Use of carbon steel containers for storing spent nuclear fuel - - under conditions preventing corrosion

摘要

Containers for storing spent nuclear fuel until its radiation drops to the safe level, made from ordinary carbon steel instead of expensive stainless steel, are prepared for use and protected against corrosion by the following measures : mechanical cleaning; degreasing; pickling in 10% HCl soln. contg. 5% of a corrosion inhibitor; rinsing with water; pickling in 3% oxalic acid; polishing with a soln. contg. 1-8 wt.% oxalic acid and 0.7-5.5 wt. % H2O2; rinsing again; rinsing periodically with a corrosion-inhibiting soln. contg. 12.6 g/l. H3BO3 and at least the same amt. of NH3 (pH7); and eventually using the same soln. as a shielding medium dispersing the heat generated during the radioactive decomposition. Pref. the storage container wall is coated from the water level upwards with an epoxy resin or stainless steel plating as corrosion prevention.