| 摘要 |
<p>PURPOSE:To improve a measurement precision by using gas, which is dehumidified by one dehumidifier, as dried gas for purge of the other dehumidifier, in the gas analyzing unit provided with a set of semipermeable membranes. CONSTITUTION:Switching valves 14 and 18 which operate synchronously and air opening tube 17 are provided in the flow path of semipermeable membranes 12 and 12a and infrared-ray gas analyzer 15. In this unit, gas to be inspected is sent to analyzer 15 through dehumidifier 12, pump 13 and valve 14; and after a value obtained by measuring this gas is stored, this gas is supplied through air opening tube 17 and switching valve 18 as gas for purge of the other dehumidifier 12a, and meanwhile, reference gas caused to pass through dehumidifier 12a is supplied through pump 13a and valves 14 and 18 as gas for purge of dehumidifier 12. Next, valves 14 and 18 are switched to exchange flow paths of inspected gas and reference gas, and a value obtained by measuring reference gas passing through analyzer 15 is subtracted from the measured value above of inspected gas, thus obtaining the concentration of inspected gas components.</p> |
