| 摘要 |
<p>PURPOSE: To measure the three-dimensional temperature distribution in a digester without blocking the flow of chips, by providing winding an optical fiber between plural steps of strainers and a digester main body, and measuring the temperature of a solution for digesting from a Raman scattered light from the inside of the optical fiber. CONSTITUTION: After an optical fiber 21 is wound in a space between a continuous digester main body 1 and a net form upper stage side strainer 4, for example, the optical fiber is picked up out of the main body 1, and set by surrounding a lower stage side strainer 4. Since a solution for digesting (an alkaline solution) with a specific temperature extracted from the trainers 4 separating from chips is contacted with the optical fiber 21, the temperature of the optical fiber 21 at the contact part is changed. Therefore, laser beams of a light generating source are injected to the optical fiber 21 through a directional connector 22, and by detecting the reaching time difference of the Raman scattered light in the optical fiber extending direction returned to the injecting end side, that is, the distance in the extending direction, and the strength of the Raman scattered light, the temperature distribution of the alkaline solution in the inner peripheral direction of the main body 1 can be measured.</p> |
