| 초록 |
Thermococcus onnurineus, which had been isolated from a deep-sea hydrothermal vent area in 2002, has been recently found to be able to grow on carbon monoxide (CO) evolving hydrogen (H2) via water-gas shift (WGS) reaction. In this study, using Linz-Donawitz gas (LDG), one of the steel mill by-product gases, as a CO source, the mass production of bio-H2 was demonstrated by the continuous culture of T. onnurineus in a 1,000L gas-lift bio-reactor. The continuous cultivation was conducted for 40 days varying the gas supply rate of LDG or the gauge pressure in a reactor at fixed dilution rate of 0.042 h-1. As a result, it was observed that both the cell growth and the volumetric H2 production rate (HPR) were increased depending on the LDG supply rate mainly due to the increase of gas-liquid mass transfer rate. The gauge pressure in a reactor was also found to be a key variable in WGS activity of T. onnurineus. At LDG supply rate of 0.2 vvm and gauge pressure of 1.5 bar, the cell concentration (OD600) and HPR reached to the maximum values of 5.4 and 247 mmol/L/h, respectively, with a daily production of H2 of 50 Nm3. |
