| 摘要 |
<p>PURPOSE:To always feed a reducing gas by an exact amount by calculating the amount of gaseous SO2 from a function of the flow rate of a drawn gaseous mixture and the concn. of gaseous SO2 in accordance with the measured value of the flow rate and mixing the reducing gas corresponding to the gaseous SO2. CONSTITUTION:Chambers 1, 1', 1'' packed with an SO2 adsorbent are placed at an adsorbing zone 2, a desorbing zone 3 and a cooling zone 4, respectively. Part of a gaseous mixture of a desorbing gas with gaseous SO2 fed with a blower 13 is fed to a reducing tower 15, and the remainder is circulated to the chamber 1'. At this time, the flow rate of the gaseous mixture flowing through a duct 14 is measured with a flowmeter 17, the measured value is inputted in a function generator 24 to calculate the concn. of gaseous SO2, and from the calculated value and the measured value of the flow rate the amount of gaseous SO2 is calculated with an operator 21. The amount of gaseous H2 corresponding to the amount of gaseous SO2 is then calculated with a controller 22, and a control signal is given from the controller 22 to a controller 23, where it is compared to the actual flow rate measured with a flowmeter 20. The controller 23 gives a signal for controlling a control valve 19 so that the difference is made zero, and gaseous H2 is fed by a prescribed amount.</p> |
