OBSERVATION OF BRICKWORK OF PHOSPHORUS OVENS USING RADIOACTIVE PREPARATIONS

The supervision of furnace-wall thicknesses during operation by means of radioactive isotopes has definite advantages. A close examination of furnace walls and floor is ordinarily possible only when the furnace is completely empty. But since this requires several weeks, during which the furnace cannot be used, it is practicable only when extensive repairs are necessary. However, this is usually not the best time to replace wornout sections. On the other hand, radioactive substances can be installed to indicate when the furnace lining must be replaced (either completely or partially) without having to put the furnace out of operation. After a radioactive substance is applied to the wall, it is necessary to decide where the substance shall remain. Co/sup 60/ was found both in ferrophosphorus (3.4 nC/kg) and in phosphorus slag (0.75 nC/kg). The specific activities which were found preclude any danger from radiation. A slight amount of activity was left in the furnace. Whenever the furnace is emptied, this activity can be measured to obtain information on currents. (auth)