Analysis of operational records in the bituminization demonstration facility; Investigation of the cause of fire

Shibata, Atsuhiro  ; not registered; not registered   ; Koyama, Tomozo

Operational records in the bituminization demonstration facility in 97-M46-1 campaign were analyzed in order to investigate the cause of fire. Operational records which are different from ordinary level in this campaign are drum weight, temperature at 7th zone and extruder torque. So we investigated past campaign data about these records. The results are as follows. (1)In some campaigns, drum weight was lighter, temperature at 7th zone higher, and torque higher. (2)When drum weight is lighter, temperature at 7th zone becomes relatively higher. (3)In the case that higher temperature was measured at 7th zone, drum weight was sometimes less than the past average. (4)When the extruder's torque increases, it sometimes influences drum weight and temperature at 7th zone. The mixture of salt and bitumen became hotter from 28 B. As the heat source, both frictional resistance and exothermic chemical reaction can be considered. Frictional resistance came out with increase of the torque. So we checked some operational parameters to investigate what increases the torque. Feed rate of waste solution is related with the torque increase. The other parameters are not related with it. Now we can not specify any causes of the torque increase from 27B, the feed rate of waste solution is however possible to be one of the causes.