| 摘要 |
PURPOSE:To enable measurement of turbidity at a high accuracy continuously and by direct reading, by a method wherein the passage of signals which are passing at different distances with a transmitter and a receiver immersed into a sewage and both passages are compared to measure the degree of the turbidity of the sewage from the resulting attenuation rate determined. CONSTITUTION:Two sets of light emitting devices A1 and A2 and light receiving devices B1 and B2 are set in a sewage W apart at a distances d1 and d2 and lights of the same intensity E are radiated to light receiving devices B1 and B2 from the light emitting devices A1 and A2. The lights of the intensity E in the sewage is weakened by turbid substances and the light receiving device B1 detects a signal attenuated to the intensity P1 while the light receiving device B2 does that attenuated to the intensity P2. When the ratio between intensities of both the lights received is determined, the attenuation rate alone in the sewage W can be obtained regardless of attenuation of light due to pollution of light emitting and receiving surfaces. The density of the sludge corresponding to the attenuation rate can be calculated immediately by previously determining the sludge density vs attenuation rate relationship. |
