Foam application of oxalic acid as a decontamination waste minimization tool

The use of foam in applying decontamination solutions has proven to bc an effective waste minimization strategy. Initial trials in 299-H indicated a 70% reduction in waste volume. An overpressurization of the equipment during a decon operation. however, indicated the need to better define chemical compatibility and to develop inherently safer equipment. A foamer system with an open solution vessel and 1:1 ratio pneumatically actuated pump was modified, tested and found to operate satisfactorily. Laboratory tests indicate no significant incompatibilities between the foam agent and oxalic or dilute nitric acid solutions. Oxalic acid/foam agent compatibility was verified in the foamer vessel for concentrations up to 4 weight percent. It is recommended, however, that 1 weight percent oxalic acid be used in plant decon operations. The defoamer used previously is no longer in production. A new defoamer remains to be tested. Limited use of the foamer in 299-H can now be initiated. Long term use of foam and its impact on waste tank processes is being reviewed