| 摘要 |
PURPOSE:To discharge sample water after measurement without fail and to clean a required part by providing ports for supplying air for exposure and air for cleaning in the lower part of a measuring vessel, and by supplying air with the upper switching valve of the measuring vessel and with the lower open valve opened. CONSTITUTION:A port 8 for supplying air for exposure and a port 21 for supplying air for cleaning are provided in the lower part of a measuring vessel 2a. After the completion of measurement, the upper and lower valves 4 and 5 of the vessel 2a are closed and opened respectively, and a larger quantity of the air for cleaning than that of the air for exposure from the supply port 8 is supplied from the port 21 into sample water. Then, the sample water is discharged rapidly and surely by the air for cleaning, while the valve 5, the inner wall of the vessel 2a, a dissolved oxygen electrode 3, etc. are cleaned excellently by the ripples on the boundary surface of the sample water with the air, the air-bubbles in the sample water, etc. As for the valve 4, it is cleaned by cleaning air supplied under the condition that the sample water is injected into the vessel 2a with the valves 4 and 5 opened and closed respectively. By the sure discharge of the sample water and the excellent cleaning, the oxygen utilization velocity of a mixture solution in an exposure tank can be measured with high accuracy. |
