| 摘要 |
PURPOSE:To safely and economically culture hydrogen-oxidizing bacterium with making possible to keep mixed gas as raw material within explosion range and completely utilizing the raw material gas by supplying mixed gas of H2 and CO2 and oxygen gas to culturing solution of hydrogen-oxidizing bacterium in a specific method. CONSTITUTION:In a cultivation of hydrogen-oxidizing bacterium, e.g. Alcaligenes.eutrophus ATCC 17697, hydrogen to be substrate and carbon dioxide gas in a gas state previously mixed in a gas chamber 2 are supplied into a culturing tank 1 containing culturing solution with remaining space in upper part. On the other hand, 100% oxygen is solely and directly supplied into the culturing solution. Whole gas not utilized by the substrate accumulated in the space in the culturing tank 1 not dissolved in the culturing solution is circulated through a closed circulating system 41 and returned into the culturing solution. Furthermore, the amount of dissolved oxygen in the culturing solution is monitored by a dissolved oxygen sensor 5 and supplying of oxygen is controlled so that the amount of dissolved oxygen not to be <=1.8ppm in logarithmic propagating period and supplying of ammonia is controlled by a pH sensor 6 so as to keep the culturing solution at pH7. |
