A special technologies of dilution and immobilisation of irradiated very enriched uranium (HEU) fuel has been created by specialists at the National Nuclear Centre (NNC) in Kazakhstan. In 2010, NNC, with each other with the US Battelle Power Alliance undertook a substantial-scale project to convert investigation reactors IVG.1M and IGR to use low enriched uranium (LEU) fuel. The function was element of a international initiative to consolidate and get rid of stockpiles of HEU and transfer investigation reactors to low enriched nuclear fuel.
This also necessary solving the situation of disposing of irradiated graphite from the initial core of the IGR reactor, which had been stored for a lot more than 60 years. NNC specialists created their personal conceptual technologies for dilution and immobilisation. Subsequently, the technologies was authorized by specialists from the US Idaho National Laboratory, Sellafield in the UK and International Atomic Power Agency (IAEA) specialists.
“To address the situation of disposal of irradiated graphite fuel from the initial core of the IGR reactor, NNC specialists proposed their personal conceptual dilution and immobilisation technologies,” mentioned NNC Director Basic Erlan Batyrbekov. “The essence of the technologies lies in the dilution of very enriched uranium fuel by grinding and mixing it with depleted uranium dioxide and its subsequent encapsulation in a cement matrix.”
In assistance of this technologies, investigation was carried out, which confirmed the compliance of the created matrix with the criteria defined by the guidelines and requirements of Kazakhstan, as effectively as with the needs of the IAEA. Primarily based on the outcomes of investigation and experimental testing, a technologies was created for the dilution and immobilisation of irradiated graphite HEU, which was sent to the IAEA for specialist assessment.
Immediately after reviewing the optimistic conclusion was sent to the NNC. The Specialist Opinion emphasises the uniqueness of the technologies and its basic reliability. In addition, IAEA representatives noted that thanks to a effectively-planned and implemented investigation programme in assistance of the project framework for immobilising diluted HEU-IGR fuel, all the ambitions have been accomplished. Currently, we can say that this technologies can be employed for related fuels in other nations participating in the programme to minimise HEU.
Image: New technologies for treating HEU fuel has been created by the NNC in Kazakhstan (courtesy of Rosatom)
