| 摘要 |
PURPOSE:To detect exactly oil leakage extending over a long period of time, by detecting the oil leakage by a filter having oil permeability. CONSTITUTION:A detecting pipe is buried in the vicinity of an underground buried pipe 1. Oil leaking from the underground buried pipe 1 is diffused or is floated by underground water, and is collected under an oil receiving sheet 2. Leaked oil passes through a hole provided on a filter protecting pipe 5, and reaches a ceramic filter 4. The ceramic filter 4 transmits water and oil, but does not make earth and sand pass through, therefore, only water and oil invade into the filter 4. This invaded oil is detected from the ground by a detecting pipe 6 leading to the ground. As for the detecting method, a method for inspecting the mixtue of oil by pumping up underground water in the detecting pipe 6, a method for deciding the mixture of oil by a variation of electric resistance between electrodes by inserting two electrodes into the pipe 6 from the ground, or the like are available. |
