| 摘要 |
PURPOSE:To eliminate measuring errors regardless of quick changes in the concentration of oxygen in a measuring gas by providing the gas accumulation chamber having a tiny hole for inflow of the measuring gas and the solid electrolytic element equipped with a measuring electrode and a comparison electrode on both surfaces thereof. CONSTITUTION:The measuring gas 1 containing oxygen and steam exists at a void in a furnace wall 2. A gas accumulation chamber 8 is arranged in the measuring gas by mounting a body mounting base 4 on the furnace wall 2 and a porous filter 9 is provided at the tip thereof. A solid electrolytic element 10 is equipped with a measuring electrode 11 and a comparison electrode 12 to form a solid electrolyte type oxygen concentration detector 13. A comparison gas supply mechanism 34 removes steam in the measuring gas with a dehumidifier and feeds the measuring gas to the comparison electrode section 12 of the detector 13 as comparison gas. The dehumidifier comprises a first semi-permeable membrane gaseous phase dehumidifier 17 adapted to dehumidify the measuring gas running therethrough and a second semi-permeable membrane gaseous phase dehumidifier 23 adapted to humidify original gas fed and supply it to the said dehumidifier 17 as purge gas. |
