Tritium Tracing
Posted on July 28, 2022 Instrumentation & Equipment Design
Clients often come to Coanda when they have difficulty measuring some aspect of their process. A recent case involved tracking a particular process constituent at a field pilot as it travelled through their plant and comingled with other materials, including more of the same species. After considering several options and validation bench-tests (to ensure it would remain bound to the species of interest and not interfere with the process) Coanda recommended using a tritiated compound as a tracer.
Tritium, a radioactive isotope of hydrogen, has the advantage that it is relatively low risk due its extremely low penetrating power and the short biological half-life of the compound used. This is reflected by quite high allowable limits for handling without a specialized radiotracer licence from the Canadian Nuclear Safety Commission (CNSC). Coanda was able to procure the tracer, handle communications with the CNSC, and guide our client on a dosing strategy such they could perform the injection and sampling themselves – although Coanda routinely participates in field tests, this client preferred the cost savings of handling the injection with their own staff.
Process samples were shipped to Coanda where we developed a combustion sequence that converted all hydrocarbons (including the tracer) in the sample to water vapour and CO2, which were collected and analysed via liquid scintillation counting to determine the activity level. Incineration had the advantage that it would reliably and completely separate the tritium from all other compounds in the process without leaving any residuals that might interfere with further measurement.
The development and deployment of the technique occurred on a highly accelerated schedule – time from the initial client ask to “routine” sample analysis was half a year. This included a gated first phase for brainstorming and bench tests, procurement of materials, development of the injection plan and deployment at the field trials, as well as procuring and commissioning both the liquid scintillation counter and the incineration/collection system.