METHOD AND DEVICE FOR MONITORING OPERATION OF CENTRIFUGAL THIN FILM DRYER

摘要

PURPOSE:To detect the sticking of scale by changing the supply rate of liquid while detecting the temp. of the transfer surface near the position where liquid films annihilate in a centrifugal thin film dryer and detecting the correlations between the rate of the change thereof and the change in the temp. of the heat transfer surface. CONSTITUTION:In the stage of supplying supply liquid 4 such as waste radioactive liquid or the like to a centrifugal thin film dryer 1, and drying and pulverizing the same, its flow rate is converted to an electric signal with a flow rate detector 3 provided to the liquid supply pipe and the electric signal is fed to a setter 7 for the supply rate of liquid. Here, the detected value and the set value are compared and a control valve 2 for supply rate is operated with a signal selecting circuit 6 so that the flow rate is made equal to the set value. On the other hand, temp. detectors 9-12 are installed on the heat transfer surface of the dryer 1, and the temps. measured therewith are converted to electric signals. The electric signals are transmitted to a detecting circuit 13 for the shape of temp. distributions, which estimates the temps. at the various points on the heat transfer surface in accordance with the input signals and makes the shape of temp. distributions. The shape is compared with the shape of temp. distributions in the normal time with a decision circuit 14 for generation of abnormality, whereby the condition of scale sticking on the heat transfer surface is estimated.