• Journal of Korean Society of Environmental Engineers
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• v.36 no.11
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• pp.758-763
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• 2014

Soil microbial fuel cells (SMFC) have gained a great attention as an eco-friendly technology that can simultaneously generate electricity and treat organic pollutants from the contaminated soil. We evaluated the effect of electrode spacing and size on the performance of SMFC treating soil contaminated with organic pollutants. Maximum power density decreased with increase in electrode distance or decrease in electrode size, likely due to higher internal resistance. The maximum voltage and power density decreased from 326 mV and $19.5mW/m^2$ with 4 cm of electrode distance to 222 mV and $5.9mW/m^2$ with 9 cm of electrode distance. In case of electrode size test, the maximum voltage and power density generated was 291 mV, $0.34mW/m^3$ when both of anode and cathode area were $64cm^2$ with 4 cm of electrode distance. The maximum voltage decreased by 19~29% when the anode area decreased to $16cm^2$ while only 3~12% of voltage decreased with cathode area decrease. The maximum power density decreased by 49~68% with decreasing anode size, and by 29~47% with decreasing cathode size. These results showed that the anode area had more significant effects than the cathode area on the power generation of SMFC which has a high internal resistance due to a coexistence of soil and wastewater in the reactor.

• Journal of agriculture & life science
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• v.44 no.4
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• pp.79-85
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• 2010

An analysis in heating effects of an electric radiator located in a 1-2W type chrysanthemum (3 cultivars) cultivation greenhouse installed in Gyeongsang National University drew the following conclusions. During the experiment period, the highest, average, and the lowest outside temperatures were in the ranges of $-3.8{\sim}21.3^{\circ}C$, $-5.2{\sim}16.1^{\circ}C$ and $-12.5{\sim}14.4^{\circ}C$, respectively, and the average relative humidity inside and outside the greenhouses were in the ranges of 43.5~98.6% and 35.2~100%, respectively. From mid-December to early February, the lowest outside temperature was recorded as approximately $-5.0{\sim}-10.0^{\circ}C$, which showed that it tended to be relatively lower than the temperatures recorded at the Jinju Meteorological Observatory. During the night, the leaf temperature measured directly under the radiator tended to be higher by $2{\sim}3^{\circ}C$ than that those at the middle point of the radiator, or higher by a negligible amount. In the case of root zone temperature, it was found that there was almost no difference between temperatures of the part directly under and the middle point, and the time when the highest temperature of root zone and other highest temperatures took place showed that there was about a 2-hour delay phenomenon. The total electricity consumption, energy supply and total heating cost during the experiment period were 2,800 kWh, 2,408,000 kcal and 112,000 won, respectively. When diesel, a kind of fossil fuel, was used as heating oil, the total heating cost was around 224,500 won. It was estimated that the total heating cost could be reduced by around 50% if a radiator was used.