14 Oct Another reactor lift completed

The nearly three-meter-wide metal ring, which was located around the top of the DR3 reactor tank, has been successfully lifted out. Similar to the lift performed earlier this year, today's operation was executed with high professional expertise from the Dutch company Mammoet and custom-fabricated equipment from the Aalborg-based company Bladt Industries.

EOnce again, the red and yellow cranes have demonstrated their power at Denmark's largest research reactor, DR3. Earlier today, the Dutch heavy transport and lifting company Mammoet hoisted the 17-ton shielding ring that was positioned around the top of the reactor tank. Danish Decommissioning has thereby taken a significant step forward in the decommissioning of Denmark's largest research reactor.

The shielding ring is technically referred to as the Top Shield Ring or TSR. The ring weighs 17 tons, and years of reactor operation have exposed it to neutron bombardment, rendering its inner surface highly radioactive. The lifting operation was therefore conducted behind a protective concrete wall using remote-controlled equipment. The heavy shielding ring was lowered into a shielding container, which had been lifted down from the 10.5-meter-high reactor block. Here, it was placed in another shielding container and transported to Danish Decommissioning's interim storage facility. With shielding, the Top Shield Ring weighs nearly 60 tons.

In May 2014, the reactor plug itself, which had been situated inside the ring, was extracted, and since then, the reactor tank has been sealed with a movable lid that can be slid aside on rails. First, the ring was lifted, and then it was moved aside while the movable lid was rolled back over the tank. Mammoet's massive cranes were remotely operated by a small team, who were well-shielded at the bottom of the reactor hall.

The operation was largely planned similarly to the lifting of the reactor plug. As the now-lifted Top Shield Ring has the shape of a vanilla wreath, additional shielding was required inside the ring. This special shielding container was also custom-fabricated by Bladt Industries in Aalborg.