Mia Kim

Practical field application of a novel BOD monitoring system.

A biochemical oxygen demand (BOD) monitoring system, based on electrochemically-active bacteria in combination with a microbial fuel cell, has been developed for the purpose of on-site, on-line and real-time monitoring of practical wastewater. A microbial fuel cell that had been enriched with electrochemically-active bacteria was used as the basis of the measurement system. When synthetic wastewater was fed to the system, the current generation pattern and its Coulombic yield were found to be dependent on the BOD5 of the synthetic wastewater. A linear correlation between the Coulombic yields and the BOD5 of the synthetic wastewater were established. Real wastewater obtained from a sewage treatment plant also produced a highly linear correlation between the Coulombic yield and BOD5 in the system. To examine on-site, on-line and real-time monitoring capability, the BOD monitoring system was installed at a sewage treatment plant. Over 60 days, the measurement system was successfully operated with high accuracy and good stability with the measuring period for a sample being 45 min. This application showed that the application of the measurement system was a rapid and practical way for the determination of BOD5 in water industries.

A Novel Combined Biomonitoring System for BOD Measurement and Toxicity Detection using Microbial Fuel Cells

Microbial fuel cell enriched with electrochemically-active bacteria using sludge was successfully applied as BOD and toxicity detection biosensors. The current from the microbial fuel cells was proportional to concentration up to 200 mg/L of BOD5 with high linearity. A microbial fuel cell could be also applied to a toxicity detection biosensor. An electric current signal change was observed in the presence of toxic substances (singular/complex) such as cadmium, lead, chromium(VI), mercury, cyanide, arsenic, PCB, organophosphorus and surfactant. By combining the principles of BOD measurement and toxicity detection, a novel biomonitoring system that could simultaneously monitor BOD concentration and the presence of toxic substances in aqueous system could be developed.

Seasonal Variations of Water Quality and Phytoplankton of 4 Lagoons in the East Coast of Korea

Abstract The seasonal variation of phytoplankton communities and its standing crops in accordance with environmental factors were investigated at Yeongrang-ho, Cheongcho-ho, Mae-ho and Hyang-ho which are located in the East coast of Korea during April to October 2011. High concentrations of T-N and T-P were observed in four lagoons due to the inflowing nutrients from farmlands and residential areas near lagoons. Nutrient salts mainly composed of nitrogen and phosphate caused the eutrophication of the lakes, leading to the robust growth of phytoplankton. During the period of investigation, 64 to 107 taxa of phytoplankton were observed in four lagoons. Diatoms were the most dominant species with high density. Non-point pollution source was estimated as the main cause of water pollution of lagoons. Trophic states of lagoons evaluated using the value of TSI and TSIKO indicated that all the investigated lagoons were in the eutrophication state.