Offshore system cuts radioactive waste costs

• Offshore Radioactive Waste Treatment [222,469 bytes]

AEA Technology plc, Didcot, U.K., has developed an offshore descaling system it claims can cut the costs of treating radioactive waste from production platforms.

Naturally occurring uranium and thorium from producing wells is typically transported to shore for treatment.

AEA has devised a way of treating radioactive waste offshore for reinjection at the source.

Approach

Instead of the conventional descaling process, which requires production tubulars to be transported to shore for descaling in a long horizontal chamber, AEA has devised a closed-loop system with a vertical chamber.

The vertical chamber can be shorter than the equivalent horizontal unit because gravity aids the descaling process and can therefore be fitted offshore.

The AEA system (see illustration, this page) is said to reduce waste treatment costs by removing the cost of transporting contaminated production tubulars to shore for treatment.

Jack Stewart, technical sales engineer at AEA, said: "The only reason descaling has not been carried out offshore before is lack of space in laydown areas.

Cost savings

"Our system uses the same process as onshore treatment, but relies on the fact that it is easier to clean tubes vertically.

"This brings a cost saving of about 30% compared with conventional waste treatment."

Stewart said the system can typically handle 40 production string joints/day.

Contaminated waste is collected in sealed hoppers that can be removed and maneuvered by crane for later reinjection.

Copyright 1997 Oil & Gas Journal. All Rights Reserved.