Four large corrosion-resistant process vessels recently arrived at Hanford’s Waste Treatment and Immobilization Plant (WTP), or Vit Plant, completing a significant step for construction of an effluent management facility and bringing the project one step closer to vitrification by 2022.
The vessels are internal components of the effluent management facility, which serves as part of the Vit Plant Balance of Facilities support infrastructure. The vessels will aid the process to receive, hold, and transfer liquids throughout the effluent management facility. During low-activity waste (LAW) vitrification, secondary liquid waste is generated from the melter off-gas system and during waste transfer pipe flushing. These liquids go to the effluent management facility where excess water is evaporated, and the remaining concentrate is sent back into the vitrification process.
“We now have 12 of 14 Balance of Facilities buildings in either the startup-and-testing phase, or fully operational to support the commissioning phase,” said Tom Fletcher, WTP project director for the U.S. Department of Energy’s Office of River Protection. “The effluent management facility represents the final major WTP construction effort to support the direct feed low-activity waste (DFLAW) treatment approach.”
The vessels range in size and have a combined weight of more than 56 tons with a total capacity of more than 73,400 gallons. The largest of the vessels stands 45 feet tall with a 14-foot diameter and weighs 24.5 tons with a 38,000-gallon capacity.
Washington state-based manufacturer Greenberry Industrial fabricated the vessels for Vit Plant prime contractor Bechtel National Inc. (BNI). The vessels were fabricated, welded and tested at the company’s Vancouver, Washington, and Corvallis, Oregon, facilities, then transported to the Vit Plant via a heavy-haul trailer. The largest vessel was shipped at nighttime to minimize traffic impacts and improve transportation safety.
“Receiving these large vessels is an important step in moving the effluent management facility from a civil construction phase to a mechanical and piping installation phase,” said Valerie McCain, BNI principal vice president and WTP project director. “With a majority of the concrete and structural steel work complete, we can now move forward with installing piping, equipment, and vessels.”
Work crews have already installed two vessels from Greenberry Industrial and expect to install the four new arrivals in spring 2019. Crews have also begun piping installation along with heating, ventilation and air conditioning ducting and electrical work.
The DFLAW approach initiates the treatment of low-activity Hanford tank waste, increases available double-shell tank space, and provides valuable lessons learned to aid startup and commissioning of other portions of the WTP.