| abstract |
Appts. for determining continuously by accurate measuring techniques, the degree of pollution esp. of the surface, of a flowing watery fluid by oil, has a light source (I) and a light detector (II). (I), by which a beam of UV light capable of exciting the oil to fluorescence,is directed towards the surface of the flow, is mounted on a float together with (II). (II) has selective sensitivity for light outside the UV range. The float consists of >=2 pontoons arranged alongside each other and joined by >=1 bridge. (I) and (II) are aligned towards the fluid flowing between the pontoons. (I) are pref. formed by Hg vapour lamps with a filter allowing the passage of UV light. (II) pref. consists of a semiconducting photo-element, esp. a phototransistor. The windows of the detectors canot become soiled by contact with il, and the presence of oil on the surface of the flow is detected with certainty. |