Most food waste is incinerated and reclaimed in Korea. Due to the development of industry, soil and groundwater pollution are serious. The purpose of this study was to study recycled materials and eco-friendly remediation methods to prevent secondary pollution after remediation. In this study, recycled food waste ash was filled in a permeable reactive barrier (PRB) and used as a heavy metal adsorption material. In situ remediation electrokinetic techniques (EK) and acetic acid were used. Electrokinetic remediation is a technology that can remove various polluted soils and pollutants, and is an economical and highly useful remediation technique. Thereafter, the current density increased constantly over time, and it was confirmed that it increased after electrode exchange and then decreased. Based on this result, the acetic acid was constantly injected and it was reconfirmed through the water content after the end of the experiment. In the case of both heavy metals, the removal efficiency was good after 10 days of operation and 8 days after electrode exchange, but, in the case of lead, it was confirmed that experiments are needed by increasing the operation date before electrode exchange. It was confirmed that the copper removal rate was about 74% to 87%, and the lead removal rate was about 11% to 43%. After the end of the experiment, a low pH was confirmed at x/L = 0.9, and it was also confirmed that there was no precipitation of heavy metals and there was a smooth movement by the enhancer and electrolysis after electrode exchange.
We present a high efficiency (η~18.5%) mono-crystalline Si solar cells (A=15.6×15.6cm 2 ) with a selective emitter structure using a conventional diffusion process (POCl 3 ) and screen printed contact. Especially, in this paper, we focus on the improvement of Voc by selective emitter pattern optimization. As a result, we improve about 4mV Voc as a function of heavy emitter area, investigate the cause of the Voc increase by internal quantum efficiency and life time. The fabricated solar cell with selective emitter has accomplished Voc 635.78 mV, Jsc 37.03 mA/cm 2 , FF 78.35%, Eff 18.45%. The result shows improvement of Voc 8 mV, Jsc 0.57 A/cm 2 , Eff 0.5 % in comparison with the reference cell(homogeneous emitter structure) and improvement of Voc 3.7 mV, Eff 0.1 % as a function of heavy emitter size.