Tritium Measurement in soft waste

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Tritium laboratories accumulate large quantities of low level waste from items such as paper, Kimwipes®, plastics, cloths and gloves used in daily activities of operators and maintenance personnel.  Although this may not be the case, if personnel have worked in potentially active areas it is often assumed that their waste is contaminated with tritium.  During the course of a year, considerable waste in this category may have accumulated  some of which could be of a low enough level that it could be discharged into regular land fill.  However, because activity level is not positively established, the waste must be stored indefinitely in a low level waste facility, incurring additional costs.  Tyne Engineering's Model 7019-SWTM-001 is designed to measure the activity of each bag of potentially tritiated waste allowing for appropriate, efficient, cost effective discarding choices.

Model 7019-SWTM-001 measures tritium outgassing rate by capturing it in a bubbler subsequently monitored in a scintillation counter.  The equipment can also be used to characterize tritium contaminated waste such that personnel will become aware of which kind of waste is potentially more active and should be bagged together.  This will result in increased inactive waste accumulation and reduced amounts sent into long term storage.

• Cuts expenses by reducing long term waste
• Can monitor many bags of contaminated waste simultaneously
• Automatically timed operation with minimal operator involvement

The equipment records the cycle times of each drum operation, thereby determining the amount of air used to purge the bags.  Since air flow is according to a predetermined rate established by a mass flow controller, the total quantity of air transported through each bag is known.  A fifth bubbler is provided which takes ambient room air alone, monitors it for tritium without going through the bags and provides a background base line measurement.  This is a twice daily measurement, and does not need to be carried out more frequently than once every 12 hours.  It provides a number to which bag measurements are compared should tritium be present in the lab atmosphere.

Flow through the drums is provided by a wobble pump chosen for its quiet performance while delivering continuous reliable flow. The glass bubblers are easily removed from their sealed aluminum mounting brackets for conveyance to the scintillation counter.  The results of the scintillation counter can be printed on the waste bag for easy subsequent recognition.  When the monitoring is complete the drum will be put into purging mode to ensure no tritium from a previous bag remains. Lights on the control panel display the current phase of the system's operation.