The leakage of unit or pipeline in the cold box needs removal of perlite treatment. Since it is uncertain whether there is a leakage point in the cold box, it will have a certain impact on removal of perlite. No matter whether the leakage is liquid or air, the sand filling holes at the top should be opened first, so that the residual gas in the cold box can be slowly discharged into the atmosphere. The oxygen content of the gas in the cold box and the pressure indication in the cold box should be strictly monitored in removal of perlite process. In the process of sand stripping, it is particularly important to avoid the formation of sand free area in the middle of the cold box, so as to avoid sand storm caused by the sudden drop of pearlite sand.
