| 摘要 |
PURPOSE:To measure methane concentration quickly by contacting the microbiological electrode, in which methane utilizing bacteria are sealed, with gas to be measured, and sensing the reduction in dissolved oxygen in a solidified microbiological layer as an amount of reduction or reducing speed of the output current of the electrode. CONSTITUTION:In an outer tube 9, are contained platinum cathode 5, an alminum anode 6, and KCl elctrolyte 7. The microbiological electrode 10 is provided between a separating film 4 of an oxygen electrode and a dialysis film or gas transmitting film 3, and attached to a measuring cell 12. The methane utilizing bacteria 1 which oxidize methane and consume oxygen are sealed in the microbiological electrode 10. Air is sent into the cell 12. The gas to be measured is injected from an injecting port 16 for 1-5min at every 4--20min interval, dilluted by air, and contacted with the electrode 10. Methane is diffused in the bacteria 1, and oxidized by the bacteria 1. Oxygen is consumed and the concentration of the dissolved oxygen in the vicinity of the separating film 4 is reduced. Therefore the output current of the oxygen electrode is decreased and recorded in a recorder 13. The relationship between the methane concentration of the gas to be measured and the reduced value of the current has been obtained for standard methane gas, and the methane concentration is obtained from the height of the peak. |
