| 摘要 |
PURPOSE:To detect the leakage of a stored liquid having a higher density than water, by providing a water storage groove formed around a storage tank, a measuring chamber in the bottom part of this groove, and a light source and a sensor for quantity of light which are arranged in the measuring chamber and above the water surface respectively to face each other. CONSTITUTION:A water storage groove 13 is provided between a storage tank 11 and an oil retaining wall 12 to flow a leaked stored liquid into the groove 13, and a transparent plate 14 is provided in a part of the bottom face of the groove 13, and a sensor for quantity of light 15 is provided under this plate 14. A light source 16 is provided above the sensor 15; and when the leaked stored liquid is flowed into the groove 13 to intercept the light between the light source 16 and the sensor 15, the sensor 15 detects the change of the quantity of light to send a leakage signal to an alarm device and a recorder (which are not shown in Fig.) connected to Y and Y'. |
