According to DOE-EM, the team recently launched a new technology and equipment test at the site to prove the capability of remote-handled robotics to properly weld access points in the site’s Calcined Solids Storage Facilities, where 4,400 cubic meters of calcine waste is stored.
Background: Under an agreement with the state of Idaho, all of INL’s calcine waste must be removed from the state for permanent disposal. The DOE had converted liquid high-level radioactive waste into calcine, which is similar in consistency to sand, until those operations ended in 2000. The waste was created during historic spent nuclear fuel reprocessing runs at the Idaho Nuclear Technology and Engineering Center.
The calcine was transferred to large stainless-steel bins encased in six concrete vaults called bin sets. Due to the design of one of the six bin sets, called bin set 1, a nearly 20-foot long, 8-inch diameter pipe, or access riser, must be installed on the bin to retrieve the granular waste.
The test: During the test, conducted at a full-scale replica of bin set 1, engineers and operators used the robot, operated remotely from a centralized control, to connect an access riser pipe segment to a steel plate and then cut the steel plate.
In practice, the robot is designed to travel down the 20-foot pipe and weld it to the bins. Once the weld is complete, the same robot is fitted with equipment to cut a hole into the bins at the welded point of the pipe.
According to DOE-EM, the project team will next perform more extensive integrated tests to closely imitate the process to be performed at the bin sets.
He said it: Mechanical engineer Jeremiah Voss said that the testing, which included several successful welds and cuts by the robot, demonstrates that DOE-EM can successfully retrieve the calcine waste for disposal.
“We gained a lot of valuable information from the test and saw that the technology functioned the way we had hoped it would,” he said. “Going forward, we know what steps we need to take to improve the robot design and to better prepare for actual retrieval of calcine at the bin sets.”
Voss added that the robotics equipment is important to the overarching mission of Idaho’s Calcine Disposition Project and DOE-EM and its contractor Idaho Environmental Coalition.
