal of Korean Society of Water and Wastewater
• /
• v.26 no.3
• /
• pp.409-421
• /
• 2012

Ethanolamine (ETA) is mainly used to prevent corrosion of pipe in secondary cooling system of nuclear power plant. Condensed ETA in wastewater could increase COD and T-N when it was emitted to natural water system. Compared to conventional treatments, electrochemical oxidation process using packed bed bipolar electrodes was adopted to treat COD and T-N. According to arrangement of feeder electrode, single packed bed bipolar electrode reactor and multi-paired packed bed bipolar reactor were developed and conventional zero-valent iron (ZVI) was selected as conducting bipolar electrode. Bipolar electrodes were coordinated three-dimensionally in the reactor. The experimental results showed that COD and T-N was little removed in unit system at different pH condition (pH 8 and 11) on 100V. However, in multi-paired system that applied 600V, COD was eliminated 80.85% (anode-cathode-anode, A-C-A) and 85.11% (cathode-anode-cathode, C-A-C), respectively. T-N was also removed 96.88% (A-C-A) and 90.63% (C-A-C), simultaneously. Current efficiency was estimated both single and multi-paired system. At unit bipolar packed bed reactor, current efficiency was almost zero, however in multi-paired system, current efficiency was 300~500% at A-C-A and 250~350% at C-A-C. Current efficiency was over 100% hence it was confirmed that this system is more effective than conventional electrochemical oxidation system.

• Journal of the Korean Electrochemical Society
• /
• v.2 no.1
• /
• pp.13-16
• /
• 1999

A mathematical analysis of bipolar electrode reactor model for complex electrochemical reactions could estimate total current from time-concentration data, which coincided well with experimental total current data. Thus behaviour of bipolar electrode reactor could be described by a proposed simulation model. This paper demonstrates how such a model can be used a useful tool in the design for pilot plant experimentation.

• Applied Chemistry for Engineering
• /
• v.3 no.4
• /
• pp.657-662
• /
• 1992

For describing the bipolar packed-bed electrode cell filled with graphite pellete electrode, the application of the model of equivalent circuit was studied. The ratio between the Faradaic current through bipolar electrodes and the applied current was dependent on the resistance coefficient, specific conductivity of electrolyte, and electrolyte circulation rate. The ratio of the Faradaic current through bipolar electrodes to the applied current increased with the applied current(or cell voltage), but decreased with the increase of electrolytic conductivity and circulation rate of the electrolyte.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.2B
• /
• pp.187-192
• /
• 2011

Nitrate nitrogen is common contaminant in groundwater aquifers, its concentration is regulated many countries below 10 mg/L as N (As per WHO standards) in drinking water. An attempt was made to get optimal results for the treatment of nitrate nitrogen in groundwater by conducting various experiments by changing the experimental conditions for ZVI bipolar packed bed electrolytic cell. From the experimental results it is evident that the nitrate nitrogen removal is more effective when the reactor conditions are maintained in acidic range but when the acidic environment changes to alkaline due to the hydroxide formed during the process of ammonia nitrogen there by increasing the pH reducing the hydrogen ions required for reduction which leads to low effectiveness of the system. In the ZVI bipolar packed bed electrolytic cell, the packing ratio of 0.5~1:1 was found to be most effective for the treatment of nitrate nitrogen because ZVI particles are isolated and individual particle act like small electrode with low packing ratio. It is seen that formation of precipitate and acceleration of clogging incrementally for packing ratio more than 2:1, decreasing the nitrate nitrogen removal rate. When the voltage is increased it is seen that kinetics and current also increases but at the same time more electric power is consumed. In this experiment, the optimum voltage was determined to be 50V. At that time, nitrate nitrogen was removed by 94.9%.