| 摘要 |
PURPOSE:In the aerobic liquid cultivation of a microorganism, the volume of the gas passed is fixed and the oxygen concentration of the gas composition is changed to keep the concentration of the dissolved oxygen to the predetermined level with high accuracy. CONSTITUTION:The oxygen dissolved in the culture mixture is detected with the terminal 2 in the cultivation tank 1 and the value is sent to the dissolved oxygen meter 3, then the signal is input to the computer 4. The computer memorizes the relationship between the amount of dissolved oxygen and changes in factors effecting on the concentration of oxygen dissolved in the culture mixture previously to calculate the difference from the set value or control value of the oxygen concentration on the basis of the data input. Meanwhile, the flow rates of air and oxygen that are detected by flow detector 5 also are converted to electrical signals and input to the computer 4. On the basis of the dissolved oxygen detected, the computer 4 sends signals to the valves for controlling the flow rate of air and oxygen 6, 7 respectively. |
