Bechtel’s Nuclear, Security and Environmental global business operating unit contracted Greenberry to build a 16 foot diameter by 38 foot tall stainless steel, complex test vessel in the Vancouver fabrication shop. Fabrication consisted of three shell courses of 3/4” thick 316L stainless steel with a 10 foot skirt. Internals were comprised of (6) 36” diameter pulse jet mixers, spargers, bubblers, inspection ports, and internal supports. The elliptical head design included 53 nozzle penetrations.
The vessel was barged up the Columbia River to Richland, Washington, where it will be used to properly mix radioactive liquid wastes at the Hanford VIT Plant, formally known as the Waste Treatment and Immobilization Plant. In Richland, it is being installed in a facility specifically designed for full-scale testing of vessels at the Vit Plant. The non-radioactive testing is expected to be completed in 2017.
Greenberry served as the fabricator for this complex vessel. The fabrication work on this project was executed at two of our facilities: Corvallis, Oregon, and Vancouver, Washington.
This vessel was a complex design because of the number of nozzles and the number of internal jets. The top of the vessel had 53 nozzles. Greenberry used a rare and unique vertical milling machine to drill the nozzle holes. This machine was custom designed and built. By using this computer-controlled drill, we were able to maintain the tolerance levels.
Additionally, Greenberry used a 3-D laser scanner to map dimensional verification. Bechtel used the data from the mapping to overlay on the plans to verify the many dimensional attributes which were then confirmed by hand further. Bechtel is using this test vessel to gather data to verify the mixing design of nuclear waste. The results will assist Bechtel with method of waste storage.
The overall scope of fabrication services are highlighted below.