Shepley Engineers were contacted by the National Nuclear Laboratory based on the Sellafield site to determine the viability of decontaminating a transport bowser which had been historically used for transporting radioactive liquors.
The Bowser had a remnant heel of liquor which contained radioactive solid residues. As part of the scope of work, SDS were also asked to provide a methodology of filtering the solids prior to any liquor being disposed of to the building effluent liquor treatment tank.
SDS provided a concept which used high pressure water jetting to refluidise the remnant solids in the heel liquor and also decontaminate the internal walls of the tanker. A bespoke filter system was designed, which allowed the effluent to be pumped out to a mobile dual filter assembly unit, that used removable filter bags (100μm, 50μm and 25μm) to extract the radiactive solids.
Results:
The initial readings on the bowser were 26,500 cps, this was reduced to 167cps after decontamination, with radiation dose readings being reduced from 800μSv/hr down to 2μSv/hr.
