| 摘要 |
PURPOSE:To control the amount of additive to not wastefull usage by a method wherein a final value of variations is calculated from the intial value appearing in response to the variations of concentration of a certain material, and the resulting final value and a pre-measured time delay element are used to control the amount of adding of another reactive material so that the delayed time can be neglected. CONSTITUTION:As an illustration, a purification process of crude argon is described. Oxygen in crude argon obtained from the air separator 1 is reacted with hydrogen, and formed water is removed to produce a high purity argon. In this process, argon is sampled at the measuring location 10, oxygen concentration is measured by the oxygen analyzer 9, the measured result is input to the calculator 18, and the intial variable value of oxygen concentration is used to calculate the final variable value. Also, the flow rate of crude argon at the measuring location 12 is measured, and the result is used with the result from the calculator 18 to permit the calculator 13 to provide the value of the amount of hydrogen which should be supplied to the first purifier 4 and the second purifier 6 through conduits 5 snd 7. |
