| 摘要 |
<p>PURPOSE:To stir surely sample water for a long time by providing a dissolved oxygen electrode in the position where its measuring end is located in a measuring vessel and providing a pump which collects the sample water through a sampling port opened in the measuring vessel and releases said water. CONSTITUTION:The sample water in a measuring vessel 21 is sucked through a sampling port 31 by a pump 33 and after the water is pressurized, the water is returned through an outflow port 32 into the vessel 21. The sample water flows vigorously on the surface of a dissolved oxygen electrode 3, and flows to the outside of the vessel 21 by passing the strainer 7. A stop valve 6a provided in a lower opening 6 is closed and a stop valve 12 is opened by a process control unit 19 to supply air through an air supply port 11 for aeration, thereby aerating the sample water. The concn. of the dissolved oxygen in the sample water in the vessel 21 is measured with the electrode 3 and a measuring device 4 for dissolved oxygen and the aeration is stopped at the point of the time when the concn. of the dissolved oxygen attains a prescribed value.</p> |
