Costain has been granted its first nuclear-related patent.

The patent, which involves a more efficient method of immobilising radioactive sludge in a cement matrix, has been granted after an extensive four-year examination process from the Patent Office.

Nuclear power plants store used fuel canisters in cooling water ponds to enable radiation levels to decrease before the fuel is reprocessed. The storage process leaves a radioactive sludge in the pond which can be immobilised by mixing it with cement for safe, long-term storage. The immobilisation process operates on a batch-wise basis.


Costain developed an improved process to enable the cementation of larger quantities of radioactive sludge more quickly and reliably than at present. The proposed process could deliver a six-fold increase in the number of drums filled per week from two to twelve.

The innovative approach was developed by process engineers Jaswinder Singh and Lee Scott, who were jointly awarded the Innovation Award at the Costain Celebrating Success event in December 2006.

Costain decided the technique was sufficiently innovative to apply for a patent. The application was granted after a comprehensive examination process by a Patent Office examiner.

"We are extremely pleased to have been granted our first nuclear patent," said Paul Campbell, Nuclear Process Sector Director. "This is one of a number of our novel approaches to the problems encountered when decommissioning nuclear plant."

(CD/GK)